Module 9: Marine Ecology

Ecology is a major component of oceanography. The ocean food chain begins with the primary producers who are responsible for producing the ocean's energy through photosynthesis and chemosynthesis. Phytoplankton are the ocean's main primary producers.

When consumers eat the producers (and each other) through different feeding relationships, they transfer energy through the ecosystem. As energy is produced and then consumed through the different trophic levels in the marine environment, there is at least a ninety percent energy loss at each level, which can be explained by the 2nd Law of Thermodynamics. The 2nd Law of Thermodynamics supports the idea that, due to disorder and inefficiencies in the process, energy deteriorates and is lost from a food chain over time. Food webs and energy pyramids are used by ecologists to pictorially demonstrate this concept.

Relationships in the ocean are extremely important. Many organisms rely on other organisms for protection or for survival through symbiotic relationships. These relationships can have benefits or consequences for the organisms involved in them, or they may be neutral. Predators and prey have a complicated relationship in that the population size of the prey dictates the number of predators that an environment can support.

Ecologists have their own set of terms and definitions to describe concepts, populations, and species. The world's diverse ecosystems provide homes to different types of marine communities. Each community has different characteristics and supports a different set of species.