亚热带常绿阔叶林和杉木人工林茎流与穿透雨的养分特征

亚热带常绿阔叶林和杉木人工林树干茎流和穿透雨养分含量均表现季节动态变化。养分含量中，K^ 、Ca^2 、NO3%-浓度高，Na^ 、Mg^2 居中，HPO4^2-含量低，相对于林外雨，养分均出现富集化，但树干茎流养分富集化高于穿透雨。树干茎流出现强烈的酸化，而穿透雨酸化现象不明显。树种之间的茎流养分特征表现不一样，樟树和枫香总的养分浓度较高，其次为刨花楠，最后为青冈和红栲。

Nutrient characteristics of stemflow and throughfall in evergreen broad-leaved forest and Cunninghamia lanceolata plantation forest

Concentrations of major nutrients in stemflow and throughfall in evergreen broad-leaved forest and Cunninghamia lanceolata plantation forest were analysed. The results showed that concentrations of the nutrients in both stemflow and throughfall changed seasonally. The nutrients were enriched in stemflow and throughfall, and the enrichment of nutrients in stemflow was higher than that in throughfall. Among all analsyed nutrients, the concentration was found highest for K+,Ca 2+ and NO 3- , middle for Na+ and Mg 2+, and lowest for HPO 4 2-. Compared with throughfall, stemflow was significantly acidified. In addition, the nutrient characteristics of stemflow for different tree species differed significantly. The total concentration of nutrients in stemflow was found highest in Cinnamomum camphora and Liquidambar formosana, middle in Machilus pauhoi, and lowest in Cyclobalanopsis glauca and Castanopsis hystrix.