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Development and distribution of Castanea and Aesculus culture during the Jomon Period in Japan
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Development and distribution of Castanea and Aesculus culture during the Jomon Period in Japan Junko Kitagawa, Yoshinori Yasuda International Research Center for Japanese Studies, 3-2 Oeyama-cho, Goryo, Nishikyo-ku, Kyoto 610-1192, Japan Available online 11 September 2007
Abstract Castanea and Aesculus trees were protected for consumption of nuts as food during the Jomon Period. Climatic factors affected the selection of kinds of consumed nuts. Castanea was mainly consumed during warm periods and Aesculus was consumed during cold periods. However, this could have been a regional phenomenon in northern Japan. It is possible that in southern warmer areas Castanea either might be protected constantly, or the protection of these plants was not necessary because forest productivity in the southern area is greater than that of the northern area. To understand the influence of temperature on Castanea hansaibai, pollen analysis was conducted at the Satohama site. In addition, the distribution of the intermediate stage between wild and domestication (hansaibai) during the Jomon Period was studied based on pollen analyses. At the Satohama site, protection of Castanea started during the warm period in the Early Jomon Period (7000–4500 years BP) and continued to be observed during the next cold period. The Tohoku region (the northern part of Honshu Island) and the Hokuriku region (Japan Sea Coast area in Central Japan) was the main distribution area. In this study, no evidence of the protection of either species in Western Japan was detected. Climate and the necessity for large amounts of food preservation for winter might influence this activity. r 2007 Elsevier Ltd and INQUA. All rights reserved.
1. Introduction The Jomon Period started during the final part of the Pleistocene, about 16,000 BP when the first pottery in Japan appeared (Tsutsumi, 2002). It was the end of the Ice Age and climate warming had started. Deciduous broadleaved forest was expanding to the north. The Jomon Culture developed using abundant resources in the deciduous forest and gathering was an important activity to gain food. Human interaction with forests resulted in the creation of secondary forests in which Quercus subgen. Lepidobalanopsis is dominant in Honshu Island. Among species in secondary forests, the Jomon people selected and preserved plants which were useful for them. By keeping the forest in a constant condition, a stable food supply could be gained. Primitive woodland management started. A plant utilisation procedure, the intermediate stage between wild and domesticated, was developed. At this stage, human beings are not involved in planting seeds Corresponding author.
E-mail address: [email protected] (J. Kitagawa).
intentionally, but extensive stands develop by protecting trees from cutting. Nakao (1976) coined a word, hansaibai (han and saibai, i.e. half and cultivation, respectively), taking examples; e.g., wild rice in North America, Pyrus ussuriensis in North Korea and para gum in Amazonia. Harlan (1992) also described the intermediate stage. The main techniques are bringing seeds to the villages, protecting them from cutting, and owning trees. In the hansaibai phase, human beings are involved neither in planting seeds intentionally nor in reproduction. Protection and preservation are the techniques. It is easy to imagine that people selectively preserved or grew Castanea and Aesculus near the settlement areas to get enough food, since growing chestnuts and horse chestnuts is not difficult (Nishida, 1981; Yokoi, 1989). Castanea crenata and Aesculus turbinata are woody plants. Both have been possibly cultivated and utilised since the Jomon Period (Nakao, 1976; Minaki, 1994; Yasuda, 1995; Sato, 2003). However, the methods might be very primitive. Until recently, the selective protection of these trees, especially Aesculus trees was observed (Matsuyama, 1982; Kitagawa et al., 2004).
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At Sannai-Maruyama site and Kamegaoka site, hansaibai of Castanea and Aesculus is suggested by pollen analysis (Hori, 1959; Nitobe, 1973; Yasuda, 1995; Kitagawa and Yasuda, 2004) and the relationship between climate and hansaibai of Castanea trees and Aesculus trees in Japan was revealed (Kitagawa and Yasuda, 2004). However, this could have been a regional phenomenon because both the Sannai-Maruyama site and the Kamegaoka site are located in Aomori Prefecture, near the northern limit of Castanea distribution. Even though large amounts of chestnuts and horse chestnuts were yielded in other areas, it is possible that those nuts were gathered from far places. The Kitaboriike site in Mie Prefecture from the Yayoi Period may be a good example (Yasuda, 1989) where pollen analysis did not indicate the possibility of hansaibai of Aesculus at the site. However, the Satohama site is an example of the opposite situation. Although few chestnut remains were detected, high percentages of Castanea pollen, which might indicate hansaibai activity, were observed (Education Board of Naruse Town, 1999; Yoshikawa and Yoshikawa, 2003). It is important to reveal what conditions made the difference for hansaibai activity. A possible cause is temperature since Castanea trees are susceptible to disease during cold periods (Shiosawa, 1988). Branches are also harmed by low temperatures, and tolerate 510 1C in the early winter, 1522 1C during the coldest period and 36 1C in the early spring (Yamamoto and Sakai, 1977). The coldest temperature recorded in Aomori is 18.7 1C (on February 20, 1945: Japan Meteorological Agency). This indicates that Aomori might be beyond the northern limit of Castanea growing during the cold period. Although alternation of Castanea and Aesculus hansaibai was observed in Aomori prefecture, different phenomena may be seen in warmer places. To understand the influence of temperature on Castanea hansaibai, pollen analysis was conducted at the Satohama site where the lowest recorded temperature is 9.3 1C (February 7, 1984; Japan Meteorological Agency), as well as five other sites (Futatsumori site in Aomori Prefecture; Moniwa site in Miyagi Prefecture; Ondashi site in Yamagata Prefecture; Juno site in Saitama Prefecture; and Sakuramachi site in Toyama Prefecture) (Fig. 1). In addition to it, the sites where hansaibai activity is detected, including previous studies, are plotted on a map to show the distribution of hansaibai of both trees. In this paper, calendar years for each period of the Jomon culture are provided based on Dictionary of Japanese Archaeology (Yamamoto and Matsui, 1988), although slight differences exist among sites due to difference of the timing of cultural development. 2. Research site descriptions 2.1. Satohama Over 120 shell mounds have been identified around Higashimatsushima Bay. The Satohama site (Figs. 1 and 2)
Fig. 1. Analysed Jomon archaeological sites. Dots indicate the analysed sites.
is located at 381200 N, 1411080 E on Miyakojima Island. The circumference of the island is about 15 km and the site has been measured about 640 m from east to west and about 200 m from north to south. The annual average temperature in Shiogama close to the Satohama site was 11.3 1C in 2002 which was 1.2 1C higher than that of Aomori City (Japan Meteorological Agency). Miyakojima Island used to be connected to Honshu Island in the early Holocene, but was separated around 7500 BP due to the marine transgression, and the sea level reached its present position around 6800 BP (Matsumoto, 1984). The areas used for living activities often moved within the site (Fig. 3). Since remains of houses have not been found, it is not certain that the areas were actually inhabited. For convenience, the areas are referred to as occupied areas in this paper. 2.2. Futatsumori The Futatsumori site (Fig. 1) is located at 401450 N, 1411140 E and 25–30 m a.s.l. on the west coast of Ogawara Lake. It is assumed to be the largest shell mound in Aomori Prefecture. The site has been known from the Meiji Era (AD 1868–1912) and many kinds of animal remains and bone implements were excavated during several archaeological researches since then. Many pit dwellings and storage pits were also found on hills surrounding the site. There are many archaeological sites from the Jomon Period near Ogawara Lake including the Tominosawa site where about 500 pit dwellings from the Middle Jomon Period (ca. 4500–3500 BP) (Hatakeyama, 2000) and the Omotedate site where ryukisenmon pottery from ca. 12,000 cal yr BP were found (Odagawa, 2000). Over 80% of archaeological sites from the Incipient to Initial Jomon Period (12,000–7000 BP) in Aomori Prefecture are
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Fig. 2. Map of the Satohama site, Higashimatsushima, Miyagi Prefecture, Japan.
concentrated in this area (Jomon Eiga Seisaku-iinkai, 1996). The region around Ogawara Lake including Futatsumori was one of the more developed areas during the Jomon Period. Ogawara Lake used to be an inland sea and became a bay around 6400 BP (Nitobe, 1975; Jomon Eiga Seisaku-iinkai, 1996). 2.3. Moniwa Nearly 1250 sites from the Palaeolithic to the Jomon Period were found on the Natori River Basin in Miyagi Prefecture. Most of them are located in Taihaku ward, Sendai City. The Moniwa site (Fig. 1) is one of them and is located at 381110 N, 1401510 E on a valley mouth of the Natori River. The site was dated to the Initial to the Final Jomon Period (10,000–2300 BP) and Takada wetland is located 1.5 km to the southwest.
2.5. Juno Juno (Fig. 1) is located at 351550 N, 1391380 E on the Shibakawa lowland in the western part of Omiya City, Saitama Prefecture. The Shibakawa lowland is the biggest valley incising Omiya hill. The site is located on the western rim of the lowland. It was found during construction along the Shibakawa River and an archaeological excavation was conducted by the Saitama Museum in 1979–1980. Because the archaeological remains were found during the construction work, sediment of the top 3 m was lost and research concentrated on the sediment from the Jomon Period. During the excavation, over 500 pieces of pottery shards, poles of buildings, chestnuts, horse chestnuts, walnuts, water chestnuts, etc. were found (Saitama Prefectural Museum, 1982). However, the skin of the horse chestnuts was not opened, and therefore there is no evidence that it was eaten.
2.4. Ondashi 2.6. Sakuramachi Ondashi (Fig. 1) is located at 381010 N, 1401140 E, 212 m a.s.l. and was excavated by the Education Board of the Yamagata Prefecture before the construction of National Road 13 in 1985–1987. This area is the confluence of the Yashio and Yoshino Rivers, and natural levees were made by the old river. Sebari Mountains and Zao Mountains are located to the east and the site is on the northern most part of the Yonezawa basin. Remains of 35 houses were found at the excavation in 1985–1987, but no pit dwellings were found. Pottery, stone implements, lacquer ware, pieces of textile, and cookie-like charred food were also found. Analysis of fatty acids revealed that the cookie-like food was made from chestnuts, walnuts, meat from deer and boar, blood of animals and eggs of birds (Sasaki, 1993).
Sakuramachi site (Fig. 1) is located at 361380 N, 1361500 E on a valley that open to the east in Oyabe city, Toyama Prefecture. It was found during a survey for mapping archaeological sites in Oyabe City in 1979 (Sakuramachihakkutsu-chosadan, 2001). Research in 1986 revealed that the site was used from the Incipient to the Final Jomon Period (12,000–2300 BP). A remnant of a small creek was found in 1988, and wooden structures, wooden tools, animal remains and plant remains were unearthed (Sakuramachi-hakkutsu-chosadan, 2001). Structures of raised floor houses were also found, showing that this type of house existed during the Jomon Period. Most timbers used were from Castanea trees (Education Board of Oyabe City, 2000). Remains of an Aesculus stand were found on
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Fig. 3. Location of the sampling site and occupied area and period at the Satohama site (from a booklet from Jomon Festa in Okumatsushima on October 5, 2002).
