Food Web Linkage between Forest and Stream Ecosystems: Evaluation by Large-scale Field Manipulation Experiment

点击翻译按钮获取中文摘要

The matter flows across a forest-stream interface can have significant influences on food web dynamics by altering the species interactions in both forest and stream ecosystems. Manipulative field experiments clearly shown the energy flow between these systems support the abundance and diversity of variety of consumers in recipient systems. Allochthonous resources not only support the basis for consumer production but also alter trophic interactions in recipient communities in multiple ways. The subsidized consumers can both negatively and positively affect the in situ prey populations. It is suggested that foraging behavior and resource quality and quantity are crucial determinants of indirect effects of allochthonous resource inputs on in situ prey populations. Furthermore, it is suggested that seasonally fluctuating subsidy can stabilize the dynamics of the recipient food web. The food web stability of recipient system is greatly enhanced by seasonal subsidies that concentrate the t … More ime when the in situ productivity is low. The offset of the peak of productivity in juxtaposed systems is important in stabilizing the food web dynamics.The importance of understanding such ecological functions produced by habitat linkages is growing because human interference is rapidly altering the spatial patterns of habitat interfaces on a broad scale. Well-developed overhanging vegetation in a riparian forest, for instance, can enhance the input of terrestrial invertebrates. Furthermore, meandering and/or braided stream channels can be expected to increase the supply of emerging aquatic insects per unit area of forest. This report shows that stream geomorphology can exert powerful, possibly even dominant, influences over adjacent riparian bird communities in seasonally fluctuating landscape. The importance of organismal attribute as a factor regulating the matter flow between systems were also shown. These findings strongly suggested a synergistic effect of physical and biological attributes on matter flow between systems on food web dynamics in recipient system. The importance of reciprocal resource subsidies between habitats indicates that the loss or degradation of one habitat may have more detrimental effects on neighboring communities than we have previously recognized. Less