森林与生态环境(下)

Forest and Ecological Environment

生态环境的恶化已经成为当前国际社会最为关心和最迫切需要解决的问题。本文详细地阐述了森林与水土流失、土壤沙漠化、土壤退化、大气污染和酸沉降、噪声污染之间的关系,并认为应该发展森林来改善人类的生存环境。

Deterioration of ecological environment has become a problem of deepest concernto the international community, demanding an immediate remedy. This paper gives a de-tailed description of the relation between forests and soil, water erosion, land desertifica-tion, soil degradation, atmosphere polution, acid precipitation and noise polution. The area ofsoil and water erosion in the world has reached 2.5 billion ha. The total annual soil erosionammounts to more than 60 billion t. The land area threatened by desertifieation is 4. 5billion ha. and the population facing such a threat is 600～770 million. In 1991, the incomereduction resulting from the desert expansion is 42.3 billion US dollars. Tree planting andgrass growing is an important measure to check desertification. UN adviates the utilization ofa microbial process (photoautotrophic organism and azotobacteria) and biological measures(tree planting and grass growing) to modify the deserts, and has achieved better results inpractice. The soil degradation process always is: land denudation by destruction of forests andgrasses -- unreasonable utilization of the farm land -- decline of soil fertility -- land lyingwaste. Farm forestry is an effective measure to check the soil degradation. In the plains ofthree large river valleys integrated management measures (paddy raising, fish farming, reedgrowing and tree planting)are adopted to modify marshes, with better results obtained. Adiscussion is made on the uptake of air polutes and noise growing by forests.