Marine benthic productivity

Abstract

Primary productivity is the production of energy and biomass through the process of photosynthesis. In marine ecosystems, the major primary producers are algae, from phytoplankton in the open oceans to algal forests in shallow coastal waters. Primary production underpins all marine ecosystems because the growth of primary producers supplies the energy that supports entire food webs. The amount of this productivity that enters these ecosystems is largely determined by environmental conditions such as light and temperature, and resource availability such as carbon dioxide and nutrients. The relative dominance of different species often varies as a function of abiotic conditions, with some species being more common through greater net productivity. When abiotic conditions change from their long-term average conditions, primary productivity and growth among the alternate species of primary producers can also change, potentially leading to a shift in the dominant species. Such “phase-shifts” often lead to substantial changes in the productivity and species diversity of a system.