Arctic freshwater ecosystems divided into three main types: flowing water (river and streams), permanent standing water (lakes and ponds) and wetlands such as peatlands and bogs . Wetlands are among the most abundant and productive aquatic ecosystems in the Arctic.They are ubiquitous and characteristic features throughout the Arctic and almost all are created by the retention of water above the permafrost. They are more extensive in the southern Arctic than the high Arctic, but overall, cover vast areas – up to 3.5 million km2 or 11% of the land surface. Several types of wetlands are found in the Arctic, with specific characteristics related to productivity and climate. Bogs, for example, are nutrient poor and have low productivity but high
