Geographical Distribution And Subareas Of Spiders Community In Rice Ecosystem Of China, Based On GIS

It was reported for the first time that the geographical distribution of spiders in rice ecosystem was studied using GIS technology in this paper.Investigations on the structure and character of spider communities in rice field of China were carried out in 1999,which the collected data were saved and analyzed using GIS technology in following 4 aspects: geographical distribution of paddy fields spiders, the number of spiders species in different regions, the number of the populations of spiders and their dominant spiders in different regions, frequency of paddy fields spiders in different regions under different ecological factors. The major results are as follows:1 .The spatial database were set up using the GIS technology in this paper. The information was got and saved in GIS database after the orignal data was analyzed. The data is as follows: (1) attributable data ;(2) thematic maps.2. It was displayed directly into maps that spiders data were collected from117 samples in rice fields of China during 1999. The thematic maps of geographical distribution of main spiders in rice field of China were analyzed.The families, Lycosidae, Linyphiidae, Theridiidae and terahnathidae, could be found in rice fields of all over the country. The genera, Tetragnatha, Clubiona,Pardosa, could be found in rice fields of all over the country. The species, such as Pirata subpiraticus, Tetragnatha maxillosa, Ummeliats insecticeps and Coleosoma simon, could be found in rice fields of all over the country. The dominant species, Tetragnatha maxillosa, Pirata subpiraticus, could be found in rice fields of all over the country. A majority of species could only be found inthe south of Qinlin-Huaihe in China.3. It was interpolated spatially into digital images using GIS technology that spiders data were collected from 117 samples in rice fields of China during 1999. The digital images were analyzed. The number of the population and the composition spiders community and their dominant species spiders in rice fields are different in the different regional. The number of the population and the dynamic of spiders community and their dominant species of spiders in the ricepaddy are higher in the south of Qinlin-Huaihe than that in the other regions.4. A research on frequency of spiders under five ecological factors which included temperature, rainfall, sunlight, no-frost and altitude was made. The ecological factors were graded. In terms of the grades, the number of the samples were calculated and the frequency of spiders were analyzed. There were differences on the number of population and density of spiders community in the different habitats. The proportion of the spiders distribution groups in spider community was changeable as a result of the variation of the habitat environmental factors, which also brought about the changes of the spiderpopulation's frequency. The relationship about the comp in species of spider community between their habitats was discussed in this paper.5. Four areas of endemism were identified for spiders within rice fields of China based on the geographical distribution of spiders in the rice fields in China.The objective of this study is to develop a new approach for spiders population in large-scale by using geographical information system (GIS),which could be given scientific foundation for protection and management of paddy fields spiders to provide directions in controlling rice pests by using spiders as an agents of bio-control in the rice ecosystem.