a river-bank from the Middle Jomon Period (ca. 4000 BP) (Education Board of Oyabe City, 2000). 3. Materials and methods For the analysis of the Satohama site (Figs. 2 and 3), section samples were taken at almost every 2 cm from the 12th to 14th layers of the excavated grid in the Nishihata area. The layers were identified based on the lithology and cultural remains by the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003). The sampling site is indicated by a star in Fig. 3. The sampling site was very close to the place that Yoshikawa and Yoshikawa (2003) analysed. The lithology is indicated in
Fig. 4. A pollen diagram from the site was also reconstructed using both data from the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003) to illustrate the vegetation change from the Early Jomon Period to the Yayoi Period (7000–1700 BP). From the Futatsumori site, a 17 m core was recovered from a paddy field. It was dated to around 8000 BP at the bottom and around 2500 BP, 5 m from the top (Jomon Eiga Seisaku-iinkai, 1996). Thus, it covers the period from the later half of the Initial to the Final Jomon Period (8000–2300 BP). Samples for pollen analysis were taken at almost every 20 cm from the core. For the analysis at the Moniwa site, section samples for pollen analysis were taken at almost every 10 cm interval at the Moniwa-takada moor. The sediment was peat with sand. At the Ondashi site, a peat layer from the Jomon Period was revealed and was taken from the excavated area. Pollen samples were collected at almost every 1 cm. The samples are from the Early Jomon Period (7000–4500 BP) (Fig. 10). At the Juno site, section samples were taken at almost every 5 cm interval from an excavated grid in March, 1980 and analysed at almost every 10 cm interval. The lithology is shown in Fig. 11. At the Sakuramachi site, section samples were taken from an excavated grid on August 20, 2002. The revealed section was silt with fine sand. The samples were from the Late to Final Jomon Period (3500–2300 BP) based on the archaeological remains. Pretreatment for pollen analysis followed the standard method by Moore et al. (1991). The samples were dried at 60 1C until the weight became constant (typically for 7 days) using a vacuum drying oven (ADVANTEC VO-230). A marker grain method was used in the pollen analysis in order to calculate an absolute pollen concentration in sediments (grains/g) for the Satohama site. The procedure of pollen extraction was as follows: (1) measure dry weight of sediment; (2) put 1 cm3 of marker–water mixture (marker grains: DU PONT, NEM-003); (3) HCl treatment; (4) KOH treatment (10% KOH for 10 min at 90 1C); (5) wash (several times with distilled water); (6) HCl treatment (1% HCl); (7) dense media separation (saturated ZnCl2 solution, 1800 rpm. for 20 min); (8) dehydration (conc. acetic acid); (9) acetolysis treatment (1 part of conc. H2SO4 and 9 parts of acetic unhydride, 90 1C for 3 min); (10) wash (distilled water); (11) mount (100% glycerin) The materials were examined under a light microscope (Nikon BIOPHOTO) at X400 or X600 magnification depending on the sample condition. Pollen was identified, mainly referring to the Japanese pollen collections at the International Research Center for Japanese Studies and based on Palynomorphs of Japanese Plants by Shimakura (1973). Totals of more than 200 pollen grains excluding Alnus, herbaceous and aquatic plants were identified for each sample unless the sample contained extremely small numbers of pollen grains. Charcoal fragments with more
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Fig. 4. Lithology of sections from the Satohama site, Higashimatsushima, Miyagi Prefecture, Japan. J43 and SNH-A/B were adapted from the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003).
than 5 mm in diameter were also counted together with marker grains to estimate the numbers in the samples. The percentage pollen diagram from all sites analysed was constructed. The base number of the percentage value was total arboreal pollen grains excluding Alnus. Alnus, which produces large amount of pollen, often grows in and around wetlands in Japan. Therefore, the local influences from it are often projected to the pollen diagram and other species are underestimated. Therefore, Alnus is excluded from the base number in many cases in Japan (Nakamura, 1969). In this study, calculations were made in the same way for all sites. Using the data from the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa
(2003), a percentage pollen diagram from the Satohama site from the Early Jomon Period to Mediaeval Period was also reconstructed. The pollen concentration diagram from the Satohama site was constructed in terms of number of pollen grains per dry weight of sediment (grains/g). 4. Results 4.1. Pollen analysis 4.1.1. Satohama (Figs. 1–3) The percentage pollen diagram from the Education Board of Naruse Town (1999) and Yoshikawa and
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Fig. 5. Percentage pollen diagram with selected taxa from the Satohama site, Higashimatsushima, Miyagi Prefecture. (After Education Borad of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003).
Yoshikawa (2003) is shown in Fig. 5. A total of six local pollen zones: I; II; III; IV; V; and VI, were identified in the diagram according to the change of pollen assemblages. High percentages of Quercus subgen. Lepidobalanopsis pollen were observed from zones I to II. This indicates the development of secondary forest from human interaction. In zones II and IV, evidence of hansaibai of Castanea trees was detected. Gradual increase of Castanea pollen was seen in zone I in a stable forest of Quercus subgen. Lepidobalanopsis. In zone II, Quercus subgen. Lepidobalanopsis and Castanea pollen contributed to over 80%. Other species almost disappeared. In the early period of zone IV, the percentage of Castanea was around 50%. In a secondary forest without Castanea protection, these high percentages cannot be observed. In zone III, Castanea pollen almost disappeared and Quercus subgen. Lepidobalanopsis pollen decreased. In zone IV, gradual increase of Pinus subgen. Diploxylon and Quercus subgen. Lepidobalanopsis was observed. Zone V is characterized by high percentages of Aesculus pollen. This could be evidence of hansaibai. Percentages of Pinus subgen. Diploxylon were still high. In zone VI, Castanea and Aesculus pollen almost disappeared. A rapid increase of Pinus subgen. Diploxylon and Gramineae pollen was observed. Percentage and concentration pollen diagrams from the 12th, 13th and 14th layers are shown in Fig. 6. Light micrographs of fossil pollen are shown in Fig. 7. The 12th, 13th and 14th layers correspond to zones II and III in Fig. 5 (see Fig. 4). In Fig. 6, two local pollen zones: I
and II, were identified and zone I was subdivided into Ia and Ib. In zone Ia, high percentages of Castanea and Quercus subgen. Lepidobalanopsis pollen were observed. Both percentages and concentrations of Cyperaceae pollen were also high. Both percentages and concentrations of charcoal fragments were not high compared with other zones. This means that human activity was low compared with other periods. In zone Ib, the percentage of Castanea and Quercus subgen. Lepidobalanopsis pollen did not change from the previous zone. Cyperaceae pollen decreased. In contrast, Leguminosae pollen increased drastically. The Leguminosae pollen resembled Lespedeza cyrtobotrya based on Palynomorph of Japanese Plants (Shimakura, 1973). The shape was subprolate, the aperture was oval in shape, the diameter of the aperture was ca. 7 mm and the surface was finely reticulated (Fig. 7-3 and 7-4). Lespedeza is often observed in a disturbed area by human or natural disaster. From this zone, charcoal increased dramatically. In the concentration pollen diagram, most pollen increased, probably due to the change of sedimentation environment. Charcoal fragments concentration also increased. From these data, it is surmised that human interactions became high. Zone II is characterized by the increase of Pinus subgen. Diploxylon pollen and a rapid decrease of Castanea pollen in both the percentage and concentration pollen diagrams. A decrease of Cyperaceae and Leguminosae pollen was also observed. The concentration level of charcoal fragments did not change much although percentages of it increased.
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Fig. 6. Percentages (upper) and concentration (lower) pollen diagram with selected taxa from the Satohama site, Higashimatsushima, Miyagi Prefecture.
Fig. 7. Light micrographs of fossil pollen from the Satohama site. 1: Pinus subgen. Diploxylon type; 2: Castanea type; 3, 4: Legminosae type; 5: Cyperaceae type. Bar ¼ 20 mm.
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Fig. 8. Percentage pollen diagram with selected taxa from the Futatsumori site, Aomori Prefecture.
4.1.2. Futatsumori (Fig. 1) A percentage pollen diagram is shown in Fig. 8. Percentages of Quercus subgen. Lepidobalanopsis were constantly high. Based on the pollen assemblages, four local pollen zones: I–IV, were identified. Zone III was further subdivided into IIIa and IIIb. Quercus subgen. Lepidobalanopsis was dominant in all zones, and low percentages of Castanea pollen were observed in all zones. Aesculus pollen increased in zone III. Zone I is characterized by high percentages of Juglans pollen and low percentages of Fagus pollen. Gramineae and Cyperaceae were also relatively high. The percentages of Castanea were too low to be evidence of hansaibai. Percentages of charcoal fragments became high. Human interaction increased. In zone II, high percentages of Fagus crenata pollen were observed. Secondary forest area might have decreased. Juglans decreased and although percentages were low, Castanea pollen was identified from this zone corresponding with the Early Jomon Period (7000–4500 BP). However, the percentages were not high. Charcoal fragments decreased drastically. In zone III, percentages of F. crenata gradually decreased and Alnus pollen also increased. In the early stage of zone III, extremely high percentages of monoletetype spores were identified. Charcoal and Quercus subgen. Lepidobalanopsis increased, indicating secondary forest development through human interaction. In zone IIIb, Aesculus pollen increased. The highest percentage exceeded 15% during the development of the secondary forest. These high percentages are unusual in natural forests and Aesculus is not an element of secondary forests. This period correspond to the Final Jomon Period (3000–2300 BP). This could be evidence of hansaibai. Zone IV is characterized by high percentages of Gramineae and Cyperaceae pollen which might indicate the start of rice cultivation. The Yayoi culture (2300–1700 BP) might have started from this period.
4.1.3. Moniwa (momowa-takada moor) (Fig. 1) The percentage pollen diagram is shown in Fig. 9. Three local pollen zones: I; II; and III, were identified based on pollen assemblages. Zone III was further subdivided into IIIa and IIIb. Castanea pollen increase was detected in zone III. In zone I, percentages of Cryptomeria and Fallopia japonica pollen were high. F. japonica prefers dry conditions and is often seen in the Pacific Ocean side of the Japanese Archipelago. Percentages of F. crenata are also high, so F. crenata and Cryptomeria forest including F. japonica developed in this area in rather dry conditions. From zones II to III, Quercus subgen, Lepidobalanopsis was dominant. Secondary forest developed, and charcoal increased from zone II. In zone III, an increase of Castanea pollen was observed. It exceeded 15% in a stable secondary forest of Quercus subgen, Lepidobalanopsis. Especially in zone IIIa, Alnus and F. crenata decreased, which might be evidence of hansaibai. However, the activity might not have been as high as that at the Sannai-Maruyama and Kamegaoka sites. 4.1.4. Ondashi (Fig. 1) 14 C data indicated that all samples were from the Early Jomon Period (7000–4500 BP) (Fig. 10). The percentage pollen diagram did not show much change throughout the diagram. High percentages of Quercus subgen. Lepidobalanopsis and Gramineae pollen were observed throughout the samples. Although Castanea pollen was detected, the percentages of Castanea pollen were not high. It was about 5% at maximum. This level is normally observed in secondary forest without Castanea protection. In this case, it is hard to say hansaibai occurred. 4.1.5. Juno (Fig. 1) The percentage pollen diagram is shown in Fig. 11. Based on the pollen assemblages, five local pollen zones:
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Fig. 9. Percentage pollen diagram with selected taxa from the Moniwa-takada Moor, Sendai, Miyagi Prefecture.
Fig. 10. Percentage pollen diagram with selected taxa from the Ondashi site, Yamagata Prefecture.
Fig. 11. Percentage pollen diagram with selected taxa from the Juno site, Saitama Prefecture.
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Fig. 12. Percentage pollen diagram with selected taxa from the Sakuramachi site, Toyama Prefecture.
I–V, were identified. Zone II was further subdivided into zones IIa and IIb. Zone III may correspond to the period from the Early Jomon Period to the Middle Jomon Period (7000–3500 BP) based on the cultural remains. Zone IV is from the Late to Final Jomon Period (3500–2300 BP). Quercus subgen. Lepidobalanopsis was dominant in all zones except zone V. The highest percentage of Castanea and Aesculus pollen was ca. 5%. It is normally observed in a forest without protection. Although both Castanea and Aesculus pollen was detected in all zones, hansaibai of Aesculus cannot be detected. A slight increase of Castanea pollen was observed in zones III and IV. Although it was not high, other taxa, e.g., Ulmus-Zelkova and Celtis-Aphananthe decreased. Artemisia was rarely observed in zone III. It may be considered that Castanea was preserved and undergrowth was trimmed, although not intensely.
4.1.6. Sakuramachi (Fig. 1) Although samples were analysed from the top to the bottom, few pollen grains were detected in the middle of the sections. Pollen grains from three samples around 80 cm and from one sample at 16 cm were counted and calculated for percentage pollen diagram (Fig. 12). Around 80 cm in depth, 7C-2 from the Late Jomon Period (3500–3000 BP), high percentages of Castanea and Aesculus pollen were observed. The percentages of Castanea were about 30% and of Aesculus were about 20%. F. crenata pollen was low and Quercus subgen. Lepidobalanopsis was relatively high in percentage. Protection of both species might have happened in the developed secondary forest. The sample at 16 cm depth from the Final Jomon Period (3000–2300 BP) exhibited low percentages of arboreal pollen. Quercus subgen. Lepidobalanopsis were dominant, but Castanea and Aesculus almost disappeared.
