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The effect of soil management on the soil faunal makeup of a cropped andosol in Central Japan
Soil & Tillage Research. 12 (1988) 177-186 Elsevier Science Publishers B.V.. Amsterdam - - Printed in The Netherlands
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T h e E f f e c t of Soil M a n a g e m e n t on the Soil F a u n a l M a k e u p of a C r o p p e d A n d o s o l in C e n t r a l J a p a n Y. NAKAMURA National Institute of Agro-Ent'ironnwntaI Sciences, T,.'~d~ba. ,3o.~. lbaraki ~d.t~.~7
(Accepted for publication 2 November 198T I
ABSTRACT Nakamura, Y.. 1988. The effect of soil management on the soil faunal makeup ~ta cropped andosol m central Japan. Soil Tillage Res.. 12: 1TT-186. The effects of fl)ur contrasting soil-management practices on soil fauna in an andl}s~l cropped to upland rice and winter wheat, were examined after a :~-year period. The treatments were as fldlows: direct drilling with organic mulch and without fertilizer: direct drilling without mulch and fertilizer: rotary digging without mulch and with fertilizer: direct drilling without muk'h and with fertilizer. The density of 5 animal groups, namely Enchytraeidae. Oribatei. Acari except Oribatei. Collembola and macro-animals, was significantly lower in the direct drilling without muk'h and the rotary digging, compared to the other treatments. In comparisml with rotary digging, direct drilling with fertilizer, increased soil hardness and enchytraeids and macro-animal densities, but decreased the yield of upland rice. The organic mulch of decomposed plant materials increased the density of all 5 animal groups. The organic mulch also increased soil pH. water content and ignition loss of soil, and decreased soil hardness. INTRODUCTION E a r t h w o r m s a n d o t h e r soil f a t m a are k n o w n to affect soil p h y s i c a l , c h e m i c a l a n d hiological p r o p e r t i e s , a n d c r o p p r o d u c t i v i o I S a t c h e l l , 1960: W a l l w o r k , 1976: Bal, 1982). I n J a p a n , h o w e v e r , e a r t h w o r m s h a v e d i s a p p e a r e d f r o m t h e m a j o r i t y o f soils u s e d for c r o p p r o d u c t i o n . T h i s is c o n s i d e r e d to he r e l a t e d to t h e h i g h r a t e o f p e s t i c i d e a p p l i c a t i o n a n d c o n t i n u o u s a r a b l e c r o p p i n g wit hout m a n u r e s , h o w e v e r , little r e s e a r c h has b e e n c o n d u c t e d in t his a r e a ( K i t a z a w a , 1981: N a k a m u r a a n d H a k o i s h i . 1 9 8 1 i . R e c e n t l y , F u j i k a w a (1976) r e p o r t e d t h a t h i g h p o p u l a t i o n d e n s i t y a n d c o m p l i c a t e d m a k e u p of o r i h a t i d m i t e s o c c u r in t h e c r o p field, u n d e r a s o - c a l l e d n a t u r e or ecological f a r m i n g , w h i c h was o n e c r o p p i n g s y s t e m a p p l i e d in J a p a n . T h i s does not allow I he use of a n y c h e m i c a l s . I n s t e a d m a n u r e h e a p s are u s e d as fertilizers. T h i s r e p o r t deals w i t h t h e soil, c r o p a n d soil f a u n a r e s p o n s e s a f t e r 3 y e a r s to d i f f e r e n t s o i l - m a n a g e m e n t p r a c t ices for u p l a n d rice in c e n t ral ,Japan. As to t h e soil f a u n a , t h e r e s u l t s of t h e first 2 y e a r s h a v e h e e n o u t l i n e d p r e v i o u s l y ( N a k a m u r a , 1988).
0167-1987/88/$03.50
(¢:~1988 Elsevier Science Publisher~; B.V.
178 MATERIALS AND METHODS
Experimental design and treatments The experiment was conducted on a cultivated andosol within the campus of the National Institute of Agro-Environmental Sciences of Yatabe-cho ( 3 6 : 0 1 ' N , 140°01'E) in central Japan. The soil had been under cereal cultivation by rotary digging without mulch and with commercial fertilizer for the 4 years prior to the application of the soil-management treatments. The top soil is a clay loam, overlying heavy clay horizons. The soil in the plough layer (0-20 cm) had 4.1 +0.8% organic matter content and a p H of 6.1 +0.9 at the beginning of this treatment. The experimental plots were 13 × 11 m except for Treatment 2 which was 13 × 5.5 m, replicated twice. The treatments were: (1) direct drilling with organic mulch and without fertilizer; (2) direct drilling without mulch and fertilizer; (3) rotary digging without mulch and with fertilizer; (4) direct drilling without mulch and with fertilizer. T r e a t m e n t 3 is the conventional cropping system in Japan. In this system, winter wheat (Triticum aestivum L. ) is not ready for harvesting before the April tillage operation necessary for the next summer crop, upland rice, Oryza sativa L. Just before the April tillage operation, winter wheat in the heading stage was cut and brought out from the plot. Except for T r e a t m e n t 3, upland rice was sown in the ridge (the spacing of the ridges is 55 cm in all 4 treatments) between the rows of wheat. Fertilizers were applied in a band along the ridge. During the growing season for upland rice in Treatments 3 and 4, 1 kg h a - I Simazine ( herbicide, CTHI~C1N.~), 5.5 kg h a - 1 DCPA ( herbicide, CgHgC12NO) and 4 kg ha ~M E P ( insecticide, CgH~NO.~PS) were applied. The soil surface of Treatment 1 was mulched yearly with 8.0 t ha-1 of decomposed plant material (mainly leaves of Quercus trees) in addition to the cover of the chopped dry plant materials (mainly leaves of Miscanthus sinensis Anderss.). The management of these plots is summarized in Table I.
