Monterey Bay Aquarium Research Institute
Land/Ocean Biogeochemical Observatory in Elkhorn Slough

The Challenges of Biogeochemistry

Aquatic biogeochemistry combines traditional scientific fields (as the name implies) to investigate ecosystem-level fluxes of nutrients in marine and freshwater environments.

Nutrients are organic and inorganic forms of Carbon, Nitrogen, Phosphorus, and many other elements. Nutrient cycles are influenced by biological, geographical, geological, and chemical processes. For example, in coastal systems nitrogen is present as molecules that range from dissolved gases to complex biological proteins. Inputs of nitrogen include N2 fixation in the water column, and run-off from land. Export includes biochemical reactions in the sediment that release nitrogen gas and fishing or aquaculture that remove organic nitrogen.

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The biological and chemical components of most ecosystems are heavily dependent on each other. Nutrient loading can determine ecosystem structure by enhancing or reducing primary production. Primary production, in turn, is the main source of nutrients for all other organisms within the ecosystem. Species composition and growth rates of the primary producers can determine what organisms will thrive in the environment, and what ones will not survive. Many factors, such as temperature, precipitation, or geographic location each contribute to the dynamic structure of aquatic ecosystems by affecting nutrients, physical forces, or the organisms themselves.

Even relatively simple ecosystems are difficult to study because of the money and time required for scientific research. Coastal environments are both spatially and temporally dynamic, and therefore long term and carefully planned observations and experiments are the only was to make sense of the changing conditions. Not surprisingly, few studies are able to accomplish all of these tasks, and therefore researchers must make the best of their partial knowledge to characterize the biogeochemical cycles of a given study area.

The Potential of Sensor Networks

The benefits of long term deployment of instruments in the environment are being realized in many fields of science and engineering. The ability to access the data in real time, through satellite or wireless technology, is creating a new era of observational science. The LOBO project is such a network, and represents the first attempt to characterize the biogeochemical system of an aquatic environment on a high resolution scale. This is possible because of advances in chemical sensors that allow for in situ nutrient measurements.

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Land/Ocean Biogeochemical Observatory

Last updated: Feb. 06, 2009