5. Discussion 5.1. Climate and Castanea hansaibai at Satohama Two C. hansaibai periods at the Satohama site were observed from pollen analysis. One was from the Early Jomon Period (7000–4500 BP) (zone II in Fig. 5 and zone I in Fig. 6) and the other was from the Middle Jomon Period (4500–3000 BP) (zone IV in Fig. 5). Fig. 13 shows the percentage pollen diagram with Castanea, Aesculus and Pinus subgen. Diploxylon pollen from the Satohama site and sea level change (Fukusawa, 1998) and the pollen data of Pinus subgen. Haploxylon from Ozegahara Moor (Sakaguchi, 1993). It is generally considered that when the sea level was high, the temperature was high, and when it was low, temperature was low. Pinus subgen. Haploxylon prefers a cold climate and normally grows in a high altitude in Japan. Sakaguchi (1993) considers that when cold climate prevails, the forest area of Pinus becomes larger and the percentage contribution of its pollen becomes high. Therefore, these two results are used as a temperature proxy. Hansaibai of Castanea started during the warm period in the Early Jomon Period (7000–4500 BP). During zone IV, a cold period was observed, but the Castanea stand did not disappear. In the same period, it disappeared at the SannaiMaruyama site (Kitagawa and Yasuda, 2004). This may be ascribed to the higher annual average temperature or warmer winter in this area compared to that in Aomori Prefecture. Cold climate did not influence C. hansaibai at the Satohama site as much as at the Sannai-Maruyama and the Kamegaoka sites. C. hansaibai continued at the Satohama site even in a relatively cold period due to the warmer climate. However, when temperature oscillated and it became severely cold in the Late to the Final Jomon Period (3500–2300 BP), A. hansaibai started. This might have been a safeguard against crop failure. The slight change of climate did not
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Fig. 13. Pollen diagrams from the Satohama site, Higashimatsushima, Miyagi Prefecture with selected taxa: Castanea; Aesculus; and Pinus subgen. Diploxylon, and climate parameters: sea level change: high sea levels indicate lower temperature and low sea levels indicate lower temperature; and percentages of Pinus subgen. Haploxylon: high percentages indicate low temperature and low percentages indicate high temperature; as well as occupied area and period indicated in Fig. 3.
affect C. hansaibai at warmer places, while it was affected at Aomori prefecture because that area was close to the northern limit of Castanea distribution. Climatic change severely influenced the selection of plants in the northern part of Japan, but less influence is expected in the southern parts. 5.2. Sea level and Castanea hansaibai The Satohama site is surrounded by sea. As a result, the living area might be strongly affected by sea level. When sea level was high, the area available for occupation was small. Occupied areas are also indicated in Fig. 13. Hansaibai of Castanea started during the Early Jomon Period (7000–4500 BP) (zone II), but people in Satohama seemed to have ceased hansaibai shortly. The detailed analysis in Fig. 6 also shows the decrease of Castanea at the same phase. During the absence of C. hansaibai (zone III in Figs. 5 and 13), both sea level and percentages of Pinus subgen. Haploxylon indicate a warm climate (Fig. 13). In the early phase of zone III, sea level dropped once and at the same time, percentage of Castanea became high. C. hansaibai is indicated, but unfortunately data were absent in the later phase. During this period, location 3, which is lower in altitude than other locations, appeared to
be occupied area. Although hansaibai of Castanea was observed at the Sannai-Maruyama site during the same period (Kitagawa and Yasuda, 2004), it was not observed at the Satohama site during the period of the highest sea level. The area available for occupation may explain this situation. Fig. 13 indicates the periods when the place was inhabited. Locations 1, 3, 4, and 6 are located very close to the sampling site (Fig. 3) but location 6 is behind a hill. The Daigakoi area, close to the sampling site, was almost always inhabited during the Jomon Period. Locations 1 and 2 were the occupied areas during the Early Jomon Period (7000–4500 BP). Location 2 is distant from the sampling site although 1 is close and is the highest point of the Daigakoi area. Location 3, which is lower in altitude than location 1, was inhabited during the Early Jomon Period (7000–4500 BP) when the sea level dropped. The occupied area was restricted to location 1 in the Daigakoi area during this warm period. Subsequently, when the sea level became lower, the occupied area was shifted to lower places (locations 4 and 6) and Castanea stands appeared. However, Castanea decreased and Aesculus increased when climate became colder (zone V) as observed in the Kamegaoka site.
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Entering the Final Jomon or Yayoi Period, Castanea and Aesculus pollen almost disappeared. Rice cultivation was introduced to this area after this period as Gramineae pollen (Oryza type) increased from this period. 5.3. Occupied areas and places of hansaibai The decrease of Castanea pollen might be related to the shift of the occupied area. Although location 6 (Fig. 3) is close to the sampling site, it is behind a hill. When the Castanea stand was behind the hill, it is expected the percentages of Castanea pollen decreased. Castanea stands might be associated with the occupied area. The former stands of Castanea were abandoned when the areas that were occupied were changed and then established in the new occupied area. Probably the Castanea stand was created on the other side of the hill and Pinus forest expansion occurred near the sampling site. Consequently, Castanea appeared to decrease since the pollen diagram was drawn based on the total arboreal pollen counts. The concentration pollen diagram illustrates the actual situation. Appearance and disappearance of Castanea and Aesculus stands were related not only to climate, but also to the surrounding environment, i.e. sea level change at the Satohama site. Other factors also might influence hansaibai activities. When the distribution of Castanea and A. hansaibai activities are considered, one should be careful to consider the environment of the site. 5.4. Distribution of hansaibai of Castanea and Aesculus trees The sites where hansaibai of Castanea and Aesculus were observed were mapped in Fig. 14. The Tohoku region (the northern part of Honshu Island) and the Hokuriku region (Japan Sea Coast area in Central Japan) were the main
Fig. 14. Jomon archaeological sites with an evidence of Castanea and Aesculus hansaibai (Goto and Tsuji, 2001; Kiyonaga, 1990; Miyamoto et al., 1999; Tsuji, 1989).
distribution areas. In this study, no evidence of hansaibai in Western Japan was detected based on pollen analysis. It is possible that it spread at least to the Tohoku and Hokuriku regions during the Early to Middle Jomon Period (7000–3500 BP). Watamabe (1981) also argued that hansaibai developed in Eastern Japan from the Early Jomon Period to the Middle Jomon Period (7000–3500 BP) that corresponds to this result. Watamabe (1981) also mentioned that large longhouses, with large amounts of nuts preserved in the attic for winter food, were often found along the Japan Sea coastline (Fig. 15). Remains of raisedfloor houses were also found at the Sakuramach site, Toyama Prefecture (Sakuramachi-hakkutsu-chosadan, 2001). That kind of house was usually seen at sites from the Yayoi period for grain preservation because it is good for isolating grain from moisture and heat. It is also suitable for long-term preservation of nuts. It is necessary for people who are living in a snow-accumulation area to preserve a large amount of food for a long winter. In the hansaibai stage, storage structures should be ready for preserving this large amount of foods and a yearly plan of living must have been established. To harvest a large amount of nuts in autumn, hansaibai might have developed in this area. More than half of all sites and the earliest archaeological sites with hansaibai activity are located in the heavy snow area (Fig. 16). Snow accumulation might be a reason why hansaibai developed in the Tohoku and Hokuriku regions. Watamabe (1981) also suggested that the hansaibai developed in Western Japan during the Late Jomon Period (3500–3000 BP), but this discussion should be left until more pollen data are available. The earliest appearance of hansaibai seemed to be in the Hokuriku region and it appeared to spread in the Tohoku region. The Tohoku region, especially Aomori Prefecture
Fig. 15. Snow accumulation and archaeological sites where long house remains were found (Watamabe, 1981).
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seemed to be more active than other areas. The spread to the Kanto region was later than other areas. The earliest sites of agriculture in Japan can be seen in the Hokuriku and the Tohoku region. The grains of millet were found at the Tominosawa site from the Middle Jomon Period (4500–3500 BP) (Education Board of Aomori Prefecture, 1992) and the Kazahari site from the Late Jomon Period (3500–3000 BP) (Crawford, 1992) in Aomori Prefecture is one of the earliest sites of agriculture in Japan (Fig. 17). However, pollen of Fagopyrum was found from an even earlier period, e.g., the Early to Middle Jomon Period (7000–3500 BP) (Fig. 17). It was found at the Junichogata site, Toyama Prefecture from the Early Jomon Period
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(7000–4500 BP) (Yasuda, 1982) and at the Osawa site, Niigata Prefecture from the Middle Jomon Period (4500–3500 BP) (Maeyama, 1990). The cultural influence from the continent cannot be denied. However, the arrival of agriculture to Central Japan other than to the Hokuriku region came much later. The condition of both Western Japan and Eastern Japan is the same in terms of facing the Japan Sea, but agriculture developed in Eastern Japan first, introduced to the Hokuriku and Tohoku regions. Thus, hansaibai techniques and culture including preservation tools became the basis of accepting agriculture.
6. Conclusion
Fig. 16. Snow accumulation and sites where hansaibai activity was detected by pollen analysis.
Hansaibai culture developed due to the climate condition in the Jomon Period and this activity might have influenced the introduction of agriculture. The possibility of active and extensive hansaibai or cultivation of Castanea and Aesculus were detected by pollen analyses from Jomon sites mainly in the Hokuriku and Tohoku region. When Castanea hansaibai was practiced, the stands were made very close to the occupied area. However, regional differences in hansaibai activity might have existed. Most sites analysed exhibited the increase of Castanea and/or Aesculus pollen. The expansion of hansaibai culture in the Hokuriku and Tohoku region was indicated in this study although more data from pollen analyses from Jomon sites were necessary to reveal the expansion and distribution of hansaibai culture. The distribution of hansaibai or cultivation of Castanea and Aesculus is still under investigation. The periods of hansaibai were not continuous. The main factor is thought to be climate variations. Since the period of Jomon culture lasted almost 15,000 years, there were several warm periods and cold periods (see Sakaguchi, 1993; Fukusawa, 1998; Suzuki, 2000; Yasuda, 2002).
Fig. 17. The earliest sites of buckwheat and millet cultivation in Japan.
