Wetlands: History, current status, and future

Wetlands have been intricately linked with humankind throughout the ages. Evidence of rice culture dates to the earliest age of humans, long before the era of historical records. Drain‐field and raised‐field agriculture occurred in wetlands throughout large areas of Mesoamerica before Hispanic exploration of the region. About 40% of the world's population uses rice as a major staple; rice culture currently occupies about 15% of the world's wetland area. Wetlands are valued for high biological productivity; as filters, sinks, and transformers for sediments, nutrients, and pollutants; and as buffers between aquatic systems and human activities on upland areas. Because of their varied ecological functions, wetlands are of interest to ecotoxicologists as potential sites for detoxifying pollutants. Estimates are that wetlands occupy about 3 to 6% of the world's land area. Attempts to define, delineate, monitor, and regulate the use of wetlands in the United States have proven to be extremely complex. Considerable progress has been made in classifying and monitoring changes in wetland areas on a nationwide basis, but less success has been achieved in defining and delineating wetlands. The United States experience should be a useful model for developing countries to study as they attempt to deal with wetland management and protection. As long as the world's population continues to grow at exponential rates, it seems highly probable that pressure to use wetlands to meet society's demands will increase. Consequently, opportunities to set aside reserves will decrease, and the role that wetlands play in maintaining quality of life will depend more and more on our collective ability to develop and promote compatible uses on wetlands.