| The author reports the study results on soil animals in the farmland environment inJining district.The research sites are located 10 kilometers north of the city of Jining , about 115°52′ east longitude , 34°26′ north latitude and 90m above sea level, drab soil typeand 7.2-7.4 pH value.In order to study the effects of crop straw burning on the soil animal communitystructure and changing regularity, four kinds of sample field were selected and foursampling sites were set up: the sample corn field (A1) and the sample soybean field (B1)with wheat straw being burnt after harvest;the sample corn field (A2) and the samplesoybean field (B2) without any burning straw. From May to December ,2004, Wesampled once a month (8 times altogether). Every sample is collected quantitatively eachlayer. The capacity of soil wreath knife is 100cm3. We collected 36 samples each month,and then separated and gathered the soil animals both in the land selecting method and theTullgren funnel method .At the same time, we alse measured the main environmentalfactors, including soil temperature, soil water content , soil pH value , soil organicsubstances and the content of nitrogen and phosphorus.After analysing all samples from these 4 sites , we find an obvious difference betweenthe quantity distribution and the constitution of soil animal communitues . It is believedthat burning straw has make both their groups and their amount of soil animals reduce toa greater or lesser degree, especially Collembola and Cryptostigmata ,which have a strongtrend to locate at the top layer of the soil .On the other hand ,the influence of crop strawburning was even stronger on corn field than on soybean field.Investigation also shows that Prostigmata, Cryptostigmata, Collembola andMesostigmata are the main groups, for 31.10%, 28.49% ,22.85% and 11.03% of the totalamount of soil animals respectively. Moreover, Coleoplera and Diptera,occupying 1.14%and 1.12% of the total amount of soil animals ,are the common groups . This 6 main andcommon groups occupy 95.73% of the total soil animals and make up the main body ofsoil animals communities in this area.The seasonal variations in soil animal communities are also very obvious. Comparingwith the contrast field , straw burning will obviously delay the peak of the communitynumber.The vertical distribution tendency of soil animals communities are more obvious , too .Most of soil animal have a trend to locate at the top layer of the soil, the amount capacityis: 49.08% in the layer 0-5cm, 29.38% in the layer 5-10cm, 21.54% in the layer 10-15cmrespectively .Straw burning will have a reducing tendency for the top layer location ofsoil animals.Using the diversity index of Shannon-wiener, evenness index of Pielou , dominanceindex of Simpson to measure the community diversity in this area , We found that thediversity of soil animal community in this area is not high . The community diversityindex in the whole district is over 1/2 lower than the largest diversity index equally .Strawburning also sort of lowered the diversity index .According to the Jaccard's similarity coefficient and lowest percentage similaritycofficient , the similarity cofficients among the four sites and all animal communities inthe whole area are higher and very similar .This is because although crop straw burninghas a greater influence on soil animal communities ,it mainly influences their amount .Sotheir groups are still more consistent.By further study of soil Oribatida .We find that straw burning greatly influence thenumber of Oribatida especially the sort of them. The results by MGP analysis indicatedthat straw burning greatly influence M-group.Investigation also shows that crop straw burning has a stronger influence on soilenvironment factors ,soil nutrient content ,and crop yield ,too .Crop straw burning willmake soil temperature ,soil pH value rise ,and make soil water content ,the amount oforganic substances ,nitrogen ,phosphorus lower ,and finally make the corn crop andsoybean crop reduce.
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