Dam

For alternative betydninger, seDam (flertydig).(Se også artikler, som begynder med Dam)

Endamer et lillevandhul,der er så lavvandet at lyset normalt kan trænge ned til bunden. Damme adskiller sig fra de størresøer,ved at de ikke udviklerspringlag,og fravandpytterne,ved at de indeholder vand hele året rundt. Man skelner mellem naturlige og kunstige damme. En kunstig dam kan f.eks. være enmølledam,branddam,fiskedam(f.eks.ørreddam,karpedam) ogregnvandsdam(regnvandsreservoir).

Damme er oftenæringsrige(andedamme endog ekstremt næringsrige). Planterne består afrørskovsplanter,flydebladsplanter,bundplanter (rankegrøde) ogplanteplankton. Dyrelivet svarer til søernes dyreliv, dog ofte repræsenteret af arter, der er mere tolerante over for dårlige iltforhold. Man kan groft inddele dyrene ibunddyr,dyr der lever på planterne ogdyreplankton(f.eks.dafnier), samt større dyr, herunder bl.a.fiskogpadder.

Datadreven amerikansk forskerdefinition

En samling forskere har lavet en undersøgelse, hvor de definerer en dam som: Citat: "Ponds are small and shallow waterbodies, with a maximum surface area of five hectares, a maximum depth of 5 meters and less than 30% emergent vegetation." Det kan oversættes til: "Damme er små lavvandedevandmasser,med et maksimalt overfladeareal på 5hektar,en maksimal dybde på 5 meter og mindre end 30% fremvoksende vegetation. "^[1]

Se også

Litteratur

Hans Scherfig:Dammen,illustreret af Elisabeth Karlinsky, 1958, 3. udg. 1993,ISBN 87-00-15148-3,en fin naturbeskrivelse.

Referencer

^Cornell University. (2022, July 5). What is a pond? Study provides first data-driven definition. ScienceDailyCitat: "...Their conclusion: Ponds are small and shallow waterbodies, with a maximum surface area of five hectares, a maximum depth of 5 meters and less than 30% emergent vegetation...The researchers found that ponds are not the same aslakesorwetlands,however. Further examination of the literature revealed that ponds have distinct ecological structures and function that make their categorization with either lakes or wetlands problematic... "

Eksterne henvisninger

Iowa State University (2008, May 8). Ponds Found To Take Up Carbon Like World's Oceans. ScienceDaily. Retrieved May 8, 2008Citat: "..." Aquatic ecosystems play a disproportionately large role in the global carbon budget, "Downing said...The combined effect is that farm ponds could be burying as much carbon as the world's oceans, each year...It may be that ponds will be the modern equivalent of the swamps that formed coal in the past. But before we all rush into making ponds to trap carbon we need to do some basic research here in the UK..."

Søsterprojekter med yderligere information:

[1] Cornell University. (2022, July 5). What is a pond? Study provides first data-driven definition. ScienceDailyCitat: "...Their conclusion: Ponds are small and shallow waterbodies, with a maximum surface area of five hectares, a maximum depth of 5 meters and less than 30% emergent vegetation...The researchers found that ponds are not the same aslakesorwetlands,however. Further examination of the literature revealed that ponds have distinct ecological structures and function that make their categorization with either lakes or wetlands problematic... "

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