An aquatic ecosystem is an ecosystem takes place in a body of water, which has a community of organisms that depend upon each other to live and function. Three major ecosystem functions are energy flow, nutrient cycling, and biodiversity. Energy flows through an ecosystem and trophic levels from primary producers, which use solar energy in photosynthesis to synthesize complex organic substances (Reece & Campbell 2011, Lindeman 1942, & Gaston 2000). Solar energy is the basis from which all life in an ecosystem depend upon (Lindeman 1942). Nutrient cycling is passed from trophic level to trophic level and from ecosystem to ecosystem via consumption, translocation, fecal matter, and decomposition (Reece & Campbell 2011, Vanni 2002, & Hammer & Holmlund 1999). The nutrients often undergo many transformations from one chemical form to another (Vanni 2002). Ecologist Camille Parmesan explains the importance of biodiversity in an ecosystem and its benefits, such as breathable air being the result of plants and microorganisms (Reece & Campbell 2011). How efficient an ecosystem processes depends on the species present (Giller et al 2004). Energy flow, nutrient cycling, and biodiversity each a play a critical role in the regulation of ecosystems. In the sections to follow I will discuss each of these in depth.
Energy flows through an ecosystem and trophic levels from primary producers, which use solar energy in photosynthesis to synthesize complex organic substances (Reece & Campbell 2011, Lindeman 1942, & Gaston 2000). As energy flows through an ecosystem it goes in the form of primary productivity (a bottom up approach): nutrients are taken up by plants (primary producers); the plants are then eaten by primary consumers, which are devoured by secondary consumers; and finally secondary consumers are consumed by tertiary consumers (Reece & Campbell 2011, & Lindeman 1942). Detritivores, or also known as decomposers and as saprophagous organisms, feed on feces and decomposed matter, can act as an energy source for higher level consumers like secondary and tertiary consumers (Reece & Campbell 2011, & Lindeman 1942). The combined actions of animals – consumption of nutrients, defecation, and decomposing – and bacterial decomposers transform the potential energy of organic substances that plants release during catabolic processes, into an organic state, from which plants use the nutrients to resynthesize complex organic substances, thus finishing the cycle (Lindeman 1942).
Some of the most important processes that take place in natural ecosystems include conversion of energy into biomass, storage and allocation of minerals and energy in food chains, biogeochemical cycles, alteration of organic matter in soil and sediment, and climate regulation, which are controlled by abiotic factor interactions with living organisms through development and control mechanism (Vanni 2002, Groot et al 2002, & Gaston 2000). Different stages in life...