According to 700 leading world experts concluding a week-long meeting in Cuiaba, Brazil, resisting pressures to convert wetlands is vital to avoid destroying ecosystems that provide a suite of services essential to humanity, including safe, steady local water supplies, preserving biodiversity and the large-scale capture and storage of climate warming greenhouse gases.
The experts issued the Cuiaba Declaration on July 25, the final day of the 8th INTECOL International Wetlands Conference, convened on the northern edge of the world's largest tropical wetland, the Pantanal.
Wetlands include marshes, tidal marshes, peat bogs, swamps, river deltas, mangroves, tundra, lagoons and river floodplains.
Among other services, they trap and store carbon in submerged organic matter, sustain biodiversity, and produce renewable natural resources, such as fish, natural pasture, timber, and wildlife.
The statement stresses the rising value of wetlands in an increasingly urbanized world, especially such services as water storage and purification, and recreation.
Wetlands are under assault, however, due to agriculture, grazing, aquaculture, dams, waste disposal, invasive species and other problems caused by human activity.
"It is time to recognize the incalculable value of wetlands to all species - ours included," said conference co-chair Paulo Teixeira, Co-ordinator of the Cuiaba-based Pantanal Regional Environmental Programme.
"If we don't plan and invest properly now, the cost to recreate artificially the services wetlands provide will dwarf the cost of preserving and protecting them in the first place," he added.
In their statement, conference delegates from 28 nations lament "inadequate national development policies, lack of implementation of existing laws, and the lack of long-term land use planning that negatively affect wetlands on public and private property."
They also call for help establishing such basic information tools as a mapped inventory of wetlands based on universally-accepted definitions, which as yet do not exist.
They warn against creating energy and food croplands at the expense of natural vegetation and of carelessly allowing agriculture to encroach on wetlands, which causes damage through sediment, fertilizer and pesticide pollution.
The statement said that development in and around wetlands must be preceded by "sound cost-benefit analyses, including environmental and social parameters," adding that "mitigation of many negative side-effects is not possible" once the damage is done.
"A modern wetland policy based on sound scientific knowledge and able to reconcile economic development with environmental protection and social welfare is required in all countries," it said.