Lakes, reservoirs and ponds
There are many lakes and ponds in Northern Ireland, of varying sizes. The largest are Lough Neagh (the largest body of freshwater in the British Isles), Upper Lough Erne and Lower Lough Erne. An inventory of Northern Ireland lakes, with statistics such as surface areas and number of lakes at different altitudes, is available from the Stationery Office, Belfast: The Lakes of Northern Ireland: an annotated inventory by S.J. Smith, S. A. Wolfe-Murphy, I Enlander and C. E. Gibson, Countryside & Wildlife Research Series No.3, 1991.
The forerunner of the Environment & Heritage Service financed an intensive survey of Northern Ireland freshwater lakes during the late 1980s. The plant data from this Northern Ireland Lake Survey is included within the Vascular Plant Database for Northern Ireland (VPDNI).
Lakes are a species-rich habitat in general, although the richness of an individual lake is governed by many factors such as water chemistry, local geology, and altitude. Pollution by run-off from surrounding farmland may adversely affect the biology of lowland lakes. In very general terms, lowland lakes are more species-rich and have more nutrient-rich waters whereas upland lakes tend to be nutrient-poor and contain fewer plant species. Lowland lakes are frequently surrounded by marshy vegetation which grades into fen, upland lakes are frequently surrounded by acid bog.
Many lakes are used as water reservoirs, with water levels artificially raised by dams; other reservoirs are entirely artificial. The vegetation of reservoirs is not fundamentally different from that of natural lakes.
Significant or characteristic species of lowland lakes
(Included are: common or frequent species which would be expected to occur in most lowland lakes, and species which are rare but whose main habitat is lowland lakes.)
The three categories (1,2,3 below) are not always clearly separable.
Significant or characteristic species of upland lakes
(Included are: common or frequent species which would be expected to occur in most upland lakes, and species which are rare but whose main habitat is upland lakes.)
The three categories (1,2,3 below) are not always clearly separable.