Mediterranean valleys revisited: Linking soil erosion, land use and climate variability in the Northern Levant

Geomorphology 101 (2008) 429–442

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Geomorphology j o u r n a l h o m e p a g e : w w w. e l s e v i e r. c o m / l o c a t e / g e o m o r p h

Mediterranean valleys revisited: Linking soil erosion, land use and climate variability in the Northern Levant Jesse Casana Department of Anthropology, University of Arkansas, Fayetteville, AR 72701, USA

A R T I C L E

I N F O

Article history: Received 1 September 2005 Accepted 1 April 2007 Available online 13 March 2008 Keywords: Soil erosion Orontes River Geoarchaeology Settlement history Turkey Alluvial fills

A B S T R A C T This paper presents results of geomorphological and archaeological investigations undertaken in several small drainage basins in the Jebel al-Aqra region of southern Turkey. By focusing intensive archaeological settlement survey in basins where securely dated sequences of sedimentary valley fills have been recorded, spatially and temporally linked, high-resolution records of land use and soil erosion have been generated. Sedimentary data show that throughout most of the Holocene, floodplains remained rather stable, allowing deep soils to form. But in the past two millennia, probably from AD 150–700, a phase of severe soil erosion was initiated and resulted in the deposition of 3.5–5.0 m of alluvial sediments on valley floors. Archaeological and historical evidence suggest that while these areas were occupied by agrarian communities since at least 2800 BC, nearly three millennia of cultivation during the Bronze and Iron Ages had relatively little effect on soil erosion. The intensification of settlement throughout the region and the conversion of upland areas to intensive agricultural production during the Hellenistic, Roman and late Roman periods (300 BC–AD 650), however, created the necessary preconditions for severe soil erosion to occur. These data are compared against modern and paleoclimate studies of the eastern Mediterranean, which show an extremely variable precipitation regime and the effects that it can have on erosion. A 400-year lag between the initial settlement of upland areas and the first evidence of soil erosion suggest that it may have been the intersection of extreme precipitation events with particular land use conditions of the Roman and late Roman periods which worked together to drive soil erosion. © 2008 Elsevier B.V. All rights reserved.

1. Introduction Geomorphologists and archaeologists have long suspected that landscapes of the Mediterranean and Near East have been significantly degraded since they were home to flourishing civilizations in antiquity, but the cause of this presumed change has been contentious from the beginning. Some authors, such as Huntington (1911), believed that this transformation was the consequence of a significant change in climate, while others, such as Reifenberg (1936), saw people as the destructive agents. Despite many advances in understanding the physical processes driving soil erosion, as well as climatic and regional settlement histories, these two basic perspectives regarding the causes of land degradation during the Holocene have continued to dominate geoarchaeological literature. Since Vita-Finzi's (1969) claim that the widespread uniformity in valley fill sequences across the Mediterranean was evidence that climate change had been responsible for their formation, it has often been argued that valley fill sequences are more complex than his simple, “Older and Younger Fill” model allows (e.g., Butzer, 1969; Wagstaff, 1981; van Andel et al., 1986). Therefore, land use, rather than climate, was seen as the main culprit driving ancient

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Mediterranean soil erosion. In reviews of this longstanding debate, Bintliff (2000, 2002) castigates researchers for focusing myopically on either culture or climate as the ultimate cause of erosion, arguing instead that the intersection of extreme climatic events and particular land use conditions creates a “window of opportunity” in which episodes of severe erosion occur. While the need for more integrated investigations into the causal mechanisms driving ancient soil erosion and the formation of valley fill sequences is now widely recognized (e.g., McGlade, 1999; Wilkinson, 1999; Rosen and Rosen, 2001; Wiseman, 2007), it remains unclear how to move from a conceptual understanding that erosion is a product of land use, precipitation, and other factors, to a practical application of this concept in structuring fieldwork and interpreting sedimentary and archaeological data. Butzer (2005) argues persuasively that to address an issue as complex as Holocene land degradation in regions like the Mediterranean and Near East, where humans have lived and farmed for 10,000 years or more, requires us to integrate systematically geomorphological, archaeological, and other scientific investigations. This project addresses this basic interpretive problem through coordinated geomorphological investigations and archaeological settlement surveys undertaken within three relatively small drainage basins in the northern Levant. Because of complex problems of sediment storage and transport, floodplain sedimentary sequences

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from larger river basins are extremely difficult to interpret, particularly with regard to the timing of hillslope erosion events versus the timing of downstream sediment deposition (Beach, 1994; Trimble, 1999; Walling, 2001). Because sedimentary sequences in valley fills found within very small basins are more direct products of changes in runoff and erosion on nearby slopes, they provide localized, long-term records of soil erosion at relatively high-temporal resolution and enable these records to be conclusively linked to local histories of land use (e.g., Knox, 1977, 2001). Projects in many parts of the world, including Meso-America (McAuliffe et al., 2001) and Crete (Krahtopoulou, 2001), have successfully reconstructed soil erosion histories by recording sedimentary sequences within small drainage basins, but the present study takes this basic principle a step further, by closely coordinating geomorphological investigations with intensive archaeological settlement surveys and historical analyses of ancient land use practices. These various lines of evidence are then compared against modern and paleoclimate data from the region, suggesting how changing land use might have interacted with climate variability to drive land degradation over time. Results of this study offer a better means of understanding the complex interactions among cultural and environmental processes in driving ancient soil erosion and the development of the Mediterranean and Near Eastern landscapes over the past several thousand years. 2. Regional setting This study was undertaken in an upland area to the south of the Amuq Plain (also known as the Plain of Antioch) in what is today southern Turkey. The Amuq has a long history of dense human settlement dating back at least to the Pottery Neolithic (c. 7000 BC;

Braidwood and Braidwood, 1960) and was home to several major archaeological excavations during the 1930s and 1940s, including those at the Bronze Age capital of Tell Atchana (ancient Alalakh; Woolley, 1955), the Seleucid and Roman city of Antioch (Elderkin [ed.], 1934), and the Oriental Institute's Syro-Hittite Expedition (Braidwood and Braidwood, 1960; Haines, 1971). This project was undertaken as part of the Oriental Institute's Amuq Valley Regional Project (AVRP), a broader effort to better understand the settlement and environmental histories of this important region through an interdisciplinary regional research program incorporating archaeological settlement survey, geomorphological and paleo-environmental analyses, and targeted excavations at key sites of various periods (Yener et al., 2000; Yener [ed.], 2005). Herein I focus on three small drainage basins within an upland region known as the Jebel al-Aqra, just to the east of Antakya (ancient Antioch). These basins include the Zengin Valley, measuring about 31 km2, the Avsuyu Valley measuring about 29 km2, and the small Ilica Valley, measuring 4.5 km2 (Fig. 1). The hills of the Jebel al-Aqra are composed primarily of highly erodable sandstones and marls of Tertiary age, with occasional outcrops of older limestones in the western edges of the hill region. Modern soils on hills within the study area are generally extremely shallow, measuring less than 50 cm in depth. In many areas, slopes have been eroded to plough-scarred bedrock (Fig. 2A), attesting to the presence of deeper soil cover in the past. Evidence exists that rates of erosion have been rapidly increasing over the past century, as seen in gullying, denuded badlands, and mass movement of slope materials. In some places, olive trees have been left on pedestals, indicating soil loss of up to 30 cm from individual fields over the past century. Evidence of ancient or early modern agricultural terracing is rare, except in the upper reaches of the larger two valleys. The region receives relatively abundant, although rather variable,

