A Preliminary Study On Information System Based On ComGIS For Soil And Water Conservation Evaluation

Evaluation of soil and water conservation benefit is of great importance to the soil and water management and decision making as well as prediction of soil and water conservation progress. So it is one of important tasks of soil and water conservation research. This thesis, aiming at improving the efficiency of soil and water conservation and realizing the information-based evaluation of soil and water conservation benefit, developed an information system for evaluation of soil and water conservation benefit for Yanhe River river basin using the component-based GIS techniques.The main results are as follows:(1) Designed and developed the information system for evaluation of soil and water conservation benefit for Yanhe River river basin based on system requirement analysis. This system takes attribute database and Fundamental Geographic Information Database as background database, realizing calculation of Benefits of soil conservation by accessing the database and 6 function module: map layer management module, spatial and attribute data management module, spatial analysis module, benefit calculation module, export of report forms module, data transformation and help module.(2) Determined to select using the component-based GIS techniques that we think it as the best and ArcGIS of ESRI company that is good at generality, stability, bottom layer opening, database integration and spacial analysist to develop system by Contrastive Analysis of 3 Methods and common platforms of developing geographic information system.(3) Putted forward a techniques and methods of transforming data in this system; Transformed attribute data in Yanhe River basin were imported into the database using the VBA program language in Excel and realizing the transformation of excel data to database data and attribute data to shapefile file and coverage file to raster file.(4) Finished developing the main fuction module .The exported reports include the statistic of rainfall for many years, Year-to-year variability in rainfall data, Year-to-year variability in rainfall erosion force, statistic of rainfall erosion force for many years. Realizing the fuction of adding layer, deleting layer, zooming in , zooming out,paning, identifying and so on In map layer management module;Realizing the fuction of intersection,union,mask etc in spatial analysis module .(5) The systrm basically realized to put it into evaluating benefit of soil and water conservation for Yanhe River river basin; Finished 70% fuction of calculating benefit of soil conservation and get two factors: rainfall erosion force factor, soil erodibility factor. Aimed to finish the above calculation, we need calculate the difference values of soil erosion for two years. The established system can serve as a convenient and easy operating platform for the temporal and spatial analysis of soil and water conservation benefit, saving more human resources and materials for other professional research.