lake
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...
in southern
Stockholm
Stockholm () is the Capital city, capital and List of urban areas in Sweden by population, largest city of Sweden as well as the List of urban areas in the Nordic countries, largest urban area in Scandinavia. Approximately 980,000 people liv ...
,
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...
, shared by the four municipalities Stockholm,
Haninge
Haninge Municipality (''Haninge kommun'') is a municipality in Stockholm County in east central Sweden. Its seat is located in Handen, a part of the Stockholm urban area.
Haninge Municipality was formed in 1971 when ''Västerhaninge'' and ''Öst ...
,
Huddinge
Huddinge Municipality ( sv, Huddinge kommun) is a municipalities of Sweden, municipality in Stockholm County, east central Sweden. Its seat is located in Huddinge (), which is a part of Stockholm urban area.
The municipality is, with its approxima ...
, and Tyresö.
While much of the surrounding area is used for one-family houses, the lake and the green space north of it are considered to be of great recreational and natural importance and forms part of a suggested nature reserve around lake Flaten.Drevviken
Catchment area
Approximately two-thirds of the catchment area is occupied by settlements, mostly one-family houses. Three major industrial areas are located within the catchment area which is mostly dominated by forests with minor open grasslands. North of the lake is a
deciduous forest
In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...
containing
herbaceous plant
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of t ...
s and
rocks
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's ...
covered with
brushwood
Brushwood can mean:
* ''Melaleuca uncinata'' or Broombrush
* Brushwood, New South Wales, a rural community in the central east part of the Riverina region of New South Wales, Australia
* Brian Brushwood
Brian Allen Brushwood (born January 17, ...
s and
lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.fluvio-glacial deposit with a broad irrigated marsh and a scenic pine forest; and a
wetland
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
which is the remnant of a former
stream
A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...
.Vattenprogram, p 10.3-10.6
Environmental influence
Stormwater
Stormwater, also spelled storm water, is water that originates from precipitation (storm), including heavy rain and meltwater from hail and snow. Stormwater can soak into the soil ( infiltrate) and become groundwater, be stored on depressed la ...
from several suburbs empties into the lake around which are three allotment-gardens. Potentially hazardous activities in the area include a petrol station, an asphalt works, concrete industry, small scale industries, and a closed stock pile covering 9 hectare containing excavated material from the demolition of a major area in central Stockholm in the 1960s. Several traffic routes and a metro track passes through the catchment area.
Flora and fauna
During summers
phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'.
Ph ...
are dominated by
cyanobacteria
Cyanobacteria (), also known as Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name ''cyanobacteria'' refers to their color (), which similarly forms the basis of cyanobacteria's common name, blu ...
and occasionally
diatom
A diatom (Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising sev ...
s, most commonly ''Aphanizomenon cf gracile'' but also ''Pseudanabaena limnetica'', ''Planktolyngbya'' sp. and various species of ''
Anabaena
''Anabaena'' is a genus of filamentous cyanobacteria that exist as plankton. They are known for nitrogen-fixing abilities, and they form symbiotic relationships with certain plants, such as the mosquito fern. They are one of four genera of cyanob ...
'', of whom only ''
Aphanizomenon
''Aphanizomenon'' is a genus of cyanobacteria that inhabits freshwater lakes and can cause dense blooms. They are unicellular organisms that consolidate into linear (non-branching) chains called trichomes. Parallel trichomes can then further uni ...
'' is potentially poisonous and ''Anabaena'' frequently causes
algal bloom
An algal bloom or algae bloom is a rapid increase or accumulation in the population of algae in freshwater or marine water systems. It is often recognized by the discoloration in the water from the algae's pigments. The term ''algae'' encompas ...
.
Carapace
A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...
flagellate
A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and their ...
s such as ''
Ceratium hirundinella
The genus ''Ceratium'' is restricted to a small number (about 7) of freshwater dinoflagellate species. Previously the genus contained also a large number of marine dinoflagellate species. However, these marine species have now been assigned to ...
'' and various
dinoflagellate
The dinoflagellates (Greek δῖνος ''dinos'' "whirling" and Latin ''flagellum'' "whip, scourge") are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered algae. Dinoflagellates are ...
s, are few but important to the lake's
biomass
Biomass is plant-based material used as a fuel for heat or electricity production. It can be in the form of wood, wood residues, energy crops, agricultural residues, and waste from industry, farms, and households. Some people use the terms bi ...
. Various
rotifer
The rotifers (, from the Latin , "wheel", and , "bearing"), commonly called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic pseudocoelomate animals.
They were first described by Rev. John H ...
s are common
zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...
copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor) ...
s can also be found. An inventory of
aquatic plant
Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...
s in the lake in 1998 resulted in a list of some 30 species, including branched bur-reed and Nuttall's waterweed (the latter introduced in Europe during the 20th century and relatively new in Sweden.)Vattenprogram, p 10.6-10.7
A list of
dragonfly
A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of true dragonfly are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threate ...
variable
Variable may refer to:
* Variable (computer science), a symbolic name associated with a value and whose associated value may be changed
* Variable (mathematics), a symbol that represents a quantity in a mathematical expression, as used in many ...