Fig. 1. Map of the Jebel al-Aqra region of southern Turkey, illustrating the three drainage basins investigated in this study. The highest peaks in this area rise to 500 masl while the Orontes River floodplain is at about 90 masl. Letters A–E indicate the locations of sedimentary sections illustrated in Fig. 3.

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Fig. 2. (A) Plough-scarred bedrock exposed on a hillside in the Jebel al-Aqra. (B) A section exposed in an incised stream bed in the Avsuyu Valley, illustrated in Fig. 3E. A Roman building, preserved as several courses of rounded stones, is exposed in the bottom of the section and is buried by 4.5 m of alluvial sediment (author for scale).

precipitation, with annual totals typically ranging from 500–1500 mm/ year. In this Mediterranean climate, more than 75% of total annual precipitation falls in the winter and early spring months, with little or no precipitation between May and September. Fed by rainfall and numerous springs, valley floors are verdant and agriculturally productive today and probably throughout the settled history of the region. Modern farmers cultivate a variety of crops, with valley floors dedicated to vegetables, cotton, tobacco, whereas upland areas are reserved for olive orchards and wheat where soils are present. 3. Valley fills and the history of soil erosion To document the history of soil erosion in the Jebel al-Aqra region, I recorded sedimentary exposures found in incised stream beds at the mouth of each drainage basin. The location of each section is indicated in Fig. 1. These three sedimentary sequences, described below, correspond closely to one another and provide a relatively detailed record of local soil erosion (for more detailed discussion of sedimentary data, see Casana, 2003a: Chapters 2 and 5). The Ilica Valley, which opens onto the Amuq Plain about 15 km northeast of Antakya, provides the most complete and securely dated sedimentary sequence of these three basins. It is composed predominantly of sandstones, with a small outcrop (c. 0.5 km2) of limestone exposed near the valley mouth. A stream that drains the valley flows on the north side of a mounded tell site (designated “AS 227” following the AVRP site numbering system; see Casana and Wilkinson, 2005) at the mouth of the valley, as it appears to have done

since the initial occupation of the site during the early third millennium BC. Today, the stream bed has incised deeply into the alluvial fan and floodplain sediments that have built up during the late Pleistocene and Holocene (Fig. 3: sections A–B). The deepest unit, below 6 m, is a hard, calcareous, light olivebrown paleosol, which is overlain by a cobble fan composed of poorly sorted and weakly bedded cobbles, interspersed by gravel beds, probably dated to the late Pleistocene (Fig. 3: A7–8). The fan represents a high-energy flow out of the Ilica Valley and contains abundant later Middle Paleolithic (50,000–20,000 BP) stone tools. Above the cobble bed, at c. 4 m depth, a dark grey layer of blocky alluvial silt is capped by a well-formed, dark humic paleosol, with abundant calcium carbonate concretions throughout the upper horizon (Fig. 3: A6). This second, later paleosol represents a stable floodplain surface. While the timing of the deposition of these sediments is unknown, the surface remained relatively stable into the Roman period, evidenced by the presence of a large masonry structure overlying it. The building is made of well-shaped limestone blocks, consistent with a Roman date, and sherds contained in overlying sediments suggest a pre-fifth century AD date for its initial construction. Overlying the building, another alluvial fan is composed of poorly sorted, moderate energy gravel and sand beds, pointing to a significant increase in the rate of erosion (Fig. 3: A5, B5). The rapid accumulation of this gravel fan in the late Roman period is suggested by the frequent inclusion of pottery fragments dating from the first through fourth centuries AD. Subsequently, another small stone wall was built on top of the gravel fan, about 20 m upstream. The structure

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Fig. 3. Diagram illustrating valley fill sedimentary sequences recorded in the Ilica, Zengin, and Avsuyu Valleys of the Jebel al-Aqra (see Appendix A).

provides an approximate date for the initial deposition of the fan, between the fourth and seventh centuries AD (Fig. 3: B4). Finally, the small wall and ground surface were covered by a dark grey-brown clay, the deposition of which was punctuated by occasional short periods of stability as evidenced by the formation of several weak Ahorizons (Fig. 3: A2–4, B2–4). These units contain abundant ceramic inclusions of consistent late Roman date. The lack of later cultural material within these units, despite the presence of a sizable medieval settlement at the nearby archaeological site, strongly suggested they were deposited during the fourth to seventh centuries AD. These units were finally capped by a shallow silty clay in which the modern soil has formed and which contains occasional ceramics of Middle Islamic date (tenth–fourteenth centuries AD; Fig. 3: A1, B1). In the Avsuyu Valley, a clearly exposed sedimentary sequence, which corresponds closely to that at Ilica, was found near the mouth of the basin where the modern streambed has been deeply incised into the valley fill sediments (Fig. 3: D; Appendix A). On the opposite side of the stream bank, a Roman building (AS 271) was discovered buried below 4 m depth, which provides an unambiguous post-Roman date for most of the sequence (Fig. 3: E). The building, constructed of roughly hewn sandstone and limestone blocks, cuts into a dark, humic paleosol of a hard, silty clay matrix (Fig. 3: D7, E7). The depth of soil formation and the presence of calcium carbonate nodules at 35–55 cm down the horizon indicate that this unit formed the ground surface of the valley floor during the several millennia prior to the Roman period and probably corresponds to the second paleosol found in the Ilica Valley (Fig. 3: A6). Several roof tiles are visible, collapsed on top of the stone building, sealing charcoal fragments and very distinctive ceramics, sherds of Eastern terra sigillata-A that are securely dated to the mid-second century AD. Subsequent to the abandonment of the building, a rapid aggradation of blocky brown to pale brown silt loam occurred. This immediately overlying flood deposit (Fig. 3: D6, E6) is noticeably darker and coarser, containing common sand grains, occasional pebbles and relatively common cultural materials, all of a Roman– late Roman date. The sediment characteristics suggest a higher energy

