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我县地处杉木自然分布区的北缘,自七十年代开始大面积营造杉木林,现有面积14000余亩.因受立地条件及抚育管理水平的影响,各地杉木生长情况不太一致,经济效果也大不相同.本文以不同立地条件、不同营林管理水平下杉木生长情况,对其经济效益进行对比分析,以便对营造杉木,提高杉木生产的经济效益,提供数据.内容及方法我们于1983年5—11月间调查了本县顾陇、漆桥、青山、固城、薛城五个乡和大荆山林场的杉木林3215亩,这些林分除大荆山林场进行过间伐外,其余没有间伐过.调查设角规观测点315个,标准地12个(面积1亩)进行每术检尺,并测定4个样地近5年胸径生长量,观察土壤剖面12个,并将土层厚度超过80厘米,含石量少于15%,粘盘层下位的重、中壤土划为好的立地类型(Ⅰ);
My county is located in the northern margin of the natural distribution of Chinese fir, since the seventies large area to build fir forest, the existing area of more than 14000 acres.Because of the site conditions and the impact of tending and management, around the growth of fir is not consistent, the economy The effect is also very different.In this paper, under different site conditions, different management of fir plantation under the condition of its comparative analysis of economic benefits in order to create fir, fir economic benefits to improve production and provide data. Between May and November 1983, 3215 mu of Chinese fir forest were surveyed in Guolong, Qiaqiao, Aoyama, Gucheng, Xuecheng and Dashan Forest in the county from May to November 1983, except for the thinning of Jingshan Forest Farm , And the rest were not thinned.A survey of 315 angle gauges and 12 standard scales (1 acre area) were conducted for each ruler, and the diameter growth of 4 plots was measured for 5 years. 12 soil profiles were observed If the thickness of soil layer is more than 80cm and the content of stone is less than 15%, the soil type of heavy and medium loam under the sticky layer is a good site type (Ⅰ).