【摘要】 马尾松林、针阔叶混交林和季风常绿阔叶林是南亚热带鼎湖山地区由演替初期到成熟森林过程的典型代表,对3种林地的降雨量及其再分配过程进行观测,并测定该过程中养分(N、P、K、Ca、Mg)浓度。结果表明,大气降雨经过冠层再分配后,除Ca外,各养分浓度在穿透雨和树干流中都有所增加,树干流增加的幅度更大。穿透雨中Ca元素浓度低于大气降水,这一现象在3种林型均有表现。穿透雨和树干流中养分浓度在演替系列上没有显示出一致的规律,但比较不同演替阶段的输入量可以看出,树干流养分输入量随演替进行呈增加趋势。经过冠层作用后,雨水带来的养分输入量大于凋落物分解输入量,这种现象在马尾松林和混交林尤为明显。表明大气降雨不仅促使养分元素从冠层向地表迁移,而且提供了演替初期植物生长所需的重要养分。更多还原

【Abstract】 Pinus massoniana forest,mixed P. massonniana-broadleaved forest,and monsoon broadleaved evergreen forest are the three typical subtropical forests at the succession stages from pioneer community to nearly climax in Dinghushan Nature Reserve in South China. In this paper,the differential patterns of five nutrient elements (K,Ca,Mg,N,and P) in rainfall and its redistribution in these forests were studied. The results showed that after the redistribution of rainfall through canopy,the concentrations of test nutrient elements except Ca in throughfall and stemflow had somewhat increase,especially in stemflow. In all the three forests,the Ca concentration in throughfall was lower than that in rainfall. The nutrient concentrations in throughfall and stemflow didn’t show any significant changes in these forests,but the nutrient inputs in stemflow had an increasing trend with the progress of succession. In addition,the nutrient inputs of throughfall and stemflow were generally higher than those of litter fall,especially in the mixed forest and P. massoniana forest. Our results suggested that rainfall not only played an important role in nutrient transfer from forest canopy to soil,but also supplied necessary nutrients for forest growth,especially for that at early succession stage.更多还原