deposit than the finer-grained overlying strata, and the dark color indicates that it may have been the product of topsoil erosion within the valley. Several weak soil horizons, representing short-lived periods of stasis, are visible throughout the upper sequence, although no distinct paleosols are visible (Fig. 3: D2–5). Potsherds and tile fragments are common throughout these horizons, but decrease towards the top of the sequence. As in the Ilica section discussed above, cultural materials date consistently to the Roman to late Roman period (AD 200–700), indicating that the majority of the fill aggraded during that time. The uppermost stratum (Fig. 3: D1) consists of much sandier material than underlying silts and correlates with a late phase of erosion in the valley related to the expansion of Ottoman agriculture in recent centuries. Essentially the same sedimentary sequence can be traced for several hundred meters throughout the modern stream bed, indicating that the sequence preserved at AS 271 is representative of the entire valley fill sequence. In the Zengin Valley, the largest basin investigated, a similar sedimentary sequence was recorded in the side of the modern stream bed. It was located immediately adjacent to a relatively large settlement (AS 344) of Seleucid through Early Islamic date (300 BC– AD 800), 50 m downstream from an ancient stone-built bridge or dam (Fig. 3: C; Appendix A). The lowest unit of the sedimentary section (Fig. 3: C6) is a well-developed paleosol, composed of a dark brown, blocky clay loam with abundant calcium carbonate nodules and veins appearing about 25 cm from the top of the horizon. The approximate age of the soil and the period of floodplain stability it represents are indicated by its likely association with paleosols in other sedimentary sections discussed above, and by the presence of calcium carbonate nodules that probably required several thousand years to form (Goldberg, 1994; Goudie, 1995; Davies, 2005; Retallack, 2005). Radiocarbon dating of a freshwater gastropod shell, contained in the upper part of the horizon, yielded a date of 3630 ± 40 BP (calibrated to 2030–1930 BC at 1 sigma using OxCal), affirming that the soil is Bronze Age or younger. The soil, therefore, was likely contemporary with the pre-Roman paleosols recorded in the Ilica and Avsuyu Valleys. Unfortunately, radiocarbon analysis of gastropod shells contained in

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upper horizons (Fig. 3: C1 and 4) suffered from hard-water contamination, as is common in carbonate rich regions like the Jebel al-Aqra. It is possible that the one date reported here is also too old for the same reason. Recently developed techniques for correcting the measured 14C activity of gastropod shells may improve the reliability of such dates in the future (Pigati, 2002). Subsequently, a period of rapid aggradation of the valley floor ensued, probably the result of relatively high-energy floods that deposited a silt loam with high amounts of sand (Fig. 3: C5). While it is difficult to determine the precise date at which the aggradation occurred, it was followed by a short period of stability during which a weak soil developed on the surface of Unit 5 at about 260 cm below the modern surface. The uppermost part of this horizon contained abundant ceramics of the fourth to sixth centuries AD, which are likely related to the contemporary occupation at the nearby settlement (AS 344). A renewed phase of rapid aggradation of the valley floor followed, which buried the late Roman horizon by an additional 250 cm of sediments (Fig. 3: C2–4). Only very subtle variation in color and texture is visible in the blocky, pale brown clays, which I interpret as several brief phases of stability. All artifactual inclusions found in these upper horizons are of late Roman date, suggesting that the latest phases of aggradation occurred during the fourth through seventh centuries. These sections provide overlapping lines of evidence for the history of hillslope erosion within the Jebel al-Aqra. The earliest portion of the sequence occurs only in the Ilica section, where Pleistocene gravels, attested by Paleolithic tools, bury an earlier Pleistocene land surface. The subsequent phase of aggradation, which deposited a blocky silt loam in all three basins, is difficult to date. This episode was followed, however, by a period of long-lived stability on valley floors during which time deep soil profiles developed prior to the first century AD. These paleosols suggest that this initial phase of hillslope erosion occurred in the mid-Holocene or earlier. A radiocarbon determination from the Zengin sequence (albeit from a gastropod shell) supports a Bronze Age or earlier date. Subsequently, a major increase in erosion occurred that resulted in the deposition of a moderately high-energy, fine-medium gravel fan over the Ilica paleosol, and finer-grained sandy alluvial deposits in the Avsuyu and Zengin Valleys. This phase of erosion is securely dated by the presence of buried Roman buildings and ceramics in two sections. Erosion of slope soils continued in all three valleys over the late Roman period, and caused the deposition of an additional 2.5–3.5 m of silt loam, interspersed by several periods of short-lived stasis. Subsequently, perhaps during the early medieval period, hillslope erosion and deposition of sediments on valley floors slowed and a weak soil developed, although the timing of this event is difficult to ascertain. Finally, a renewed phase of aggradation in all three valleys resulted in the deposition of an additional 25–40 cm of sediment, perhaps during the Ottoman or late medieval period. The recent incision of the stream beds which exposed the sections may have resulted from widespread abandonment of the region during the later medieval and Ottoman periods. Abandonment of upland agriculture would have decreased soil erosion and sediment loads, thereby leading to an increase in stream incision, which has been documented at numerous sites throughout the Mediterranean region (e.g., Chester and James, 1999; González-Sampériz and Sopena-Vicién, 2002; Keesstra et al., 2005). 4. Settlement and land use histories To link these valley sequences with the uplands, I provide evidence of watershed settlement and land use histories as revealed through archaeological survey, undertaken as part of the AVRP from 1995–1999 and 2000–2002 in the Jebel al-Aqra region (Verstraete and Wilkinson, 2000; Casana, 2003b; Casana and Wilkinson, 2005; Casana, 2007). These data provide the most complete picture of land use histories in the three basins that are part of this study, and are, therefore, critical in fully understanding the history of erosion. Intensive pedestrian transects,

