Study On The Efficient Spatial Allocation Of The Ecological Forest System In Minjiang Watershed Based On Geomatics

The data used in the paper were got through the collection of the natural conditions and socio-economic conditions and the ecological forest system construction in Minjiang Watershed with the help of survey and geomatics technology. To prevent soil erosion and keep water conservation, it defined the optimum forest coverage of Jianxi River, Hutongxi River, Shaxi River and Mingjian watershed in this paper at the basis of analysis the current status and dynamical changes of land use. The optimum proportion of forest types structure and the spatial allocation programming of the ecological forest in Minjiang Watershed was determined with the help of the analysis matrix which was built with the help of the combination of quantitative analysis and qualitative judgment. All these will provide technology support and theoretical guarantee for the reasonable management of the ecological forest system in Minjiang Watershed. Conclusion in this paper mainly include:(1)There are much factors affecting the extraction of the thematic information of forest types. Base on the spectral characteristics of forest types, the forest types which were larger differences in spectral characteristics were extracted with the help of the expert classification knowledge, the classification model with the appropriate value of spectral and the help of the stratified separation methods. The forest types in Minjiang watershed which were no notable differences in spectral characteristics were extracted with the help of supervised classification. To promote the precision of the classification, some partial forest types thmatics information were extracted by artificial interpretation. The results showed that the interpreter accuracy of the woodland of 1986 and of 2003 was 81.3% and 86.7%, the forest of 1986 and of 2003 was 79.5% and 87.3%.(2) From 1986 to 2003, the overall change of the ecological forest woodland in Minjiang Watershed is:The areas of the Chinese fir , pinus massoniana , mixed forest and bamboo increase,but the shrub and ecomical forest decreased, especially the most extent of increasement is pinus massoniana. The main factor of the dynamical change of the ecological forest in Minjiang Watershed was the mutual change among the broadleaf, Chinese fir, pinus massoniana and mixed forest, and there was relatively small change in other types.(3) The VARI was first used in the vegetation coverage model which was used to simulate the vegetation coverage in Minjiang watershed, and effectively promoted the precision of the model , the relative coefficient of the model was 0.868 .The precision of the model was 83%.(4) Spatial analysis and hydrological analysis expansion module of Arcview were used, the equivalence line of rainfall were inserted by use of IDW. The rainfall of each quarter in Minjiang watershed were gained. Combining the rainfall of each month measured in many years with quarterly...