吉林黑土区不同施肥处理对农田土壤昆虫的影响

Effect of different fertilizer treatments on crop soil insect community at Black soil district in Jilin Province

为研究不同施肥处理与农田土壤昆虫群落之间的关系,对吉林黑土区不同施肥处理对农田土壤昆虫群落的影响进行了研究。在12个处理小区内,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+有机肥处理(有机N和化肥N的比例为2∶1)(M1NPK)、(9)增加50%用量化肥配施有机肥(1.5MNPK)、(10)化肥配施秸秆(SNPK)、(11)玉米、大豆2:1轮作,施肥量同处理8(Rot)、(12)施氮磷钾化肥+有机肥处理(有机N和化肥N的比例为1∶1)(M2NPK),共采集144个定点土壤样品。通过手捡法和改良干漏斗法(ModifiedTullgren)共获得土壤昆虫9922只(未知标本187只),隶属9目48科。调查结果显示,12种施肥小区内,大型土壤昆虫个体数和类群数依次是:ABAND>NP>N>1.5MNPK>Rot.>PK>NK>NPK>M2NPK>CK>M1NPK>SNPK,N>NK>ABAND=1.5MNPK>NP=NPK>PK>CK=Rot.>M2NPK=M1NPK>SNPK;中小型土壤昆虫数依次是ABAND>1.5MNPK>PK>M2NPK>CK>Rot.>NPK>SNPK>NK>NP>N>M1NPK,Rot.>NPK>ABAND=NP=1.5MNPK=PK=NK=M2NPK=CK=M1NPK=SNPK>N。大型土壤昆虫个体数和类群数撂荒中分布最多,中小型土壤昆虫则分别在撂荒和轮作中分布最多。多样性分析表明,1.5MNPK处理中大型农田土壤昆虫组成最丰富,M1NPK处理中小型农田土壤昆虫组成最丰富;CK处理与其他11处理之间群落相似程度最小,Rot.与其他处理之间的群落相似程度较大。KruskalWallis检验法分析表明,施肥对农田土壤昆虫分布影响极显著(X0.05(11)=10.25,p<0.05),反映出不同施肥对土壤生态系统内部环境,进而对土壤动物群落产生的影响。多元统计分析表明,轮作对土壤昆虫优势类群具有负向作用,而M2NPK则具正向作用。各种施肥对农田土壤昆虫影响不平衡,其中对农田土壤昆虫个体数影响最大,对中小型土壤昆虫均匀性影响最小。

The effect of different fertilizer treatments on soil insect community at the black soil district in Jilin province was investigated in Aug. 2003. In 12 types of treatments, namely abandonment（ABAND）, no-fertilizer treatment（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 = 1：2）（M1NPK）,150 % NPK fertilizer with organic matter（ 1.5 MNPK）, NPK with straw （SNPK）, Rotation（maize ： soybean = 2： 1） and the quantity of fertilizer being the same as（ M1NPK）（Rot）, NPK fertilizer with organic matter（fertilizer N： organic N = 1 ： 1）（ M2 NPK）, 144 soil samples had been collected and 9922 soil insects（ 187 unkown） individuals, belonging to 9 Orders and 48 families were obtained by hand-sorting and modified Tullgren methods. The result showed that the number of individual and group, the macrofauna reached their peaks in abandonment and N treatment, respectively, while mesofauna and microfauna in abandonment and rotation treatments showed that the distribution of the soil insect was related to fertilizer treatment. Of the 12 treatments, most dominant soil insect composition of the macrofauna was in 1.5MNPK, while mesofauna and microfauna were in M1NPK, the similarity coefficient between CK and other treatments was general low, and between rotation and other treatments general greater. The result by Kruskal- Wallis test indicated that the distribution of the crop soil insect was significantly impacted by different fertilizer treatments （X0.05（11） = 10.25,p 〈 0.05）, indicating that the soil fauna community was affected by different fertilizer treatments, of which the rotation had negatively effected, and M2NPK positively effected on the dominant soil insect group, showing the effect of different fertilizers on inner environment of the soil ecosystem and then proceeded to the soil fauna community. The result by principal component analysis showed that the diversified fertilizer did not evenly effect on the soil insect, of which the greatest the number of cropland soil insect individuals, the least evenness of meso- and microfauna.