采用随机区组设计对巨尾桉植苗林与萌芽林进行研究.结果表明:4~6 a龄植苗林保存密度、出材量及造林、采运、销售成本均大于萌芽林,而树高、胸径、单株蓄积、利润、年均利润及净现值小于萌芽林,两种更新方式林木的年均利润、净现值均先增大后减小,峰值出现在第5年,分别达7299.1元·hm-2·a-1、18166.5元·hm-2和7139.4元·hm-2·a-1、16073.4元·hm-2;6 a龄后植苗林连年生长量及经济效益逐渐大于萌芽林,且植苗林年均利润及净现值逐渐趋于平稳增长,而萌芽林生长后劲不足,其最佳主伐时间为5 a.%In this study planted and coppice plantation stands of Eucalyptus grandis × E. urophylla were compared, using a randomized block design field trial. Stand density, timber outturn, cost of afforestation, harvesting and log transportation and sale values of planted stands were greater than those of coppice stands at ages of 4 to 6 years. However, the tree heights, DBHs, individual stem volumes, profit, average annual profit and net present values were less for planted stands than those of coppice stands. Average annual profits and net present values of both types of stands increased with stand age but then later started to decrease, with peak values occurring at age 5 years. For coppice stands, the peak values of these two economic indicators amounted to 7299.1 RMB·hm-2·a-1 and 18166.5 RMB·hm-2 respectively, and for planted stands they were 7139.4 RMB·hm-2·a-1 and 16073.4 RMB·hm-2 respectively. The current annual increment and economic benefits of planted stands started to surpass those of coppice stands beyond age 6 years with average annual profits and net present values showing greater increases beyond this age whilst the increases in these indicators for coppice stands tended to decline, with the optimal rotation age for the latter stands being around 5 years.
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