环境科学论文代写 Opportunities Exist For Their Restoration And Creation
Wetlands contribute towards some of the most biologically diverse ecosystems that exist on our planet, providing habitats for a huge variety of both aquatic and terrestrial wildlife and plants by acting as biological and genetic pathways between water and land. They also support endemic and migratory species by providing valuable rearing and breeding habitats. In fact, within British wetlands, there are more than 3,500 species of invertebrates, 150 aquatic plants, 22 ducks and 39 wader species, as well as Britain's native amphibians that depend on these wetlands for breeding (1). Occurring naturally on almost all continents of the Earth, wetlands are ecologically important in the environment and provide many essential processes for example water purification, flood control and shoreline stability. These provide a variety of aquatic habitats such as swamps, marshes and bogs. In addition, they are important buffers against extreme weather; absorbing water during heavy rain to help prevent flooding and providing the surrounding areas with water during draughts. They support and restore underground water systems, store sediments and process pollution while being home to a huge variety of species. With controlled flooding, wetland habitats can increases fish abundance and species richness (2,3). The water found in such habitats includes freshwater (4).
The hydrological cycle is an essential process regarding wetlands and is vital in keeping a constant balance of water, both above and below sea level. Water is transferred from one reservoir to another via processes including condensation, evaporation, infiltration and precipitation, providing a global water recycling system and contributing towards producing a critical resource for human well-being; clean running water (5). Freshwater wetlands rely on the hydrological cycle because as the cycle proceeds, the water is purified, which in turn produces freshwater.
Freshwater habitats are among the most productive ecosystems in Britain and include both flowing waters (lotic ecosystems) such as rivers, and still standing waters (lentic ecosystems) such as lakes. They can regulate flooding, erosion, sedimentation, local climates and water quality, and also facilitate the dilution and disposal of pollutants (6). In particular, freshwater ecosystems control runoff processes from the land to rivers, floods and droughts (7) and water quality (8). This is absolutely essential for the ecosystems and wildlife to which they supply for.
The distribution of freshwater and wetland habitats across Britain is uneven, with Scotland holding the majority of the freshwater in the UK, specifically 70% by area, and more than 90% by volume (9). In addition, there are almost 570 lakes in Wales and a much larger number of smaller ponds and wetland pools (6).
However, despite this, lowland wetland and freshwater habitats have now become a conservational priority in Britain, following a dramatic decline of area within the last century. They are now among the rarest and most threatened habitats in Britain, which of course has dramatic consequences and effects for the plants and animals to which they provide resources for. Both lowland raised bogs and fen are referred to as priority habitats within the UK Biodiversity Action Plan. Also, there are six separate lowland wetland habitat types under Annex I of the EU Habitats Directive (10).
These habitats and the plants and wildlife they support are subject to many various pressures and threats. These must be fully understood before any action can be taken to restore, protect and recreate the habitat and associated ecosystem. The three primary threats regarding these habitats are land-use disturbances, altered hydrologies, and the introduction of non-native species (11).
环境科学论文代写 Opportunities Exist For Their Restoration And Creation
