ABSTRACT
The ocean/land interface occupies about 8% of the earth’s surface (Ray & Hayden 1992) along 594000km of coastline (Hammond 1990). In this ecotone terrestrial and aquatic habitats interact intensively altering salinity, turbidity, nutrients and climatic regimens in coastal waters through freshwater runoffs on the one hand and affecting productivity of coastal areas through a large input of material from the adjacent aquatic systems on the other. The spatial boundaries are continuously crossed by the basic components of food webs. Ecologist are now more aware of how ecosystems are closely bound to one another and how factors outside a system may significantly affect or even dominate local patterns and dynamics. Polis et al. (1997) defined this exchange of organic matter between habitats “a spatial subsidy”, as
a donor-controlled resource (prey, detritus, nutrient) from one habitat to a recipient (plant or consumer) from a second habitat which increases population productivity of the recipient, potentially altering consumer resource dynamics in the recipient system.
