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
机构地区:[1]西北林学院森林资源保护系
出 处:《西北林学院学报》1990年第1期75-81,共7页Journal of Northwest Forestry University
摘 要:安康、汉中地区栎林面积91.67万ha,蓄积5102万m^3,占整个有林地面积、蓄积的40~50%。在陕南生态平衡、工农业生产中起着极为重要的作用。现有栎林分布不均,可利用性差,中、幼龄林分比重大,质量不高,生产力低;连续多年超伐,森林蓄积大幅度减少。应采取果断措施,制止当前在栎林资源利用中的失控行为,压缩对栎林的消耗;大力造林和改造次生林,扩大栎林资源面积,提高林分质量;节约资源提高资源利用效益,从根本上缓解栎林供需矛盾。Describes the present status of oak forest of in Ankang and Hanzhong districts Shaanxi Province and improvement measures suggested. The oak forest covers an area of 0.9167 million hectare and a volume reserve of 51.02 million m3. But it is unevenly distributed and the availability is low. Young growth oak occupy a larger area than other age-grade oak forest, but the grade is poor, and the productivity is low. Overcutting deteriorates the oak forest severely in recent years. Thus every effort should be taken to control the destructive cutting and management measures should be practised to improve the quality of forest and relax the contradiction of supply and demend of oak forest resource.
分 类 号:S792.180.6[农业科学—林木遗传育种]
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:216.73.216.31