| Agricultural resources and environment is the most primary condition for human being living and development, and it also the basis for agriculture and the guarantee of sustainable development for economy and socienty. In this paper, based on the object influencing agricultural resources and environment database in Hebei Province and the technology of GIS and SOTER, the agricultural resources and environment database including soil/land, landform, geomorphology, vegetation and social economic and so on, was constructed through integrating different sources data. Hereon, soil erosion risk and the spatial distribution of soil carbon and nitrogen were evaluated and analyzed. These provided the technological support for the sustainable use and development of agricultural resources and also provided the assistant decision service for protection of the agriculture ecological environment.Through systematical analysis of the theory and methods, the agricultural resources and environmental database of Hebei province with a scale of 1:50,0000 was established by integrating the data dispersion in different departments, space and time, projection and coordinate system, criteria and standard. The database consisted of five sub-database such as the base geographic information database, soil database (SOTER), land use database, climate database and agricultural production management and social economic database.Soil erosion risk and the spatial distribution of soil carbon and nitrogen were evaluated and analyzed based on the agricultural resources and envrironmental database.Modified logistic growth model with two parameters could simulate soil particle-size distributionand make the conversion of soil texture scheme from the Katschinski to the USA. With the formula method, the soil erodible K value was calculated and the K value map with a scale of 1:50,0000 well made with GIS. Meanwhile, the area of soil erodible K value between 0.25 and 4.0, the erosion and relative erosion soil account for about 58.6% of the total area in Hebei province.A simple and convenient arithmetic formula was developed to calculate the rainfall erosivity by using the precipitation data of meteorologic station. The basic formula was Y=0.6698x~1.865 (R~2=0.7866). A best method for predicting rainfall erosivity was got by comparing the different semivariogram function model with interpolation methods on the basis of trends analysis. Semivariogram function named Gaussian model and interpolation method named the disjunctive kriging were the best models to simulate the rainfall erosivity. The rainfall erosivity database of high spatial resolution was constructed at the accurate of 250 m × 250 m.The correlative data was selected from the established database of agricultural resources and environment, and the soil erosion risk was quantified by using RUSLE model. Soil erosion intensity of Hebei Province was devided into six class, such as very low, low, medium, high, very high and violent. The area and percentage to whole province in different erased soil was 108,000 km2 and 58.2%; 35 000 km2 and 18.9%; 11 000 km2 and 6.1%; 8 183 km2 and 4.4%; 10 000 km2 and 4.4%, 12 000 km2 and 6.8%.Based on the SOTER database and GIS technology, the organic carbon and nitrogen density ofdifferent soil groups and their spatial distribution were calculated and analyzed. The results indicated that the average density of soil organic carbon and nitrogen in Hebei province was about 10.83 kg·m~-3 and 1 070.96 g·m~-3, respectively, and the C/N ratio 9.99. Based on the soil erosion risk, the losing storage of carban and nitrogen in Hebei province for rainfall erosivity was 1.95 x 10~6t and 1.62 x 10~5t per year, respectively, and mainly dirtributed in the low-mountain-knap of Yanshan and Taihangshan. The organic carbon and nitrogen density and storage distributed in different districts between 1980's and 1990's changed with time and spatial. They both had the same tendency. Their changes tended to increase from north to south.
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