2 February is marked as World Wetlands Day to raise global awareness about the vital role of wetlands for people and our planet. Wetlands are land areas that are saturated or flooded with water either permanently or seasonally. Inland wetlands include marshes, ponds, lakes, fens, rivers, floodplains, and swamps. Coastal wetlands include saltwater marshes, estuaries, mangroves, lagoons and even coral reefs. Fishponds, rice paddies, and saltpans are human-made wetlands. Wetlands are indispensable for the countless benefits or “ecosystem services” that they provide humanity, ranging from freshwater supply, food and building materials, and biodiversity, to flood control, groundwater recharge, and climate change mitigation. Wetlands are vital for human survival. They are among the world’s most productive environments; cradles of biological diversity that provide the water and productivity upon which countless species of plants and animals depend for survival. Wetlands can be thought of as "biological supermarkets." They provide great volumes of food that attract many animal species. These animals use wetlands for part of or all of their life-cycle. Dead plant leaves and stems break down in the water to form small particles of organic material called "detritus." This enriched material feeds many small aquatic insects, shellfish and small fish that are food for larger predatory fish, reptiles, amphibians, birds and mammals. Wetlands are the world’s water filters. They trap pollutants such as phosphorus and heavy metals in their soils, transform dissolved nitrogen into nitrogen gas, and break down suspended solids to neutralize harmful bacteria.
It is speculated that upwards of half of the world’s wetlands have disappeared since 1900, despite their value to the human population. In some places the pace of wetlands destruction occurs at incredible speeds. In the Philippines, 80% of coastal wetlands have been degraded, drained or destroyed in the last 30 years. Without wetlands, human communities lose many of the vital services that they provide, including water purification, flood control, and food supply. Wetlands are often underappreciated because they are viewed as being more valuable for their water and undeveloped land than the ecosystem services they provide. They are often drained to make room for agriculture or human settlements. And any wetlands nearby left untouched may lose their own water to this development. Human activity is probably the most prevalent cause of wetland destruction or degradation. Development -- whether it's drainage, damming to form lakes or ponds, adding pavement, or diverting water flow -- affects the soil's hydrologic condition, or the presence of water in the soil. If there's no water, there's no wetland. Overgrazing by animals can cut down on the area's vegetation, leaving wetlands susceptible to erosion. Natural disasters like hurricanes or flooding can greatly erode a wetland area. While wetlands act as a buffer against these weather occurrences, they also pay the price with diminished vegetation and pollution from runoff. Pollution also degrades wetlands and water quality. Again, wetlands act as a natural filter for polluted water, but they can only absorb so much. Pollution enters the water table through pesticides, sediment, sewage, fertilizers and many other forms. Once a wetland is polluted, it's difficult to clean it up. The best way to keep wetlands clean is to protect them from pollution in the first place, by ensuring a contaminant-free water supply.
Spreading awareness by initiating educational programs about the importance of wetlands in local schools, colleges and among the general public in the vicinity of the water bodies, besides constant monitoring of wetlands for their water quality, would provide vital inputs to safeguard the wetlands from further deterioration. Healthy vegetation is crucial for sustaining life in the wetlands. This includes upland vegetation, fringing vegetation and aquatic plant-life. Wetland vegetation is highly specialized, in that it has evolved to thrive in varying conditions of dampness and salinity.
Within the wetland catchments, ecosystems flourish based on an energy exchange between living organisms and the non-living environment. Leaves or branches from overhanging trees and shrubs, fall and are broken down by microbes, bacteria and fungi. These, in turn, become food for larger animals within the food web. We can help in the conservation and rehabilitation efforts – by planting native flora, creating habitats for wildlife and participating in citizen science projects and initiatives.
Image credit: Wetlands International
Comments