雪灾对古田山常绿阔叶林建群种养分含量及归还量的影响

Effects of snow damage on the leaf litter’s nutrient content and return amount of constructive species in evergreen broadleaved forest in Gutianshan National Natural Reserve, East China

在古田山国家级自然保护区24hm2长期监测样地设置凋落物收集框,对常绿阔叶林的养分归还量进行动态监测。2008年初南方发生特大雪灾,为研究雪灾对建群种甜槠和木荷凋落叶中主要养分含量、归还量的影响提供了契机。结果表明:(1)虽然建群种凋落叶中碳含量受雪灾影响不显著,但雪灾导致其凋落量明显下降,因此碳的归还量在灾后明显减少。(2)建群种凋落叶氮含量在雪灾前后有显著差异,表现为灾前<灾后;但因受凋落量的影响,其归还量仍表现为灾前>灾后。(3)建群种凋落叶磷含量在雪灾前后存在极显著差异(P<0.01),表现为灾前<灾后,导致其归还量也表现为灾前<灾后。

A 24-hm2 plot was installed in the Gutianshan National Natural Reserve, East China to dynamically monitor the leaf litter＇ s nutrient content and return amount of evergreen broad- leaved forest. In 2008, a serious snow damage event happened in southern China, which gave us an opportunity to study the effects of snow damage on the leaf litter＇ s nutrient content and return amount of two constructive species （ Castanopsis eyrei and Schima superba） in the evergreen broa- dleaved forest. No obvious difference was observed in the leaf litter＇ s C content of the construc- tive species before and after the snow damage, but the leaf litter＇ s production after the snow damage damage showed an obvious decrease, and thus, the leaf litter＇ s C return amount after the snow also showed an obvious decrease. As compared with that before the snow damage, the leaf litter＇ s N content of the constructive species after the snow damage was significantly larger, but the litter＇ s N return amount was smaller, due to the decrease of the litter＇ s production after the snow damage. Same as the leaf litter＇ s N content, the leaf litter＇ s P content of the constrnc- tive species after the snow damage was significantly larger than that before the snow 0.01 ）, and the leaf litter＇ s P return amount also presented the same pattern. damage （ P〈