Marine Biodiversity

What is marine biodiversity?

Biodiversity is an all-inclusive term to describe the total variation among living organisms of our planet. In its most simple form, biodiversity or biological diversity is therefore 'Life on Earth' and marine biodiversity is 'Life in the Seas and Oceans.` The marine environment has high diversity because 32 out of the 33 described animal phyla are represented in the marine environment.

Biodiversity includes four main components:

• Genetic diversity which refers to the genetic variation that occurs among members of the same species.

• Species diversity (taxonomic diversity) which refers to the variety of species or other taxonomic groups in an ecosystem.

• Ecosystem diversity which refers to the variety of biological communities found on earth.

• Functional diversity which refers to the variety of biological processes, functions or characteristics of a particular ecosystem.

Genetic, species and ecosystem diversity are also often grouped as ‘structural diversity’. An example of species diversity is a measure of the number of all codfish in a community.

An example of functional diversity is the number of filter feeders in an ecosystem compared to the number of grazers. Functional diversity is thought to be one of the main factors determining the long-term stability of an ecosystem and its ability to recover from major disturbances.

Biodiversity encompasses many levels of organization including genes, species, habitats, communities and ecosystems. Although species diversity is the most commonly used measure of taxonomic diversity (or diversity between types of organisms), other measures of taxonomic diversity exist, the most common of which is phyletic diversity. Phyletic diversity is the variation in the working body plans (phyla) of organisms. An example of a phylum is the Arthropoda, which includes organisms such as crabs, lobsters, shrimp as marine animals and insects and spiders as terrestrial organisms.

Why is marine biodiversity important?

Marine organisms contribute to many critical processes that have direct and indirect effects on the health of the oceans and humans. What is obvious is that there are specific species and functional groups that play critical roles in important ecosystem processes, and the loss of these species may have significant influences on the whole ecosystem.

Primary and secondary production are important mechanisms by which marine communities contribute to global processes. It has been estimated that half the primary production on earth is attributable to marine species. Without primary producers in surface waters, the oceans would quickly run out of food, but without planktonic and benthic organisms to facilitate nutrient cycling, the primary producers would quickly become nutrient limited.

The marine ecosystem provide us a lot of goods and services like food provision, nutrient cycling, gas and climate regulation, … .Looking at ecosystems in terms of the goods and services they provide, allows us to realize their full value and our dependency on those systems in the broadest sense.