, and blue-tailed damselflies. Sample fishing in 1997 documented a dozen species, most notably
roach
Roach may refer to:
Animals
* Cockroach, various insect species of the order Blattodea
* Common roach (''Rutilus rutilus''), a fresh and brackish water fish of the family Cyprinidae
** ''Rutilus'' or roaches, a genus of fishes
* California roach ...
and
zander
The zander (''Sander lucioperca''), sander or pikeperch, is a species of ray-finned fish from the family Percidae, which includes the perches, ruffes and darters. It is found in freshwater and brackish habitats in western Eurasia. It is a popul ...
but also
northern pike
The northern pike (''Esox lucius'') is a species of carnivorous fish of the genus '' Esox'' (the pikes). They are typical of brackish and fresh waters of the Northern Hemisphere (''i.e.'' holarctic in distribution). They are known simply as a ...
,
perch
Perch is a common name for fish of the genus ''Perca'', freshwater gamefish belonging to the family Percidae. The perch, of which three species occur in different geographical areas, lend their name to a large order of vertebrates: the Percif ...
,
eel
Eels are ray-finned fish belonging to the order Anguilliformes (), which consists of eight suborders, 19 families, 111 genera, and about 800 species. Eels undergo considerable development from the early larval stage to the eventual adult stage ...
,
trout
Trout are species of freshwater fish belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of the subfamily Salmoninae of the family Salmonidae. The word ''trout'' is also used as part of the name of some non-salmoni ...
, - of which some have been introduced into the lake - and many others. The lake was struck by
crayfish plague
Crayfish plague (''Aphanomyces astaci'') is a water mold that infects crayfish, most notably the European ''Astacus'' which dies within a few weeks of being infected. When experimentally tested, species from Australia, New Guinea and Japan were a ...
in 1950 but
crayfish
Crayfish are freshwater crustaceans belonging to the clade Astacidea, which also contains lobsters. In some locations, they are also known as crawfish, craydids, crawdaddies, crawdads, freshwater lobsters, mountain lobsters, rock lobsters, mu ...
was reintroduced around 1970. North-east of the lake smooth newt,
common frog
The common frog or grass frog (''Rana temporaria''), also known as the European common frog, European common brown frog, European grass frog, European Holarctic true frog, European pond frog or European brown frog, is a semi-aquatic amphibian o ...
, and
common toad
The common toad, European toad, or in Anglophone parts of Europe, simply the toad (''Bufo bufo'', from Latin ''bufo'' "toad"), is a frog found throughout most of Europe (with the exception of Ireland, Iceland, and some Mediterranean islands), in ...
were documented in 1996. Noctule bats documented in the area, previously assigned the
status
Status (Latin plural: ''statūs''), is a state, condition, or situation, and may refer to:
* Status (law)
** City status
** Legal status, in law
** Political status, in international law
** Small entity status, in patent law
** Status conference ...
near-threatened
A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...
, are now considered
least concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
.
Soprano pipistrelle
The soprano pipistrelle (''Pipistrellus pygmaeus'') is a small species of bat. It is found in Europe and often roosts on buildings.
Taxonomy
Until 1999, the soprano pipistrelle was considered as conspecific with the common pipistrelle
The co ...
has also been seen along the northern shore of the lake. Couples of
great crested grebe
The great crested grebe (''Podiceps cristatus'') is a member of the grebe family of water birds noted for its elaborate mating display.
Taxonomy
The great crested grebe was formally described by the Swedish naturalist Carl Linnaeus in 1758 in t ...
s and
common tern
The common tern (''Sterna hirundo'') is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migrator ...
s are breeding by the lake together with colonies of
black-headed gull
The black-headed gull (''Chroicocephalus ridibundus'') is a small gull that breeds in much of the Palearctic including Europe and also in coastal eastern Canada. Most of the population is migratory and winters further south, but some birds res ...
s,
mute swan
The mute swan (''Cygnus olor'') is a species of swan and a member of the waterfowl family Anatidae. It is native to much of Eurosiberia, and (as a rare winter visitor) the far north of Africa. It is an introduced species in North America, home ...
s,
Canada geese
The Canada goose (''Branta canadensis''), or Canadian goose, is a large wild goose with a black head and neck, white cheeks, white under its chin, and a brown body. It is native to the arctic and temperate regions of North America, and it is o ...
lesser black-backed gull
The lesser black-backed gull (''Larus fuscus'') is a large gull that breeds on the Atlantic coasts of Europe. It is migratory, wintering from the British Isles south to West Africa. It has increased dramatically in North America, most common alo ...
* {{cite web
, url = http://www.drevviken.com/
, title = Drevviken - Långsjöns Fiskevårdsförening
, accessdate = 2007-05-27
, language = Swedish
(A local angling society.)
Geography of StockholmLakes of Stockholm County