In peatlands, water, peat and plants are strongly interconnected. If any one of these components is altered, the nature of the peatland will change.

Peatlands are wetland ecosystems that are characterized by the accumulation of organic matter (peat), which is derived from dead and decaying plant material under conditions of permanent water saturation. There are many different types of peatland, depending on geographic region, terrain and vegetation type. A major distinction is between bogs (which are fed only by precipitation and are nutrient-poor) and fens (which are fed by surface or ground water as well as precipitation and tend to be more nutrient rich). Peatlands may be naturally forested or naturally open and vegetated with mosses, sedges or shrubs. Peat formation is strongly influenced by climatic conditions and topography.

In northern latitudes or high altitudes the temperature may be high enough for plant growth but too low for vigorous microbial activity. Significant areas of peatlands are found in tropical and sub-tropical latitudes where high plant productivity combines with slow decomposition as a result of high rainfall and humidity. In some cases peatlands were formed during wetter climatic periods thousands of years ago but, in the prevailing drier climate, may no longer accumulate peat.

• The major characteristics of natural peatlands include permanent water logging, development of specific vegetation, the consequent formation and storage of peat and the continuous (upward) growth of the surface.
   
• Peatland distribution, peat formation and storage are primarily a function of climate, which determines water conditions, vegetation productivity and the decomposition rate of dead organic material.
   
• Peatlands are found in almost every country, but occur primarily in the boreal, subarctic and tropical zones, as well as in appropriate zones in mountains. More detailed assessment of their extent, nature and status is needed. Many peatlands are not recognized as such but are classified as marshes, meadows, or forests.
   
• As a result of different climatic and biogeography conditions, a large diversity of peatland types exists. However, because of similar ecohydrological processes, they share many ecological features and functions.
   

• In northern regions and highlands, peatlands and permafrost are mutually dependent. 

• The complex relationship between plants, water, and peat makes peatlands vulnerable to a wide range of human interferences.
   

peat formation Peat accumulates at a rate of about 0.5 - 1 mm per year (or 5-10 mover 10,000 years) with strong local variations. Peat can be formed from mosses, sedges,grasses, shrubs or trees. In northern regions, mosses are the main peat-forming plants while trees are the main ones in the tropics. Most peatlands that exist today formed in the last 15,000 years since the last Ice Age.
Peat consists of accumulated dead plant material of which at leasts 50% is carbon	Water saturation means that plant remains decompose slowly and form peat