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共对200个技术上可行的杉木栽培模式,以 NPV 最大为主要目标进行优化,确定出立地指数为14、16、18下的5种初植密度优化栽培模式。对初植密度、间伐次数、间伐时间、间伐间隔期、间伐强度及轮伐期等栽培措施,从土地生产率与劳动生产率的提高与平衡角度,进行实例优化分析。运用增量分析方法,研究不同栽培措施下,成本、价格、折现率等经济因素变化对栽培模式优化的影响规律。特别是对间伐量和间伐时间的交互作用,初植密度与间伐管理的交互作用,初植密度、间伐次数与轮伐期的交互作用进行了经济分析.并对用不同经济指标决定的最优轮伐期进行比较分析.
A total of 200 technically feasible Cunninghamia lanceolata cultivation models were optimized with the maximum NPV as the main objective, and five optimal planting density cultivation models with site indices of 14, 16 and 18 were identified. The planting density, the number of thinning, the thinning time, thinning interval, thinning intensity and rotation and other cultivation measures, from the land productivity and labor productivity improvement and balance point, the case optimization analysis. The incremental analysis method is used to study the influence of economic factors such as cost, price and discount rate on the optimization of cultivation modes under different cultivation measures. Especially the interaction between thinning and thinning time, the interaction between initial planting density and thinning management, the density of initial planting, the interaction between thinning number and rotation period, A comparative analysis of the rotation period.