银川不同湿地陆生昆虫群落多样性与稳定性

【目的】调查和分析银川不同湿地陆生昆虫群落结构组成、功能多样性及其稳定性变化。【方法】2016年5-10月选取银川黄河湿地(HH)、鸣翠湖湿地(MCH)、芦花台湿地(LHT)、水洞沟湿地(SDG)4种湿地生境，采用棋盘式扫网和陷阱捕捉的方法进行昆虫采集。根据调查数据进行昆虫群落结构多样性分析、主成分分析和聚类分析。【结果】4种湿地生境共采集昆虫38 668头，隶属13目97科370种。双翅目、同翅目、膜翅目在4种生境中均为优势类群。植食性(Ph)昆虫功能团的科数和种数在4种生境昆虫群落中占比均最大。植食性-中性昆虫(Ph-Ne)间个体数在4种生境下均存在显著负相关(P<0.01)；植食性-捕食性昆虫(Ph-Pr)间个体数在MCH生境下存在显著正相关(P<0.05)；中性-捕食性昆虫(Ne-Pr)间个体数在MCH生境下存在显著负相关(P<0.01)，在LHT生境下存在显著负相关(P<0.05)；4种功能团结构的其他组合的个体数在4种生境下均不存在显著相关性。主成分分析结果表明，捕食性类群是4个类群中影响构成昆虫群落组成的主要成分。同种功能团在4种生境下的多样性分析结果表明，捕食性功能团(Pr)与寄生性功能团(Pa)在4种生境群落中的群落丰富度、均匀程度［辛普森指数(Simpson index)］差异性显著(P<0.05)，而植食性功能团(Ph)与中性功能团(Ne)的群落丰富度、均匀程度的差异性不显著(P>0.05)；中性功能团(Ne)在4种生境群落中个体出现的不确定程度［香农-维纳指数(Shannon-Wiener index)］差异性不显著(P>0.05)，在4种生境的均匀度指数(Pielou evenness index)差异性显著(P<0.05)，其余3个功能团在4种生境下的香农-维纳指数均差异性显著(P<0.05)，在4种生境下的均匀度指数均差异性不显著(P>0.05)。4种生境昆虫群落特征指数的聚类分析分为2类，永久性湿地HH和MCH为第1类，季节性湿地LHT和SDG为第2类。Ss/Si和Sa/Sp两个稳定性指标均显示MCH昆虫群落稳定性最高，4种生境昆虫群落最稳定的时期是5和9月。【结论】双翅目和膜翅目昆虫在银川不同湿地生境中均为优势类群，可作为环境指示参考；昆虫群落稳定性最好的湿地类型为永久性湖泊湿地；不同生境昆虫群落多样性随季节时序变化，在银川最稳定的时期是5和9月。气候因子、环境因素如何驱动各湿地昆虫群落多样性及稳定性的变化因素还有待开展研究。

Diversity and stability of terrestrial insect community in different wetlands in Yinchuan,Ningxia,Northwest China

【Aim】 To investigate and analyze the changes in the structural composition, functional diversity and stability of terrestrial insect communities in different wetland types in Yinchuan, Northwest China. 【Methods】 Four wetland habitats including Yellow River wetland (HH), Mingcui Lake wetland (MCH), Luhuatai wetland (LHT) and Shuidonggou wetland (SDG) were selected based on the experimental design, and sampled from May to October, 2016. Insects were collected by chessboard sweeping and pitfall trapping approaches. Insect community structure diversity analysis, principal component analysis and cluster analysis were conducted based on the survey data. 【Results】 A total of 38 668 insects belonging to 370 species, 97 families and 13 orders were collected from the four wetland habitats in Yinchuan. Among them, Diptera, Homoptera, and Hymenoptera were the dominant groups in all the four habitats. Phytophagous insects accounted for the largest proportion in the family and species level of the insect communities among the four wetlands. The individual number showed a significantly negative correlation between the phytophagous and the neutral insects (Ph-Ne) in the four habitats (P<0.01). In the MCH habitat, the individual number showed a significantly positive correlation between the phytophagous and the predatory insects (Ph-Pr) (P<0.05), while a significantly negative correlation between the neutral and the predatory insects (Ne-Pr) (P<0.01). Additionally, in the LHT habitat, the individual number showed a significantly negative correlation between the neutral and the predatory insects (Ne-Pr) (P<0.05). Finally, the individual number in other combinations among the four functional groups did not show any significant correlation in all the four habitats. The predatory species group was the main component that affected the composition of the insect community based on principal component analysis (PCA). For the diversity analysis of the same functional group in the four habitats, there was a significant difference between the predatory (Pr) and the parasitic (Pa) functional groups based on the Simpson index (P<0.05), while there was no significant difference between the phytophagous (Ph) and the neutral (Ne) functional groups based on the Simpson index (P>0.05). Based on the Shannon-Wiener index, there was no significant difference among the neutral (Ne) functional groups in the four habitats (P>0.05), while there was a significant difference among the neutral (Ne) functional groups in the four habitats based on Pielou evenness index (P<0.05). Based on the Shannon-Wiener indices for the other three functional groups, there were significant differences among the four habitats (P<0.05), while they had no significant differences in the Pielou evenness index (P>0.05). The cluster analysis showed that the four types of wetlands were divided into two categories based on the characteristic index of insect communities, the first was permanent wetlands including HH and MCH, and the second was seasonal wetlands including LHT and SDG. Based on the stability index, the highest stability was found in the MCH habitat. The most stable periods for insect communities in different habitats were in May and September annually. 【Conclusion】 Diptera and Hymenoptera are the dominant groups in different wetland habitats in Yinchuan, and can be used as environmental indicators. The insect communities in the permanent lake wetland show the highest stability. The diversities of the insect communities in different habitats change with the seasons, and the most stable periods are in May and September annually. How the climatic factors and environmental factors drive the diversity to change and what factors affect the stability of insect communities in different wetlands remain to be studied.