森林生态系统的水文调节功能及生态学机制研究进展

森林水文调节功能是森林所实现的重要服务功能之一,可是由于森林资源被无节制的开采利用,导致人们不断遭受森林破环所带来的洪旱灾害。因此关于森林生态水文功能研究已成为生态学和水文学的研究重点之一。近年来,国内外对森林水文调节过程及其生态学机制进行了广泛深入的研究,所以文章从森林的水文过程出发,对林冠截留、树干流、凋落物层截留、林地水分涵养和蒸发蒸腾及其影响因子的国内外研究现状进行了归纳分析,研究认为林地各冠层均能够截留降雨,降低雨水动能,从而减少地表径流的产生和对地表的冲击;凋落物层能蓄留水分、抑制蒸散、减缓地表径流;而树干流改变降雨水平空间格局,影响水分入渗以及土壤水源涵养。森林结构复杂,明显改变了降雨分配过程,而森林水文过程及调节功能又受到森林结构的制约,因此定量定性探讨森林生态系统的结构、过程与水文调节功能之间关系,是未来森林生态水文功能研究的重点。

Hydrological adjusting function of forest ecosystems and ecological mechanism: A review

Hydrological adjusting function of forests is one of the important functions in forest ecosystem services. At present, people have experienced great disasters that result from disruption of forest because we have exploited and disrupted forest excessly. There- fore, close attention is paid increasingly to ecohydrological functions of forests in ecology and hydrology. In recent years, hydrologi- cal adjusting function and ecological mechanism of forest ecosystems were studied widely and made great progress around the world. Therefore, from this aspect of hydrological processes of forests, a systematical review in this paper is made at home and abroad about the researches of the crown interception, the stem flow, litter absorption, soil-water conservation and evapotranspiration and these factors. Results showed that: Forest canopy intercepted rainfall, reduce kinetic energy of raindrop, so as to decrease the runoff amount and surface washout; the litter layer accumulated water, restrained evaporation and moderated runoff; stemflow altered the spatial pattern of rainfall below the canopy, influenced infiltrating water and conservation of water supply. Forest ecosystems, how- ever, had complicated lay structure and an impact on rainfall redistribution. Hydrological process and adjusting function of forests were restricted by forest structure. Consequently, qualitative and quantitative research on the relation among forest structure, process and hydrological adjusting function was the hot spot on ecohydrological function research of forest ecosystems in future.