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目前对森林生态系统粗木质残体的研究主要着眼于数量动态、分布格局、分解速率以及对生物多样性保护的作用上 ,而对江河上游森林生态系统中粗木质残体的水文调蓄、缓洪滞淤等功能至今还未能引起足够的重视。CWD作为森林生态系统的重要部分 ,其水文生态功能的发挥主要是通过影响降水在林内的再分配以及林内微环境来实现的。森林CWD水文功能的发挥要同时受到外界环境和其本身持水性能的影响。CWD腐朽级的级别愈高 ,自然相对含水量愈高 ,而且愈容易吸水达到饱和。在长江上游亚高山暗针叶林生态系统中 ,自然状态下CWD可以蓄持约 7.41mm的降水 ,若使CWD全部达到饱和则可以蓄持降水达 9.91mm ,这意味着自然状态下的CWD的有效持水量可达到 2 .5 0mm ,无疑对于长江上游森林生态系统的蓄水调水、滞洪防蚀功能是一大贡献
At present, the research on coarse woody debris in forest ecosystem mainly focuses on quantity dynamics, distribution pattern, decomposition rate and its role in biodiversity conservation. However, hydrological regulation and control of coarse woody debris in the forest ecosystem in the upper reaches of the river Flood stagnation and other functions have not yet caused enough attention. As an important part of forest ecosystem, CWD plays an important role in hydro-ecological functions through affecting the redistribution of precipitation in the forest and the micro-environment in the forest. The CWD hydrological function of forest should be affected by both the external environment and its own water holding capacity. The higher the decay level of CWD, the higher the natural relative water content, and the easier it is for water to reach saturation. In the sub-alpine dark-coniferous forest ecosystem in the upper reaches of the Yangtze River, CWD can hold about 7.41 mm of precipitation under natural conditions, and can hold up to 9.91 mm of precipitation if all CWDs are saturated, which means that CWD The effective water holding capacity can reach 2.55mm, which is undoubtedly a great contribution to the function of water storage, water diversion and flood control and erosion prevention of the forest ecosystem in the upper reaches of the Yangtze River