长江上游绿色生态屏障建设的基本途径及其生态对策

Some Basic Ways and Ecological Measures of Establishing the Green Ecological Protective Screen for the Upper Reaches of the Changjiang River

本文综合分析了长江上游地区的生物多样性、水土流失、自然灾害、水资源、土地沙化以及农业生态环境等方面的现状及其变化,论证了构建长江上游绿色生态屏障的必要性和可行性。从因地制宜、乡土树种筛选、人工林纯林化、现有林保护及造林规划等方面充分论述了现实存在的问题及误区。最后,提出了建设长江上游绿色生态屏障的生态对策和基本途径,即(1)对长江上游地区进行科学合理的生态功能划分,初步划分为6个生态功能区;(2)保护现有林,建立健全森林资源管理、监测和保护体系;(3)加强造林困难地带植被的保护,促进森林植被的恢复;(4)构建以生态效益为主,经济效益为辅的生态公益防护骨架体系,以提高植被覆盖率为最终目标;(5)增加现有人工林的生物多样性,提高森林生态系统的功能;(6)应着重对干热干旱河谷、高海拔生态脆弱区等困难地带植被恢复与重建树种选择与培育以及乡土树种和资源植物的选择与栽培等技术进行研究。

A comprehensive analysis was made of the ecological environment situations and their changes such as biodiversity, soil and water losses, natural calamity, water resource, soil degradation and agricultural environment in the upper reaches of the Changjiang River, and feasibility and necessity of establishing the green ecological protective screen were expounded in this paper. The existent questions and mistaken ideas were sufficiently discussed in suiting measures to local conditions, selecting of the native tree species, simplifying of plantations,protecting of existent forests and planning of afforestation, and also some basic ways or measures were put forward for solving problems in establishing the green ecological protective screen for the upper reaches of the Changjiang River.Namely,(1) the ecoregions in the upper reaches of the Changjiang River should be rationally divided, including 6 ecological function regions; (2) The existent forests should be well protected and the systems of management, monitoring and protection should be set up;(3) The protection of vegetations in difficultly planted zones should be strengthened and the forest vegetation restoration should be accelerated; (4) With the increasing percentage of vegetation, the framework system of the protection forest would be established; (5) Increasing the biodiversity of existent plantations aimed to enhance ecological function of forest ecosystems; (6) Priorities of research should be given to selecting and cultivating techniques of trees in difficultly planted zones such as the xerothermic or droughty river valleys, ecologically fragile zones with a high elevation, local tree species and resource plants.