三峡库区多功能防护林体系构成与布局的思考

三峡库区多功能防护林体系主要由水源涵养林、水土保持林、防风固沙林、农田防护林、护岸护滩林、道路防护林及四旁植树等林种构成。多功能防护林布局一是要遵循不同地貌部位的立地条件和社会经济发展需求，最大限度地发挥多功能防护林涵养水源、保持土壤、改善环境等生态功能；二是根据防护对象及可能发生的自然灾害，因地制宜、因害设施布设不同的防护林林种；三是以保障库区的可持续发展为原则，使区域内的自然资源最有效、最合理地得以利用；四是在多功能防护林体系建设中，工程措施与生物措施相结合；五是生态效益与经济效益相结合，当前利益与长远利益相结合；六是在树种选择上实行乔、灌、草相结合。林种配置上，网、带、片相结合；七是以防护林为主，多林种协调发展，使三峡库区防护林体系结构整体优化。

OVERALL ARRANGEMENT OF MULTI-FUNCTIONAL PROTECTION FOREST SYSTEM IN THE THREE-GORGE RESERVOIR AREA OF THE YANGTZE RIVER

Multi-functional protection forest system(MPFS) in the reservoir area of Three-Gorge is constituted by water source forest, soil conservation forest, protection against wind and sand drifting forest, farmland protection forest, protection forest for riverside, protection forest for roades, the forest for scenery and housing. The overall arrangements of multi-functional protection forest system abide by seven principles: First to suit the site condition and the social economical requirements as to generate the ecological functions of conserving water and soil and improving the environment; Second to arrange different types of protection forests according to the protective objectives and possible nature disasters; Third to exploit the nature resources effectively and reasonablely for sustainable development of the reservoir area economy; Fourth to combine engineering and biological measures in MPFS construction. Fifth to combine ecological and economic benefits and combine short and long benefits. Sixth to integrate trees, bushes and grasses in selection of species and integrate net, belt and patch in arrangement of forest types; Seventh to optimize the structure of protection forest system in the Three-Gorge reservoir area of the Yangtze River mainly with protection forest and supplemented with other kinds of forests.