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The accuracy of GIS data is important in GIS application. In this paper, a fictitious case and an example were used to discuss the relationship between accuracy of land vegetative cover index and accuracy of image classification, and this relationship was explained by mathematics. The accuracy of land vegetative cover index rested with the accuracy of image classification, but had no direct relations with total classification accuracy. User accuracy and producer accuracy had more direct control on the accuracy of land vegetative cover index than total classification accuracy; and hence, they could not be ignored in the image classification. To improve the accuracy of land vegetative cover index, user accuracy and producer accuracy of the same land type should be consistent to the greatest extent.

With plot cruising and rout investigation methods, 36 species of ectomycorrhizal fungi associated with oaks were found in natural secondary oak forest in Dandong district of Liaoning Province. They were subordinated to 7 familyies, 13 genera. Studies on the relationship of the ecological distribution of mycorrhizal fungi with tree species, tree age and seasons showed that 29 species mycorrhizal fugi preferred to grow with Q. mongolica, The species of Russulla were associated with a wider tree ages of oak, and the species of Amanita were most likely to grow with old tree. July and August were the occurrence peak of mycorrhizal fungi. 75% species occurred in July, and 100% species occurred in August. The relative density of the occurrence number was the highest in mid-August (19.5%) and last-August (18.4%).

Land classification is the base of land evaluation, land planning and land management, and plays an important role in the sustainable development of forestry resource. Ecological land classification (ELC) is the main approuch and direction of land classification. Along with the development of landscape ecology and 3S techniques, developing of ecological classification system (ECS) becomes the keystone of ELC. The definition, history, basic characteristics of ELC, the theory of ECS and its' prospects were systematically reviewed in this paper. The prospects were also described for the development of ECS methodology and the application of ELC. The general direction of ecological land research, which was a multi-factors and multi-levels syntheses based on the multi-objects administration of resource (forest, land and waters), was the combination of quantificational and qualitative research. It is necessary to carry out relevant researches in China.