长白山地低山区土壤动物群落特征及其对环境因子变化的响应

Community characteristics of soil fauna in the low-mountain of the Changbai Mountains and its respond to the change of environmental factors

为探讨长白山地低山区土壤动物群落特征及其对环境因子变化的响应,分别于2014年春季(5月)、夏季(7月)及秋季(9月)对长白山地低山区的次生针阔叶混交林、次生落叶阔叶林、蒙古栎林和耕地土壤动物进行研究。研究表明,4个生境共获土壤动物58类,30445只,隶属3门6纲22目52科(亚目)。各生境大型、中小型土壤动物具有一定的差异性,且各生境季节变化不同。总体来看,耕地生境土壤动物密度与类群数明显低于其它3个生境,大型土壤动物的密度季节变化较显著,中小型土壤动物的密度和类群数的季节波动均较大。次生落叶阔叶林生境大型、中小型土壤动物群落多样性指数和丰富度指数均高于其它3个生境,耕地最低。中小型土壤动物多样性指数、丰富度指数季节波动较大,春季、夏季与秋季之间差异性较大,大型土壤动物季节波动较小。通过对大型、中小型土壤动物与13种环境因子进行Pearson相关分析可知,大型土壤动物对土壤温度和土壤湿度具有正向响应,其密度、类群数与土壤温度具有显著正相关关系,中小型土壤动物的密度、类群数对土壤湿度具有显著正向响应;土壤动物对pH的响应程度较低,对有机质具有显著正向响应;土壤动物对全效养分N、P、K的响应程度高,大型土壤动物的密度对速效养分N、P、K的响应程度高,中小型土壤动物类群数对速效养分N、P、K的响应程度高,对Ca、Mg的响应程度较低。

The soil fauna community characteristics of the lower Changbai Mountains were investigated, as well as their response to changes in environmental factors. Soil fauna from four habitats, including the secondary boreonemoral zone, secondary deciduous broad-leaf forest, Mongolia oak forest, and farmland in Changbai low-mountain area, were studied in the spring （May）, summer （July） and fall （September） of 2014. Overall, 30445 individuals were captured. These belonged to 3 phyla, 6 classes, 22 orders, and 52 families. The soil fauna density and their group numbers differed among the habitats with seasonal fluctuations. The structure of the farmland soil fauna community was the simplest among all habitats. Seasonal fluctuations of macro-fauna density were high. For micro-fauna, both the seasonal fluctuation in density and group numbers were high. The biodiversity analyses showed that in these biotopes, the soil fauna community in the secondary deciduous broad-leaf forest has the highest diversity and richness indices. In contrast, the diversity and richness indices were the lowest in the farmland habitat. Seasonal fluctuations in diversity and richness indices were high for micro-fauna. The differences in these indices between spring, summer, and fall were apparent, although less profound for the macro-fauna. Using Pearson correlation analyses between the macro- or micro-fauna and 13 soil environmental factors, we showed that the response of macro-fauna to soil temperature and soil humidity was positive. Especially the macro-fauna density and soil temperature have an obvious positive correlation, as well as the micro-fauna density and group number and soil temperature. Furthermore, the response of soil fauna to pH was weak, but soil fauna and organic matter had an obvious positive correlation. Finally, the response of soil fauna to Total nitrogen, total phosphorus and total potassium was strong, as well as the response from macro-fauna to available N, P, and K. Finally, the relationship between micro-fauna group number and available N, P, and K was strong, but weaker for Ca and Mg, and with a highly negative correlation to Mn.