Different types of ecosystems require different conservation approaches. Lakes differ fundamentally from meadows; forest steppe ecosystems from taiga forests and so on. Peatlands share many attributes with lakes and are considered freshwater ecosystems, but also they share many features of terrestrial ecosystems. Peatlands differ from other ecosystem types in a number of properties. This section reviews how these affect biodiversity at the genetic, phenetic, species and ecosystem level. Peatlands possess a high level of autonomy and integrity and consequently constitute outstanding examples of ecosystem biodiversity. Peatlands are complex but clearly organised ecosystems. Their high ecosystem diversity is related to their obvious hierarchical organisation over various scales. Peatland organisms must cope with many inimical conditions. This requires them to adapt their physiology, anatomy, morphology, life cycle and behaviour. The continuous accumulation of peat, the special temperature regime, the high water level and the consequent scarcity of oxygen in the root layer require mire plants to adapt their physiology, anatomy and growth forms. Many peatland plants have aerenchyma of loosely arranged cells with air-filled cavities that allow the exchange of gases between the shoot and the root and increase their buoyancy. Other adaptations to wetness include growth in tussocks, floating mats and rafts, as well as the development of shallow root systems and adventitious roots on stems. Mire plants generally show adaptations to nutrient shortage, like cation exchange in Sphagnum, stunted growth in trees, and parasitism and carnivory. Symbiosis with fungi or bacteria can help to retrieve scarce nutrients (Schwintzer 1983, Saur 1998, Sapp 2004) or even increase effectiveness of photosynthesis (Raghoebarsing 2005).

Peatlands support both phenetic and ecosystem diversity. High phenetic diversity is associated with high habitat diversity. A large variety of growth forms compensates a smaller diversity of species. Different growth forms of Scots' pine trees occurring in the same peatland (From prostate 10-20cm tall to straight- stemmed several meters tall) were originally described by Carl Weber in 1902.

Also the fauna of mires is influenced by the scarcity of nutrients and ions, the acidity of the mire water, the relative coolness, and (in the case of non-forested mires) the strong temperature fluctuations (Joosten and Clarke 2002).

Organisms, forms and species in peatlands depend closely upon one another in terms of food supply, reproductive mechanisms (pollination) and shelter. These connections are often critical for survival, so that loss of one species will lead to the loss of other dependent species. The high demands peatland habitat places on organisms and the resulting low species diversity have led to the co-evolution of strong interactions and dependencies in peatland communities that may lead to the extinction of other species when one species is lost.