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Vegetation also changed dramatically (Yasuda, 1974a). Consequently, climate and vegetation must have influenced people’s food gathering activity since the Jomon people strongly depended on plant food (Watanabe, 1974). The results of pollen analyses on the Sannai-Maruyam site and the Kamegaoka site revealed an interesting relationship between temperature and periods of Castanea and Aesculus hansaibai. Castanea stands were made during warm periods and Aesculus stands were made during cold periods (Kitagawa and Yasuda, 2004). However at the Satohama site, where the annual average temperature is 1.2 1C higher than that in Aomori City, temperature drop did not have as much influence on Castanea hansaibai as in Aomori Prefecture. Even in the cold period of the early Middle Jomon Period (ca. 4500 BP), when the Castanea stand disappeared at the Sannai-Maruyama site, it was observed based on the pollen analysis from the Satohama site (Fig. 13). However, the colder climate during the later half of the Middle Jomon Period (ca. 4000–3500 BP) affected it and Aesculus hansaibai started. The average temperature might be related to the degree of influence on hansaibai and there might be little influence of climatic fluctuation in Western Japan. The responses to climatic fluctuation might depend on the temperature in each area. Hansaibai was also restricted by other factors, i.e. water availability and space. A period without a Castanea stand at the Satohama site was detected during a warm period although the stand seemed to grow just before the period. Sea level change may be the cause. Since the Satohama site is on a small island and is surrounded by the sea, the land is susceptible to sea level rise. Evidence that the occupied area was on the top of the hill during the warm period (in a booklet from Jomon Festa in Okumatsushima on October 5, 2002) might imply that the surrounding area might have been inundated during the Jomon sea transgression. There might have been no space to grow Castanea trees around the occupied area. Hansaibai of Castanea and Aesculus was practised by Jomon people using knowledge of plants. They selected kinds of plants for hansaibai and the way of consumption which might be suitable for their environment. It might not be easy to accept the idea of producing unknown food when agriculture was introduced to Japan because it was unpredictable how unfamiliar plants would yield every year for the first time. However, once exposed to the idea, they might easily have accepted it since they had already known how to plan to produce and store for consumption. Distribution of storage structure remains Watamabe, 1981; Sakuramachi-hakkutsu-chosadan, 2001) may indicate the development of a yearly plan for food storage. Storage structures were found mainly in heavy snow areas (Watamabe, 1981). In those areas, it was absolutely necessary that large amounts of food were stored for a long winter. To gain enough food, hansaibai might have started. The introduction of rice and millet agriculture occurred during the Middle to Late Jomon Period
(4500–3000 BP) and the earliest sites were found in the Tohoku region (Crawford, 1992; Education Board of Aomori Prefecture, 1992) and buckwheat introduction in the Hokuriku region was even earlier, during the Early to Middle Jomon Period (7000–3500 BP) (Yasuda, 1974b; Maeyama, 1990). It seemed that hansaibai was first introduced to the Hokuriku region, spread to the Tohoku region and became more active in the Tohoku region than in other areas. Surmising from this evidence, penetration of hansaibai culture encouraged introduction of agriculture and hansaibai and the cycle of nut production became a base for it. Acknowledgements The authors sincerely thank Mr. Hiroki Sugahara at the Historical Museum of Jomon Village Oku-Matsushima, Naruse Town, Miyagi Prefecture. We also thank Ms. Fujiko Suda at the Tohoku University for guiding sites in Tohoku region and suggestions while we were conducting the research. References Crawford, G.W., 1992. Prehistoric plant domestication in East Asia. In: Cowan, C.W., Watoson, P.J. (Eds.), The Origin of Agriculture, An International Perspective. Smithsonian Institute Press, Washington, p. 38. Education Board of Aomori Prefecture, (Ed.), 1992. Tominosawa (2) iseki Hakkuttu Chosa Hokokusho (Excavation Report of Tominosawa 2 Site). Education Board of Aomori Prefecture, Aomori (in Japanese). Education Board of Naruse Town, (Ed.), 1999. Satohama-kaizuka, Nrusecho Bunkazai Chosa Hokokusho, dai-5-shu (Satohama Shell Mound, Research Report of Cultural Treasure in Naruse Town, vol. 5, Education Board of Naruse Town, Naruse Town (in Japanese). Education Board of Oyabe City, (Ed.), 2000. Sakuramachi-iseki (Sakuramachi Site). Oyabe City and Tourism Association in Oyabe City (in Japanese). Fukusawa, H., 1998. Hyogaki iko no kikou no nennen hendo wo yomu (Yearly change of climate after last-glacial). Chikyu 68, 353–360 (in Japanese). Goto, K., Tsuji, S., 2001. Vegetation history since the Early Jomon period at Ooyazawa, Aomori, in the southern part of the Aomori Plain. Japanese Journal of Historic Botany 9, 43–53 (in Japanese with English abstract). Harlan, J.R., 1992. Crops & man, second ed. American Society of Agronomy, Crop Science Society of America, Madison. Hatakeyama, N., 2000. Middle Jomon Period. Bulletin of Aomori Prefectural Archaeological Artifacts Research Center 6, 21–24 (in Japanese). Hori, S., 1959. Kafun-bunseki no seika (results of pollen analysis). In: Shimizu, J. (Ed.), Kamegaoka; A Study of the Kamegaoka Neolithic Site, Aomori Prefecture, Japan. The Mita Historical Society, Keiogijuku University, Tokyo, pp. 147–148 (in Japanese with English summary). Japan Meteorological Agency: /http://www.data.kishou.go.jp/S. Jomon Eiga Seisaku-iinkai, 1996. Ichiman-nen Okoku, Aomori-ken no Jomon Bunka (10 Millenium Kingdom, Jomon Culture in Aomori Prefecture). Jomon Eiga Seisaku-iinkai (video tape in Japanese). Kitagawa, J., Yasuda, Y., 2004. The influence of climatic change on chestnut and horse chestnut preservation around Jomon sites in Northeast Japan with special reference to the Sannai-Maruyama and Kamegaoka sites. Quaternary International 123–125, 89–103.
ARTICLE IN PRESS J. Kitagawa, Y. Yasuda / Quaternary International 184 (2008) 41–55 Kitagawa, J., Nakagawa, T., Fujiki, T., Yamaguchi, K., Yasuda, Y., 2004. Human activity and climate change during the historical period in central upland Japan with reference to forest dynamics and the cultivation of Japanese horse chestnut (Aesculus turbinata). Vegetation History and Archaeobotany 13, 105–113. Kiyonaga, J., 1990. Pollen analysis of Holocene sediments from lowland along the Kashi river, southwestern part of Yokohama, Japan. Daiyonki Kenkyu (The Quaternary Research) 29, 351–360 (in Japanese with English abstract). Maeyama, S., 1990. Makimachi Osawa-seki niokeru Jomon-jidai Chuki Zenyo Shuraku no Shokubutu Riyo (Utilization of plants in Makimachi Osawa site from the early half of the Middle Jomon Period). Makimachi-shi Kenkyu (Study of Makimachi City) IV, 1–20 (in Japanese). Matsumoto, H., 1984. Geomorphological development of Higashimatsushima Bay, Miyagi Prefecture, Japan. Annals of the Tohoku Geographical Association 36, 46–53. Matsuyama, T., 1982. Konomi (Nuts). Hoseidaigaku-Shuppankyoku, Tokyo (in Japanese). Minaki, M., 1994. Enlargement of the fruit size of Castanea crenata Sieb, et Zucc, since the Jomon Period (since ca. 10,000 yBP) in Japan. Japanese Journal of Historical Botany 2, 3–10 (in Japanese with English abstract). Miyamoto, S., Yasuda, Y., Kitagawa, H., Takemura, K., 1999. Palaeoenvironmental changes in the Jakagamiike Moor, Fukui Prefecture, Central Japan, during the past 14,000 years. Japanese Journal of Palynology 45, 1–12. Moore, P.D., Webb, J.A., Collinson, M.E., 1991. Pollen Analysis. Blackwell Scientific Publication, Oxford. Nakamura, J., 1969. Kafunbunseki (Pollen Analysis). Kokonshoin, Tokyo (in Japanese). Nakao, S., 1976. Saibai-shokubutsu no Sekai (The World of Cultivated Plants). Chuokoronsha, Tokyo (in Japanese). Nishida, M., 1981. Man-plant relationships in the Jomon period and emergence of food production. Bulletin of the National Museum of Ethnology 6, 234–255 (in Japanese with English abstract). Nitobe, K., 1975. The geomorphic history of Lake Ogawara. Annals of the Tohoku Geographical Association 27, 25–35 (in Japanese with English abstract). Nitobe, T., 1973. Kafunbunseki ni tuite (Pollen analysis). In: Aomori (Ed.), Education Board of Aomori Prefecture, Kamegaika iseki Hakkutsuchosa Houkokusho, Kamegaoka Baipasu Kankei Maizobunkazai Hakkutsuchosa (Report on Archaeological Excavation of Kamegaoka Site, excavation before the construction of Kamegaoka bypass). Education Board of Aomori Prefecture, Aomori, pp. 166–170 (in Japanese). Odagawa, T., 2000. Incipient Jomon Period. Bulletin of Aomori Prefectural Archaeological Artifacts Research Center 6, 10–12 (in Japanese). Saitama Prefectural Museum (Ed.), 1982. Juno-Deitan-Iseki Hakkutsuchosa Hokokusho -Shizenibutsu-hen- (Research report of Juno archaeological site -natural remains-). Education Board of Saitama Prefecture, Urawa (in Japanese). Sakaguchi, Y., 1993. Kako 8000 nen no kikou-hennka to ningen no rekishi (climatic changes and human history of the past 8000 years). Journal of the Senshu University Research Society 51, 79–113 (in Japanese). Sakuramachi-hakkutsu-chosadan, (Ed.), 2001. Sakuramachi-iseki Chosagaiho (Excavation report from Sakuramachi site). Gakuseisha, Tokyo (in Japanese). Sasaki, Y., 1993. Ondashi-kukki (Ondashi Cookies). In: Shinpan Kodai no Nihon 1 (New edition, Ancient Japan 1). Kadokawa-shoten, Tokyo.
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Sato, Y.-I., 2003. Evidence for Jomon plant cultivation based on DNA analysis of chestnut remains. Senri Ethnological Studies 63, 187–197. Shimakura, M., 1973. Palynomorph of Japanese Plants. Osaka Museum of Natural History, Osaka (in Japanese). Shiosawa, K., 1988. Kuri (Chestnuts). In: Aiga, T. (Ed.), The Grand Dictionary of Horticulture 2. Shogakukan, Tokyo, pp. 145–149 (in Japanese). Suzuki, H., 2000. Kikohenka to ningen–ichi-man-nen no rekishi-(Climate and humans-the history of 10,000 years-). Taimeido, Tokyo (in Japanese). Tsuji, S., 1989. Paleoenvironmental reconstruction in the dissected valley in Prehistory: Holocene paleoenvironment at the Akayama site in Kawaguchi, Central Kanto Plain, Japan. Daiyonki Kenkyu (The Quaternary Research) 27, 331–356 (in Japanese with English abstract). Tsutsumi, T., 2002. Origin of pottery and human strategies for adaptation during the termination of the Last-Glacial period in the Japanese Archipelago. In: Yasuda, Y., Shinde, V. (Eds.), Origins of Pottery and Agriculture. Lustra Press and Rolibook, New Delhi, pp. 241–262. Watamabe, M., 1981. Jomon-jidai niokeru bunatai bunnka (Beech forest culture during Jomon Period). Chiri (Geography) 26 (4), 39–46 (in Japanese). Watanabe, M., 1974. Various patterns of man’s adaptation to the natural environments in Jomon age. Daiyonki Kenkyu (The Quaternary Research) 13, 160–167 (in Japanese with English abstract). Yamamoto, T., Matsui, A., 1988. Dictionary of Japanese Archaeology. Nara National Cultural Properties Research Institute, Nara. Yamamoto, T., Sakai, A., 1977. Freezing resistance of chestnuts. Journal of Japan Forest Science 59, 360–367 (in Japanese with English abstract). Yasuda, Y., 1974a. Palynology and archaeology since the Late Glacial age in Japan. Daiyonki Kenkyu (The Quaternary Research) 13, 106–134 (in Japanese with English abstract). Yasuda, Y., 1974b. Kafunbunseki (Pollen Analysis). In: Education Board of Fukui Prefecture, (Ed.), Torihama-kaizuka (Torihama Shell Mound). Education Board of Fukui Prefecture, pp. 176–196 (in Japanese) Yasuda, Y., 1982. Kafunbunseki kara mita Toyama-wan engan no Jomon zennki no Iseki (Early Jomon sites around Toyama Bay seen from the aspect of pollen analysis). In: Education Board of Daimon Town, (Ed.), Koizumi-iseki (Koizumi site). Education Board of Daimon Town, Daimon-cho, pp. 99–108 (in Japanese). Yasuda, Y., 1989. Kafunbunseki ni tsuite (Pollen analysis). In: Education Board of Mie Prefecture, (Ed.), Uenoshi Ouchi, Kitaboriike-iseki hakkutsuchosagaiyo III (Excavation of Kitaboriike Archaeological site, Ouchi, Ueno City III). Education Board of Mie Prefecture, Ueno (in Japanese). Yasuda, Y., 1995. Kuribayashi ga sasaeta kodona bunnka (highly developed culture supported by chestnut stands). In: Umehara, T., Yasuda, Y. (Eds.), Jomon Bunmei no Hakken (Discovery of Jomon Civilization). PHP Kenkyusho, Tokyo, pp. 118–153 (in Japanese). Yasuda, Y., 2002. Kodai-bunmei no Kobo (Rise and fall of ancient civilizations). Gakushu-kenkyu-sha, Tokyo (in Japanese). Yokoi, M., 1989. Tochinoki-zoku (Genus Aesculus). In: Aiga, T. (Ed.), The Grand Dictionary of Horticulture 3. Shogakukan, Tokyo, pp. 390–393 (in Japanese). Yoshikawa, A., Yoshikawa, J., 2003. Satohama-kaizuka Nishihata-kitachiten ni okeru Jomon-jidai-zenki no shokubutsu-kaseki-gun (Plant fossil from Nishihata North point at Satohama shell mound during the early Jomon Period). In: Ancient Forest Research, (Ed.), Satohamakaizuka Nishihata-kita-chiten no shizenkagaku-bunseki (Natural scientific analysis on Nishihata North point at Satohama shell mound). Naruse Town, pp. 1–12 (in Japanese).
