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59-669: Centro de Conservación Cetacea (CCC) is a Chilean non-governmental and non-profit organization that actively and effectively works on the conservation of marine mammals and their aquatic ecosystems in Chilean waters. The goals in support of this mission are: Since 2001, Centro de Conservacion Cetacea has conducted national marine conservation projects, including a wide range of areas like scientific research, public education, coastal community development and strengthening of marine conservation policies: “CITES CHILE 2002, Our Opportunity to Protect Life” , that reached over 140 thousand people of all

118-594: A combination of these sources. They were designed to retain the water, while at the same time letting some water seep away to feed the local aquifers . A defining feature of a pond is the presence of standing water which provides habitat for a biological community commonly referred to as pond life . Because of this, many ponds and lakes contain large numbers of endemic species that have gone through adaptive radiation to become specialized to their preferred habitat. Familiar examples might include water lilies and other aquatic plants, frogs , turtles , and fish. Often,

177-536: A deep mixing layer occurs. Autumn turnover results in isothermal lakes with high levels of dissolved oxygen as the water reaches an average colder temperature. Finally, winter stratification occurs inversely to summer stratification as surface ice begins to form yet again. This ice cover remains until solar radiation and convection return in the spring. Due to this constant change in vertical zonation, seasonal stratification causes habitats to grow and shrink accordingly. Certain species are bound to these distinct layers of

236-440: A major higher tropic level consumer, as these ponds frequently dry up. The absence of fish is a very important characteristic of these ponds since it prevents long chained biotic interactions from establishing. Ponds without these competitive predation pressures provides breeding locations and safe havens for endangered or migrating species. Hence, introducing fish to a pond can have seriously detrimental consequences. In some parts of

295-984: A major predator upon amphibian larvae, ponds that dry up each year, thereby killing resident fish, provide important refugia for amphibian breeding. Ponds that dry up completely each year are often known as vernal pools . Some ponds are produced by animal activity, including alligator holes and beaver ponds , and these add important diversity to landscapes. Ponds are frequently man made or expanded beyond their original depths and bounds by anthropogenic causes. Apart from their role as highly biodiverse, fundamentally natural, freshwater ecosystems ponds have had, and still have, many uses, including providing water for agriculture , livestock and communities, aiding in habitat restoration, serving as breeding grounds for local and migrating species, decorative components of landscape architecture , flood control basins, general urbanization, interception basins for pollutants and sources and sinks of greenhouse gases . The technical distinction between

354-663: A pond and a lake has not been universally standardized. Limnologists and freshwater biologists have proposed formal definitions for pond , in part to include 'bodies of water where light penetrates to the bottom of the waterbody', 'bodies of water shallow enough for rooted water plants to grow throughout', and 'bodies of water which lack wave action on the shoreline'. Each of these definitions are difficult to measure or verify in practice and are of limited practical use, and are mostly not now used. Accordingly, some organizations and researchers have settled on technical definitions of pond and lake that rely on size alone. Some regions of

413-590: A project that has been conducted since 2003 with the official support of the Chilean Navy and the cooperation of leading right whale conservation organizations from Argentina, Brazil and Uruguay. In 2008 the southeast Pacific population of this species was classified as critically endangered by the International Union for Conservation of Nature (IUCN) and the Chilean Navy granted maximum level of protection to

472-589: A regular yearly process in the same matter as larger lakes if they are deep enough and/or protected from the wind. Abiotic factors such as UV radiation, general temperature, wind speed, water density, and even size, all have important roles to play when it comes to the seasonal effects on lakes and ponds. Spring overturn, summer stratification, autumn turnover, and an inverse winter stratification, ponds adjust their stratification or their vertical zonation of temperature due to these influences. These environmental factors affect pond circulation and temperature gradients within

531-1195: A result of physical, chemical or biological alterations to the environment. Physical alterations include changes in water temperature, water flow and light availability. Chemical alterations include changes in the loading rates of biostimulatory nutrients, oxygen-consuming materials, and toxins. Biological alterations include over-harvesting of commercial species and the introduction of exotic species. Human populations can impose excessive stresses on aquatic ecosystems. Climate change driven by anthropogenic activities can harm aquatic ecosystems by disrupting current distribution patterns of plants and animals. It has negatively impacted deep sea biodiversity, coastal fish diversity, crustaceans, coral reefs, and other biotic components of these ecosystems. Human-made aquatic ecosystems, such as ditches, aquaculture ponds, and irrigation channels, may also cause harm to naturally occurring ecosystems by trading off biodiversity with their intended purposes. For instance, ditches are primarily used for drainage, but their presence also negatively affects biodiversity. There are many examples of excessive stresses with negative consequences. The environmental history of

