不同生长阶段马尾松生产力与气候因子的关系

Pinus massoniana productivity at different age stages in relation to climatic factors

林木生产力的大小与气候密切相关,掌握不同年龄阶段林木生产力与气候因子的关系对生产力预测及森林经营具有重要意义。本文利用1964—2011年温度、降水、相对湿度、日照时数等气象资料,结合气候湿润指数,运用树干解析数据,定量研究了马尾松生产力与气候因子的关系。结果表明:影响幼龄阶段、中龄阶段和近熟阶段马尾松单木生产力的气候因子各不相同,幼龄时期的单木生产力与3月相对湿度和1月的气候湿润状况显著相关;中龄阶段马尾松生长的限制因子为10月、7月高温和9月的日照时数,7月和5月的湿润状况对其生产力也有显著影响;近熟阶段马尾松生产力的大小与7月的降水量和湿润状况呈极显著正相关(P<0.001)。研究区域湿润温暖的气候基本满足了马尾松生长对水分和热量的要求,但生长中期的高温少雨限制了中龄阶段和近熟阶段马尾松单木生产力的增长。

The productivity of forest trees has close relationships with climate. Understanding the relationships between forest tree productivity at different age stages and climate factors is of signif- icance in the productivity prediction and forest management. By using the meteorological data （ including mean monthly and annual air temperature, mean relative moisture, total precipitation, and total sunshine duration） in 1964-2011, and in combining with climate moisture index, this paper quantitatively evaluated the relationships between Pinus massoniana productivity at different age stages and climate factors. The P. rm^soniana productivity in the last 47 years was calculat- ed based on the relationships between tree biomass and diameter at breast height （DBH）. Analy- sis of covariance, partial correlation, and stepwise multiple regression analysis were adopted to identify the effects of climate factors on the P. massoniana productivity. The results showed that the effects of climatic factors on the P. massoniana productivity differed with tree age. The pro- ductivity of young trees was significantly affected by the relative humidity in March and the cli- mate moist condition in January; the productivity of middle-aged trees was significantly affected by the high air temperature in July and October, the sunshine duration in September, and the cli- mate moist condition in July and May ; whereas the productivity of premature trees showed signifi- cantly positive responses to the precipitation and climate moist condition in July. The warm and humid climate was favorable for the growth of P. massoniana, but precipitation limited the productivity of middle-aged and premature the high temperature and low trees.