| Soil animals are important consumers and special decomposers in terrestrial ecosystem, and they are unusually indicative to ecosystem. By applying the ideal and researching means of ecology, this paper deals with the influence of heavy metals pollution on the structure of soil animal community. The urban ecosystem of Kaifeng is made as the studying area in the paper, and the soil of the ecosystem is taken into 5 sample areas: cropland, urban green land, residential land, culture & education land and industrial land. The collection of the soil sample had been done in May of 2004, and the soil animals sample had been collected in September of 2004. Based on the data of soil animals and soil physicochemical properties, the paper uses soil zoology and ecological theory and metering method to analyze the particularity of the soil animal communities in the five different land use types, and discusses the response of soil animals to the soil pollution. This text includes five parts. Part â… The course, existing problems and main research fields in the future of soil zoology are introduced and analyzed. The important meaning of this task is also pointed out. Part â…¡ This part is the general introduction of the natural environmental conditions, the urban evolution and the social economic situation of Kaifeng city which are important environmental factors influencing the composition and quantity of soil animals. Part â…¢ The main methods of soil animals and soil physicochemical properties in this study are introduced. Part â…£ By counting the quantity of soil animal individuals and groups in each sample area, this paper analyze and research the dominant and frequent soil animal groups, biodiversity of the soil animal communities, vertical distribution in soil profile, and resemble of soil animal communities, the heavy metal concentration of earthworms from different sampling areas in Kaifeng. The relationship between soil animals and soil physicochemical properties is analyzed by stepwise linear regression based on 6 indexes of soil physicochemical properties and 5 types of soil animals in the paper, which respectively include soil organic matter, pH, content of Cd, Pb & As in soil, complex polution index and quantity of soil animals and groups, dominance index, diversity index, evenness index. Part â…¤ Some main conclusions are summarized as follows: First: The composition of the soil animal communities is different in every land use types, and the dominant and frequent groups are different too. The dominant groups in cropland are Collembola,Prostigmata and Nematoda, and their frequencies are respectively 50.2%,16.0%, 18.7%. Both the urban green land and the culture & education land have the same dominant groups as cropland, and their frequencies are respectively 48.0%, 17.5%, 21.4% and 19.1%, 32.2%, 36.8%. The dominant groups of residential land include Collembola and Prostigmata, and their frequencies are 45.3%, 23.9%. The dominant groups of industrial land consist of Collembola and Nematoda, and their frequencies are 83.4% and 12.5%. Second: Vertical distribution laws of the soil animals are different in the sampling areas. The surface aggregation in the cropland and the urban green land is obvious, but the surface aggregation wakens in the residential land, the culture & education land and the industrial, especially the superior kinds. Third: The quantity of soil animals is decreased with the increasing of soil's pH. The diversity index and evenness index of soil animal communities are obviously negatively correlated with the pollution of heavy metals. The abundance of soil animals do not relate positively with the amount of soil organic matter. Forth: The big animals, earthworms, have a strong ability to acculate heavy metal elements, especially cadmium and arsenic are significantly accumulated in their boy from where the area is contaminated seriously. The content of cadmium, lead and arsenic in earthworms relates proportionally to the contents in the soil.
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