大兴安岭不同冻土带土壤动物生态地理研究

2003年6月、8月、10月对大兴安岭不同冻土带选择沼泽、柳丛、耕地、次生林群落进行土壤动物调查，共获土壤动物39225只，隶属于4门8纲24目。由对大型、中小型及湿生三类土壤动物的数量分析可知，三类土壤动物数量的变化在群落间并不总是成正相关的关系。水平分布调查表明，中小型土壤动物的个体数量和类群数量从岛状冻土带到连续多年冻土带逐渐减少，该分布与土壤动物分布的一般规律（土壤动物分布通常符合纬度地带性分布规律，即由低纬向高纬逐渐减少）一致，但大型土壤动物的个体数量、类群数和生物量基本上从岛状冻土带到连续多年冻土带逐渐增加（即由低纬向高纬逐渐增加），湿生动物的数量也如此分布，这与土壤动物分布的一般规律不一致甚至相悖，这一特点表现出生态系统局部-区域相互关系的复杂性；土壤动物的类群数、个体数量与土壤有机质、全氮的含量呈明显的正相关；垂直分布调查表明，中小型土壤动物的个体数量和类群数量分布表现出明显的表聚性，但大型土壤动物的个体数量与生物量最大值出现在第二层；土壤动物多样性分析表明，中小型土壤动物的多样性指数从岛状冻土带到连续多年冻土带逐渐减小，而大型土壤动物的多样性指数在不同冻土带间的变化规律不明显。

GEO-ECOLOGY OF SOIL FAUNA IN DIFFERENT TUNDRAS IN DA XINGANLING MOUNTAINS

An investigation of soil fauna was carried out in swamps,willow-shrub meadows,cultivated lands and secondary forestlands in three different tundras in Da Xinganling Mountains in June,August and October,2003.A total of 39 225 individuals of soil animals,belonging to 4 phyla,8 classes and 24 orders were collected and sorted into macro,meso/micro and hygric fauna.Analysis of the populations of the three groups of soil animals did not show any consistent positive relationship between them in community.The investigation of horizontal distribution of the animals indicated a decreasing trend of the numbers of individuals and groups of meso/micro soil fauna from island tundra to the continuous tundra,which is similar to the general law of the distribution of soil fauna(that is ,the number of soil animals gradually decreased from low latitudes to high latitudes),and a reverse trend in terms of the numbers of individuals and groups and biomass of macrofauna and the population of hygrocole as well.Their inconsistent and even reversed distribution rules revealed complexity of the relationship between locality and region of(ecosystem).The numbers of individuals and groups of soil fauna were significantly and positively related to contents of organic matter and total nitrogen in the soil.The investigation of vertical distribution of soil fauna indicated that the individuals and groups of meso/microfauna were mainly distributed in the surface soil layer,but those of macrofauna peaked in the sub-layer.The analysis of soil fauna diversity indicated that the diversity index of meso/microfauna declined from the island tundra to the continuous tundra,whereas the diversity index of macrofauna did not show any obvious law of variation between tundras.