590-449: A result, breakdown and release of nitrogen gases from these organic materials such as N 2 O does not occur and thus, not added to our atmosphere. This process is also used with regular denitrification in anoxic layer of ponds. However, not all ponds have the ability to become sinks for greenhouse gasses . Most ponds experience eutrophication where faced with excessive nutrient input from fertilizers and runoff. This over-nitrifies

649-401: Is a small, still, land-based body of water formed by pooling inside a depression , either naturally or artificially . A pond is smaller than a lake and there are no official criteria distinguishing the two, although defining a pond to be less than 5 hectares (12 acres) in area, less than 5 metres (16 ft) in depth and with less than 30% with emergent vegetation helps in distinguishing

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708-498: Is crucial that aquatic ecosystems are reliably self-maintained, as they also provide habitats for species that reside in them. In addition to environmental functions, aquatic ecosystems are also used for human recreation, and are very important to the tourism industry, especially in coastal regions. They are also used for religious purposes, such as the worshipping of the Jordan River by Christians, and educational purposes, such as

767-478: Is fatal to many kinds of anaerobic bacteria. Nutrient levels are important in controlling the abundance of many species of algae. The relative abundance of nitrogen and phosphorus can in effect determine which species of algae come to dominate. Algae are a very important source of food for aquatic life, but at the same time, if they become over-abundant, they can cause declines in fish when they decay. Similar over-abundance of algae in coastal environments such as

826-584: Is no universally recognized standard for the maximum size of a pond. The international Ramsar wetland convention sets the upper limit for pond size as 8  hectares (80,000  m ; 20  acres ). Researchers for the British charity Pond Conservation (now called Freshwater Habitats Trust) have defined a pond to be 'a man-made or natural waterbody that is between 1 m (0.00010 hectares; 0.00025 acres) and 20,000 m (2.0 hectares; 4.9 acres) in area, which holds water for four months of

885-466: Is reached. As temperatures increase through the summer, thermal stratification takes place. Summer stratification allows for the epilimnion to be mixed by winds, keeping a consistent warm temperature throughout this zone. Here, photosynthesis and primary production flourishes. However, those species that need cooler water with higher dissolved oxygen concentrations will favor the lower metalimnion or hypolimnion. Air temperature drops as fall approaches and

944-464: Is the Prairie Pothole Region of North America. When glaciers retreat, they may leave behind uneven ground due to bedrock elastic rebound and sediment outwash plains. These areas may develop depressions that can fill up with excess precipitation or seeping ground water, forming a small pond. Kettle lakes and ponds are formed when ice breaks off from a larger glacier, is eventually buried by

1003-539: The Amazon . Some ponds are solely created by animals species such as beavers , bison , alligators and other crocodilians through damning and nest excavation respectively. In landscapes with organic soils , local fires can create depressions during periods of drought. These have the tendency to fill up with small amounts of precipitation until normal water levels return, turning these isolated ponds into open water. Manmade ponds are those created by human intervention for

1062-616: The Common Carp that eat native water plants or Northern Snakeheads that attack breeding amphibians, aquatic snails that carry infectious parasites that kill other species, and even rapid spreading aquatic plants like Hydrilla and Duckweed that can restrict water flow and cause overbank flooding. Ponds, depending on their orientation and size, can spread their wetland habitats into the local riparian zones or watershed boundaries. Gentle slopes of land into ponds provides an expanse of habitat for wetland plants and wet meadows to expand beyond

1121-645: The Great Lakes of North America illustrates this problem, particularly how multiple stresses, such as water pollution , over-harvesting and invasive species can combine. The Norfolk Broadlands in England illustrate similar decline with pollution and invasive species. Lake Pontchartrain along the Gulf of Mexico illustrates the negative effects of different stresses including levee construction, logging of swamps, invasive species and salt water intrusion . Pond A pond