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Development and distribution of Castanea and Aesculus culture during the Jomon Period in Japan Junko Kitagawa, Yoshinori Yasuda International Research Center for Japanese Studies, 3-2 Oeyama-cho, Goryo, Nishikyo-ku, Kyoto 610-1192, Japan Available online 11 September 2007
Abstract Castanea and Aesculus trees were protected for consumption of nuts as food during the Jomon Period. Climatic factors affected the selection of kinds of consumed nuts. Castanea was mainly consumed during warm periods and Aesculus was consumed during cold periods. However, this could have been a regional phenomenon in northern Japan. It is possible that in southern warmer areas Castanea either might be protected constantly, or the protection of these plants was not necessary because forest productivity in the southern area is greater than that of the northern area. To understand the influence of temperature on Castanea hansaibai, pollen analysis was conducted at the Satohama site. In addition, the distribution of the intermediate stage between wild and domestication (hansaibai) during the Jomon Period was studied based on pollen analyses. At the Satohama site, protection of Castanea started during the warm period in the Early Jomon Period (7000–4500 years BP) and continued to be observed during the next cold period. The Tohoku region (the northern part of Honshu Island) and the Hokuriku region (Japan Sea Coast area in Central Japan) was the main distribution area. In this study, no evidence of the protection of either species in Western Japan was detected. Climate and the necessity for large amounts of food preservation for winter might influence this activity. r 2007 Elsevier Ltd and INQUA. All rights reserved.
1. Introduction The Jomon Period started during the final part of the Pleistocene, about 16,000 BP when the first pottery in Japan appeared (Tsutsumi, 2002). It was the end of the Ice Age and climate warming had started. Deciduous broadleaved forest was expanding to the north. The Jomon Culture developed using abundant resources in the deciduous forest and gathering was an important activity to gain food. Human interaction with forests resulted in the creation of secondary forests in which Quercus subgen. Lepidobalanopsis is dominant in Honshu Island. Among species in secondary forests, the Jomon people selected and preserved plants which were useful for them. By keeping the forest in a constant condition, a stable food supply could be gained. Primitive woodland management started. A plant utilisation procedure, the intermediate stage between wild and domesticated, was developed. At this stage, human beings are not involved in planting seeds Corresponding author.
E-mail address: [email protected] (J. Kitagawa).
intentionally, but extensive stands develop by protecting trees from cutting. Nakao (1976) coined a word, hansaibai (han and saibai, i.e. half and cultivation, respectively), taking examples; e.g., wild rice in North America, Pyrus ussuriensis in North Korea and para gum in Amazonia. Harlan (1992) also described the intermediate stage. The main techniques are bringing seeds to the villages, protecting them from cutting, and owning trees. In the hansaibai phase, human beings are involved neither in planting seeds intentionally nor in reproduction. Protection and preservation are the techniques. It is easy to imagine that people selectively preserved or grew Castanea and Aesculus near the settlement areas to get enough food, since growing chestnuts and horse chestnuts is not difficult (Nishida, 1981; Yokoi, 1989). Castanea crenata and Aesculus turbinata are woody plants. Both have been possibly cultivated and utilised since the Jomon Period (Nakao, 1976; Minaki, 1994; Yasuda, 1995; Sato, 2003). However, the methods might be very primitive. Until recently, the selective protection of these trees, especially Aesculus trees was observed (Matsuyama, 1982; Kitagawa et al., 2004).
1040-6182/$ - see front matter r 2007 Elsevier Ltd and INQUA. All rights reserved. doi:10.1016/j.quaint.2007.09.014
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At Sannai-Maruyama site and Kamegaoka site, hansaibai of Castanea and Aesculus is suggested by pollen analysis (Hori, 1959; Nitobe, 1973; Yasuda, 1995; Kitagawa and Yasuda, 2004) and the relationship between climate and hansaibai of Castanea trees and Aesculus trees in Japan was revealed (Kitagawa and Yasuda, 2004). However, this could have been a regional phenomenon because both the Sannai-Maruyama site and the Kamegaoka site are located in Aomori Prefecture, near the northern limit of Castanea distribution. Even though large amounts of chestnuts and horse chestnuts were yielded in other areas, it is possible that those nuts were gathered from far places. The Kitaboriike site in Mie Prefecture from the Yayoi Period may be a good example (Yasuda, 1989) where pollen analysis did not indicate the possibility of hansaibai of Aesculus at the site. However, the Satohama site is an example of the opposite situation. Although few chestnut remains were detected, high percentages of Castanea pollen, which might indicate hansaibai activity, were observed (Education Board of Naruse Town, 1999; Yoshikawa and Yoshikawa, 2003). It is important to reveal what conditions made the difference for hansaibai activity. A possible cause is temperature since Castanea trees are susceptible to disease during cold periods (Shiosawa, 1988). Branches are also harmed by low temperatures, and tolerate 510 1C in the early winter, 1522 1C during the coldest period and 36 1C in the early spring (Yamamoto and Sakai, 1977). The coldest temperature recorded in Aomori is 18.7 1C (on February 20, 1945: Japan Meteorological Agency). This indicates that Aomori might be beyond the northern limit of Castanea growing during the cold period. Although alternation of Castanea and Aesculus hansaibai was observed in Aomori prefecture, different phenomena may be seen in warmer places. To understand the influence of temperature on Castanea hansaibai, pollen analysis was conducted at the Satohama site where the lowest recorded temperature is 9.3 1C (February 7, 1984; Japan Meteorological Agency), as well as five other sites (Futatsumori site in Aomori Prefecture; Moniwa site in Miyagi Prefecture; Ondashi site in Yamagata Prefecture; Juno site in Saitama Prefecture; and Sakuramachi site in Toyama Prefecture) (Fig. 1). In addition to it, the sites where hansaibai activity is detected, including previous studies, are plotted on a map to show the distribution of hansaibai of both trees. In this paper, calendar years for each period of the Jomon culture are provided based on Dictionary of Japanese Archaeology (Yamamoto and Matsui, 1988), although slight differences exist among sites due to difference of the timing of cultural development. 2. Research site descriptions 2.1. Satohama Over 120 shell mounds have been identified around Higashimatsushima Bay. The Satohama site (Figs. 1 and 2)
Fig. 1. Analysed Jomon archaeological sites. Dots indicate the analysed sites.
is located at 381200 N, 1411080 E on Miyakojima Island. The circumference of the island is about 15 km and the site has been measured about 640 m from east to west and about 200 m from north to south. The annual average temperature in Shiogama close to the Satohama site was 11.3 1C in 2002 which was 1.2 1C higher than that of Aomori City (Japan Meteorological Agency). Miyakojima Island used to be connected to Honshu Island in the early Holocene, but was separated around 7500 BP due to the marine transgression, and the sea level reached its present position around 6800 BP (Matsumoto, 1984). The areas used for living activities often moved within the site (Fig. 3). Since remains of houses have not been found, it is not certain that the areas were actually inhabited. For convenience, the areas are referred to as occupied areas in this paper. 2.2. Futatsumori The Futatsumori site (Fig. 1) is located at 401450 N, 1411140 E and 25–30 m a.s.l. on the west coast of Ogawara Lake. It is assumed to be the largest shell mound in Aomori Prefecture. The site has been known from the Meiji Era (AD 1868–1912) and many kinds of animal remains and bone implements were excavated during several archaeological researches since then. Many pit dwellings and storage pits were also found on hills surrounding the site. There are many archaeological sites from the Jomon Period near Ogawara Lake including the Tominosawa site where about 500 pit dwellings from the Middle Jomon Period (ca. 4500–3500 BP) (Hatakeyama, 2000) and the Omotedate site where ryukisenmon pottery from ca. 12,000 cal yr BP were found (Odagawa, 2000). Over 80% of archaeological sites from the Incipient to Initial Jomon Period (12,000–7000 BP) in Aomori Prefecture are
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Fig. 2. Map of the Satohama site, Higashimatsushima, Miyagi Prefecture, Japan.
concentrated in this area (Jomon Eiga Seisaku-iinkai, 1996). The region around Ogawara Lake including Futatsumori was one of the more developed areas during the Jomon Period. Ogawara Lake used to be an inland sea and became a bay around 6400 BP (Nitobe, 1975; Jomon Eiga Seisaku-iinkai, 1996). 2.3. Moniwa Nearly 1250 sites from the Palaeolithic to the Jomon Period were found on the Natori River Basin in Miyagi Prefecture. Most of them are located in Taihaku ward, Sendai City. The Moniwa site (Fig. 1) is one of them and is located at 381110 N, 1401510 E on a valley mouth of the Natori River. The site was dated to the Initial to the Final Jomon Period (10,000–2300 BP) and Takada wetland is located 1.5 km to the southwest.
2.5. Juno Juno (Fig. 1) is located at 351550 N, 1391380 E on the Shibakawa lowland in the western part of Omiya City, Saitama Prefecture. The Shibakawa lowland is the biggest valley incising Omiya hill. The site is located on the western rim of the lowland. It was found during construction along the Shibakawa River and an archaeological excavation was conducted by the Saitama Museum in 1979–1980. Because the archaeological remains were found during the construction work, sediment of the top 3 m was lost and research concentrated on the sediment from the Jomon Period. During the excavation, over 500 pieces of pottery shards, poles of buildings, chestnuts, horse chestnuts, walnuts, water chestnuts, etc. were found (Saitama Prefectural Museum, 1982). However, the skin of the horse chestnuts was not opened, and therefore there is no evidence that it was eaten.
2.4. Ondashi 2.6. Sakuramachi Ondashi (Fig. 1) is located at 381010 N, 1401140 E, 212 m a.s.l. and was excavated by the Education Board of the Yamagata Prefecture before the construction of National Road 13 in 1985–1987. This area is the confluence of the Yashio and Yoshino Rivers, and natural levees were made by the old river. Sebari Mountains and Zao Mountains are located to the east and the site is on the northern most part of the Yonezawa basin. Remains of 35 houses were found at the excavation in 1985–1987, but no pit dwellings were found. Pottery, stone implements, lacquer ware, pieces of textile, and cookie-like charred food were also found. Analysis of fatty acids revealed that the cookie-like food was made from chestnuts, walnuts, meat from deer and boar, blood of animals and eggs of birds (Sasaki, 1993).
Sakuramachi site (Fig. 1) is located at 361380 N, 1361500 E on a valley that open to the east in Oyabe city, Toyama Prefecture. It was found during a survey for mapping archaeological sites in Oyabe City in 1979 (Sakuramachihakkutsu-chosadan, 2001). Research in 1986 revealed that the site was used from the Incipient to the Final Jomon Period (12,000–2300 BP). A remnant of a small creek was found in 1988, and wooden structures, wooden tools, animal remains and plant remains were unearthed (Sakuramachi-hakkutsu-chosadan, 2001). Structures of raised floor houses were also found, showing that this type of house existed during the Jomon Period. Most timbers used were from Castanea trees (Education Board of Oyabe City, 2000). Remains of an Aesculus stand were found on
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Fig. 3. Location of the sampling site and occupied area and period at the Satohama site (from a booklet from Jomon Festa in Okumatsushima on October 5, 2002).