Soil animal measurements Each plot was divided into square (1 × 1 m) blocks, from which one for enchytraeid worms and micro-arthropods (mites and Collembola) and two for macro-animals (earthworms and macro-arthropods) were selected, at random at each sampling time. To collect soil macro-animals, hand-sorting was done in a quadrat (50 × 50 cm in area and 40 cm in depth) at each block, between the ridges of upland rice. Soil sampling for enchytraeids and micro-arthropods was as follows. In each block, one sampling plot, consisting of four continuous quadrats arranged in a square, was laid out near the ridge of upland rice, a quadrat being 5 × 4 cm in area and 20 cm in depth. A soil sample was taken
179 TABLE I Management schedule for the experimental plots from April to October 1986 Month
April May
June
July Aug. Sept. Oct.
Management
TreatmenF
Cutting of winter wheat Rotary digging (depth 20 cm) Fertilization 0.8 t ha 1 of 8-8-8 commercial fertilizer Sowing of upland rice Harvest ( winter wheat) Weeding by hoeing Herbicide (DCPA) application Enchytraeids and micro-arthropods sampling Mulching Herbicide (Simazine) application Weeding by hoeing Fertilization 0.6 t ha 1 of 8-8-8 commercial fertilizer Insecticide ( M E P ) application Weeding by hoeing Weeding by hoeing Enchytraeids and micro-arthropods sampling Weeding by hoeing Enchytraeids and micro-arthropods sampling Crop and soil measurements Harvest (upland rice ) Macro-animal sampling Rotary digging (depth 20 cm ) Fertilization 1.0 t ha ~ of 6-9-6 commercial fertilizer Sowing of winter wheat
1
2
3
4
-
-
+ +
-
+ + + + + +
+ + + + +
+ + + + + + +
+ + + + + + + +
+ + + + + + + + -
+ + + + + + + + -
+ + + + + + + + + + +
+ + + + + + + + + + -
+
+
+ +
+ +
"+ = Management practices carried out: - = no management practices.
from each quadrat
using a rectangular
metal sampler
(5 × 4 cm in area and
5 cm in depth). Enchytraeid worms were collected by a modified O'Connor funnel (Nakamura and Tanaka, 1979 ) and micro-arthropods by a modified Tullgren funnel (Fujikawa, 1970). Soil samples for enchytraeids and miero-arthropods were o b t a i n e d a t 45 ( i n t h e t i l l i n g s t a g e ) , 105 ( i n t h e h e a d i n g s t a g e ) a n d 165 ( i n t h e r i p e n i n g s t a g e , 10 d a y s b e f o r e h a r v e s t i n g ) days after sowing, while soil quadrats for macro-animals were taken after the harvest of upland rice in October. The similarities between the macro-animal communities were calculated usi n g M o r i s i t a ' s ( 1 9 6 0 ) C). i n d e x . A v a l u e o f 1.0 i n d i c a t e s h i g h e s t s i m i l a r i t i e s .
180 Soil and crop measurements
Soil hardness was measured at 5-cm depth intervals down to 20 cm using a "Yamanaka" hand penetrometer (Yamanaka and Matuo, 1962). Soil water content (w/w) was measured by oven-drying (105~C for 48 h) samples. Soil pH was determined using a 1:1 soil to water ratio. Ignition loss, as an estimate of soil organic matter, was determined after heating the soil at 750 ° C for 5 h. Soil samples for these measurements were taken at 5-cm depth increments between the holes left by the soil hardness meter in the 4 blocks selected at random. These soil measurements were carried out on the day before harvesting the upland rice in October. The length, top and root weight of the upland rice were measured in the 10 blocks selected at random, 165 days after sowing. RESULTS Soil
Soil properties after 3 years under 4 soil management practices are shown in Fig. 1. Among the 4 treatments, T r e a t m e n t 3 (rotary cultivation) had the lowest values for the soil properties except ignition loss. Under direct drilling, soil hardness was highest in T r e a t m e n t 4 (fertilizer alone), intermediate in T r e a t m e n t 2 (without fertilizer or mulch) and lowest in T r e a t m e n t 1 (with organic mulch ). Soil hardness in the three direct-drilling treatments increased rapidly to a depth of 20 cm. Soil water content was highest under direct drilling with organic mulch at four soil depths. The organic mulch increased the values of pH and especially ignition loss at the 0-5 cm soil depth, but there was no significant difference at the remaining depths. 0
Soil hardness(kg/crn 2) 4 8 12 16 .
.
.
.
.
pH 6
5
.
7
5 ..___
20.I L,
~,s.e. 30
Water content(°to,w/w) 40
5 :r~atment - - ~ - - " .
15
Ignition loss (%) 17 19
21
""
,ot: Fig. 1. Soil hardness, water content, pH and ignition loss after 3 years under four soil-management practices, October 1986. Values are mean ± s.e.
181
Crop responses
Plant length and top and root weight, 165 days after sowing are shown in Table II. All three crop measurements were significantly lower in the two unfertilized Treatments (1 and 2 ) t h a n the two fertilized Treatments ( 3 and 4 ). Treatment 2 showed the lowest values. There was no significant difference between the 2 fertilized treatments in 3 crop measurements, but the yield of upland rice under direct drilling ( T r e a t m e n t 4) was only 70% of the rotary cultivated T r e a t m e n t 3 ( Table II). T A B L E II Plant length, top weight and root weight 165 days after sowing (10 days befbre harvesting) and yield of upland rice. Values are mean + SE Treatment
Plant length (cm) Top weight ( d r y g m ~ofrow) Root weight ( d r y g m ~of row) Yield ( k g l 0 h a ~)
1
2
3
4
70.0+_5.0
40.0+_3.1
91.5+_3.5
87.5+3.5
602 +_32
192 _+91
828 +_91
724 +_81
248 +_35
98 +_23
622 +_122
613 +112
158 +25
15 +_3
338 +_38
236 +_48
30
Enchytraeidae • Treatmenl(1) 20
~1'0 O O~
o
(2)
~
(3)
Oribatei 10
Acari exceptOribatel 20
~s.e
(4)
i 5 ~
o
Fig.
