Lappkärret is a small

lake A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from ...

Norra Djurgården NORRA or Norra may refer to: * Nordic Regional Airlines, a Finnish airline operating on behalf of, and formerly majority-owned by, Finnair * National Off-Road Racing Association The National Off-Road Racing Association (usually abbreviated NORRA) i ...

in north-eastern

Stockholm Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

, near

Stockholm University Stockholm University (SU) () is a public university, public research university in Stockholm, Sweden, founded as a college in 1878, with university status since 1960. With over 33,000 students at four different faculties: law, humanities, social ...

. It is one of six lakes in

Djurgården Djurgården ( or ) or, more officially, , is an island in central Stockholm, Sweden. Djurgården is home to historical buildings and monuments, museums, galleries, the amusement park Gröna Lund, the open-air museum Skansen, the small resident ...

, the others being: Lillsjön, Uggleviken,

Isbladskärret Isbladskärret is a small lake on Djurgården, an island in central Stockholm, Sweden. The lake is much appreciated among bird-watchers, and, being part of the Royal National City Park, also carefully monitored by several organizations, including ...

, Laduviken, and Spegeldammen. Through its location in the

Royal National City Park The Royal National City Park () is a national urban park, established by the Swedish Parliament in 1995, and located in the municipalities of Stockholm, Solna and Lidingö in Sweden. 1/ km²2/ Population per km² Gallery Some places in th ...

, it is considered as a lake of great recreational value, especially popular among

ornithologists __NOTOC__ This is a list of ornithologists who have articles, in alphabetical order by surname. See also :Ornithologists. A * John Abbot – US * Clinton Gilbert Abbott – US * William Louis Abbott – US * Humayun Abdulali — India * Joseph ...

and frequently used in classes at the

located nearby. As the name implies, it used to be a

marsh In ecology, a marsh is a wetland that is dominated by herbaceous plants rather than by woody plants.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p More in genera ...

until construction works for the student apartments at Lappkärrsberget punctured a

subsoil Subsoil is the layer of soil under the topsoil on the surface of the ground. Like topsoil, it is composed of a variable mixture of small particles such as sand, silt and clay, but with a much lower percentage of organic matter and humus. The su ...

spring in the 1960s. Today, the lake empties into the strait

Lilla Värtan Lilla Värtan () or simply Värtan is a strait in Stockholm, Sweden. Separating mainland Stockholm from the island and municipality Lidingö, it stretches from Blockhusudden in the south to Stora Värtan in the north, and is joined by the Stocks ...

through a culvert and forms part of a proposed

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, funga, or features of geologic ...

in Norra Djurgården.

Catchment area

Most of the catchment area is composed of open fields and areas of

spruce A spruce is a tree of the genus ''Picea'' ( ), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ecosystem, boreal (taiga) regions of the Northern hemisphere. ''Picea'' ...

and

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, after flo ...

, with a single trafficked road passing west of the lake. Next to a group of nearby allotment-gardens is a

4-H 4-H is a U.S.-based network of youth organizations whose mission is "engaging youth to reach their fullest potential while advancing the field of youth development". Its name is a reference to the occurrence of the initial letter H four times ...

farmyard with horses and sheep.Vattenprogram, p 2.3

Environmental influence

Most of the inflow is believed to come from subsoil water with some contribution from

stormwater Stormwater, also written 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 lan ...

and snow-melting. Local land usage produces small amounts of nutrients and no conduits guides surface water to the lake. The lake is

alkali In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The a ...

and saliferous with high levels of

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

phosphorus Phosphorus is a chemical element; it has Chemical symbol, symbol P and atomic number 15. All elemental forms of phosphorus are highly Reactivity (chemistry), reactive and are therefore never found in nature. They can nevertheless be prepared ar ...

, and

phosphate Phosphates are the naturally occurring form of the element phosphorus. In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthop ...

, but low levels of inorganic

nitrogen Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...

. Notwithstanding various levels of

chlorophyll Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words (, "pale green") and (, "leaf"). Chlorophyll allows plants to absorb energy ...

, water transparency exceeds the depth of the lake and pH is reported as constant.

