The introduction of non-native species is killing our wetlands. Native species do not have defenses against these non-native species. Natural threats to wetlands are erosion, subsidence, the sea level rising, droughts, and hurricanes and other storms. The functions of a wetland are numerous. They improve water quality, and they naturally control pollution by removing agricultural chemicals and other pllutants from the surface of the water.
Wetlands are also efficient alternatives for sewage and animal waste treatment.
Wetlands also improve the quality of lakes and reservoirs by filtering sediment from runoff water which helps reduce sedimentation. They help reduce floods by reducing peak water flow from storms and recharging ground water supplies as they release water into the ground. Wetlands are also very crucial providers of important wildlife habitats. Wetlands are among the most biologically productive natural ecosystems in the world. They can be compared to the tropical rainforests and the coral reef.