~ 10
45 105 165 (.June)(Aug) (Oct)
2,
5
-~.----~ .-~-~ o 45 105 165 45 105 165 Age (in days) of uptand rice
10
~t~.!..._..~'
45 105 165
Soil meso-animals after 3 years under 4 soil management practices 1986.
182 T A B L E III Number of macro-animals per m :~in the soil profile (0-40 cm) after 3 years under four soil management systems, October 1986 Macro-animal taxa
Treatment 1
Eisenia foetida Dendrobaena octaedra Pheretima hilgendorfi Pheretima sp. Philomycidae Aranea Armadillidiidae Porcellionidae
Oligochaeta
Gastropoda Arachnida Crustacea Chilopoda Diplopoda Symphylla Insecta
2
2 18 2 1 1 4 7 2 24 4
Orthoptera Tridaetylidae Dermaptera Hemiptera Cydnidae Reduviidae Diptera Coleoptera Harpalidae Staphylinidae Scarabaeidae Elateridae Chrysomelidae Curculionidae Coccinellidae
3
1 11
2
2
1 1
8
3 6
2
13
1 7
24 1 23 17
153 (17.6)
2 4 14
1 1 3 7 28 5 6
4 3 2 1
1
2
3
0.91 0.40 0.61
0.51 0.48
0.66
4
1 5 28 14 15 18 2
1 1 34 (5.4)
64 (4.7)
Values of similarities ( C}. index) between two treatments, based on the date of Table III Treatment
2 27 1 2
3
T A B L E IV
Treat ment
7
1
1
Total (SE)
4
137 (2.6)
18:~ Soil animals The population densities of 4 animal groups after 3 years under the soilmanagement practices are shown in Fig. 2, the faunal makeup of the macroanimals is summarized in Table III. High densities of the 5 animal groups were found in Treatment 1, especially Acari (Oribatei and other Acari), which maintained a high density throughout the surveyed period. In contrast, a low density of animals was found in Treatments 2 and ~ throughout the surveyed period. There was no significant difference in enchytraeids and macro-animal numbers between Treatments 1 and 4. In addition, the faunal makeup of macro-animals in these 2 treatments was very similar (C5.=0.91, Table IV). DISCUSSION The present results of soil animals obtained in 1986 agree with those of the previous 2 years (Nakamura, 1988). The tilled Treatment 3, in comparison to the direct-drilling treatments, produced the best growth of upland rice. Many authors (Wilcke, 1962; Satchell, 19581 have noted an increase in earthworms as a result of increased production of crops following fertilization. However, there were no earthworms in Treatment 3. In addition, Acari, Collembola and Enchytraeidae were also reduced in numbers until the harvest. This disagrees with other reports on the comparison of the above soil animal populations under till and no-till practices ( Stinner and Crossley, 1980; Loring et al., 1981 ). They described an initial sharp decrease in population, followed by an increase towards the end of' the growing season. The reason for the difference between the present study and the other reports is uncertain. But the absence of earthworms and persistent low densities ofenchytraeids and micro-arthropods were also observed in the previous 4 years before and after the beginning of this experiment (Nakamura, 1988; Y. Nakamura, unpublished data, 1987 ). This is thought to be mainly owing to the impact of tillage and partly to the effect of pesticide application. Tillage (moudboard ploughing, harrowing, etc.) generally decreases the abundance of soil animals (Ghilarov, 1975; Stinner and Crossley, 1980). The direct detrimental effects of tillage are partly caused by abrasive damage to the animals and partly to trapping of animals in the soil when it is inverted and the existing system of cracks and pores is destroyed. The indirect effects of tillage, such as drying of the uppermost part of the soil or removal of litter from the soil surface, are probably also of importance (Wallwork, 1976; Gill, 1969; Andren and LagerlSf, 1980; Lal and De Vleeschauwer, 1982). As to the pesticide, simazine reduces the numbers of Acari and Collembola (Edwards, 1970). Furthermore, Popovici et al. (19777 reported that atrazine, which is chemically related to simazine, can lower the numbers of Acari, Collembola, Enchytraeidae. Prot~zoa and adult insect, l)op-
184
ulations for as long as 4 months after its application. In this study, simazine was applied less than 4 months before the last measurement. The comparison of direct drilling ( T r e a t m e n t 4) with rotary cultivation (Treatment 3 ), both of which received the same pesticide and fertilizer applications, showed that direct drilling caused more changes within specific soil animal populations than the pesticide application. For example, earthworms were present under direct drilling. Furthermore, enchytraeids and macro-animals were significantly larger in number. But yield of upland rice was only 70% in Treatment 3. This is thought to be mainly owing to the effect of highest soil hardness. In Treatment 2, without fertilizer and mulch, the soil was not tilled and applied with pesticide. But the density of the measured five soil animal groups was significantly lower. This may be associated with the ground surface of soil, which was bare and exposed to the sunlight throughout the surveyed period, because of the poor growth of upland rice. In Treatment 1, on the contrary, all five animal groups, especially Aeari and Collembola were significantly larger in number. This indicates that organic mulch is beneficial for soil animals (Edwards and Lofty, 1969; Andren and Lagerlbf, 1983 ). Furthermore, mulch decreased the value of soil hardness and increased soil pH, water content and ignition loss. However, plant length and top and root weight were fairly low under direct drilling, and the yield was only 47'; of the tilled T r e a t m e n t 3. This is probably due to the slow release of plant minerals from the mulch in comparison with the fertilizer. In addition, it also suggests that measured animal groups merely live in greater abundance in better soil without contributing to soil productivity. The populations of the five animal groups studied were, however, too small for a beneficial effect to be expected. The addition of suitable organic matter for mulch is also important, because the influences on earthworm ( Graft, 1970) and Acari and Collembola ( Berg and Pawluk, 1984 ) populations vary with the quality of mulch. ('ONCI,USION
As compared with tillage in an upland rice field of Japan, direct drilling without a mulch led to an increase in soil hardness and numbers of enchyl raeids and macro-animals, but decreased rice yields. Direct drilling with an organic mulch but no fertilizer was beneficial for soil animals, but considerably decreased the rice yield. Further investigations are required concerning the quantity and quality of mulch to determine the contribution of soil animals to soil productivity. ACKNOWLEDGEMENTS
l thank Mr. M. Moriya, Mr. Y. Iizumi and Mr. H. Yamaguehi for their technical assistance.