Flora and fauna

In the mid-1980s, isolated occurrences of rigid hornwort had established in the lake, and, by the mid-1990s, abundant quantities of other

aquatic plant Aquatic plants, also referred to as hydrophytes, are vascular plants and Non-vascular plant, non-vascular plants that have adapted to live in aquatic ecosystem, aquatic environments (marine ecosystem, saltwater or freshwater ecosystem, freshwater ...

s such as ivy duckweed and the

liverwort Liverworts are a group of non-vascular land plants forming the division Marchantiophyta (). They may also be referred to as hepatics. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry ...

'' Riccia fluitans'', were reported along open edges of the lake. During that decade, submarine vegetation covered the entire lake bed which greatly cleared up the lake. In the mid-1980s, the only fauna reported was sparse occurrences of

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e and non-biting midges. Within ten years, however, the fauna had evolved considerably, probably due to the rich vegetation, to include

Oligochaeta Oligochaeta () is a subclass of soft-bodied animals in the phylum Annelida, which is made up of many types of aquatic and terrestrial worms, including all of the various earthworms. Specifically, oligochaetes comprise the terrestrial megadril ...

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

s, and

dragonfly A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threat ...

larvae and today also the dragonfly species Aeshna osiliensis, common winter damselfly, and several others.Vattenprogram, p 2.3-2.6 The only fish in the lake is

crucian carp The crucian carp (''Carassius carassius'') is a medium-sized member of the common carp family Cyprinidae. It occurs widely in northern European regions. Its name derives from the Low German ''karusse'' or ''karutze'', possibly from Medieval Lat ...

, probably introduced in the early 1980s. Attempts have been made to reduce the population with various results. In the mid-1970 a colony of

black-headed gull The black-headed gull (''Chroicocephalus ridibundus'') is a small gull that breeds in much of the Palearctic in Europe and Asia, and also locally in smaller numbers in coastal eastern Canada. Most of the population is migratory and winters fu ...

s together with

Slavonian grebe The horned grebe or Slavonian grebe (''Podiceps auritus'') is a relatively small and threatened species of waterbird in the family Podicipedidae. There are two subspecies, ''P. a. auritus'' (Slavonian grebe), which breeds in Eurasia, and ' ...

mallard The mallard () or wild duck (''Anas platyrhynchos'') is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa. It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Arge ...

little grebe The little grebe (''Tachybaptus ruficollis''), also known as dabchick, is a member of the grebe family of water birds. The genus name is from Ancient Greek ''takhus'' "fast" and ''bapto'' "to sink under". The specific ''ruficollis'' is from Latin ...

, and

gadwall The gadwall (''Mareca strepera'') is a common and widespread dabbling duck in the family Anatidae. Taxonomy The gadwall was first described by Carl Linnaeus in his landmark 1758 10th edition of ''Systema Naturae''. DNA studies have shown th ...

. The black-headed gull is a key species, offering protection to other species, and has now abandoned the lake which is, however, still considered as of great importance to bird life with several species still breeding there. Several protected species of

amphibian Amphibians are ectothermic, anamniote, anamniotic, tetrapod, four-limbed vertebrate animals that constitute the class (biology), class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all Tetrapod, tetrapods, but excl ...

s can be seen by the lake, including

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 or simply the frog, is a semi ...

common toad The common toad, European toad, or in Anglophone parts of Europe, simply the toad (''Bufo bufo'', from Latin ''bufo'' "toad"), is a toad found throughout most of Europe (with the exception of Ireland, Iceland, parts of Scandinavia, and some List ...

moor frog The moor frog (''Rana arvalis'') is a slim, reddish-brown, semiaquatic amphibian native to Europe and Asia. Moor frogs are known for their ability to freeze solid and survive thawing. The frog makes use of various cryoprotectants i.e. Antifreeze ...

, and

smooth newt The smooth newt, European newt, northern smooth newt or common newt (''Lissotriton vulgaris'') is a species of newt. It is widespread in Europe and parts of Asia, and has been introduced species, introduced into Australia. Individuals are brown ...

Visiting

Both the lake and the surrounding national park is easily accessible by metro, bus, bicycle, or by foot. The nearest metro station is Universitetet and bus 50 stops nearby.

Notes

References

* *

External links

* {{DEFAULTSORT:Lappkarret Geography of Stockholm Lakes of Stockholm County Lakes in Djurgården