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covering approximately 30% of the area, recovered virtually no evidence of sedentary occupation prior to the Early Bronze Age (c. 2800 BC). It is, therefore, likely that the area was forested or reserved for pasture during that period. The first significant evidence of settlement dates to the early third millennium BC, and by the mid-third millennium, occupation existed at six tell sites, ranging from 1–6 ha in size (Fig. 4A). As is typical of Bronze and Iron Age settlements in the Amuq Valley and throughout the northern Levant, all these sites are situated on valley floors, adjacent to the largest areas of cultivable land (Wilkinson et al., 2003; Casana, 2007). Each of these tell sites has produced evidence of occupation during each major period between the early third and mid-first millennia BC (the Bronze and Iron Ages). It is not possible to demonstrate definitively, based on surface collections alone, that all these sites were contemporaneously and continuously occupied over this entire 2500-year period, but analysis of ceramics suggests that in at least some phases all six sites were settled. Furthermore, the relative ease with which tells are located in archaeological survey makes it quite likely that the AVRP has recorded all mounded sites. Some smaller early sites could be buried beneath later alluvium on valley floors, though all evidence of Bronze and Iron Age settlements from throughout the Amuq Valley is found at high, mounded tell sites rather than at small, topographically flat sites (Casana, 2003a; Casana and Wilkinson, 2005; Casana, 2007). Therefore, the distribution of these tells probably represents a maximal view of settlement at any time during the Bronze and Iron Ages. Beginning in the Hellenistic period (c. 300 BC), a large number of new settlements began to be established away from the long-lived tell sites of the Bronze and Iron Ages, spreading throughout valley floors and high into previously unoccupied hills (Fig. 4B). Unlike the high, mounded tell-based occupation of earlier periods, these new settlements were more dispersed in internal architectural organization and in distribution throughout the landscape, meaning that they are preserved today only as topographically flat scatters of sherds, collapsed building materials, and other artifacts. The number of settlements continued to grow rapidly in the Roman period (150 BC– 300 AD), reaching a peak in the late Roman period (AD 300–600) when 75 settlements have documented evidence of occupation (Fig. 7B). While Bronze and Iron Age sites are relatively easy to locate in the field as they form prominent landscape features, sites of later periods are rather ephemeral and it is, thus, only possible to locate them through intensive pedestrian transects. Because less than onethird of the region was covered by intensive survey, the settlement distribution map, Fig. 4B, likely shows only a fraction of the sites that were occupied during the late Roman period (Casana, 2003a,b; Casana and Wilkinson, 2005). By the Early Islamic period (AD 750–1000), as many as two thirds of the Roman–late Roman sites were abandoned, and this trend continued over the Middle and Late Islamic periods. In sum, evidence from archaeological survey shows that two distinctly different phases of settlement existed in the Jebel al-Aqra region: one nucleated, tell-based phase during the Bronze and Iron Ages (3000–500 BC), and another more dispersed and intensive phase in the Hellenistic through late Roman periods (300 BC–AD 700). During each of these periods, the region was likely characterized by equally different land use regimes which can be partially reconstructed on the basis of ancient historical texts and other evidence. For the Bronze and Iron Ages, considerable disagreement exists among specialists regarding the organization of agricultural land use. But most scholars agree that these ancient communities produced the majority of their own food supply, in part because of the relatively limited role that markets played in the agricultural economy and in part because of the complex set of rights and responsibilities surrounding access to and ownership of land (Schloen, 2001). It is, therefore, likely that each settlement was surrounded by agricultural land which residents maintained. Cuneiform texts, dating to the mid-second millennium BC, found at nearby Tell Atchana indicate that most of these communities had cereal fields, olive orchards, and vineyards, as well as smaller garden plots (Wiseman, 1953). Analysis of the spatial distribution of tell sites in

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Fig. 4. A) Mounded tell sites in the Jebel al-Aqra region, occupied nearly continuously throughout the Bronze and Iron Ages (2800–500 BC). B) Sites occupied during the Roman and late Roman periods (100 BC–AD 650).

the greater Amuq Valley and of field sizes recorded in the Alalakh texts also suggests the approximate area that these agricultural plots might have covered. Small settlements probably cultivated 100–250 ha, while larger settlements worked no more than 400 ha immediately surrounding a residential core (Casana, 2003a, pp 369–383). These data enable a hypothetical arrangement of field systems surrounding tell sites in the Jebel al-Aqra, in which valley bottoms are dedicated to cereals and gardens, while small areas of nearby uplands are reserved for orchards and vineyards. This reconstruction, while only one possibility, provides a probable picture of maximal agricultural land use at any point during the Bronze and Iron Ages (Fig. 5).

The remainder of the landscape in the Jebel al-Aqra would likely have served as pasture for flocks of sheep and goat, and may have been forested. Given the very high rates at which traditional Mediterranean communities deplete woodland resources (Clark, 1996; Margaris et al., 1996; Miller, 2004), much of the region may have been deforested by the second millennium BC or at least reduced to maquis type scrublands. We still lack direct paleobotanical evidence for the Amuq region, as cores from the former Lake of Antioch bed did not yield well-preserved pollen grains (Wilkinson, 2000). Evidence from the Ghab Basin in Syria, just 30 km to the south of the Jebel al-Aqra, suggests that deforestation of upland areas may have begun as early as

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Fig. 5. Reconstruction of agricultural land use around archaeological sites (black) that were occupied during the Bronze and Iron Ages (2800–500 BC). Hatched areas = cereal cultivation, stippled areas = vineyards and orchards. The remainder of the landscape was likely dedicated to pasture and/or forested.

the Neolithic (c. 7500 BC; Yasuda et al., 1999). Meadows (2005), however, argues that these cores have been incorrectly dated, and that initial deforestation probably occurred several millennia later. Analysis of paleoethnobotanical data from the nearby site of Tell Qarqur in Syria does show a substantial decrease in charcoal and an increasing reliance on dung fuel between the third and first millennia BC, possibly indicating a depletion of woodlands (Smith, 2005). In whatever ways that upland areas were utilized by local communities in the Bronze and Iron Ages, these practices did not have a significant impact on hillslope erosion. By the Roman and late Roman periods, the Jebel al-Aqra and indeed much of the Levant had witnessed a radical transformation in land use practices. The sheer quantity of sites that has been found and the locations of sites throughout all topographic and environmental zones make it relatively certain that most if not all of the Jebel al-Aqra was under intensive cultivation during these periods. These settlements likely included a wide range of functional types, such as agricultural estates occupied by tenants or slaves, smallholding villages, isolated villas and farmsteads, monasteries and so forth (Whittaker and Garnsey, 1997; Ward-Perkins, 2001; Grey, 2002). Furthermore, these communities were almost certainly engaged in the production of a wide variety of agricultural products, intended for local consumption and for sale at the markets in the sprawling metropolis of Antioch (modern Antakya), a city with 300,000 or more residents in the late Roman period. Agricultural products were also exported in massive quantities throughout the Mediterranean, as is unambiguously documented in the wide-ranging distribution of amphorae (containers for olive oil and wine) that originated in the region (Decker, 2001). Writing in the fourth century AD, the orator Libanius, a resident of