185 REFERENCES Andren, O. and Lagerlbf, J., 1980. The abundance of soil animals (Microarthropoda, Enchytraeidae, Nematoda) in a crop rotation dominated by ley and in a rotation with varied crops. In: D. Dindal (Editor), Soil Biology as Related to Land Use Practices. Proc. 7th. International Soil Zoology Colloquium. E.P.A., Washington, D.C., pp. 274-279. Andren, O. and Lagerltif, J., 1983. Soil fauna (microarthropods, enchytraeids, nematodes) in Swedish agricultural cropping systems. Acta Agric. Scand., 33: 33-52. Bal, L., 1982. Zoological ripening of soils. Agric. Res. Rep., 850: 1-365. Berg, N.W. and Pawluk, S., 1984. Soil mesofaunal studies under different vegetative regimes in north central Alberta. Can. J. Soil Sci., 64: 209-223. Edwards, C.A., 1970. Effects of herbicides on the soil fauna. Proc. 10th. Weed Control Conf., 1970, 3: 1052-1062. Edwards, C.A. and Lofty, J.R., 1969. The influence of agricultural practices on soil micro-arthropod populations. In: J.G. Sheals (Editor), The Soil Ecosystem. Pubis. Syst. Ass., pp. 237-248. Fujikawa, T., 1970. Notes on the efficiency of a modified Tullgren apparatus for extracting oribatid mites. Appl. Entomol. Zool., 5: 42-44. Fujikawa, T., 1976. Oribatid mites in the nature farming field and conventionalfield. Edaphologia, 15:1-11 (In Japanese). Ghilarov, M.S., 1975. General trends of changes in the soil animal population of arable land. In: J. Vanek (Editor), Progress in Soil Zoology. Proc. 5th. Int. Colloquium on Soil Zoology. Academia, Prague, pp. 31-39. Gill, R.W., 1969. Soil microarthropod abundance following old field manipulation. Ecology, 50: 805-816. Graff, O., 1970. Der Einfluss verschiedener Mulchmaterialien auf den N~ihrelementgehalt yon Regenwurmri3hren im Unterboden. Pedobiologia, 10: 305-319. Kitazawa, Y., 1981. Soil animals. Kankyo-Kagaku, B-74-R 12-4, (In Japanese). Lal, R. and De Vleeschauwer, D., 1982. Influence of tillage methods and fertilizer application on chemical properties of worm castings in a tropical soil. Soil Tillage Res., 2: 37-52. Loring, S.J,, Snider, R.J. and Robertson, L.S., 1981. The effects of three tillage practices on Collembola and Acarina populations. Pedobiologia, 22: 172-184. Morisita, M., 1960. Measuring of interspecific association and similarity between communities. Mem. Fac. Sci. Kyushu Univ., Ser. E., 3: 65-80. Nakamura, Y., 1988. Effects of soil animals on soil habitat modification in nature farming (without chemical fertilizer and pesticide). In: Proc. 9th. International Soil Zool. Colloquium. Moscow. (in press). Nakamura, Y. and Tanaka, S., 1979. Vertical distribution of' Enchytraeidae in various habitats. Edaphologia, 19:1-12 (In Japanese with English summary). Nakamura, Y. and Hakoishi, T., 1981. Crop system and abundance of soil animals on Ishigaki island of subtropical zone. Edaphologia, 24: 1-10 (In Japanese with English summary). Popovici, I., Stan, G., Stefan, V., Tomescu, R., Dumea, A., Tarta, A. and Dan, F., 1977. The influence of atrazine on soil fauna. Pedobiologia, 17:209 215. Satchell, J.E., 1958. Earthworm biology and soil fertility. Soils Fert., 21: 209-219. Satchell, J.E., 1960. Earthworms and soil fertility. New Sci., 7: 79-81. Stinner, B.R. and Crossley, D. A., 1980. Comparison of mineral element cycling under till and notill practiees: an experimental approach to agroecosystems analysis. In: D. Dindal (Editor), Soil Biology as Related to Land Use Practices. Proc. 7th. International Soil Zoology Colloquium. E.P.A., Washington, D.C., pp. 280-287. Wallwork, J.A., 1976. The Distribution and Diversity o[ Soil Fauna. Academic Press, London, 355 pp. Wilcke, S.A., 1962. Untersuchungen fiber die Einwirkung wm Stallmist und Mineraldtingungauf
186 den Besatz und die Leistungen der Regenwiirmer im Ackerboden. Monogr. Angew. Entomol. 18: 121-167. Yamanaka, K. and Matuo, K., 1962. Studies on soil compaction (1). Jap. J. Soil Sci. Plant Nutr. 33:343-347 (In Japanese).
