热带季节雨林近地层CO_2堆积的气象条件分析

An Analysis of Meteorological Conditions Causing CO_2 Pooling in the Surface Layer in a Tropical Seasonal Rain Forest,SW China

热带雨林内CO2浓度分布随近地层CO2堆积现象的出现而发生显著变化,对估算林内各层植被冠层CO2储存项有直接影响.通过寻找形成近地层CO2堆积的主要气象控制因子,有助于判别不同气象条件在近地层CO2堆积中的作用.采用基于因子分析的主成分提取方法,将8个气象因子观测资料整合为3个主成分,并逐一揭示4个典型时期各主成分的支配因子在近地层CO2堆积形成中的作用.结果表明:热量条件是影响11—12月(雾凉季)、3—4月(干热季)、9—10月(雨季后期)近地层CO2堆积的主要气象条件.水分条件是6—7月(雨季前期)近地层CO2堆积的主要气象条件.动力条件对近地层CO2堆积影响较弱,仅起到辅助作用.

The concentration of CO2 in tropical rain forests is significantly affected by the CO2 pooling near ground layer. The CO2 pooling may directly influence the estimation of carbon storage at different canopy layers, especially the inner canopy（ below the 33.5m above ground layer）. To differentiate the effect of different weather conditions on CO2 pooling near the ground layer, weather factors near the ground layer were collected and analyzed in a tropical seasonal rainforest. By using principal components extraction method, eight meteorological factors were integrated into three principal components and the contributions of each principal component to the forming of CO2 pooling near the ground layer were analyzed in four different time scales. Results show that heat conditions play an important role in Nov-Dec （fog-cool）, Mar-Apr（ dry- hot） and Sep-Oct （later rainy season ）, while water condition is more important in Jun-Jul （previous rainy season）on the forming of CO2 pooling near the ground layer. Dynamic condition shows relatively weak influence which only plays a supplementary role in different time scales.