Antioch and a witness to the settlements documented in the Jebel alAqra, stressed the agricultural productivity of these upland areas: We have hills either in our own territory or around it; some bisect the plain, others with a broad sweep enclose the entrance and bar it in at the outer limits. Some of them differ in appearance from the level plains for they are raised aloft, yet they vie in fertility with the lands at their feet. Farmers work there, in land no less desirable, driving their ploughs to the summits. In short, whatever the level plain alone produces elsewhere, here is produced by the mountain districts also. (Libanius, Oration 11.22 [trans. Norman, 2000]) Throughout his writings, Libanius also mentions many of the products these farms produced including olive, vines, cereals, vegetables, and more, and his accounts are reinforced by the extensive writings of the Roman agronomists (White, 1970). Because these products could be sold in an agricultural marketplace undoubtedly helped to spur the continual expansion of intensive agriculture into previously uncultivated upland areas like the Jebel al-Aqra (Casana, 2007). In highland areas above the limits of olive cultivation around 500–700 m (Grove and Rackham, 2001), farmers could specialize in the production of nuts; in arid regions too dry to reliably support cereals and garden crops, they could raise livestock. Unlike during the Bronze and Iron Ages, a complex patchwork of small fields, dedicated to a wide variety of crops, probably covered the entire Jebel al-Aqra. Studies from elsewhere in the Levant, where the remains of field systems are actually preserved, demonstrate the existence of a highly dissected agricultural landscape surrounding Roman and late Roman sites, as at the site of Qarawat bene Hassan (Dar,

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1986: Fig. 130) and in the middle Orontes River Valley of Syria (Philip et al., 2005). A similar division of the landscape into many small plots can be seen in the field systems that surround the so-called “Dead Cities” of the limestone uplands in Syria, preserved as large stone clearance walls. Such field systems are clearly visible in a CORONA image of the Jebel Zahwiye, only 30 km southeast of the Jebel al-Aqra (Fig. 6). Jones (1974: Chapter 10) argues that in the late Roman period, 50% of the land at most farms was reserved for cereal production and the remainder was split between olive and vine, with only a small proportion dedicated to garden and other crops. Very similar figures have been suggested by Dar (1986, p.247) based on archaeological data at Qarawat bene Hassan, where 52% of fields were likely devoted to cereals, 25% to orchard, and 22% to vineyard. Indeed, this same general picture has been argued to have been the norm throughout the GrecoRoman Mediterranean world (Gallant, 1991). Experimental studies demonstrate that these different crop types would have had very different effects on soil erosion (Kosmas et al., 1997). The spatial distribution of these cultivation practices, however, was likely very dynamic, as individual land owners or managers could change land use practices on a year-to-year basis (Grey, 2002). These frequent changes in agricultural practices assess how land was used at any specific place and time problematic, but it seems undeniable that virtually the entirety of the Jebel al-Aqra was devoted to some form of agricultural production throughout most of the Roman and late Roman periods. While many aspects of land use in the Jebel al-Aqra remain unknown for the Bronze–Iron Age and the Roman–late Roman period, a striking difference between the two phases is clearly evident. During the earlier period, relatively small areas of the valley bottoms and

slopes surrounding settlements were probably farmed or devoted to orchard and vineyard, while the remaining areas were probably reserved for pasture. In sharp contrast, during the later period, settlements were established throughout the hill zone, and virtually the entire Jebel al-Aqra region was brought under intensive cultivation of olive, vine, cereals, and other crops in many small fields. While soil conservation measures, such as terracing, could have served to prevent widespread land degradation as intensive agriculture extended into uplands, archaeological survey found almost no evidence of Roman or late Roman terrace systems, unlike in many other parts of the northern Levant where they are frequently wellpreserved. It is likely that instead, hillslopes throughout the Jebel alAqra region were ploughed and cultivated without terracing, as they often are today. The transformation from the Bronze Age to the Roman period, therefore, may have had a significant impact on soil erosion, because many areas of steep slope were brought under plough, leaving them highly susceptible to erosion during intense rainstorms. 5. Climate variability The relatively detailed and spatially linked records of soil erosion and land use discussed above appear to offer a fairly one-sided narrative, of human impact on the landscape. Climate variability over the mid- to late Holocene, however, must also be considered in the analysis. Unfortunately, in the Levant no annual paleoclimate series extends back more than a millennium and no paleoclimate records are found within the immediate vicinity of the Jebel al-Aqra region. The only nearby paleoclimate data of relatively high-temporal resolution is that derived

Fig. 6. A CORONA satellite image (November 1968) showing late Roman field systems in western Syria, about 40 km southeast of the Jebel al-Aqra. Fields appear as small, rectilinear features throughout the center of the image, and are preserved today as 1–3 m tall stone clearance walls.

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from speleothem analysis of Soreq Cave in the southern Levant, about 500 km south of the Jebel al-Aqra (Bar-Matthews et al., 1998). Fig. 7 plots the history of soil erosion, land use, and precipitation on the same temporal axis. It summarizes a) the erosional history of the Jebel al-Aqra whereby the average depth of floodplain aggradation in all sedimentary sections is expressed in meters/1000 years, b) the history of land use whereby the number of archaeological sites per period suggests the intensity of land use, with special emphasis shown for upland settlement, and c) the paleoclimate series for Soreq Cave as a proxy for relative trends in precipitation. When these three datasets are compared, it appears that almost no correlation exists between Holocene climate variability and soil erosion, while the extension of upland settlement seems to mirror the increase in floodplain aggradation precisely. We could conclude, therefore, that climate change played little or no role in driving Roman and post-Roman land degradation in the region. On closer analysis, however, we can see that the initial phase of extreme soil erosion did not begin until after AD 150, and possibly as late as the fourth century AD, while the extension of upland settlement began in force by the third century BC. This time lag suggests that a period of 400–650 years occurred between the time

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when forested or pastured upland landscapes were brought under intensive cultivation and the initiation of severe soil erosion. Similarly, the peak phase of soil erosion during the late Roman period (fourth– seventh centuries AD) was not a slow and progressive process, but rather one that appears to have taken place in several extreme events, interspersed by longer periods of stasis when little or no floodplain aggradation took place. These disjunctures point to the role that precipitation variability may have played in driving soil erosion within the valleys of the Jebel al-Aqra, perhaps as has been documented in the Platte River basin of southwestern Wisconsin, where extreme erosion events took place only at the intersection between intensive farming of the late nineteenth and early twentieth centuries and periods of exceptionally high rainfall (Knox, 2001). Because paleoclimate data for the Levant are only available in 50-year averages, however, it is impossible to know if an apparent increase in precipitation is the result of short periods of exceptionally high precipitation or of multi-decadal scale changes that are relatively moderate. Studies of modern and recent historical climate data in southern Turkey and other parts of the eastern Mediterranean provide some insight regarding the local precipitation regime. While annual

Fig. 7. A diagram illustrating: (A) the average sedimentation rate (m/1000 years) recorded in three basins of the Jebel al-Aqra, (B) the number of sites occupied per period within the same region, differentiating between lowland sites in valley bottoms and sites on hillslopes or hill tops where the impact of agriculture was likely greater, and (C) a reconstruction of average annual precipitation during the late Holocene, derived from speleothem analysis at Soreq Cave in the southern Levant, illustrated at 18 °C and 20 °C (after Bar-Matthews et al., 1998).

