采收方式对马尾松与黄藤间种林分经济效益的影响

Effect of Different Harvesting Regimes on Economic Benefit of Interplanting Daemonorops margaritae with Pinus massoniana plantation

收集黄藤试验地采收资料和马尾松标准地调查数据,评价13a经营期内5种采收方式对马尾松与黄藤间种林分经济效益的影响。结果表明:不同的初采年龄和采收间隔期对13a黄藤人工林经济效益具有重要的影响,其中7a初采和6a间隔期的采收方式获得最高的经济效益,净现值、内部收益率和收益成本比分别为18144元·hm-2、13.45%、1.32;黄藤间种后对19年生马尾松林分平均胸径、树高及株数产生不利影响,进而导致马尾松林分的纯收益和净现值比未间种时分别减少7500元·hm-2、3000元·hm-2;马尾松林分经济效益的减少可从间种黄藤所获得货币收入得到补偿,在5种采收方式下黄藤间种对整个林地产生的林地增益水平和净现值增量分别为3.07%～12.74%、514～2407元·hm-2。

Currently, with the rapid development of rattan plantations, the management technique and economic benefit have been gaining more and more concerns from both the government and private sectors. This study aimed to determine the impact of harvesting regimes on economic benefit of rattan plantation, to evaluate the effect of interplanting of rattan on the growth and yield of upper tree, and to analyze the economic return of rattan interplanting to the mixed stand. Permanent plots for harvesting Daemonorops margaritae were established in the mixed stand and 5 different harvesting regimes were set, including first harvesting at 5,6,7,8,9 years and harvesting intervals of 8,7,6,5,4 years respectively. In addition, field investigation on the upper support tree, 19-year-old Pinus massoniana mixed with D. margaritae was made and 2 plots nearby were also established in pure stand to know the effect of rattan planting on the growth and yield of support trees. Harvesting regimes had eminent effect on economics of 13-year-old D. margaritae plantation. Under the regime of first harvesting at 9 years with 4 years＇ interval afterward, optimal economic benefit was gained in D. margaritae plantation, being 18 144 yuan·hm^-2, 13.45% , 1.32 in term of net present value （NPV）, internal return rate （IRR） and the ratio of benefit to cost （B/C）. The interplanting of D. margaritae had unfavorable effect on the mean diameter, tree height and tree number of Pinus massoniana stand. As a result, the net income and NPV from P. massoniana plantation interplanted with D. margaritae decreased by 7 500 yuan·hm^-2and 3 000 yuan·hm^-2 respectively over those from pure stand. However, the economic loss in the upper stand could be compensated with the monetary gain from rattan plantation generating considerable economic benefit. The level of economic gain and the increment of NPV by interplanting D. margaritae with P. massoniana under various harvesting regimes were estimated to range from 3.07% to 12.74% and from 514 yuan·hm^-2to 2 407 yuan·hm^-2 .