马尾松直径生长与气侯的非线性响应函数

NONLINEAR RESPONSE FUNCTION OF GROWTH OF PINUS MASSONIANA TO CLIMATE

在Ｆｒｉｔｔｓ响应函数基础上，提出一种树木生长对各气候变量的非线性响应函数。该响应函数把气候变量的交互作用（各气候变量乘积）之和进行合并，不仅防止了自由度的显著下降，而且还有助于了解各气候变量交互作用对树木生长的平均效应。一组马尾松芯样（１５株树，３０个芯样，位于马尾松分布带北端）经定年和除趋势后得到的年轮年表与各月平均气温、降水量的关系，经该非线性响应函数分析，表明所取马尾松对前１年１１月、当年２、５、８、９、１１月的降水量的平方有显著正响应；对前１年１２月、当年３、８、１２月的平均气温之平方有显著正响应，而对当年２月的平均气温的平方有显著负响应。

A nonlinear response function of tree growth to climate variables was developed under the Fritts' response function, and the cross products of the variables were combined into one item through which it not only avoided the significant loss of degree of freedom but also helped to learn the average cross effect of the climate variables on the growth.A group of cores(15trees, 30 cores) of Pinus Massoniana which is near its northern distribution limit were dated, and the trends of ring width were deleted, then the obtained chronology and standardized average monthly temperature and monthly precipitation were analyzed by the nonlinear response function. The results showed that the response of the growth was significantly positive to the squares of temperature of December of prior 1 year, March, August and December, and to the squares of precipitation of November of prior 1 year,February, May, August, September and November, but the response was significantly negative to the square of February average temperature. The results could be explained by other's studies on this species.