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甘孜藏族自治州位于四川西部,地势从最高一级的青藏高原向第二级云贵高原和四川盆地的过渡地带,平均海拔3500m,最高达7500m,境内山高谷低,地形复杂多样。气候属青藏高原大陆性气候,特点是冬长无夏,雨量少且分布不均,干湿季明显,气温日较差大,生长期仅130—180天,为林业生产带来很多不利因素,森林一旦遭到破坏就很难恢复。更新成效低,树木生长缓慢。境内主要河流有金沙江,雅砻江、大渡河及其密布的大小支流,有137万公顷森林分布在这些河流的中上游,其水土保持和水源涵养的作用十分重要。全州总面积15万平方公里,其中有林地面积137万公顷,森林复盖率仅9.4％,且分布不均,灌
Ganzi Tibetan Autonomous Prefecture is located in the western part of Sichuan. Its terrain ranges from the highest level of Qinghai-Tibet Plateau to the second-level of Yunnan-Guizhou Plateau and the transition zone of Sichuan Basin with an average elevation of 3,500m and a maximum of 7,500m. The territory has a high valley and a complex topography. The climate belongs to the continental climate of the Qinghai-Tibet Plateau. Its characteristics are that the winter is long and without summer, the rainfall is less and unevenly distributed, the wet and dry season is obvious, the temperature day is bad and the growth period is only 130-180 days, which brings many unfavorable factors for forestry production. It is hard to recover once the forest is damaged. The update is ineffective and the trees grow slowly. The major rivers in the country include the Jinsha River, Yalong River and Dadu River and their densely populated tributaries. About 1.37 million hectares of forest are distributed in the upper and middle reaches of these rivers, and the role of soil and water conservation and water conservation is very important. The state’s total area of 150,000 square kilometers, of which 1.37 million hectares of forest area, the forest coverage rate of only 9.4%, and uneven distribution of irrigation