检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:陈章水[1]
机构地区:[1]中国林业科学研究院林业研究所
出 处:《林业科学研究》1989年第1期78-83,共6页Forest Research
摘 要:据不完全统计,杨树人工林全国共有114.8万ha,为能进一步提高杨树经营管理水平,编制杨树二元立木材积表已成为当务之急。作者利用从1981年起经过5a时间测定与收集16个树种共6383株实测样木资料,编制了12个杨树二元立木材积表,供生产、科研工作应用。Practical measurement of 6 383 collected poplar cores from all of the poplar cultural areas in China has been conducted. After analysis of breast-height form-factor of various poplar stocks, the author divided them into 12 tree species groups. After the calculation of volume variation coefficient of each poplar tree species group, according to the equation n= t2C2/E2 the author analysed the required number of cores necessary for the establishment of volume tables and tried to establish them with 5 regression equations,then applying the residual standard deviation, coefficient of correlation and systemic deviation to test them and select the most suitable equation to establish the binomial stock volume table of Populus tomentosa, P.X canadensis, P. beijingensis, P. nigra, I-72/58,I-69/55, I-63/51, P. X euramericana Guinier cv. 'Sacrau', P.X euramericana Guinier cv. 'Robusta',P. taiging, P. X xiaozhuanica, P. purdomii, P. alba and P. alba var. pyramidalis. These tables have widely been used with good results.
分 类 号:S758.3[农业科学—森林经理学]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.222