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我场地处渭北黄土高原丘陵沟壑区,属于关山支脉,海拔690～1490米,土壤为碳酸盐褐色土,全年无霜期120天,年降雨量571毫米,年平均气温11.1℃,年最低气温(元月份)-17℃左右。我场建于1958年,现已营造刺槐人工林7.2万多亩,其中已郁闭成林的2.5万多亩,木材蓄积量达7.5万多立方米。从1971年起,抚育采伐2500多亩,生产小径级材800多立方米。为了摸素刺槐人工林生长规律及抚育采代有关问题,几年来,我们设计标准地进行了观察试验,现将初步观察情况报告如下。
My field is located in the hilly and gully region of the Loess Plateau in Weibei. It belongs to the branch of Guanshan Mountains and has an elevation of 690-1490 meters. The soil is carbonate brown soil. The annual frost-free period is 120 days. The annual rainfall is 571 mm, the annual average temperature is 11.1 ℃ and the annual minimum temperature (January) -17 ℃ or so. My field was built in 1958, has now created more than 72,000 acres of acacia plantation, of which 25,000 acres have been closed forest, timber volume reached 75,000 cubic meters. Since 1971, 2500 acres have been nurtured and cut to produce more than 800 cubic meters of footpath material. In order to simulate the growth of Robinia pseudoacacia plantation law and tending mining related issues, the past few years, we designed the standard observation test, the preliminary observations are as follows.