新疆农田不同施肥区土壤昆虫群落丰富性与多样性

 【目的】在新疆国家灰漠土土壤肥力与肥料效益长期监测基地，对10种施肥处理，即（1）撂荒（不施肥、不耕作、不种植，Aband.）、（2）对照（种植、不施肥，CK）、（3）施氮肥（N）、（4）施氮磷肥（NP）、（5）施氮钾肥（NK）、（6）施磷钾肥（PK）、（7）施氮磷钾化肥（NPK）、（8）施氮磷钾化肥+有机肥（有机氮和化肥氮的比例为7﹕3）（MNPK）、（9）化肥用量增加50%配施有机肥（1.5 MNPK）、（10）化肥配施秸秆(SNPK)与新疆灰漠土区农田土壤昆虫群落之间的关系进行研究。【方法】采用改良干漏斗（Modified Tullgren）分离土壤（0～20 cm）中的土壤昆虫，同时利用陷阱法收集活动在地表的各类土壤昆虫。【结果】两种方法共获得土壤昆虫4 915只（未知标本128只），隶属9目33科。大型土壤昆虫个体数和类群数在Aband.处理中分布最多，中小型土壤昆虫则分别在N和PK处理中分布最多；MNPK处理土壤动物组成最丰富，N处理土壤动物分布最均匀。农田土壤昆虫类群分布受施肥影响极其显著（X0.05（9）=23.38，P＜0.005），Aband.区土壤昆虫群落与其它施肥处理土壤昆虫群落差异极显著（P＜0.01）。利用非度量多维标度分析法对土壤昆虫群落分类排序，则灰漠土土壤昆虫群落划分为5组，即NPK、MNPK、1.5MNPK和CK为一组，NP和PK为一组，NK和N为一组，SNPK和Aband.各为一组，表明土壤昆虫分布与肥料性质有关。主成分中前两个主成分解释总变量的98.51%，其中第一主成分反映了单施N肥和SNPK还田对土壤昆虫群落具有促进作用；第二主成分反映了1.5MNPK对土壤昆虫群落促进作用，表明施肥处理对土壤昆虫类群影响不平衡。【结论】新疆灰漠土区，肥料的种类与性质影响着土壤昆虫类群多样性与丰富性，且其影响具有不均衡性。

Abundance and Diversity of Crop Soil Insect Community at Different Fertilizer in Xinjiang

Grey desert soil was a representative of aridity and hungriness belt soil. 80% area of was distributed at Xinjiang. National grey desert soil fertility and fertilizer efficiency long-term monitor site，which built at 1990 was one of 9 National soil fertility and fertilizer efficiency long-term monitor site, its area was 468m2. There were 10 types of fertility treatment, namely abandonment （aband.）, no-fertilizer（CK）, nitrogen fertilizer（N）, nitrogen and phosphor fertilizer（NP）, nitrogen and potassium fertilizer（NK）,phosphor and potassium fertilizer（PK）,nitrogen and phosphor and potassium fertilizer（NPK）, NPK with organic matter（fertilizer N : organic N =3:7）（MNPK）,150% NPK with organic matter（1.5 MNPK）, NPK with straw(SNPK). The effect of different fertilizer treatments on soil insect community at the grey desert soil district in Xinjiang was investigated in Sept. 2004, 90 soil samples and 100 pitfall had been collected and 4915 soil insects（128 unknown） individuals, belonging to 9 Orders and 33 families were obtained by pitfall traps and modified Tullgren methods. The result showed that the number of individual and group, the macro fauna both reached their peaks in abandonment, while mesofauna and micro fauna in nitrogen fertilizer（N） and phosphor and potassium fertilizer（PK）respectively . Of the 10 treatments, most dominant of soil insect composition was in MNPK, most evenness of was nitrogen fertilizer（N）.The result by Kruskal- Wallis test indicated that the distribution of the crop soil insect was significantly impacted by different fertilizer treatments （X0.05（9）= 23.38，p < 0.005）,soil insect group of the abandoned was significantly different from that of others fertilizer treatments. The soil insect community were divided into five group by Non-matric Multi-Dimensional Scaling（NM-MDS）analysis: （1）NPK,MNPK,1.5MNPK and CK ,（2）NP and PK，（3）NK and N，（4）SNPK and（5）aband., indicated that distribution of soil insect was related to fertilizer character. In the principal component analysis ,two factors explained 87.455% of the total variation among 10 treatments, the factor one explained nitrogen fertilizer（N）and NPK with straw （SNPK）positively effected, while second factor explained the aband. positively affected on soil insect community, that showed the diversified fertilizer did not evenly effect on the soil insect community.