环境因素影响草地柠条生长的主成分及典型相关分析

Principal Component and Canonical Correlation Analysis of the Environmental Factors Influencing the Growth of Caragana korshinskii Kom. in Grassland

为探讨柠条灌木林与各影响因素在生态恢复过程中的相互作用,并为柠条灌木林资源的合理开发利用提供理论依据,利用1985-2007年观测资料,选取18个指标,分别代表生长因子、气候因子、地形因子和土壤水分因子,基于主成分分析和典型相关分析,对宁夏固原河川上黄东山草地柠条林的生长过程进行了研究。结果表明:影响草地柠条生长的诸因子经主成分分析后可得5个主成分;其中气候因子、地形因子影响生长因子和土壤水分因子,同时生长因子又受土壤水分因子的制约。不同因子指标集团的典型相关分析表明,气候因子的积温、蒸发量影响地径和生物量,SW1、SW2、SW3、SW4、SW5和SW6受坡位、海拔、积温和蒸发量的共同影响,而生物量、株高和冠幅主要受SW2、SW3、SW4、SW6的影响。

The growth process of Caragana korshinski Kom. was studied in Dong mountain grassland at Shanghuang Hechuan of Guyuan, NingXia Hui Autonomous Region based on the observation data from 1985 to 2007 using principal component and canonical correlation analysis on 18 indices which were chosen to represent growth factors, climatic factors, terrain factors, and soil moisture factors. The results show that 5 principal components were obtained by principal component analysis, among which the climatic and terrain factors influenced the growth and soil moisture factors, and growth factors were restricted by soil moisture factors. The canonical correlation analysis indicate the relationships of four indices （growth, cli- matic, terrain, and soil moisture factors） were as follows： accumulated temperature and evaporation influ- enced ground diameter and biomass; SW1, SW2, SW3, SW4, SW5, and SW6 were jointly i slope position, altitude, accumulated temperature, and evaporation; biomass, plant height width were mainly influenced by SW2, SW3, SW4, and SW6.