About 3% of the total amount of water on the planet is fresh, and half of that is locked up in icecaps and glaciers, so it is unavailable for human use. The principal sources of fresh water that are available to humans reside in freshwater systems and associated habitats such as lakes, rivers, wetlands, and shallow groundwater aquifers. For these reasons, freshwater ecosystems, and the watersheds and basins throughout which freshwaters flow, are vital for human and freshwater dependent species survival.

Ecosystem services (ES) are the ecological conditions and processes that regulate and provide for human well-being (Daily, 1997). The Millennium Ecosystem Assessment found that nat

About 3% of the total amount of water on the planet is fresh, and half of that is locked up in icecaps and glaciers, so it is unavailable for human use. The principal sources of fresh water that are available to humans reside in freshwater systems and associated habitats such as lakes, rivers, wetlands, and shallow groundwater aquifers. For these reasons, freshwater ecosystems, and the watersheds and basins throughout which freshwaters flow, are vital for human and freshwater dependent species survival.

Ecosystem services (ES) are the ecological conditions and processes that regulate and provide for human well-being (Daily, 1997). The Millennium Ecosystem Assessment found that natural ecosystems provide drinking, washing, fisheries, agriculture, transportation, industrial processes, and energy generation and electrical generation services–benefitting billions of people (MEA 2005a). Less tangible, yet critical freshwater-related services such as flood control, purification of waste, and delivery of nutrient-rich sediments to floodplains are also valuable roles ecosystems play.

History of Freshwater Ecosystem

Freshwater ecosystems are home to the highest concentrations of species compared to terrestrial or marine ecosystems. The extensive geographic barriers between freshwater ecosystems have led to particularly high levels of endemism. Regrettably, this species richness coupled with limited resilience and growing threats mean that freshwater dependant species are in substantial decline and top lists of taxa significantly threatened with extinction. A study of 10,000 fishes revealed habitat alteration and introduced species were the largest threats, followed in decreasing order by overfishing, pollution, disease/parasites, hybridization and deliberate eradication. More than 126,000 species rely upon freshwater for some or all of their life cycle. The MEA identified the major threats to freshwater ecosystems coming from dams and infrastructure, excessive water extraction, climate change, invasive species, over-fishing and pollution (MEA 2005b).

Freshwater ecosystems are home to the very best concentrations of species compared to terrestrial or marine ecosystems. The in depth geographic barriers between fresh ecosystems has junction rectifier to particularly high levels of together. Unfortunately, this species richness not to mention restricted resilience and growing threats mean that fresh dependant species are in substantial decline and high lists of taxa considerably vulnerable with extinction. A study of 10,000 fishes disclosed habitat alteration and introduced species were the most important threats, followed in decreasing order by overfishing, pollution, disease/parasites, cross and deliberate destruction. The MEA knew the main threats to fresh ecosystems coming back from dams and infrastructure, excessive water extraction, temperature change, invasive species, over-fishing and pollution (MEA 2005b).

Freshwater ecosystems can't be separated from terrestrial habitats in terms of fresh flows and the hydrologic cycle. For instance, groundwater recharge happens higher than ground but flows underground, evaporation from soils into the atmosphere then falls once more as precipitation, and transpiration from plants returns water to the atmosphere. Similarly, land and water use and management activities should be examined along, significantly once operating towards goals of healthy ecosystems, various species populations, and clean and comfortable provides of fresh for people. Links between ecosystems and watersheds, that govern the patterns and temporal order of water flows, offer a whole image linking bio-physical to ecological and economic concerns.

Moreover, the massive a part of the earth’s continental fresh (50.1%) is frozen in icecaps and glaciers. The importance of this frozen water to international flows of water, and also the ecology and human livelihoods these support, shouldn't be underestimated. The impacts of temperature change also are accelerating glacial melting and provides of fresh is also rife flowing from some places just like the chain of mountains and high mountain chain, but are going to be lost in the medium to long term as natural water storage isn't any longer accessible. Temperature change and co-dependent variable, which, once plus development, can greatly impact clean water convenience and flooding vulnerability. Development decision-making, doesn't sadly usually acknowledge the vital role that ecosystems play in providing for freshwater-related services, nor will it account for adverse trade-offs that may occur between services, if larger scale landscapes and system processes aren't thought-about. For instance, forestation to sequester carbon is also a vital measure to combat temperature change; but this must be planned rigorously since immature trees transpire plenty of water and will cut back inflows into already over-exploited rivers.

Critical Take on Global Level

Global understanding of scheme services – and the key role of water - has been growing. The Middle East Assessment (MEA 2005a) and its wetlands and water synthesis (MEA 2005b), the UNEP Global Environmental Outlook (UNEP 2007), and different reports demonstrate the role of scheme services in managing global climate change and fresh ecosystems. The political economy of Ecosystems and multifariousness (TEEB) study goes a step by proposing systems to price these services, while the Ramsar Convention and Convention on Biological Diversity have printed specific steerage for valuing the benefits derived from land scheme services. The term “ecosystem services” is not nonetheless wide adopted by international agencies yet the Ramsar Convention on Wetlands’ uses “ecosystem benefits/services” and needs member states to keep up them in managing their wetlands (Ramsar 2008a). The UN Food and Agriculture Organization have conjointly established payments for environmental services program (FAO 2009).