The Construction And Application Of Soils And Terrain Digital Databases For County Level In Hainan

Four typical area-Danzhou, Baoting, Dongfang and Qiongshan, were chosen as four windows to establish Soils and Terrain Digital Databases (SOTER) at a scale of 1:25 thousands, and research the construction and application of SOTER at large-scale, and develop the methodology of SOTER. The rule and structure of small-scale SOTER were modified properly for the requirement of large-scale SOTER. The result showed as follows:1. It was very important step for the database quality to collect system data,, sothe data collection should be carried out the unity, the purpose, and the dominant principle.2. The attached databases (including the information of climate, vegetation,land utilization) were important component for SOTER. It provided extensive data source for SOTER application.3. The SOTER including the graph material, the attribute database as well asthe attached database was more surpass than any formerly kind of soil resources expressions and appraisal methods. The SOTER could be expanded and renewed. So between each kind of scale was compatible, and series scale SOTER system could be formed.4. With the increase of the scale, the highest-level constituents of a SOTERunit, i.e. the terrain, would be gradually lost importance. SOTER unit will become delineations of soil entities. With the information on terrainbecoming incorporated in the soil attributes. Hence SOTER at large scale required more detailed information on soils for practical applications.5. The SOTER could be extensive used. It not only could offer the singleessential graphic documents for a special research, but also could export professional graphic documents under the support of other correlation computer software model.6. On the basis of SOTER, running SWEAP could get some conclusion. Thesoil erosion in Hainan mainly occurred in sloping land and steep land. For these areas, terracing or strip cropping could be suitable to reduce soil erosion.7. For the whole island of Hainan, there were higher soil erosions in themountainous areas of centre Hainan, and there were lower soil erosions in the coastal area of north of island. Soil erosion spatial distribution were identical with Hainan landform.8. It was credible and useful that SOTER database was established withSOTER methodology and Hainan reality.