Lake Kasumigaura
Encyclopedia
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, located 60 km to the north-east of Tōkyō
Tokyo
, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...
. Lake Kasumigaura is actually the name given to a group of contiguous lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
s, which includes the main lake, Nishiura (西浦), and two smaller lakes, Kitaura (北浦）and Sotonasakaura (外浪逆浦), and also encompasses the rivers connecting them. About 45% of the land surrounding the lake is natural landscape and 43.5% is agricultural land.
History
The lakes of Kasumigaura once formed a deep marine bayBay
A bay is an area of water mostly surrounded by land. Bays generally have calmer waters than the surrounding sea, due to the surrounding land blocking some waves and often reducing winds. Bays also exist as an inlet in a lake or pond. A large bay may be called a gulf, a sea, a sound, or a bight...
, but have since been cut off from the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
by the sedimentation of adjacent rivers and the progress of tectonic subsidence since the late tertiary period. This lake was famous for its traditional fishery during the Edo period
Edo period
The , or , is a division of Japanese history which was ruled by the shoguns of the Tokugawa family, running from 1603 to 1868. The political entity of this period was the Tokugawa shogunate....
. But today, fishing production has drastically decreased due to water quality deterioration that was partially caused by the closure of the tide gate in 1963 for purposes of desalination.
Use
Today, Lake Kasumigaura is used for fishingFishing
Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....
, irrigation
Irrigation
Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
, tourism
Tourism
Tourism is travel for recreational, leisure or business purposes. The World Tourism Organization defines tourists as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes".Tourism has become a...
, recreation
Recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure and are considered to be "fun"...
, and for consumption
Consumption (economics)
Consumption is a common concept in economics, and gives rise to derived concepts such as consumer debt. Generally, consumption is defined in part by comparison to production. But the precise definition can vary because different schools of economists define production quite differently...
by the surrounding public and local industry.
A variety of fish can be caught from the waters of Lake Kasumigaura, including Smelt, Japanese Icefish
Icefish
Icefish may mean:* Notothenioidei, a suborder of mostly bottom-dwelling fish of the Southern Ocean* Salangidae, a family of smaller freshwater or anadromous fishes, most often found in East Asia and the northwestern Pacific Ocean...
, Crucian carp
Crucian carp
The crucian carp is a member of the family Cyprinidae, which includes many other fish, such as the common carp, or the smaller minnows. They inhabit lakes, ponds, and slow-moving rivers throughout Europe and Asia. The crucian is a medium-sized cyprinid, which rarely exceeds a weight of over 3.3...
, Goby
Goby
The gobies form the family Gobiidae, which is one of the largest families of fish, with more than 2,000 species in more than 200 genera. Most are relatively small, typically less than 10 cm in length...
, Japanese Eel and River Prawn
Freshwater prawn farm
A freshwater prawn farm is an aquaculture business designed to raise and produce freshwater prawn or shrimp for human consumption. Freshwater prawn farming shares many characteristics with, and many of the same problems as, marine shrimp farming...
. The most popular catch is cultivated carp, followed by smelt and goby. Another cultivated treasure from Lake Kasumigaura is the beautiful Kasumi freshwater pearl
Pearl
A pearl is a hard object produced within the soft tissue of a living shelled mollusk. Just like the shell of a mollusk, a pearl is made up of calcium carbonate in minute crystalline form, which has been deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other...
s. They were known for their high luster and rosy hues, which is the result of a four-year cultivation period. However, in 2006, cultivation was discontinued as cheap freshwater pearls from China proved too difficult to compete against.
The water from Lake Kasumigaura has long been used for the irrigation of paddy field
Paddy field
A paddy field is a flooded parcel of arable land used for growing rice and other semiaquatic crops. Paddy fields are a typical feature of rice farming in east, south and southeast Asia. Paddies can be built into steep hillsides as terraces and adjacent to depressed or steeply sloped features such...
s in the surrounding alluvial plain
Alluvial plain
An alluvial plain is a relatively flat landform created by the deposition of sediment over a long period of time by one or more rivers coming from highland regions, from which alluvial soil forms...
and upland fields on diluvial terraces
Diluvium
Diluvium is a term in geology for superficial deposits formed by flood-like operations of water, and so contrasted with alluvium or alluvial deposits formed by slow and steady aqueous agencies...
covered by thick deposits of volcanic ash
Volcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...
