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采用收获法测定安塞沙棘人工林不同林龄林分的地上部生物量 ,分析沙棘人工林发育过程中地上部生物量和净初级生产量的变化趋势 ,建立沙棘单株地上部各器官分量的回归模型。结果表明 :沙棘人工林 4～ 5a即可郁闭 ,郁闭度为 0 .8～ 0 .9。 1～ 8龄内 ,地上部生物量随林龄增加而增加 ,8～ 11龄增加缓慢 ,11～ 13龄趋于稳定 ,13龄的沙棘人工林地上部生物量为 115 1g m2 ,地上部生物量的器官分配为 :主茎 410g m2 (占 35 .6 % ) ,枝 478g m2 (占41.5 % ) ,叶 2 15g m2 (占 18.8% ) ,果 2 0g m2 (占 0 .0 2 % ) ,枯枝 2 8g m2 (占 0 .0 2 % )。 8龄沙棘人工林的净初级生产量为 6 0 0g (m2 ·a) ,此林龄后需采取林中间种油松 (PinustabulaeformisCarr.)、杨树 (Populussp .)等树种及牧草或平茬复壮等措施对林分进行改造
The harvesting method was used to determine the aboveground biomass of different age stands of Hippophae rhamnoides plantation. The changes of aboveground biomass and net primary production during the development of Hippophae rhamnoides plantation were analyzed. Regression model. The results showed that the seabuckthorn plantations could be closed from 4 to 5 years and the canopy density was from 0.8 to 0.9. From 1 to 8 years old, aboveground biomass increased with the increase of forest age, but increased slowly from 8 to 11 years old and stabilized from 11 to 13 years. The aboveground biomass of 13-year-old Hippophae rhamnoides plantation was 115 1 g m2, aboveground biomass (Accounting for 35.6%), branches 478g m2 (41.5%), leaves 2 15g m2 (18.8%), fruits 20g m2 (accounting for 0.02%), and dry Branch 2 8g m2 (accounting for 0 .0 2%). The net primary production of 8-year-old Hippophae rhamnoides plantations was 600 g · m-2. After this age, the species of Pinus tabulaeformis Carr., Populussp. And other measures to transform the forest