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precipitation in the Jebel al-Aqra region is relatively abundant, it is highly variable as is the case throughout Mediterranean regions of southern Turkey (Türkeş, 1996; Kadıoğlu, 2000; Türkeş et al., 2002; Türkeş and Erlat, 2005). For example, data recorded from 1961–1990 at a climate monitoring station run by the Turkish State Meteorological Service on the westernmost edge of the Jebel al-Aqra in Antakya (available online through the NOAA's National Climatic Data Center), shows that annual precipitation ranges from 591 mm to 1692 mm. This can be compared to data over the same period from a station in Aleppo, Syria, just 100 km to the east, where annual precipitation ranges from only 143 mm to 500 mm. It has long been understood that the effect of precipitation on soil erosion is determined less by the annual totals cited above, and more by the timing and intensity of individual rainfall events (Wischmeier and Smith, 1958), calculated in erosion modeling studies as an erosion index which represents the kinetic energy and duration of precipitation events. Data compiled for much of Turkey in the 1950s and 1960s show that erosion indices, representing the erosive potential of rainfall, vary considerably across the Mediterranean littoral, with average values for the period from 1957–1969 ranging from 323.52 in Dörtyol, to 225.27 in Antakya (immediately adjacent to the study area), to only 29.38 in Gaziantep (Güçer, 1972, p.29). Clearly, more frequent years of high annual rainfall totals, with a greater frequency of high-energy precipitation events, could have devastating impacts on an intensively utilized agricultural landscape like that which existed in the Jebel alAqra during the Roman and late Roman periods. Unfortunately, as discussed above, we lack high-resolution precipitation data for these time periods. The only annual resolution precipitation reconstruction available in the region comes from dendrochronological studies conducted in southern Turkey, to the west of the Jebel al-Aqra (Touchan et al., 2003). These data cover 660 years, from 1339 to 1998, and demonstrate conclusively the existence of significant decadal or longer-term variations in spring precipitation, a likely indicator of annual precipitation trends. A long string of wet years, like those documented in the mid-fifteenth or early sixteenth century occurring in tandem with intensive upland agriculture, could easily have initiated severe soil erosion in the Jebel al-Aqra, as is suggested by modeling efforts in the Mediterranean basin (e.g., Mulligan, 1998; Martínez-Casasnovas et al., 2002). The effects of such high-intensity rainfall events would have been greatly exaggerated if they were to occur out of season, during times when fields were freshly ploughed or recently planted and lacking protective vegetative cover. While the paleoclimate smoking gun remains elusive, strong likelihood exists that climate events like those discussed above had a significant effect on land degradation in the Jebel al-Aqra. Studies of modern desertification in the Mediterranean suggest that widespread transformations in land use are currently driving pronounced changes in the timing and severity of rainfall because the precipitation regime across the region is so sensitive to changes in surface airmass moisture and temperature (Millán et al., 2005). The intensification of agricultural land use that took place across the Mediterranean region during the Roman and late Roman periods could easily have had a similar effect on the local climate. Recent efforts to model land–atmosphere interactions in driving climate change during the Holocene suggest the presence of a generally more humid phase between the fifth and ninth century AD, caused in part by land use changes related to the expansion of Roman and late Roman agriculture (Reale and Dirmeyer, 2000; Reale and Shukla, 2000). Bolle (2003) points out that these modeling efforts do not prove the existence of such as phase, but some supporting evidence for a late Roman humid episode has been found in the Palmyra basin, where sedimentary data point to wetter conditions subsequent to about 2000 BP (uncalibrated) (Besançon et al., 1997). If, as these data suggest, a period of higher humidity in the Mediterranean occurred during the Roman–late Roman period, it may have led to a significant increase in storminess in the region of Antakya, which in turn would have greatly exacerbated upland soil erosion.

6. Discussion and conclusions This study has sought to develop a methodology by which archaeological settlement data, historical information regarding ancient land use practices, and geomorphological data can be integrated to explore interrelationships. By recording valley fill sedimentary sequences within select, small drainage basins and then conducting intensive archaeological settlement surveys within the same basins, it is possible to generate spatially and temporally relatable records of settlement, land use and soil erosion. In each of the three basins that are part of this study, detailed erosional histories have been reconstructed, while textual and archaeological data have been used to suggest a general picture of land use during different historical time periods. These data are then compared against variability in precipitation as documented in modern and paleoclimate data to suggest how climate might have interacted with prevailing settlement and land use regimes to drive land degradation over time. The results of this study demonstrate several significant findings. Firstly, it appears that the conversion of early pre-settlement woodland to farms and pasture, as likely occurred sometime prior to the Bronze Age, had a negligible effect on soil erosion within the basins of the Jebel al-Aqra. It is possible that the deposition of the lowermost silt found in sedimentary sections was related to an early clearance of forest, but these units cannot be dated securely, and, therefore, could also be a product of an extreme climate event, such as the Younger Dryas. In any case, data suggest that despite nearly three millennia of sedentary agriculture, Bronze and Iron Age land uses had relatively little impact on soil erosion. These results contrast with other parts of the Near East where scholars have argued that human activities drove land degradation as early as the mid-third millennium BC (e.g., Rosen and Goldberg, 1995; Cordova, 2008-this issue). In this case, however, when the entirety of the three valleys that are part of this study were brought under mixed cultivation of olive, vine and cereals during the Roman and late Roman periods, severe soil erosion was triggered. In particular, the conversion of upland areas, which had long been forested or reserved for pasture, resulted in a devastating loss of soil. Yet, while settlement data show that the conversion of uplands to agriculture had begun by 300 BC, the initial phase of massive erosion and aggradation of valleys floors did not occur until several centuries later, after AD 150 at the earliest. This lag indicates that Roman and late Roman land use regimes created the necessary preconditions for soil erosion to occur, but that it was not until these conditions intersected with a period of unusually high precipitation that erosion actually took place. Moreover, climate changes during the Roman and late Roman periods may very well have been influenced by land use changes which were occurring across the entire Mediterranean basin. The subsequent phase of erosion, resulting in aggradation of between 3.5 and 5.0 m of alluvial silts on valley floors, was punctuated by several short-lived episodes of stability, indicated by weak soil formation throughout the upper part of the sequences. Because the majority of this phase of erosion occurred during the peak period of upland settlement, the variability seen in the sedimentary sequence, alternating between periods of stability and aggradation, is likely the product of inter-annual, decadal or longer-term variation in the frequency and severity of storms like those documented in dendrochronological precipitation data from the past seven centuries. Thus, each of the short-lived episodes of greater stability visible in sedimentary data may represent periods during which high-intensity storms were less frequent, while the phases of rapid aggradation may be the product of periods of greater storminess. The ultimate cessation of aggradation, while difficult to date, occurred sometime after the late Roman period and is, therefore, contemporary with the gradual abandonment of most settlements in the region. Certainly, these findings illustrate the potential for closely coordinated archaeological and geomorphological research to yield

