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我场位于河曲县中部,属于黄土丘陵沟壑区。平均海拔1300米,年平均气温8.8℃,年降雨量平均400毫米左右,且分布不匀,主要集中在7、8、9三个月,无霜期130—140天,土壤为干瘠的沙壤土,有机质含量0.5%以下,植被主要有铁杆蒿、沙蓬、白茅等耐旱植物。自1960年建场以来,造林78,000亩,保存面积为56,402亩。经1979年10月森林资源清查,生长较好的林分为9,932亩,平均每亩蓄积量0.76立方米,可见,即使生长最好的林分,产量也很低。更为严重的是早期营造的杨树近2万亩,已形成慢生低产的“小
My field is located in the middle of Hequ County, belonging to loess hilly and gully areas. The average elevation of 1300 meters, the annual average temperature of 8.8 ℃, the average annual rainfall of about 400 mm, and unevenly distributed, mainly concentrated in 7,8,9 three months, frost-free period 130-140 days, the soil is dry barren sandy loam, organic matter Content below 0.5%, the main vegetation Artemisia Artemisia, Sabotown, Imperata such as drought-tolerant plants. Since it was established in 1960, 78,000 mu of afforestation area has been preserved with an area of 56,402 mu. After the inventory of forest resources in October 1979, 9,932 mu of well-planted forest grew with an average volume of 0.76 cubic meters per mu. As a result, the yield was very low even for the best-growing stands. Even more serious is the early creation of almost 2 million mu of poplar, has formed a slow slow production of "small