a river-bank from the Middle Jomon Period (ca. 4000 BP) (Education Board of Oyabe City, 2000). 3. Materials and methods For the analysis of the Satohama site (Figs. 2 and 3), section samples were taken at almost every 2 cm from the 12th to 14th layers of the excavated grid in the Nishihata area. The layers were identified based on the lithology and cultural remains by the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003). The sampling site is indicated by a star in Fig. 3. The sampling site was very close to the place that Yoshikawa and Yoshikawa (2003) analysed. The lithology is indicated in
Fig. 4. A pollen diagram from the site was also reconstructed using both data from the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003) to illustrate the vegetation change from the Early Jomon Period to the Yayoi Period (7000–1700 BP). From the Futatsumori site, a 17 m core was recovered from a paddy field. It was dated to around 8000 BP at the bottom and around 2500 BP, 5 m from the top (Jomon Eiga Seisaku-iinkai, 1996). Thus, it covers the period from the later half of the Initial to the Final Jomon Period (8000–2300 BP). Samples for pollen analysis were taken at almost every 20 cm from the core. For the analysis at the Moniwa site, section samples for pollen analysis were taken at almost every 10 cm interval at the Moniwa-takada moor. The sediment was peat with sand. At the Ondashi site, a peat layer from the Jomon Period was revealed and was taken from the excavated area. Pollen samples were collected at almost every 1 cm. The samples are from the Early Jomon Period (7000–4500 BP) (Fig. 10). At the Juno site, section samples were taken at almost every 5 cm interval from an excavated grid in March, 1980 and analysed at almost every 10 cm interval. The lithology is shown in Fig. 11. At the Sakuramachi site, section samples were taken from an excavated grid on August 20, 2002. The revealed section was silt with fine sand. The samples were from the Late to Final Jomon Period (3500–2300 BP) based on the archaeological remains. Pretreatment for pollen analysis followed the standard method by Moore et al. (1991). The samples were dried at 60 1C until the weight became constant (typically for 7 days) using a vacuum drying oven (ADVANTEC VO-230). A marker grain method was used in the pollen analysis in order to calculate an absolute pollen concentration in sediments (grains/g) for the Satohama site. The procedure of pollen extraction was as follows: (1) measure dry weight of sediment; (2) put 1 cm3 of marker–water mixture (marker grains: DU PONT, NEM-003); (3) HCl treatment; (4) KOH treatment (10% KOH for 10 min at 90 1C); (5) wash (several times with distilled water); (6) HCl treatment (1% HCl); (7) dense media separation (saturated ZnCl2 solution, 1800 rpm. for 20 min); (8) dehydration (conc. acetic acid); (9) acetolysis treatment (1 part of conc. H2SO4 and 9 parts of acetic unhydride, 90 1C for 3 min); (10) wash (distilled water); (11) mount (100% glycerin) The materials were examined under a light microscope (Nikon BIOPHOTO) at X400 or X600 magnification depending on the sample condition. Pollen was identified, mainly referring to the Japanese pollen collections at the International Research Center for Japanese Studies and based on Palynomorphs of Japanese Plants by Shimakura (1973). Totals of more than 200 pollen grains excluding Alnus, herbaceous and aquatic plants were identified for each sample unless the sample contained extremely small numbers of pollen grains. Charcoal fragments with more
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Fig. 4. Lithology of sections from the Satohama site, Higashimatsushima, Miyagi Prefecture, Japan. J43 and SNH-A/B were adapted from the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003).
than 5 mm in diameter were also counted together with marker grains to estimate the numbers in the samples. The percentage pollen diagram from all sites analysed was constructed. The base number of the percentage value was total arboreal pollen grains excluding Alnus. Alnus, which produces large amount of pollen, often grows in and around wetlands in Japan. Therefore, the local influences from it are often projected to the pollen diagram and other species are underestimated. Therefore, Alnus is excluded from the base number in many cases in Japan (Nakamura, 1969). In this study, calculations were made in the same way for all sites. Using the data from the Education Board of Naruse Town (1999) and Yoshikawa and Yoshikawa
(2003), a percentage pollen diagram from the Satohama site from the Early Jomon Period to Mediaeval Period was also reconstructed. The pollen concentration diagram from the Satohama site was constructed in terms of number of pollen grains per dry weight of sediment (grains/g). 4. Results 4.1. Pollen analysis 4.1.1. Satohama (Figs. 1–3) The percentage pollen diagram from the Education Board of Naruse Town (1999) and Yoshikawa and
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Fig. 5. Percentage pollen diagram with selected taxa from the Satohama site, Higashimatsushima, Miyagi Prefecture. (After Education Borad of Naruse Town (1999) and Yoshikawa and Yoshikawa (2003).
Yoshikawa (2003) is shown in Fig. 5. A total of six local pollen zones: I; II; III; IV; V; and VI, were identified in the diagram according to the change of pollen assemblages. High percentages of Quercus subgen. Lepidobalanopsis pollen were observed from zones I to II. This indicates the development of secondary forest from human interaction. In zones II and IV, evidence of hansaibai of Castanea trees was detected. Gradual increase of Castanea pollen was seen in zone I in a stable forest of Quercus subgen. Lepidobalanopsis. In zone II, Quercus subgen. Lepidobalanopsis and Castanea pollen contributed to over 80%. Other species almost disappeared. In the early period of zone IV, the percentage of Castanea was around 50%. In a secondary forest without Castanea protection, these high percentages cannot be observed. In zone III, Castanea pollen almost disappeared and Quercus subgen. Lepidobalanopsis pollen decreased. In zone IV, gradual increase of Pinus subgen. Diploxylon and Quercus subgen. Lepidobalanopsis was observed. Zone V is characterized by high percentages of Aesculus pollen. This could be evidence of hansaibai. Percentages of Pinus subgen. Diploxylon were still high. In zone VI, Castanea and Aesculus pollen almost disappeared. A rapid increase of Pinus subgen. Diploxylon and Gramineae pollen was observed. Percentage and concentration pollen diagrams from the 12th, 13th and 14th layers are shown in Fig. 6. Light micrographs of fossil pollen are shown in Fig. 7. The 12th, 13th and 14th layers correspond to zones II and III in Fig. 5 (see Fig. 4). In Fig. 6, two local pollen zones: I
and II, were identified and zone I was subdivided into Ia and Ib. In zone Ia, high percentages of Castanea and Quercus subgen. Lepidobalanopsis pollen were observed. Both percentages and concentrations of Cyperaceae pollen were also high. Both percentages and concentrations of charcoal fragments were not high compared with other zones. This means that human activity was low compared with other periods. In zone Ib, the percentage of Castanea and Quercus subgen. Lepidobalanopsis pollen did not change from the previous zone. Cyperaceae pollen decreased. In contrast, Leguminosae pollen increased drastically. The Leguminosae pollen resembled Lespedeza cyrtobotrya based on Palynomorph of Japanese Plants (Shimakura, 1973). The shape was subprolate, the aperture was oval in shape, the diameter of the aperture was ca. 7 mm and the surface was finely reticulated (Fig. 7-3 and 7-4). Lespedeza is often observed in a disturbed area by human or natural disaster. From this zone, charcoal increased dramatically. In the concentration pollen diagram, most pollen increased, probably due to the change of sedimentation environment. Charcoal fragments concentration also increased. From these data, it is surmised that human interactions became high. Zone II is characterized by the increase of Pinus subgen. Diploxylon pollen and a rapid decrease of Castanea pollen in both the percentage and concentration pollen diagrams. A decrease of Cyperaceae and Leguminosae pollen was also observed. The concentration level of charcoal fragments did not change much although percentages of it increased.
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Fig. 6. Percentages (upper) and concentration (lower) pollen diagram with selected taxa from the Satohama site, Higashimatsushima, Miyagi Prefecture.
Fig. 7. Light micrographs of fossil pollen from the Satohama site. 1: Pinus subgen. Diploxylon type; 2: Castanea type; 3, 4: Legminosae type; 5: Cyperaceae type. Bar ¼ 20 mm.
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Fig. 8. Percentage pollen diagram with selected taxa from the Futatsumori site, Aomori Prefecture.
4.1.2. Futatsumori (Fig. 1) A percentage pollen diagram is shown in Fig. 8. Percentages of Quercus subgen. Lepidobalanopsis were constantly high. Based on the pollen assemblages, four local pollen zones: I–IV, were identified. Zone III was further subdivided into IIIa and IIIb. Quercus subgen. Lepidobalanopsis was dominant in all zones, and low percentages of Castanea pollen were observed in all zones. Aesculus pollen increased in zone III. Zone I is characterized by high percentages of Juglans pollen and low percentages of Fagus pollen. Gramineae and Cyperaceae were also relatively high. The percentages of Castanea were too low to be evidence of hansaibai. Percentages of charcoal fragments became high. Human interaction increased. In zone II, high percentages of Fagus crenata pollen were observed. Secondary forest area might have decreased. Juglans decreased and although percentages were low, Castanea pollen was identified from this zone corresponding with the Early Jomon Period (7000–4500 BP). However, the percentages were not high. Charcoal fragments decreased drastically. In zone III, percentages of F. crenata gradually decreased and Alnus pollen also increased. In the early stage of zone III, extremely high percentages of monoletetype spores were identified. Charcoal and Quercus subgen. Lepidobalanopsis increased, indicating secondary forest development through human interaction. In zone IIIb, Aesculus pollen increased. The highest percentage exceeded 15% during the development of the secondary forest. These high percentages are unusual in natural forests and Aesculus is not an element of secondary forests. This period correspond to the Final Jomon Period (3000–2300 BP). This could be evidence of hansaibai. Zone IV is characterized by high percentages of Gramineae and Cyperaceae pollen which might indicate the start of rice cultivation. The Yayoi culture (2300–1700 BP) might have started from this period.
4.1.3. Moniwa (momowa-takada moor) (Fig. 1) The percentage pollen diagram is shown in Fig. 9. Three local pollen zones: I; II; and III, were identified based on pollen assemblages. Zone III was further subdivided into IIIa and IIIb. Castanea pollen increase was detected in zone III. In zone I, percentages of Cryptomeria and Fallopia japonica pollen were high. F. japonica prefers dry conditions and is often seen in the Pacific Ocean side of the Japanese Archipelago. Percentages of F. crenata are also high, so F. crenata and Cryptomeria forest including F. japonica developed in this area in rather dry conditions. From zones II to III, Quercus subgen, Lepidobalanopsis was dominant. Secondary forest developed, and charcoal increased from zone II. In zone III, an increase of Castanea pollen was observed. It exceeded 15% in a stable secondary forest of Quercus subgen, Lepidobalanopsis. Especially in zone IIIa, Alnus and F. crenata decreased, which might be evidence of hansaibai. However, the activity might not have been as high as that at the Sannai-Maruyama and Kamegaoka sites. 4.1.4. Ondashi (Fig. 1) 14 C data indicated that all samples were from the Early Jomon Period (7000–4500 BP) (Fig. 10). The percentage pollen diagram did not show much change throughout the diagram. High percentages of Quercus subgen. Lepidobalanopsis and Gramineae pollen were observed throughout the samples. Although Castanea pollen was detected, the percentages of Castanea pollen were not high. It was about 5% at maximum. This level is normally observed in secondary forest without Castanea protection. In this case, it is hard to say hansaibai occurred. 4.1.5. Juno (Fig. 1) The percentage pollen diagram is shown in Fig. 11. Based on the pollen assemblages, five local pollen zones:
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Fig. 9. Percentage pollen diagram with selected taxa from the Moniwa-takada Moor, Sendai, Miyagi Prefecture.
Fig. 10. Percentage pollen diagram with selected taxa from the Ondashi site, Yamagata Prefecture.
Fig. 11. Percentage pollen diagram with selected taxa from the Juno site, Saitama Prefecture.
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Fig. 12. Percentage pollen diagram with selected taxa from the Sakuramachi site, Toyama Prefecture.
I–V, were identified. Zone II was further subdivided into zones IIa and IIb. Zone III may correspond to the period from the Early Jomon Period to the Middle Jomon Period (7000–3500 BP) based on the cultural remains. Zone IV is from the Late to Final Jomon Period (3500–2300 BP). Quercus subgen. Lepidobalanopsis was dominant in all zones except zone V. The highest percentage of Castanea and Aesculus pollen was ca. 5%. It is normally observed in a forest without protection. Although both Castanea and Aesculus pollen was detected in all zones, hansaibai of Aesculus cannot be detected. A slight increase of Castanea pollen was observed in zones III and IV. Although it was not high, other taxa, e.g., Ulmus-Zelkova and Celtis-Aphananthe decreased. Artemisia was rarely observed in zone III. It may be considered that Castanea was preserved and undergrowth was trimmed, although not intensely.
4.1.6. Sakuramachi (Fig. 1) Although samples were analysed from the top to the bottom, few pollen grains were detected in the middle of the sections. Pollen grains from three samples around 80 cm and from one sample at 16 cm were counted and calculated for percentage pollen diagram (Fig. 12). Around 80 cm in depth, 7C-2 from the Late Jomon Period (3500–3000 BP), high percentages of Castanea and Aesculus pollen were observed. The percentages of Castanea were about 30% and of Aesculus were about 20%. F. crenata pollen was low and Quercus subgen. Lepidobalanopsis was relatively high in percentage. Protection of both species might have happened in the developed secondary forest. The sample at 16 cm depth from the Final Jomon Period (3000–2300 BP) exhibited low percentages of arboreal pollen. Quercus subgen. Lepidobalanopsis were dominant, but Castanea and Aesculus almost disappeared.