t TT
T h e E f f e c t of Soil M a n a g e m e n t on the Soil F a u n a l M a k e u p of a C r o p p e d A n d o s o l in C e n t r a l J a p a n Y. NAKAMURA National Institute of Agro-Ent'ironnwntaI Sciences, T,.'~d~ba. ,3o.~. lbaraki ~d.t~.~7
(Accepted for publication 2 November 198T I
ABSTRACT Nakamura, Y.. 1988. The effect of soil management on the soil faunal makeup ~ta cropped andosol m central Japan. Soil Tillage Res.. 12: 1TT-186. The effects of fl)ur contrasting soil-management practices on soil fauna in an andl}s~l cropped to upland rice and winter wheat, were examined after a :~-year period. The treatments were as fldlows: direct drilling with organic mulch and without fertilizer: direct drilling without mulch and fertilizer: rotary digging without mulch and with fertilizer: direct drilling without muk'h and with fertilizer. The density of 5 animal groups, namely Enchytraeidae. Oribatei. Acari except Oribatei. Collembola and macro-animals, was significantly lower in the direct drilling without muk'h and the rotary digging, compared to the other treatments. In comparisml with rotary digging, direct drilling with fertilizer, increased soil hardness and enchytraeids and macro-animal densities, but decreased the yield of upland rice. The organic mulch of decomposed plant materials increased the density of all 5 animal groups. The organic mulch also increased soil pH. water content and ignition loss of soil, and decreased soil hardness. INTRODUCTION E a r t h w o r m s a n d o t h e r soil f a t m a are k n o w n to affect soil p h y s i c a l , c h e m i c a l a n d hiological p r o p e r t i e s , a n d c r o p p r o d u c t i v i o I S a t c h e l l , 1960: W a l l w o r k , 1976: Bal, 1982). I n J a p a n , h o w e v e r , e a r t h w o r m s h a v e d i s a p p e a r e d f r o m t h e m a j o r i t y o f soils u s e d for c r o p p r o d u c t i o n . T h i s is c o n s i d e r e d to he r e l a t e d to t h e h i g h r a t e o f p e s t i c i d e a p p l i c a t i o n a n d c o n t i n u o u s a r a b l e c r o p p i n g wit hout m a n u r e s , h o w e v e r , little r e s e a r c h has b e e n c o n d u c t e d in t his a r e a ( K i t a z a w a , 1981: N a k a m u r a a n d H a k o i s h i . 1 9 8 1 i . R e c e n t l y , F u j i k a w a (1976) r e p o r t e d t h a t h i g h p o p u l a t i o n d e n s i t y a n d c o m p l i c a t e d m a k e u p of o r i h a t i d m i t e s o c c u r in t h e c r o p field, u n d e r a s o - c a l l e d n a t u r e or ecological f a r m i n g , w h i c h was o n e c r o p p i n g s y s t e m a p p l i e d in J a p a n . T h i s does not allow I he use of a n y c h e m i c a l s . I n s t e a d m a n u r e h e a p s are u s e d as fertilizers. T h i s r e p o r t deals w i t h t h e soil, c r o p a n d soil f a u n a r e s p o n s e s a f t e r 3 y e a r s to d i f f e r e n t s o i l - m a n a g e m e n t p r a c t ices for u p l a n d rice in c e n t ral ,Japan. As to t h e soil f a u n a , t h e r e s u l t s of t h e first 2 y e a r s h a v e h e e n o u t l i n e d p r e v i o u s l y ( N a k a m u r a , 1988).
0167-1987/88/$03.50
(¢:~1988 Elsevier Science Publisher~; B.V.
178 MATERIALS AND METHODS
Experimental design and treatments The experiment was conducted on a cultivated andosol within the campus of the National Institute of Agro-Environmental Sciences of Yatabe-cho ( 3 6 : 0 1 ' N , 140°01'E) in central Japan. The soil had been under cereal cultivation by rotary digging without mulch and with commercial fertilizer for the 4 years prior to the application of the soil-management treatments. The top soil is a clay loam, overlying heavy clay horizons. The soil in the plough layer (0-20 cm) had 4.1 +0.8% organic matter content and a p H of 6.1 +0.9 at the beginning of this treatment. The experimental plots were 13 × 11 m except for Treatment 2 which was 13 × 5.5 m, replicated twice. The treatments were: (1) direct drilling with organic mulch and without fertilizer; (2) direct drilling without mulch and fertilizer; (3) rotary digging without mulch and with fertilizer; (4) direct drilling without mulch and with fertilizer. T r e a t m e n t 3 is the conventional cropping system in Japan. In this system, winter wheat (Triticum aestivum L. ) is not ready for harvesting before the April tillage operation necessary for the next summer crop, upland rice, Oryza sativa L. Just before the April tillage operation, winter wheat in the heading stage was cut and brought out from the plot. Except for T r e a t m e n t 3, upland rice was sown in the ridge (the spacing of the ridges is 55 cm in all 4 treatments) between the rows of wheat. Fertilizers were applied in a band along the ridge. During the growing season for upland rice in Treatments 3 and 4, 1 kg h a - I Simazine ( herbicide, CTHI~C1N.~), 5.5 kg h a - 1 DCPA ( herbicide, CgHgC12NO) and 4 kg ha ~M E P ( insecticide, CgH~NO.~PS) were applied. The soil surface of Treatment 1 was mulched yearly with 8.0 t ha-1 of decomposed plant material (mainly leaves of Quercus trees) in addition to the cover of the chopped dry plant materials (mainly leaves of Miscanthus sinensis Anderss.). The management of these plots is summarized in Table I.