. The primary crops
Crop (agriculture)
A crop is a non-animal species or variety that is grown to be harvested as food, livestock fodder, fuel or for any other economic purpose. Major world crops include maize , wheat, rice, soybeans, hay, potatoes and cotton. While the term "crop" most commonly refers to plants, it can also include...
are rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
and lotus root (a local speciality). Other crops include tomato
Tomato
The word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...
, cucumber
Cucumber
The cucumber is a widely cultivated plant in the gourd family Cucurbitaceae, which includes squash, and in the same genus as the muskmelon. The plant is a creeping vine which bears cylindrical edible fruit when ripe. There are three main varieties of cucumber: "slicing", "pickling", and...
, eggplant, watermelon
Watermelon
Watermelon is a vine-like flowering plant originally from southern Africa. Its fruit, which is also called watermelon, is a special kind referred to by botanists as a pepo, a berry which has a thick rind and fleshy center...
, corn
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...
, edamame
Edamame
or Edamame bean is a preparation of immature soybeans in the pod commonly found in Japan, China, and Hawaii. The pods are boiled in water together with condiments such as salt, and served whole....
, sweet potato
Sweet potato
The sweet potato is a dicotyledonous plant that belongs to the family Convolvulaceae. Its large, starchy, sweet-tasting, tuberous roots are an important root vegetable. The young leaves and shoots are sometimes eaten as greens. Of the approximately 50 genera and more than 1,000 species of...
, kabocha
Kabocha
Kabocha is a Japanese variety of winter squash. The word kabocha has come to mean a general type of winter squash to many English-speaking growers and buyers. In some cultures it is revered as an aphrodisiac....
, daikon
Daikon
Daikon , Raphanus sativus var. longipinnatus, also called White Radish, Japanese radish, Oriental radish, Chinese radish, lo bok and Mooli , is a mild flavoured, very large, white East Asian radish...
and peanut
Peanut
The peanut, or groundnut , is a species in the legume or "bean" family , so it is not a nut. The peanut was probably first cultivated in the valleys of Peru. It is an annual herbaceous plant growing tall...
.
Many tourists come to the lake in the summer to view the unique ’’hobikibune’’ (帆引き船)
sail
Sail
A sail is any type of surface intended to move a vessel, vehicle or rotor by being placed in a wind—in essence a propulsion wing. Sails are used in sailing.-History of sails:...
ed fishing boats which are unique to Lake Kasumigaura. The Suigo aquapark, located in Tsuchiura city
Tsuchiura, Ibaraki
is a city located in Ibaraki prefecture, in Japan. It is situated along the western shores of Lake Kasumigaura, the second largest lake in Japan. Tokyo city lies about 60 km to the south, and Tsukuba science city borders Tsuchiura to the west.-Demographics:...
, is popular during the hottest months. Whereas the windmill
Windmill
A windmill is a machine which converts the energy of wind into rotational energy by means of vanes called sails or blades. Originally windmills were developed for milling grain for food production. In the course of history the windmill was adapted to many other industrial uses. An important...
of Kasumigaura comprehensive park is a popular site along the shores of the lake throughout the year, but especially in the spring when the tulip
Tulip
The tulip is a perennial, bulbous plant with showy flowers in the genus Tulipa, which comprises 109 species and belongs to the family Liliaceae. The genus's native range extends from as far west as Southern Europe, North Africa, Anatolia, and Iran to the Northwest of China. The tulip's centre of...
s are flowering.
The lake is also a recreation hotspot. Sport fishing enthusiasts and anglers
Angling
Angling is a method of fishing by means of an "angle" . The hook is usually attached to a fishing line and the line is often attached to a fishing rod. Fishing rods are usually fitted with a fishing reel that functions as a mechanism for storing, retrieving and paying out the line. The hook itself...
can be found close to shore
Shore
A shore or shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In Physical Oceanography a shore is the wider fringe that is geologically modified by the action of the body of water past and present, while the beach is at the edge of the shore,...
and around the river mouths surrounding the lake. Recreational boats, such as yachts, power boats, sail boats and personal watercraft, are regularly enjoyed on warm weekends around the lake. The wide surrounding wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s are wonderful for birdwatching
Birdwatching
Birdwatching or birding is the observation of birds as a recreational activity. It can be done with the naked eye, through a visual enhancement device like binoculars and telescopes, or by listening for bird sounds. Birding often involves a significant auditory component, as many bird species are...
