3Ainai Ma. Proceedings of International Workshop on Geographic Information System Beijing 87 [ M ]. Published by the lab of resources and environment information system , Institute of Geography, CAS. 1987.1 - 446.
4FAO. Global and national soil and terrain digital database (SOTER)[M]. World - Soil- Resources - report. 1995, 10 - 18.
5国家自然科学基金委员会,土壤学,1996年
6Ainai Ma. Proceedings of International Workshop on Geographic Information System Beijing 87 [ M ]. Published by the lab. of resources and environment information system , Institute of Geography, CAS. 1987.1 - 446.
7FAO. Global and national soil and terrain digital database (SOTER)[M]. World- Soil- Resources- report. 1995, 10 - 18.