Study On Eco-geographical Characteristic Of Soil Animals In Main Greenlands Of Changchun

Soil animals are special composition in ecosystem that play an important role in the substance circulation and energy transform. In the recent time, many scholars study soil animals, but many of them focus their studies on natural and semi-natural ecosystem such as forest, grassland, farmland and so on. They held the composition, distribution and environmental characteristic of soil animals from tropic to temperate zone, from plain to mountain. The dissertation studies the composition and distribution characteristic of soil animals in the urban greenlands, discusses the effect of environment on soil animals and compares characteristic of soil animals between urban greenlands and natural ecosystem. Six categories of primary representational greenlands are chosen in the six districts of Changchun. They are park greenland, campus greenland, resident greenland, street greenland, factory greenland and nursery greenland. We get a series of data about soil animals and soil environment. Soil animals in the six categories of greenland are 5118 and belong to 28 groups, 3 phyla. In the soil animals, there are 1094 large-size soil animals that belong to 24 groups, 4024 middle-small-size soil animals that belong to 20 groups. The dominant groups include Formicidae, Collembola, Oribatida and Gamasida. The common groups include Coleoptera,Staphylinidae,Enchytraeidae,Gastropoda. The number of rare groups is 10 and that of seldom groups also is 10. The horizontal distribution of soil animals is unequal because of difference in each greenland habitat. Among the individual numbers of soil animal, that of campus greenland is the most(1654); that of nursery greenland is secondly(1201); then, they are park greenland(828), resident greenland(669), factory greenland(508) and street greenland(258). There are small difference in the group of soil animals, and 20 groups both in the campus greenland and resident greenland, 19 groups in street greenland, 18 groups separately in the nursery greenland, park greenland and factory greenland. The characteristic of vertical distribution of soil animals is that individual number and group number of soil animals decrease with the increasing of soil depth. Individuals and groups have characteristic of surface assembling. The abundance and diversity index of soil animals are positive correlation, but the abundance and the dominance are negative correlation. Physical and chemical character of soil affects differently soil animals. In the dissertation's studies, the correlation between soil animals and the temperature of soil isn't very obvious; individual and group number of soil animals and water content in the soil are positive correlation, especially in 0-10cm soil layer. In alkalescency,the correlation between individual and group number of soil animals and pH is negative correlation. The correlation between individual and group number of soil animals and organic matters is positive correlation. It is most obvious in 0-10cm soil layer. In general, the correlation between individual and group number of soil animals and physical and chemical character of soil is the most obvious. The most difference of composition and distribution of soil animals between urban greenlands and natural ecosystem is individual and group number. Soil animals in urban greenlands are less than that in natural ecosystem greatly, which is very obvious in the primary greenlands in Changchun. Because Changchun is modern urban that belongs to human habitat, and urban ecosystem is affected greatly by human. During development and building the urban, many human activities such as destroying of trees, letting of rubbish and so on, have destroyed the balance of nature ecosystem and the habit of soil animals. In a word, changes of environment restrain soil animals from subsistence.