WETLAND OVERVIEW

ROLL # 397

Introduction

Whether real or fictional, wetlands have significant roles in the physical, biological and cultural geography of the world.

Wetland are the places where the ground is generally saturated or flooded for extended periods during the growing season such that distinctive soils from and specialized vegetation grows under conditions in which oxygen is depleted or absent. such environment includes marshes, fens, bogs and swamps.

They play vital role in the cycling and storage of key nutrients, materials and energy through the Earth’s system.

Wetland components include water, soil, vegetation and wildlife.

They represents the primary sources of fresh water for people in most places around the world.

Wetlands minimize the flooding and storm damage, nourish fisheries, produce fur-bearing animals etc.

Wetlands are situated at the transitions between dry uplands and deep water lake and marine environments.

They viewed as the links that bind together all other habitats and play key roles in the overall environmental system through transfer and storage of materials and energy.

Feedback relationships exists between wetlands and their surroundings.

Wetlands also harbor some of the greatest biodiversity found on the planet.

Many aquatic animals are endemic to isolated wetlands, such as the hundred of fish species found in the lakes of eastern Africa.

How much and where

The total coverage of existing wetlands is estimated to range from at least 7- 10 million km2 , or 5-8 percent of the land.

Bog, swamps, marsh, fen, muskeg and similar habitats are represented in this total.

Distribution of wetlands is not uniform.

The greatest conc. of wetlands is found in boreal and sub boreal regions.

A second conc. in wetland distribution is found in the tropics with a peak abundance just south of the Equator.

The general climatic pattern and distribution of wetlands are influenced substantially by the positions of continents, flow of ocean currents, prevailing winds, mountains and other major geographic features.

Wetland trends

Humans have modified and exploited wetlands in many ways, most of which have led to loss of wetland habitats and their conversion to other land and uses and covers.

It is generally agreed that worldwide at least half of all pre-development wetlands have been lost to human activities.

Elsewhere around the world, similar wetland losses range from over 90 percent in New Zealand to minimal impacts in remote and little-developed regions.

Wetland preservation and protection

Now wetland conservation is a cause with considerable public support around the world. Early efforts focused on wildlife.

US and UK ---Migratory Bird Treaty Act Migratory Bird Hunting and Conservation---

stamp to raise money for preservation. EPA, FWS, NRCS are major agencies involved in

the protection research and regulation. WI is the major global NGO with restoring and

sustaining wetland habitats, resources and biodiversity.

Wetland science

The scientific study of wetlands was traditionally and considered to be a part of biology.

Four unique steps to wetland science are:

1. Wetlands have many special properties not adequately covered in biological specialties.

2. Wetlands of disparate types do have some common properties.

3. Wetland studies require an interdisciplinary approach.

4. Strong scientific understanding of many facets is necessary for the development of policy, regulation and management of wetlands.