盐池四墩子拟步甲昆虫群落组成与环境因子的相关性

2009年3-10月，对宁夏盐池四墩子不同植被类型和人工干扰强度的荒漠草地的拟步甲昆虫群落结构及其环境因子特征进行了调查, 采用多样性指数和典范对应分析(CCA)研究了昆虫群落与环境因子之间的相关性.共收集拟步甲10属20种，5431只，以弯齿琵甲、克小鳖甲和蒙古漠王占优势，分别占总数的47.30%、39.90%和3.59%.CCA分析表明：拟步甲与环境因子之间的相关性高达100%，提示盐池四墩子环境因子变化影响拟步甲的分布，植物群落多样性、植物生物量和土壤含水量对拟步甲昆虫群落的分布影响最大；从物种的分布状况看，谢氏宽漠王对环境最为敏感；小丽东鳖甲、宽突东鳖甲、尖尾东鳖甲、宽腹东鳖甲次之，与植物生物量、植被盖度呈负相关，戈壁琵甲、中华砚甲、网目土甲和淡红毛隐甲与植被密度和土壤含水量呈正相关，蒙古漠王、克小鳖甲、小皮鳖甲和异距琵甲与植物群落多样性呈正相关，奥氏真土甲、弯齿琵甲和达氏琵甲与植物生物量和植被盖度呈正相关；相关和回归分析结果也显示，拟步甲群落的活动密度与土壤含水量极显著正相关(r=0.943,P=0.005).同时，排序反映了拟步甲对生态环境的需求以及其在不同资源维上的生态分化现象.

Darkling beetle community structure and its relations with environmental factors in Sidunzi of Yanchi, Ningxia, China

From March to October 2009, a field survey was conducted on the darkling beetle community structure and related environmental factors in the desert grasslands with different vegetation cover and human disturbance intensity in Sidunzi of Yanchi, Ningxia, China. By using diversity index and canonical correspondence analysis (CCA), the relationships between the beetle community structure and related environmental factors were analyzed. A total of 5431 individuals were collected, belonging to 20 species and 10 genera. Blaps femoralis femoralis,Microdera kraatzi kraatzi, and Platyope mongolica were the dominant species, accounting for 47.30%, 39.90%, and 3.59% of the total, respectively. CCA explained 100% of the correlations between the beetle species and related environmental factors, suggesting that the occurrence of the beetle species had close relations to the changes of related environmental factors. Among the environmental factors, the Shannon diversity index of plant community (HP), plant biomass (BP), and soil water content (SW) affected the beetle species occurrence most. The occurrence frequency of Mantichorula semenowi, Anatolica amoenula, A. sternalis, and A. gravidula was negatively correlated with BP and plant coverage (CP), and that of B. gobiensis, Cyphogenia chinensis, Gonocephalum reticuluatum, and Crypticus rufipes was positively correlated with plant density (DP) and SW. The distribution of P. mongolica, M. kraatzi kraatzi, Scytosoma pygmaeum, and B. kiritshenkoi showed a positive correlation to HP, andthat of Eumylada oberbergeri, B. femoralis femoralis, and B. davidea showed a positive correlation to BP and CP. There was a significant positive correlation (r=0.943, P=0.005) between the beetle activity density and SW.The CCA ordination showed that the darkling beetles had different demands for multidimensional ecological resources in desert and semi-desert ecosystems.