Historical Land Loss in Coastal Louisiana -
Louisiana has lost 1,900 square miles of land since the 1930's (Barras et al. 1994, Barras et al. 2003, Dunbar et al. 1992). Currently Louisiana has 30% of the total coastal marsh and accounts for 90% of the coastal marsh loss in the lower 48 states (Dahl 2000, Field et al. 1991, USGS 2003).
Current Rate of Coastal Land Loss -
Between 1990 and 2000 wetland loss was approximately 24 square miles per year, that is one football field lost every 38 minutes. The loss over the next 50 years with current restoration efforts is expected to be 500
square miles (Barras et al. 2003).
For further information on the Breaux Act or Restoration Projects in Louisiana,
contact the Breaux Act home page (http://www.lacoast.gov),
the OCRM home page (http://www.savelawetlands.org),
the Coast 2050 home page (http://www.coast2050.gov)
Causes of Wetland Loss
Despite all the benefits provided by wetlands, the United States loses about 60,000 acres of wetlands each year. It is also estimated that more than 220 million acres of wetlands are thought to have existed in the lower 48 states in the 1600's. Since that time, extensive losses have occurred, and more than half of our original wetlands have been drained and converted to other uses. The mid-1950's to the mid-1970's were a time of major national wetland loss. The very runoff that wetlands help to clean can overload and contaminate these fragile ecosystems. In addition, non-native species of plants and climate changes contribute to wetland loss and degradation.
Human activities cause wetland degradation and loss by changing water quality, quantity, or flow rates; increasing pollution and change the make-up of species within a habitat. These changes occur when wetland ecosystems are disturbed and/or non-native species are introduced to a habitat.
A wetland's characteristics evolve when the soil is saturated with water for a period of time each year. Any change in this process can dramatically impact the soil, plants, and animals that live there. Here are some common human causes of hydrologic changes to wetlands.