复测角规样本估计蓄积生长量的新方法

角规是一种效率高的测树方法。但用常规角规方法测林分蓄积生长量,在前后两期计数木相同的情况下,断面积生长量为0;如前后期计数木不同,则每相差一株计数木,对单位面积断面积和蓄积的生长量影响颇大。这种跳跃式变化往往不符合林分生长实际,从而影响这一方法的推广采用。为此,曾提出过许多其他用角规测林分蓄积生长量的方法。这些方法可概括分为两类。一类是直接方法,其前后两期都计数的保留木对林分蓄积生长量贡献很小,其断面积生长量为0,蓄积生长仅是形高生长。保留木断面积生长量

A NEW METHOD OF VOLUME GROWTH ESTIMATION FOR REMEASURED HORIZONTAL POINT SAMPLING

A new angle-count method for estimating the increment of stand growing stock has been proposed based on the angle subtended by the sample tree in this paper. As compared with other angle-count method, it has several advantages, for instance, smaller variance, higher relative efficiency, and convenient for continuous checks etc. The result tested by the data of continuous checks and measurements in Guangxi CFI has proved the advantages of the theoretical analysis of this method.