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一 現有天然林的分布黄河流域森林很少,除去低价值的灌木叢林外,森林面積,初步統計約占流域总面積的百分之二。 1 黃河上游(龍羊峽以上,面積約124000平方公里)同德、拉加寺以上僅在河谷坡地散生着成叢的檜柏。拉加寺以下到貴德也没有大面積的森林,僅僅塊狀的分布着老令云杉和檜柏天然林,樹高不过20米。在兴海附近有一片森林,但面積不大,林木生長的也不好,每公頃的蓄積量約26.8立米。主要樹种也
The Distribution of Existing Natural Forests There are few forests in the Yellow River Basin. Apart from the low-value shrubbery, the forest area and preliminary statistics account for about 2% of the total basin area. 1 The upper reaches of the Yellow River (above Longyangxia, an area of about 124,000 square kilometers) Tongde, Raga Temple above only in the valley slopes scattered clumps of cypress. There is no large area of forest below Lajia Temple to Guide, with only the old block of spruce and juniper cypress forest, but the height is 20 meters. There is a forest near Xinghai, but the area is not big, and the trees are not growing well. The stock volume per hectare is about 26.8 cubic meters. The main species also