Soil animal measurements Each plot was divided into square (1 × 1 m) blocks, from which one for enchytraeid worms and micro-arthropods (mites and Collembola) and two for macro-animals (earthworms and macro-arthropods) were selected, at random at each sampling time. To collect soil macro-animals, hand-sorting was done in a quadrat (50 × 50 cm in area and 40 cm in depth) at each block, between the ridges of upland rice. Soil sampling for enchytraeids and micro-arthropods was as follows. In each block, one sampling plot, consisting of four continuous quadrats arranged in a square, was laid out near the ridge of upland rice, a quadrat being 5 × 4 cm in area and 20 cm in depth. A soil sample was taken
179 TABLE I Management schedule for the experimental plots from April to October 1986 Month
April May
June
July Aug. Sept. Oct.
Management
TreatmenF
Cutting of winter wheat Rotary digging (depth 20 cm) Fertilization 0.8 t ha 1 of 8-8-8 commercial fertilizer Sowing of upland rice Harvest ( winter wheat) Weeding by hoeing Herbicide (DCPA) application Enchytraeids and micro-arthropods sampling Mulching Herbicide (Simazine) application Weeding by hoeing Fertilization 0.6 t ha 1 of 8-8-8 commercial fertilizer Insecticide ( M E P ) application Weeding by hoeing Weeding by hoeing Enchytraeids and micro-arthropods sampling Weeding by hoeing Enchytraeids and micro-arthropods sampling Crop and soil measurements Harvest (upland rice ) Macro-animal sampling Rotary digging (depth 20 cm ) Fertilization 1.0 t ha ~ of 6-9-6 commercial fertilizer Sowing of winter wheat
1
2
3
4
-
-
+ +
-
+ + + + + +
+ + + + +
+ + + + + + +
+ + + + + + + +
+ + + + + + + + -
+ + + + + + + + -
+ + + + + + + + + + +
+ + + + + + + + + + -
+
+
+ +
+ +
"+ = Management practices carried out: - = no management practices.
from each quadrat
using a rectangular
metal sampler
(5 × 4 cm in area and
5 cm in depth). Enchytraeid worms were collected by a modified O'Connor funnel (Nakamura and Tanaka, 1979 ) and micro-arthropods by a modified Tullgren funnel (Fujikawa, 1970). Soil samples for enchytraeids and miero-arthropods were o b t a i n e d a t 45 ( i n t h e t i l l i n g s t a g e ) , 105 ( i n t h e h e a d i n g s t a g e ) a n d 165 ( i n t h e r i p e n i n g s t a g e , 10 d a y s b e f o r e h a r v e s t i n g ) days after sowing, while soil quadrats for macro-animals were taken after the harvest of upland rice in October. The similarities between the macro-animal communities were calculated usi n g M o r i s i t a ' s ( 1 9 6 0 ) C). i n d e x . A v a l u e o f 1.0 i n d i c a t e s h i g h e s t s i m i l a r i t i e s .
180 Soil and crop measurements
Soil hardness was measured at 5-cm depth intervals down to 20 cm using a "Yamanaka" hand penetrometer (Yamanaka and Matuo, 1962). Soil water content (w/w) was measured by oven-drying (105~C for 48 h) samples. Soil pH was determined using a 1:1 soil to water ratio. Ignition loss, as an estimate of soil organic matter, was determined after heating the soil at 750 ° C for 5 h. Soil samples for these measurements were taken at 5-cm depth increments between the holes left by the soil hardness meter in the 4 blocks selected at random. These soil measurements were carried out on the day before harvesting the upland rice in October. The length, top and root weight of the upland rice were measured in the 10 blocks selected at random, 165 days after sowing. RESULTS Soil
Soil properties after 3 years under 4 soil management practices are shown in Fig. 1. Among the 4 treatments, T r e a t m e n t 3 (rotary cultivation) had the lowest values for the soil properties except ignition loss. Under direct drilling, soil hardness was highest in T r e a t m e n t 4 (fertilizer alone), intermediate in T r e a t m e n t 2 (without fertilizer or mulch) and lowest in T r e a t m e n t 1 (with organic mulch ). Soil hardness in the three direct-drilling treatments increased rapidly to a depth of 20 cm. Soil water content was highest under direct drilling with organic mulch at four soil depths. The organic mulch increased the values of pH and especially ignition loss at the 0-5 cm soil depth, but there was no significant difference at the remaining depths. 0
Soil hardness(kg/crn 2) 4 8 12 16 .
.
.
.
.
pH 6
5
.
7
5 ..___
20.I L,
~,s.e. 30
Water content(°to,w/w) 40
5 :r~atment - - ~ - - " .
15
Ignition loss (%) 17 19
21
""
,ot: Fig. 1. Soil hardness, water content, pH and ignition loss after 3 years under four soil-management practices, October 1986. Values are mean ± s.e.
181
Crop responses
Plant length and top and root weight, 165 days after sowing are shown in Table II. All three crop measurements were significantly lower in the two unfertilized Treatments (1 and 2 ) t h a n the two fertilized Treatments ( 3 and 4 ). Treatment 2 showed the lowest values. There was no significant difference between the 2 fertilized treatments in 3 crop measurements, but the yield of upland rice under direct drilling ( T r e a t m e n t 4) was only 70% of the rotary cultivated T r e a t m e n t 3 ( Table II). T A B L E II Plant length, top weight and root weight 165 days after sowing (10 days befbre harvesting) and yield of upland rice. Values are mean + SE Treatment
Plant length (cm) Top weight ( d r y g m ~ofrow) Root weight ( d r y g m ~of row) Yield ( k g l 0 h a ~)
1
2
3
4
70.0+_5.0
40.0+_3.1
91.5+_3.5
87.5+3.5
602 +_32
192 _+91
828 +_91
724 +_81
248 +_35
98 +_23
622 +_122
613 +112
158 +25
15 +_3
338 +_38
236 +_48
30
Enchytraeidae • Treatmenl(1) 20
~1'0 O O~
o
(2)
~
(3)
Oribatei 10
Acari exceptOribatel 20
~s.e
(4)
i 5 ~
o
Fig.
