论文部分内容阅读
本文通过对落叶松枯梢病不同病情与林木材积生长损失关系的研究结果， 建立不同新梢发病率与每公顷立木材积生长损失量的回归关系式为： ｙ＝ ２．９２７８／１＋ ｅ６．６１９６－ ０．１７４９ｘ。在此基础上， 根据当前生产防治效果和立木林价， 计算不同防治效果时的防治效益， 采用经济阈值法， 计算防治指标。制定出不同防治成本和防治效果时的防治指标查定表。以相对误差限法确定该病的为害指标为新梢发病率１５。
In this paper, the relationship between different disease conditions of Larch Blossoms and the growth of timber volume was studied. The regression equation was established as follows: y = 2.9278 / 1 + e6.6196 - 0.1749x. On this basis, according to the current production control effect and standing tree forest price, the prevention and control benefit when different control effects are calculated, the economic threshold method is used to calculate the prevention and control index. Formulation of different prevention and control costs and prevention and control of indicators checklist. The relative error of the law to determine the disease damage index for the incidence of shoots 15 .