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我省是全国唯一包含东部季风区、西北干旱区、青藏高原区三大自然区的省份。干旱少雨,地貌复杂,山地和高原占国土面积的70%以上。全省年均降水量约400毫米,其中占全省面积一半以上的河西地区年均降水量不足200毫米,严重影响营造林成效。随着林业建设的逐步深入,林业生态治理项目不断向远山、深山、沙区推进,自然条件越来越差,造林难度越来越大,生态恢复周期越来越长,治理成本越来越高,森林覆
The province is the only province that contains the three monsoon areas in the east, the arid northwest and the three natural areas in the Qinghai-Tibet Plateau. Drought and dry, complex landscape, mountains and plateaus account for more than 70% of the land area. The average annual precipitation in the province is about 400 mm, of which the annual average precipitation in Hexi area accounting for more than half of the province’s area is less than 200 mm, seriously affecting the effectiveness of afforestation. With the gradual deepening of forestry construction, forestry ecological management projects continue to advance to remote mountains, mountains and desert areas, with worsening natural conditions, more and more difficult afforestation, longer and longer ecological recovery cycles, and increasingly more and more cost High, forest cover