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insights into human–environment relationships and highlight the complex interaction of climate and land use in driving soil erosion over millennial timescales. Yet, we cannot ignore the evidence indicating that the particular agricultural regime which flourished during the Roman and late Roman periods ultimately resulted in devastating land degradation. Integrated analyses from throughout the Mediterranean basin over the past two decades show unequivocally that human activities are a large part of the story of soil erosion in the region (e.g., van Andel et al., 1986; van der Leeuw, 1998; Marchetti, 2002; Cordova, 2008-this issue). Yet, these studies have never fully explained VitaFinzi's (1969) core empirical observation: a lot of soil erosion occurred in late Roman times. Lacking archaeological settlement data, he understandably favored a climatic origin of the ‘Younger Fill.’ But it is increasingly evident that the entirety of the Mediterranean world saw a remarkable intensification of agricultural production and a rapid transformation in settlement organization during the Roman period, from Western Europe (van der Leeuw, 1998; Picazo et al., 2000; van der Leeuw, 2003), to North Africa (Barker et al., 1996), to the Near East (Wilkinson, 2003, 128–150; Casana, 2007). Certainly, archaeological surveys from throughout the Orontes River Valley (e.g., Marfoe, 1979; Tate, 1992; Marfoe, 1997; Tate, 1997; Casana and Wilkinson, 2005; Philip et al., 2005; Pamir, 2005; Tchalenko, 1953–8) and the Levant more generally (e.g., Finkelstein and Lederman, 1997; Blanton, 2000; Kennedy, 2000; Schwartz et al., 2000) have found that during the Roman and late Roman periods the density of settlement rapidly increased and was coupled with an expansion into uplands, desert margins, and other previously unoccupied areas. Palynological studies from the Levant further support these findings, showing a contemporary, massive increase in the cultivation of olives and other upland crops (Baruch, 1990; Baruch and Bottema, 1999; Meadows, 2005). The severe erosion of upland soils, documented in the present study, undoubtedly would have impacted the productivity of upland farms, and, thus, threatened the sustainability of economic and agricultural systems throughout the entire region. Such a decline must be considered in broader attempts to explain the abandonment of settlements in the northern Levant and the decline of its once great cities after about AD 700 (cf., Foss, 1996). Furthermore, the extremely high rates of soil erosion documented herein would have affected long-term and unpredictable changes in the physical landscape by adding a huge influx of sediments into local river systems (Butzer, 2005). Geomorphological investigations in coastal regions of the northern Levant have found a rapid infilling of bays and estuaries dating to the post-Roman period (Beach and Luzzader-Beach, 2008-this issue). Similarly, studies of the Orontes

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River floodplain have found 3 m of alluvial sediments burying Roman land surfaces on the Amuq Plain (Wilkinson, 2000; Casana and Wilkinson, 2005), while just 10 km downstream, the excavators of the city of Antioch found Roman levels buried below more than 6 m of sediment (Elderkin, 1934). These processes are likely one of the primary factors contributing to the formation of the Lake of Antioch and the consequent inundation of the Amuq Plain, and probably the Ghab Basin in Syria, below marshland (Wilkinson, 1997, 1999; Wilkinson et al., 2001; Casana 2003a,b; Meadows 2005). Both areas, once fertile agricultural plains, became submerged below shallow lakes and extensive marshland in the post-Roman period, likely because of rapid changes in basin topography caused by floodplain aggradation on the Orontes River. Until they were mechanically drained in the 1950s and 1960s, permanent or seasonal marshes persisted in the basins such that when archaeologists and geomorphologists first began working in the region during the 1930s, these centers of dense ancient settlement were unproductive, malarial swamps (Weulersse, 1940), while Bronze and Iron Age cities formed islands rising from the surrounding waters (Braidwood, 1937). However climatic variability and land use practices intersected in driving ancient soil erosion in the northern Levant, the ultimate effects of widespread soil loss proved to be unpredictable, devastating to local agricultural regimes and ecological systems, and fundamentally transformative to the cultural and physical landscape for centuries. Acknowledgements The archaeological and geomorphological fieldwork presented herein was conducted as part of the University of Chicago Oriental Institute's Amuq Valley Regional Project (AVRP), under the auspices of the Directorate General of Monuments and Museums, Turkey, and the Director of the Antakya Archaeological Museum. Fieldwork was funded during the 2001–2002 seasons through grants from the National Geographic Society, the American Research Institute in Turkey, and the University of Chicago. This project formed a portion of my dissertation research, the completion of which would not have been possible without the support and guidance of Tony J. Wilkinson. I also wish to thank colleagues in the Department of Antiquities and at Mustafa Kemal University in Anatakya, Turkey as well as the many members of the AVRP who contributed to the project over the years, especially the dedicated project personnel from the 2001–2002 seasons: Merih Erek, Asa Eger, Andrea de Giorgi, Tasha Vordestrasse, Ali Witsel, and Özlem Doğan.

Appendix A The following tables provide additional descriptions of sedimentary sequences for the Zengin Valley (Fig. 3: C) and Avsuyu Valley (Fig. 3: D). The Ilica Valley section was originally recorded several years earlier and is published in Wilkinson (2000) and Casana and Wilkinson (2005). Zengin Valley (Fig. 3: C) Depth (m) 0–1.10

Color

2.5Y 7/3 dry 2.5Y 5/3 wet 1.10–1.40 2.5Y 6/3 dry 2.5Y 5/3 wet 1.40–2.00 2.5Y 6/3 dry 2.5Y 5/3 wet (1) 2.00–2.30 2.5Y 6/4 dry 2.5Y 5/3 wet 2.30–2.40 2.5Y 7/3 dry 2.5Y 5/3 wet 2.40–3.30 2.5Y 6/2 dry 2.5Y 4/3 wet 3.30–4.05 2.5Y 6/3 dry 2.5Y 5/3 wet 4.05–bottom 5Y 6/2 dry of exposure 2.5Y 4/3 Wet

Texture

Structure

Boundaries

Notes

Silt loam

Weak blocky

Distinct lower

Rare CaCO3 nodules; occasional gastropod shells

Silt loam

Weak sub-angular blocky

Distinct upper, diffuse lower Sandy silt loam Very weak blocky Diffuse upper and lower Silty clay loam Weak sub-angular blocky Diffuse upper and lower Silt loam Weak blocky Diffuse upper; distinct lower Silty clay loam Sub-angular blocky Distinct upper; diffuse lower Sandy silt loam Very weak structure Diffuse upper; distinct lower Silty clay loam Angular blocky structure; shiny ped faces Distinct upper