5. Discussion 5.1. Climate and Castanea hansaibai at Satohama Two C. hansaibai periods at the Satohama site were observed from pollen analysis. One was from the Early Jomon Period (7000–4500 BP) (zone II in Fig. 5 and zone I in Fig. 6) and the other was from the Middle Jomon Period (4500–3000 BP) (zone IV in Fig. 5). Fig. 13 shows the percentage pollen diagram with Castanea, Aesculus and Pinus subgen. Diploxylon pollen from the Satohama site and sea level change (Fukusawa, 1998) and the pollen data of Pinus subgen. Haploxylon from Ozegahara Moor (Sakaguchi, 1993). It is generally considered that when the sea level was high, the temperature was high, and when it was low, temperature was low. Pinus subgen. Haploxylon prefers a cold climate and normally grows in a high altitude in Japan. Sakaguchi (1993) considers that when cold climate prevails, the forest area of Pinus becomes larger and the percentage contribution of its pollen becomes high. Therefore, these two results are used as a temperature proxy. Hansaibai of Castanea started during the warm period in the Early Jomon Period (7000–4500 BP). During zone IV, a cold period was observed, but the Castanea stand did not disappear. In the same period, it disappeared at the SannaiMaruyama site (Kitagawa and Yasuda, 2004). This may be ascribed to the higher annual average temperature or warmer winter in this area compared to that in Aomori Prefecture. Cold climate did not influence C. hansaibai at the Satohama site as much as at the Sannai-Maruyama and the Kamegaoka sites. C. hansaibai continued at the Satohama site even in a relatively cold period due to the warmer climate. However, when temperature oscillated and it became severely cold in the Late to the Final Jomon Period (3500–2300 BP), A. hansaibai started. This might have been a safeguard against crop failure. The slight change of climate did not
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Fig. 13. Pollen diagrams from the Satohama site, Higashimatsushima, Miyagi Prefecture with selected taxa: Castanea; Aesculus; and Pinus subgen. Diploxylon, and climate parameters: sea level change: high sea levels indicate lower temperature and low sea levels indicate lower temperature; and percentages of Pinus subgen. Haploxylon: high percentages indicate low temperature and low percentages indicate high temperature; as well as occupied area and period indicated in Fig. 3.
affect C. hansaibai at warmer places, while it was affected at Aomori prefecture because that area was close to the northern limit of Castanea distribution. Climatic change severely influenced the selection of plants in the northern part of Japan, but less influence is expected in the southern parts. 5.2. Sea level and Castanea hansaibai The Satohama site is surrounded by sea. As a result, the living area might be strongly affected by sea level. When sea level was high, the area available for occupation was small. Occupied areas are also indicated in Fig. 13. Hansaibai of Castanea started during the Early Jomon Period (7000–4500 BP) (zone II), but people in Satohama seemed to have ceased hansaibai shortly. The detailed analysis in Fig. 6 also shows the decrease of Castanea at the same phase. During the absence of C. hansaibai (zone III in Figs. 5 and 13), both sea level and percentages of Pinus subgen. Haploxylon indicate a warm climate (Fig. 13). In the early phase of zone III, sea level dropped once and at the same time, percentage of Castanea became high. C. hansaibai is indicated, but unfortunately data were absent in the later phase. During this period, location 3, which is lower in altitude than other locations, appeared to
be occupied area. Although hansaibai of Castanea was observed at the Sannai-Maruyama site during the same period (Kitagawa and Yasuda, 2004), it was not observed at the Satohama site during the period of the highest sea level. The area available for occupation may explain this situation. Fig. 13 indicates the periods when the place was inhabited. Locations 1, 3, 4, and 6 are located very close to the sampling site (Fig. 3) but location 6 is behind a hill. The Daigakoi area, close to the sampling site, was almost always inhabited during the Jomon Period. Locations 1 and 2 were the occupied areas during the Early Jomon Period (7000–4500 BP). Location 2 is distant from the sampling site although 1 is close and is the highest point of the Daigakoi area. Location 3, which is lower in altitude than location 1, was inhabited during the Early Jomon Period (7000–4500 BP) when the sea level dropped. The occupied area was restricted to location 1 in the Daigakoi area during this warm period. Subsequently, when the sea level became lower, the occupied area was shifted to lower places (locations 4 and 6) and Castanea stands appeared. However, Castanea decreased and Aesculus increased when climate became colder (zone V) as observed in the Kamegaoka site.
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Entering the Final Jomon or Yayoi Period, Castanea and Aesculus pollen almost disappeared. Rice cultivation was introduced to this area after this period as Gramineae pollen (Oryza type) increased from this period. 5.3. Occupied areas and places of hansaibai The decrease of Castanea pollen might be related to the shift of the occupied area. Although location 6 (Fig. 3) is close to the sampling site, it is behind a hill. When the Castanea stand was behind the hill, it is expected the percentages of Castanea pollen decreased. Castanea stands might be associated with the occupied area. The former stands of Castanea were abandoned when the areas that were occupied were changed and then established in the new occupied area. Probably the Castanea stand was created on the other side of the hill and Pinus forest expansion occurred near the sampling site. Consequently, Castanea appeared to decrease since the pollen diagram was drawn based on the total arboreal pollen counts. The concentration pollen diagram illustrates the actual situation. Appearance and disappearance of Castanea and Aesculus stands were related not only to climate, but also to the surrounding environment, i.e. sea level change at the Satohama site. Other factors also might influence hansaibai activities. When the distribution of Castanea and A. hansaibai activities are considered, one should be careful to consider the environment of the site. 5.4. Distribution of hansaibai of Castanea and Aesculus trees The sites where hansaibai of Castanea and Aesculus were observed were mapped in Fig. 14. The Tohoku region (the northern part of Honshu Island) and the Hokuriku region (Japan Sea Coast area in Central Japan) were the main
Fig. 14. Jomon archaeological sites with an evidence of Castanea and Aesculus hansaibai (Goto and Tsuji, 2001; Kiyonaga, 1990; Miyamoto et al., 1999; Tsuji, 1989).
distribution areas. In this study, no evidence of hansaibai in Western Japan was detected based on pollen analysis. It is possible that it spread at least to the Tohoku and Hokuriku regions during the Early to Middle Jomon Period (7000–3500 BP). Watamabe (1981) also argued that hansaibai developed in Eastern Japan from the Early Jomon Period to the Middle Jomon Period (7000–3500 BP) that corresponds to this result. Watamabe (1981) also mentioned that large longhouses, with large amounts of nuts preserved in the attic for winter food, were often found along the Japan Sea coastline (Fig. 15). Remains of raisedfloor houses were also found at the Sakuramach site, Toyama Prefecture (Sakuramachi-hakkutsu-chosadan, 2001). That kind of house was usually seen at sites from the Yayoi period for grain preservation because it is good for isolating grain from moisture and heat. It is also suitable for long-term preservation of nuts. It is necessary for people who are living in a snow-accumulation area to preserve a large amount of food for a long winter. In the hansaibai stage, storage structures should be ready for preserving this large amount of foods and a yearly plan of living must have been established. To harvest a large amount of nuts in autumn, hansaibai might have developed in this area. More than half of all sites and the earliest archaeological sites with hansaibai activity are located in the heavy snow area (Fig. 16). Snow accumulation might be a reason why hansaibai developed in the Tohoku and Hokuriku regions. Watamabe (1981) also suggested that the hansaibai developed in Western Japan during the Late Jomon Period (3500–3000 BP), but this discussion should be left until more pollen data are available. The earliest appearance of hansaibai seemed to be in the Hokuriku region and it appeared to spread in the Tohoku region. The Tohoku region, especially Aomori Prefecture
Fig. 15. Snow accumulation and archaeological sites where long house remains were found (Watamabe, 1981).
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seemed to be more active than other areas. The spread to the Kanto region was later than other areas. The earliest sites of agriculture in Japan can be seen in the Hokuriku and the Tohoku region. The grains of millet were found at the Tominosawa site from the Middle Jomon Period (4500–3500 BP) (Education Board of Aomori Prefecture, 1992) and the Kazahari site from the Late Jomon Period (3500–3000 BP) (Crawford, 1992) in Aomori Prefecture is one of the earliest sites of agriculture in Japan (Fig. 17). However, pollen of Fagopyrum was found from an even earlier period, e.g., the Early to Middle Jomon Period (7000–3500 BP) (Fig. 17). It was found at the Junichogata site, Toyama Prefecture from the Early Jomon Period
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(7000–4500 BP) (Yasuda, 1982) and at the Osawa site, Niigata Prefecture from the Middle Jomon Period (4500–3500 BP) (Maeyama, 1990). The cultural influence from the continent cannot be denied. However, the arrival of agriculture to Central Japan other than to the Hokuriku region came much later. The condition of both Western Japan and Eastern Japan is the same in terms of facing the Japan Sea, but agriculture developed in Eastern Japan first, introduced to the Hokuriku and Tohoku regions. Thus, hansaibai techniques and culture including preservation tools became the basis of accepting agriculture.
6. Conclusion
Fig. 16. Snow accumulation and sites where hansaibai activity was detected by pollen analysis.
Hansaibai culture developed due to the climate condition in the Jomon Period and this activity might have influenced the introduction of agriculture. The possibility of active and extensive hansaibai or cultivation of Castanea and Aesculus were detected by pollen analyses from Jomon sites mainly in the Hokuriku and Tohoku region. When Castanea hansaibai was practiced, the stands were made very close to the occupied area. However, regional differences in hansaibai activity might have existed. Most sites analysed exhibited the increase of Castanea and/or Aesculus pollen. The expansion of hansaibai culture in the Hokuriku and Tohoku region was indicated in this study although more data from pollen analyses from Jomon sites were necessary to reveal the expansion and distribution of hansaibai culture. The distribution of hansaibai or cultivation of Castanea and Aesculus is still under investigation. The periods of hansaibai were not continuous. The main factor is thought to be climate variations. Since the period of Jomon culture lasted almost 15,000 years, there were several warm periods and cold periods (see Sakaguchi, 1993; Fukusawa, 1998; Suzuki, 2000; Yasuda, 2002).
Fig. 17. The earliest sites of buckwheat and millet cultivation in Japan.