~ 10
45 105 165 (.June)(Aug) (Oct)
2,
5
-~.----~ .-~-~ o 45 105 165 45 105 165 Age (in days) of uptand rice
10
~t~.!..._..~'
45 105 165
Soil meso-animals after 3 years under 4 soil management practices 1986.
182 T A B L E III Number of macro-animals per m :~in the soil profile (0-40 cm) after 3 years under four soil management systems, October 1986 Macro-animal taxa
Treatment 1
Eisenia foetida Dendrobaena octaedra Pheretima hilgendorfi Pheretima sp. Philomycidae Aranea Armadillidiidae Porcellionidae
Oligochaeta
Gastropoda Arachnida Crustacea Chilopoda Diplopoda Symphylla Insecta
2
2 18 2 1 1 4 7 2 24 4
Orthoptera Tridaetylidae Dermaptera Hemiptera Cydnidae Reduviidae Diptera Coleoptera Harpalidae Staphylinidae Scarabaeidae Elateridae Chrysomelidae Curculionidae Coccinellidae
3
1 11
2
2
1 1
8
3 6
2
13
1 7
24 1 23 17
153 (17.6)
2 4 14
1 1 3 7 28 5 6
4 3 2 1
1
2
3
0.91 0.40 0.61
0.51 0.48
0.66
4
1 5 28 14 15 18 2
1 1 34 (5.4)
64 (4.7)
Values of similarities ( C}. index) between two treatments, based on the date of Table III Treatment
2 27 1 2
3
T A B L E IV
Treat ment
7
1
1
Total (SE)
4
137 (2.6)
18:~ Soil animals The population densities of 4 animal groups after 3 years under the soilmanagement practices are shown in Fig. 2, the faunal makeup of the macroanimals is summarized in Table III. High densities of the 5 animal groups were found in Treatment 1, especially Acari (Oribatei and other Acari), which maintained a high density throughout the surveyed period. In contrast, a low density of animals was found in Treatments 2 and ~ throughout the surveyed period. There was no significant difference in enchytraeids and macro-animal numbers between Treatments 1 and 4. In addition, the faunal makeup of macro-animals in these 2 treatments was very similar (C5.=0.91, Table IV). DISCUSSION The present results of soil animals obtained in 1986 agree with those of the previous 2 years (Nakamura, 1988). The tilled Treatment 3, in comparison to the direct-drilling treatments, produced the best growth of upland rice. Many authors (Wilcke, 1962; Satchell, 19581 have noted an increase in earthworms as a result of increased production of crops following fertilization. However, there were no earthworms in Treatment 3. In addition, Acari, Collembola and Enchytraeidae were also reduced in numbers until the harvest. This disagrees with other reports on the comparison of the above soil animal populations under till and no-till practices ( Stinner and Crossley, 1980; Loring et al., 1981 ). They described an initial sharp decrease in population, followed by an increase towards the end of' the growing season. The reason for the difference between the present study and the other reports is uncertain. But the absence of earthworms and persistent low densities ofenchytraeids and micro-arthropods were also observed in the previous 4 years before and after the beginning of this experiment (Nakamura, 1988; Y. Nakamura, unpublished data, 1987 ). This is thought to be mainly owing to the impact of tillage and partly to the effect of pesticide application. Tillage (moudboard ploughing, harrowing, etc.) generally decreases the abundance of soil animals (Ghilarov, 1975; Stinner and Crossley, 1980). The direct detrimental effects of tillage are partly caused by abrasive damage to the animals and partly to trapping of animals in the soil when it is inverted and the existing system of cracks and pores is destroyed. The indirect effects of tillage, such as drying of the uppermost part of the soil or removal of litter from the soil surface, are probably also of importance (Wallwork, 1976; Gill, 1969; Andren and LagerlSf, 1980; Lal and De Vleeschauwer, 1982). As to the pesticide, simazine reduces the numbers of Acari and Collembola (Edwards, 1970). Furthermore, Popovici et al. (19777 reported that atrazine, which is chemically related to simazine, can lower the numbers of Acari, Collembola, Enchytraeidae. Prot~zoa and adult insect, l)op-
184
ulations for as long as 4 months after its application. In this study, simazine was applied less than 4 months before the last measurement. The comparison of direct drilling ( T r e a t m e n t 4) with rotary cultivation (Treatment 3 ), both of which received the same pesticide and fertilizer applications, showed that direct drilling caused more changes within specific soil animal populations than the pesticide application. For example, earthworms were present under direct drilling. Furthermore, enchytraeids and macro-animals were significantly larger in number. But yield of upland rice was only 70% in Treatment 3. This is thought to be mainly owing to the effect of highest soil hardness. In Treatment 2, without fertilizer and mulch, the soil was not tilled and applied with pesticide. But the density of the measured five soil animal groups was significantly lower. This may be associated with the ground surface of soil, which was bare and exposed to the sunlight throughout the surveyed period, because of the poor growth of upland rice. In Treatment 1, on the contrary, all five animal groups, especially Aeari and Collembola were significantly larger in number. This indicates that organic mulch is beneficial for soil animals (Edwards and Lofty, 1969; Andren and Lagerlbf, 1983 ). Furthermore, mulch decreased the value of soil hardness and increased soil pH, water content and ignition loss. However, plant length and top and root weight were fairly low under direct drilling, and the yield was only 47'; of the tilled T r e a t m e n t 3. This is probably due to the slow release of plant minerals from the mulch in comparison with the fertilizer. In addition, it also suggests that measured animal groups merely live in greater abundance in better soil without contributing to soil productivity. The populations of the five animal groups studied were, however, too small for a beneficial effect to be expected. The addition of suitable organic matter for mulch is also important, because the influences on earthworm ( Graft, 1970) and Acari and Collembola ( Berg and Pawluk, 1984 ) populations vary with the quality of mulch. ('ONCI,USION
As compared with tillage in an upland rice field of Japan, direct drilling without a mulch led to an increase in soil hardness and numbers of enchyl raeids and macro-animals, but decreased rice yields. Direct drilling with an organic mulch but no fertilizer was beneficial for soil animals, but considerably decreased the rice yield. Further investigations are required concerning the quantity and quality of mulch to determine the contribution of soil animals to soil productivity. ACKNOWLEDGEMENTS
l thank Mr. M. Moriya, Mr. Y. Iizumi and Mr. H. Yamaguehi for their technical assistance.
