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机构地区:[1]定西市华家岭林业站,甘肃通渭743305 [2]甘肃农业大学林学院,甘肃兰州730070
出 处:《甘肃林业科技》2013年第1期13-16,共4页Journal of Gansu Forestry Science and Technology
基 金:甘肃省高等学校研究生导师科研项目"黄土丘陵区低效公益林改造技术及生态风险评价(1202-01)"
摘 要:通过小班调查和数据分析,得出华家岭防护林带的树种结构中,杨树占85.54%、云杉占10.02%、油松占4.18%、柳树占0.92%,其中胸径在10 cm以下的杨树和云杉分别占到了各自比例的一半以上;区域内的杨树林以近熟林为主,云杉林则以幼龄林为主;郁闭度在0.20~0.39的有林地的面积、蓄积分别占到了林地总面积、蓄积的95%以上。调查表明,当地杨树林带的生长状况较差,形成了大量的低产低效林分。因此,应对杨树残败林进行抚育、修复,在树冠下定植云杉、油松、侧柏、沙棘、柠条等树种,以不断改善和逐步优化树种及林分结构。Based on sublot investigation and data analysis, it showed that the proportion of Populus hopeiensis is 85.54%, Picea asperata is 10.02%, Pinus tabulaeformis is 4.18%, and Salix matsudana is 0.92% at Huajialing shel- terbelt. The proportions of DBH (diameter at breast height) of P. hopeiensis and P. asperata, which is less than 10 cm, were respectively more than 50%. The development stage of P. hopeiensis is near to the mature forest and P. asperata is mainly on the stage of young forest. The forest land area and the stand volume, which canopy densityis from 0.20 to 0.39, are accounted for more than 95% of total forest area and Volume. The investigation showed that the growth-de- velopment status of P. hopeiensis was poor, mainly of it are on low level of production and efficiency. Facing to these, the following measures can be taken to improve and optimize the structure of tree species and the stand structure, such as cultivating and repairing in the deteriorated wood of P. hopeiensis, and planting Picea asperata, Pinus tabulae- formis, Platycladus orientalis, Hippophae rhamnoides, it. korshinskii and other species under the canopy of
分 类 号:S757.53[农业科学—森林经理学]
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