Very rare CaCO3 nodules; rare crushed shell fragments; occasional root voids Occasional brownish-orange mottles; common crushed shell fragments; occasional coarse sand and stones up to 0.5 cm Occasional crushed shell fragments

Occasional coarse sand inclusions; rare shell fragments Common small shell fragments; very common medium-coarse sand Well-developed CaCO3 nodules and vein-nodules begin at 25 cm down horizon to bottom of profile; occasional gastropod shells (2)

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Avsuyu Valley (Fig. 3: D) Depth (m)

Color

Texture

Structure

Boundaries

Notes

0–0.30

2.5Y 7/3 dry 2.5 Y 5/4 wet 2.5Y 6/4 dry 10YR 5/4 wet 2.5Y 6/3 dry 2.5Y 5/4 wet 2.5Y 6/3 dry 2.5Y 4/4 wet 2.5Y 6/2 dry 2.5Y 5/4 wet 2.5Y 7/3 dry 2.5Y 5/3 wet 2.5Y 6/4 dry 2.5Y 5/4 wet 2.5Y 6/4 dry 2.5Y 5/4 wet 2.5Y 6/4 dry 2.5Y 5/4 wet 2.5Y 5/4 dry 2.5Y 4/4 wet 10YR 4/2 wet

Silt loam

Very weak structure

Distinct lower

Ploughzone at top of unit

Sandy silt loam

Very weak structure

Silt loam

Very weak structure

Silty clay loam

Medium to coarse sub-angular blocky

Silty clay loam

Very weak sub-angular blocky

Silt loam

Very weak sub-angular blocky

Silt loam

Weak prismatic structure

Silt loam

Weak prismatic structure

Sandy silt loam

Weak blocky structure

Sandy silt loam

Weak blocky structure

Hard silty clay

Angular blocky structure; shiny ped faces

Distinct upper and lower Distinct upper and lower Distinct upper, diffuse lower Diffuse upper and lower Diffuse upper and lower Diffuse upper and lower Diffuse upper and lower Diffuse upper, distinct lower Distinct upper, diffuse lower Diffuse upper

0.30–0.45 0.45–1.20 1.20–1.85 1.85–2.00 2.00–2.15 2.15–2.75 2.75–2.98 2.98–3.15 3.15–4.45 4.45–bottom of exposure

Rare medium to coarse sand Rare fine roots and root voids; very rare rounded pebbles

Occasional fine-medium root voids Occasional fine root voids Color is slightly darker than overlying unit Occasional sub-rounded stones up to 1 cm; base of horizon stones up to 4 cm Rare veins of pale grey silt (3–4 mm); occasional CaCO3 concretions (3) Occasional grey veins; well-developed, distinct CaCO3 concretions at 35–55 cm (4)

Notes: (1) This unit is visibly lighter in color than the overlying unit, although approximately the same Munsell value. (2) Radiocarbon determination on gastropod shell from this unit yields date of 3630 +/− 40 BP. Soil becomes slightly lighter in color at the base of the profile. (3) This unit is noticeably more mixed and more poorly sorted than horizons above and contains eroded topsoil and relatively abundant cultural materials. Calcium carbonate nodules may be secondarily deposited. Sherds are predominantly red-brown brittle wares of late Roman date. (4) The base of the horizon, just visible above the modern streambed, becomes slightly lighter in color, signaling the beginning of a developed B-horizon. On the opposite bank from the section, a large stone-built building is constructed into the horizon. Sherds contained in building and from surrounding soil date to the second century AD. References Barker, G.W.W., Gilbertson, D.D., Jones, G., Mattingly, D., 1996. Farming the Desert: the UNESCO Libyan Valleys Archaeological Survey. UNESCO, Soc. for Libyan Studies, Paris. Baruch, U., 1990. Palynological evidence of human impact on the vegetation as recorded in Late Holocene lake sediments in Israel. In: Bottema, S., Entjes-Nieborg, G., van Zeist, W. (Eds.), Man's Role in the Shaping of the Eastern Mediterranean Landscape. A.A. Balkema, Rotterdam, pp. 283–294. Baruch, U., Bottema, S., 1999. A new pollen diagram from Lake Hula. In: Kawanabe, H., Coulter, G.W., Roosevelt, A.C. (Eds.), Ancient Lakes: Their Cultural and Biological Diversity. Kenboi Production, Belgium. Bar-Matthews, M., Ayalon, A., Kaufman, A., 1998. Middle to Late Holocene (6,500 yr. period) paleoclimate in the eastern Mediterranean region from stable isotopic composition of speleothems from Soreq Cave, Israel. In: Issar, A.S., Brown, N. (Eds.), Water, Environment and Society in Times of Climatic Change. Kluwer Academic Publishers, Netherlands, pp. 203–214. Beach, T., 1994. The fate of eroded soil: sediment sinks and sediment budgets of agrarian landscapes in southern Minnesota, 1851–1988. Annals of the Association of American Geographers 84, 5–28. Beach, T., Luzzadder-Beach, S., 2008. Geoarchaeology and aggradation around Kinet Höyük, an archaeological mound in the eastern Mediterranean, Turkey. Geomorphology 101, 416–428 (this issue). doi:10.1016/j.geomorph.2007.04.025. Besançon, J., Delgiovine, A., Fortugne, M., Lalou, C., Sanlaville, P., Vaudour, J., 1997. Mise en évidence et datation de phases humides du Pléistocene supérieur dans la région de Palmyre (Syrie). Paléorient 23 (1), 5–23. Bintliff, J., 2000. Landscape change in classical Greece: a review. In: Vermeulen, F., de Dapper, M. (Eds.), Geoarchaeology of the Landscapes of Classical Antiquity. Stichting BABESCH, Leiden, pp. 49–70. Bintliff, J., 2002. Time, process and catastrophism in the study of Mediterranean alluvial history: a review. World Archaeology 33 (3), 417–435. Blanton, R.E., 2000. Hellenistic, Roman and Byzantine Settlement Patterns of the Coast Lands of Western Rough Cilicia. BAR International Series, vol. 879. Archaeopress, Oxford. Bolle, H.J., 2003. Climate, climate variability and impacts in the Mediterranean area: an overview. In: Bolle, H.J. (Ed.), Mediterranean Climate: Variability and Trends. Springer, New York, pp. 5–86. Braidwood, R.J., 1937. Mounds in the plain of Antioch: an archaeological survey. Oriental Institute Publication 48. University of Chicago Press, Chicago. Braidwood, R.J., Braidwood, L., 1960. Excavations in the plain of Antioch I: the earlier assemblages, phases A–J. Oriental Institute Publication, vol. 61. Oriental Institute Press. Butzer, K., 1969. Changes in the land. Science 165, 52–53.

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