Ecosystem services

'Ecosystem goods', such as food, and 'services', such as waste assimilation, represent the benefits humans obtain from a properly functioning ecosystem and are usually referred together as 'ecosystem services'. Unsurprisingly a large number of ecosystem services have been identified, especially for the oceans which cover the majority of the planet and the coastal zone where the majority of humans live.

 

These include: gas regulation (e.g. maintaining a balanced chemical composition in the atmosphere), climate regulation (e.g. control of global temperature, precipitation, greenhouse gas regulation, cloud formation), disturbance regulation (e.g. storm protection, flood control, drought recovery), water regulation (e.g. regulation of global, regional and local scale hydrology through currents and tides), water supply (e.g. storage of water returned to land as precipitation), erosion and sediment transport/deposition (e.g. moving sediments from source areas and replenishing depositional areas), nutrient cycling e.g. the storage, internal cycling, processing and acquisition of nutrients, nitrogen fixation, phosphorus cycles), waste treatment (e.g. the breakdown of excess xenic and toxic compounds), biological control (e.g. the trophic-dynamic regulation of populations), refugia (e.g. feeding and nursery habitats for resident and transient populations of harvested species), food production (e.g. the portion of gross primary production which is extracted as food for humans), raw materials (e.g. the portion of gross primary production which is extracted as fuel or building material), genetic resources (e.g. sources of unique biological materials for medicines), recreation (e.g. opportunities for tourism, sport and other outdoor pastimes) and cultural (e.g. opportunities for aesthetic, artistic, educational, spiritual activities).

 

The value (the theoretical cost of artificially replacing the services were they not to be provided by nature) to humanity of these ecosystem services has been estimated at $8400 billion per year for the open oceans and 1.5 times this for coastal ecosystems. Consumptive use (production of food and raw materials) is a minor (<5%) component and therefore the true value of marine ecosystems is in non- consumptive use. However quantifying such use is notoriously hard.