185 REFERENCES Andren, O. and Lagerlbf, J., 1980. The abundance of soil animals (Microarthropoda, Enchytraeidae, Nematoda) in a crop rotation dominated by ley and in a rotation with varied crops. In: D. Dindal (Editor), Soil Biology as Related to Land Use Practices. Proc. 7th. International Soil Zoology Colloquium. E.P.A., Washington, D.C., pp. 274-279. Andren, O. and Lagerltif, J., 1983. Soil fauna (microarthropods, enchytraeids, nematodes) in Swedish agricultural cropping systems. Acta Agric. Scand., 33: 33-52. Bal, L., 1982. Zoological ripening of soils. Agric. Res. Rep., 850: 1-365. Berg, N.W. and Pawluk, S., 1984. Soil mesofaunal studies under different vegetative regimes in north central Alberta. Can. J. Soil Sci., 64: 209-223. Edwards, C.A., 1970. Effects of herbicides on the soil fauna. Proc. 10th. Weed Control Conf., 1970, 3: 1052-1062. Edwards, C.A. and Lofty, J.R., 1969. The influence of agricultural practices on soil micro-arthropod populations. In: J.G. Sheals (Editor), The Soil Ecosystem. Pubis. Syst. Ass., pp. 237-248. Fujikawa, T., 1970. Notes on the efficiency of a modified Tullgren apparatus for extracting oribatid mites. Appl. Entomol. Zool., 5: 42-44. Fujikawa, T., 1976. Oribatid mites in the nature farming field and conventionalfield. Edaphologia, 15:1-11 (In Japanese). Ghilarov, M.S., 1975. General trends of changes in the soil animal population of arable land. In: J. Vanek (Editor), Progress in Soil Zoology. Proc. 5th. Int. Colloquium on Soil Zoology. Academia, Prague, pp. 31-39. Gill, R.W., 1969. Soil microarthropod abundance following old field manipulation. Ecology, 50: 805-816. Graff, O., 1970. Der Einfluss verschiedener Mulchmaterialien auf den N~ihrelementgehalt yon Regenwurmri3hren im Unterboden. Pedobiologia, 10: 305-319. Kitazawa, Y., 1981. Soil animals. Kankyo-Kagaku, B-74-R 12-4, (In Japanese). Lal, R. and De Vleeschauwer, D., 1982. Influence of tillage methods and fertilizer application on chemical properties of worm castings in a tropical soil. Soil Tillage Res., 2: 37-52. Loring, S.J,, Snider, R.J. and Robertson, L.S., 1981. The effects of three tillage practices on Collembola and Acarina populations. Pedobiologia, 22: 172-184. Morisita, M., 1960. Measuring of interspecific association and similarity between communities. Mem. Fac. Sci. Kyushu Univ., Ser. E., 3: 65-80. Nakamura, Y., 1988. Effects of soil animals on soil habitat modification in nature farming (without chemical fertilizer and pesticide). In: Proc. 9th. International Soil Zool. Colloquium. Moscow. (in press). Nakamura, Y. and Tanaka, S., 1979. Vertical distribution of' Enchytraeidae in various habitats. Edaphologia, 19:1-12 (In Japanese with English summary). Nakamura, Y. and Hakoishi, T., 1981. Crop system and abundance of soil animals on Ishigaki island of subtropical zone. Edaphologia, 24: 1-10 (In Japanese with English summary). Popovici, I., Stan, G., Stefan, V., Tomescu, R., Dumea, A., Tarta, A. and Dan, F., 1977. The influence of atrazine on soil fauna. Pedobiologia, 17:209 215. Satchell, J.E., 1958. Earthworm biology and soil fertility. Soils Fert., 21: 209-219. Satchell, J.E., 1960. Earthworms and soil fertility. New Sci., 7: 79-81. Stinner, B.R. and Crossley, D. A., 1980. Comparison of mineral element cycling under till and notill practiees: an experimental approach to agroecosystems analysis. In: D. Dindal (Editor), Soil Biology as Related to Land Use Practices. Proc. 7th. International Soil Zoology Colloquium. E.P.A., Washington, D.C., pp. 280-287. Wallwork, J.A., 1976. The Distribution and Diversity o[ Soil Fauna. Academic Press, London, 355 pp. Wilcke, S.A., 1962. Untersuchungen fiber die Einwirkung wm Stallmist und Mineraldtingungauf
186 den Besatz und die Leistungen der Regenwiirmer im Ackerboden. Monogr. Angew. Entomol. 18: 121-167. Yamanaka, K. and Matuo, K., 1962. Studies on soil compaction (1). Jap. J. Soil Sci. Plant Nutr. 33:343-347 (In Japanese).