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Vegetation also changed dramatically (Yasuda, 1974a). Consequently, climate and vegetation must have influenced people’s food gathering activity since the Jomon people strongly depended on plant food (Watanabe, 1974). The results of pollen analyses on the Sannai-Maruyam site and the Kamegaoka site revealed an interesting relationship between temperature and periods of Castanea and Aesculus hansaibai. Castanea stands were made during warm periods and Aesculus stands were made during cold periods (Kitagawa and Yasuda, 2004). However at the Satohama site, where the annual average temperature is 1.2 1C higher than that in Aomori City, temperature drop did not have as much influence on Castanea hansaibai as in Aomori Prefecture. Even in the cold period of the early Middle Jomon Period (ca. 4500 BP), when the Castanea stand disappeared at the Sannai-Maruyama site, it was observed based on the pollen analysis from the Satohama site (Fig. 13). However, the colder climate during the later half of the Middle Jomon Period (ca. 4000–3500 BP) affected it and Aesculus hansaibai started. The average temperature might be related to the degree of influence on hansaibai and there might be little influence of climatic fluctuation in Western Japan. The responses to climatic fluctuation might depend on the temperature in each area. Hansaibai was also restricted by other factors, i.e. water availability and space. A period without a Castanea stand at the Satohama site was detected during a warm period although the stand seemed to grow just before the period. Sea level change may be the cause. Since the Satohama site is on a small island and is surrounded by the sea, the land is susceptible to sea level rise. Evidence that the occupied area was on the top of the hill during the warm period (in a booklet from Jomon Festa in Okumatsushima on October 5, 2002) might imply that the surrounding area might have been inundated during the Jomon sea transgression. There might have been no space to grow Castanea trees around the occupied area. Hansaibai of Castanea and Aesculus was practised by Jomon people using knowledge of plants. They selected kinds of plants for hansaibai and the way of consumption which might be suitable for their environment. It might not be easy to accept the idea of producing unknown food when agriculture was introduced to Japan because it was unpredictable how unfamiliar plants would yield every year for the first time. However, once exposed to the idea, they might easily have accepted it since they had already known how to plan to produce and store for consumption. Distribution of storage structure remains Watamabe, 1981; Sakuramachi-hakkutsu-chosadan, 2001) may indicate the development of a yearly plan for food storage. Storage structures were found mainly in heavy snow areas (Watamabe, 1981). In those areas, it was absolutely necessary that large amounts of food were stored for a long winter. To gain enough food, hansaibai might have started. The introduction of rice and millet agriculture occurred during the Middle to Late Jomon Period
(4500–3000 BP) and the earliest sites were found in the Tohoku region (Crawford, 1992; Education Board of Aomori Prefecture, 1992) and buckwheat introduction in the Hokuriku region was even earlier, during the Early to Middle Jomon Period (7000–3500 BP) (Yasuda, 1974b; Maeyama, 1990). It seemed that hansaibai was first introduced to the Hokuriku region, spread to the Tohoku region and became more active in the Tohoku region than in other areas. Surmising from this evidence, penetration of hansaibai culture encouraged introduction of agriculture and hansaibai and the cycle of nut production became a base for it. Acknowledgements The authors sincerely thank Mr. Hiroki Sugahara at the Historical Museum of Jomon Village Oku-Matsushima, Naruse Town, Miyagi Prefecture. We also thank Ms. Fujiko Suda at the Tohoku University for guiding sites in Tohoku region and suggestions while we were conducting the research. References Crawford, G.W., 1992. Prehistoric plant domestication in East Asia. In: Cowan, C.W., Watoson, P.J. (Eds.), The Origin of Agriculture, An International Perspective. Smithsonian Institute Press, Washington, p. 38. Education Board of Aomori Prefecture, (Ed.), 1992. Tominosawa (2) iseki Hakkuttu Chosa Hokokusho (Excavation Report of Tominosawa 2 Site). Education Board of Aomori Prefecture, Aomori (in Japanese). Education Board of Naruse Town, (Ed.), 1999. Satohama-kaizuka, Nrusecho Bunkazai Chosa Hokokusho, dai-5-shu (Satohama Shell Mound, Research Report of Cultural Treasure in Naruse Town, vol. 5, Education Board of Naruse Town, Naruse Town (in Japanese). Education Board of Oyabe City, (Ed.), 2000. Sakuramachi-iseki (Sakuramachi Site). Oyabe City and Tourism Association in Oyabe City (in Japanese). Fukusawa, H., 1998. Hyogaki iko no kikou no nennen hendo wo yomu (Yearly change of climate after last-glacial). Chikyu 68, 353–360 (in Japanese). Goto, K., Tsuji, S., 2001. Vegetation history since the Early Jomon period at Ooyazawa, Aomori, in the southern part of the Aomori Plain. Japanese Journal of Historic Botany 9, 43–53 (in Japanese with English abstract). Harlan, J.R., 1992. Crops & man, second ed. American Society of Agronomy, Crop Science Society of America, Madison. Hatakeyama, N., 2000. Middle Jomon Period. Bulletin of Aomori Prefectural Archaeological Artifacts Research Center 6, 21–24 (in Japanese). Hori, S., 1959. Kafun-bunseki no seika (results of pollen analysis). In: Shimizu, J. (Ed.), Kamegaoka; A Study of the Kamegaoka Neolithic Site, Aomori Prefecture, Japan. The Mita Historical Society, Keiogijuku University, Tokyo, pp. 147–148 (in Japanese with English summary). Japan Meteorological Agency: /http://www.data.kishou.go.jp/S. Jomon Eiga Seisaku-iinkai, 1996. Ichiman-nen Okoku, Aomori-ken no Jomon Bunka (10 Millenium Kingdom, Jomon Culture in Aomori Prefecture). Jomon Eiga Seisaku-iinkai (video tape in Japanese). Kitagawa, J., Yasuda, Y., 2004. The influence of climatic change on chestnut and horse chestnut preservation around Jomon sites in Northeast Japan with special reference to the Sannai-Maruyama and Kamegaoka sites. Quaternary International 123–125, 89–103.
ARTICLE IN PRESS J. Kitagawa, Y. Yasuda / Quaternary International 184 (2008) 41–55 Kitagawa, J., Nakagawa, T., Fujiki, T., Yamaguchi, K., Yasuda, Y., 2004. Human activity and climate change during the historical period in central upland Japan with reference to forest dynamics and the cultivation of Japanese horse chestnut (Aesculus turbinata). Vegetation History and Archaeobotany 13, 105–113. Kiyonaga, J., 1990. Pollen analysis of Holocene sediments from lowland along the Kashi river, southwestern part of Yokohama, Japan. Daiyonki Kenkyu (The Quaternary Research) 29, 351–360 (in Japanese with English abstract). Maeyama, S., 1990. Makimachi Osawa-seki niokeru Jomon-jidai Chuki Zenyo Shuraku no Shokubutu Riyo (Utilization of plants in Makimachi Osawa site from the early half of the Middle Jomon Period). Makimachi-shi Kenkyu (Study of Makimachi City) IV, 1–20 (in Japanese). Matsumoto, H., 1984. Geomorphological development of Higashimatsushima Bay, Miyagi Prefecture, Japan. Annals of the Tohoku Geographical Association 36, 46–53. Matsuyama, T., 1982. Konomi (Nuts). Hoseidaigaku-Shuppankyoku, Tokyo (in Japanese). Minaki, M., 1994. Enlargement of the fruit size of Castanea crenata Sieb, et Zucc, since the Jomon Period (since ca. 10,000 yBP) in Japan. Japanese Journal of Historical Botany 2, 3–10 (in Japanese with English abstract). Miyamoto, S., Yasuda, Y., Kitagawa, H., Takemura, K., 1999. Palaeoenvironmental changes in the Jakagamiike Moor, Fukui Prefecture, Central Japan, during the past 14,000 years. Japanese Journal of Palynology 45, 1–12. Moore, P.D., Webb, J.A., Collinson, M.E., 1991. Pollen Analysis. Blackwell Scientific Publication, Oxford. Nakamura, J., 1969. Kafunbunseki (Pollen Analysis). Kokonshoin, Tokyo (in Japanese). Nakao, S., 1976. Saibai-shokubutsu no Sekai (The World of Cultivated Plants). Chuokoronsha, Tokyo (in Japanese). Nishida, M., 1981. Man-plant relationships in the Jomon period and emergence of food production. Bulletin of the National Museum of Ethnology 6, 234–255 (in Japanese with English abstract). Nitobe, K., 1975. The geomorphic history of Lake Ogawara. Annals of the Tohoku Geographical Association 27, 25–35 (in Japanese with English abstract). Nitobe, T., 1973. Kafunbunseki ni tuite (Pollen analysis). In: Aomori (Ed.), Education Board of Aomori Prefecture, Kamegaika iseki Hakkutsuchosa Houkokusho, Kamegaoka Baipasu Kankei Maizobunkazai Hakkutsuchosa (Report on Archaeological Excavation of Kamegaoka Site, excavation before the construction of Kamegaoka bypass). Education Board of Aomori Prefecture, Aomori, pp. 166–170 (in Japanese). Odagawa, T., 2000. Incipient Jomon Period. Bulletin of Aomori Prefectural Archaeological Artifacts Research Center 6, 10–12 (in Japanese). Saitama Prefectural Museum (Ed.), 1982. Juno-Deitan-Iseki Hakkutsuchosa Hokokusho -Shizenibutsu-hen- (Research report of Juno archaeological site -natural remains-). Education Board of Saitama Prefecture, Urawa (in Japanese). Sakaguchi, Y., 1993. Kako 8000 nen no kikou-hennka to ningen no rekishi (climatic changes and human history of the past 8000 years). Journal of the Senshu University Research Society 51, 79–113 (in Japanese). Sakuramachi-hakkutsu-chosadan, (Ed.), 2001. Sakuramachi-iseki Chosagaiho (Excavation report from Sakuramachi site). Gakuseisha, Tokyo (in Japanese). Sasaki, Y., 1993. Ondashi-kukki (Ondashi Cookies). In: Shinpan Kodai no Nihon 1 (New edition, Ancient Japan 1). Kadokawa-shoten, Tokyo.
55
Sato, Y.-I., 2003. Evidence for Jomon plant cultivation based on DNA analysis of chestnut remains. Senri Ethnological Studies 63, 187–197. Shimakura, M., 1973. Palynomorph of Japanese Plants. Osaka Museum of Natural History, Osaka (in Japanese). Shiosawa, K., 1988. Kuri (Chestnuts). In: Aiga, T. (Ed.), The Grand Dictionary of Horticulture 2. Shogakukan, Tokyo, pp. 145–149 (in Japanese). Suzuki, H., 2000. Kikohenka to ningen–ichi-man-nen no rekishi-(Climate and humans-the history of 10,000 years-). Taimeido, Tokyo (in Japanese). Tsuji, S., 1989. Paleoenvironmental reconstruction in the dissected valley in Prehistory: Holocene paleoenvironment at the Akayama site in Kawaguchi, Central Kanto Plain, Japan. Daiyonki Kenkyu (The Quaternary Research) 27, 331–356 (in Japanese with English abstract). Tsutsumi, T., 2002. Origin of pottery and human strategies for adaptation during the termination of the Last-Glacial period in the Japanese Archipelago. In: Yasuda, Y., Shinde, V. (Eds.), Origins of Pottery and Agriculture. Lustra Press and Rolibook, New Delhi, pp. 241–262. Watamabe, M., 1981. Jomon-jidai niokeru bunatai bunnka (Beech forest culture during Jomon Period). Chiri (Geography) 26 (4), 39–46 (in Japanese). Watanabe, M., 1974. Various patterns of man’s adaptation to the natural environments in Jomon age. Daiyonki Kenkyu (The Quaternary Research) 13, 160–167 (in Japanese with English abstract). Yamamoto, T., Matsui, A., 1988. Dictionary of Japanese Archaeology. Nara National Cultural Properties Research Institute, Nara. Yamamoto, T., Sakai, A., 1977. Freezing resistance of chestnuts. Journal of Japan Forest Science 59, 360–367 (in Japanese with English abstract). Yasuda, Y., 1974a. Palynology and archaeology since the Late Glacial age in Japan. Daiyonki Kenkyu (The Quaternary Research) 13, 106–134 (in Japanese with English abstract). Yasuda, Y., 1974b. Kafunbunseki (Pollen Analysis). In: Education Board of Fukui Prefecture, (Ed.), Torihama-kaizuka (Torihama Shell Mound). Education Board of Fukui Prefecture, pp. 176–196 (in Japanese) Yasuda, Y., 1982. Kafunbunseki kara mita Toyama-wan engan no Jomon zennki no Iseki (Early Jomon sites around Toyama Bay seen from the aspect of pollen analysis). In: Education Board of Daimon Town, (Ed.), Koizumi-iseki (Koizumi site). Education Board of Daimon Town, Daimon-cho, pp. 99–108 (in Japanese). Yasuda, Y., 1989. Kafunbunseki ni tsuite (Pollen analysis). In: Education Board of Mie Prefecture, (Ed.), Uenoshi Ouchi, Kitaboriike-iseki hakkutsuchosagaiyo III (Excavation of Kitaboriike Archaeological site, Ouchi, Ueno City III). Education Board of Mie Prefecture, Ueno (in Japanese). Yasuda, Y., 1995. Kuribayashi ga sasaeta kodona bunnka (highly developed culture supported by chestnut stands). In: Umehara, T., Yasuda, Y. (Eds.), Jomon Bunmei no Hakken (Discovery of Jomon Civilization). PHP Kenkyusho, Tokyo, pp. 118–153 (in Japanese). Yasuda, Y., 2002. Kodai-bunmei no Kobo (Rise and fall of ancient civilizations). Gakushu-kenkyu-sha, Tokyo (in Japanese). Yokoi, M., 1989. Tochinoki-zoku (Genus Aesculus). In: Aiga, T. (Ed.), The Grand Dictionary of Horticulture 3. Shogakukan, Tokyo, pp. 390–393 (in Japanese). Yoshikawa, A., Yoshikawa, J., 2003. Satohama-kaizuka Nishihata-kitachiten ni okeru Jomon-jidai-zenki no shokubutsu-kaseki-gun (Plant fossil from Nishihata North point at Satohama shell mound during the early Jomon Period). In: Ancient Forest Research, (Ed.), Satohamakaizuka Nishihata-kita-chiten no shizenkagaku-bunseki (Natural scientific analysis on Nishihata North point at Satohama shell mound). Naruse Town, pp. 1–12 (in Japanese).