片断化森林的边缘效应与自然保护区的设计管理

Edge effects in fragmented forests:Implications for design and management of natural reserves

森林片断化引起了森林边缘物理环境与生物的变化。从森林边缘向林内,光辐射、温度、湿度、风等因素发生改变,这些反过来对边缘上和边缘附近的生物产生极其重要的影响。有些研究表明,生物与非生物存在明显的边缘-核心的变化梯度,而有些则没有。除了影响边缘效应的客观因素(如边缘的取向、地势、年龄等)外,主观因素对边缘效应也有影响。边缘对生物与非生物的影响因片断化森林的面积、形状以及与其他森林片断连接程度的不同而不同,故边缘效应的研究对自然保护区的设计管理有一定的指导意义。

Forest fragmentation causes large changes of the physical environment as well as biotic changes in forest edges.As a result,environmental factors such as fluxes of radiation,air temperature,air moisture,soil moisture and wind,vary between the edge and interior in some forest fragments.These in turn can have important influences on the biota at or near the edge.Some research results show significant gradient trends from the edge to the core of fragmentation,while others do not. The orientation,physiongnomy and age of forest edges all affect the results;while the subjective reason should not be neglected.The influences of edges on biota and abiota are modified by the size,shape of forest fragments,and the connectivity with other fragments.The study on edge effects of forest fragments is of great significance in the design and management of natural reserves.