, as large numbers of water fowl can be observed, primarily during the wintering period. Japanese Cormorant
Japanese Cormorant
The Japanese Cormorant , also known as Temminck's Cormorant, is a cormorant native to East Asia. It lives from Taiwan north through Korea and Japan to the Russian Far East....
, Bewick’s swan, little egret
Little Egret
The Little Egret is a small white heron. It is the Old World counterpart to the very similar New World Snowy Egret.-Subspecies:Depending on authority, two or three subspecies of Little Egret are currently accepted....
, gray heron, mallard
Mallard
The Mallard , or Wild Duck , is a dabbling duck which breeds throughout the temperate and subtropical Americas, Europe, Asia, and North Africa, and has been introduced to New Zealand and Australia....
, Eurasian wigeon, green heron
Green Heron
The Green Heron is a small heron of North and Central America. It was long considered conspecific with its sister species the Striated Heron , and together they were called "Green-backed Heron"...
, sharp-tailed sandpiper
Sharp-tailed Sandpiper
The Sharp-tailed Sandpiper, Calidris acuminata is a small wader.- Taxonomy :More recently, a review of new data has indicated that this bird should perhaps better be placed into the genus Philomachus- as P...
, bush warbler
Bush warbler
Bush-warblers are small insectivorous songbirds belonging to the genera Cettia and Bradypterus. They were formerly placed in the "wastebin" Old World warbler family...
, wood sandpiper
Wood Sandpiper
The Wood Sandpiper, Tringa glareola, is a small wader. This Eurasian species is the smallest of the shanks, which are mid-sized long-legged waders of the family Scolopacidae.- Description and systematics :...
, Japanese marsh warbler
Marsh Warbler
The Marsh Warbler, Acrocephalus palustris, is an Old World warbler currently classified in the family Acrocephalidae. It breeds in temperate Europe and western Asia and winters mainly in south east Africa...
, Japanese reed bunting
Reed Bunting
The Reed Bunting, Emberiza schoeniclus, is a passerine bird in the bunting family Emberizidae, a group now separated by most modern authors from the finches, Fringillidae....
, and the Eurasian coot are a few of the birds observable around the lake.
Lake Kasumigaura provides over 60 tons of water per second, of which the most goes to agriculture (83%). The rest is provided to local industry (13%) and public (4%) in the prefectures
Prefectures of Japan
The prefectures of Japan are the country's 47 subnational jurisdictions: one "metropolis" , Tokyo; one "circuit" , Hokkaidō; two urban prefectures , Osaka and Kyoto; and 43 other prefectures . In Japanese, they are commonly referred to as...
of Ibaraki
Ibaraki Prefecture
is a prefecture of Japan, located in the Kantō region on the main island of Honshu. The capital is Mito.-History:Ibaraki Prefecture was previously known as Hitachi Province...
, Chiba
Chiba Prefecture
is a prefecture of Japan located in the Kantō region and the Greater Tokyo Area. Its capital is Chiba City.- History :Chiba Prefecture was established on June 15, 1873 with the merger of Kisarazu Prefecture and Inba Prefecture...
and Tōkyō.
Challenges
EutrophicationEutrophication
Eutrophication or more precisely hypertrophication, is the movement of a body of water′s trophic status in the direction of increasing plant biomass, by the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage, to an aquatic system...
is a serious problem for Lake Kasumigaura. Legislation was enacted in 1982 to help prevent it, including a ban on the use and sale of phosphate-containing synthetic detergent
Detergent
A detergent is a surfactant or a mixture of surfactants with "cleaning properties in dilute solutions." In common usage, "detergent" refers to alkylbenzenesulfonates, a family of compounds that are similar to soap but are less affected by hard water...
s, and the control of nitrogen and phosphorus contents in the effluent
Effluent
Effluent is an outflowing of water or gas from a natural body of water, or from a human-made structure.Effluent is defined by the United States Environmental Protection Agency as “wastewater - treated or untreated - that flows out of a treatment plant, sewer, or industrial outfall. Generally refers...
from factories.
In order to help maintain the lake, dredging work is being carried out around the lake and at the estuaries of main inflowing rivers, such as Sakura river (桜川).