1180-641: The ecology of ponds from those of lakes and wetlands . Ponds can be created by a wide variety of natural processes (e.g. on floodplains as cutoff river channels, by glacial processes, by peatland formation, in coastal dune systems, by beavers ), or they can simply be isolated depressions (such as a kettle hole, vernal pool , prairie pothole , or simply natural undulations in undrained land) filled by runoff, groundwater, or precipitation, or all three of these. They can be further divided into four zones: vegetation zone, open water, bottom mud and surface film. The size and depth of ponds often varies greatly with

1239-555: The flux of these dissolved compounds. However, manmade farm ponds are becoming significant sinks for gas mitigation and the fight against climate change . These agriculture runoff ponds receive high pH level water from surrounding soils. Highly acidic drainage ponds act as catalysis for excess CO 2 (carbon dioxide) to be converted into forms of carbon that can easily be stored in sediments. When these new drainage ponds are constructed, concentrations of bacteria that normally break down dead organic matter, such as algae, are low. As

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1298-552: The salmon farming industry. “Chile 2008, A Whale Sanctuary” , that was conducted during eight months in conjunction with Centro Ecoceanos and the National Confederation of Artisan Fishers of Chile . As a result, the sanctuary was achieved in only eight months with the unanimous support by the Chilean Congress of the bill/law that bans all types of whaling operations in Chilean jurisdictional waters (EEZ) and sets

1357-445: The Gulf of Mexico produces, upon decay, a hypoxic region of water known as a dead zone . The salinity of the water body is also a determining factor in the kinds of species found in the water body. Organisms in marine ecosystems tolerate salinity, while many freshwater organisms are intolerant of salt. The degree of salinity in an estuary or delta is an important control upon the type of wetland (fresh, intermediate, or brackish), and

1416-503: The United States define a pond as a body of water with a surface area of less than 10 acres (4.0 ha). Minnesota , known as the "land of 10,000 lakes", is commonly said to distinguish lakes from ponds, bogs and other water features by this definition, but also says that a lake is distinguished primarily by wave action reaching the shore. Even among organizations and researchers who distinguish lakes from ponds by size alone, there

1475-450: The associated animal species. Dams built upstream may reduce spring flooding, and reduce sediment accretion, and may therefore lead to saltwater intrusion in coastal wetlands. Freshwater used for irrigation purposes often absorbs levels of salt that are harmful to freshwater organisms. The health of an aquatic ecosystem is degraded when the ecosystem's ability to absorb a stress has been exceeded. A stress on an aquatic ecosystem can be

1534-869: The basis for consolidating a national marine conservation policy. This is the first marine protection policy adopted in Chilean history and the most important measure taken until date in the country for the effective conservation of cetacean species and their marine environment. Aquatic ecosystems An aquatic ecosystem is an ecosystem found in and around a body of water , in contrast to land-based terrestrial ecosystems . Aquatic ecosystems contain communities of organisms — aquatic life —that are dependent on each other and on their environment. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems . Freshwater ecosystems may be lentic (slow moving water, including pools , ponds , and lakes ); lotic (faster moving water, for example streams and rivers ); and wetlands (areas where

1593-556: The best conditions for wildlife, but they help protect water quality from sources in the surrounding landscapes. It is also beneficial to allow water levels to fall each year during drier periods in order to re-establish these gentile shorelines. In landscapes where ponds are artificially constructed, they are done so to provide wildlife viewing and conservation opportunities, to treat wastewater, for sequestration and pollution containment, or for simply aesthetic purposes. For natural pond conservation and development, one way to stimulate this

1652-518: The case of Crystal Lake shows, marketing purposes can sometimes be the driving factor behind the categorization. In practice, a body of water is called a pond or a lake on an individual basis, as conventions change from place to place and over time. In origin, a pond is a variant form of the word pound, meaning a confining enclosure. In earlier times, ponds were artificial and utilitarian, as stew ponds , mill ponds and so on. The significance of this feature seems, in some cases, to have been lost when

1711-582: The country with an educational exhibit of life size inflatable whales and sharks. As a result, the government of Chile strongly opposed proposals oriented to down list whale species from Appendix I and supported proposals oriented to include whale and basking sharks in CITES Appendix II, during the 12th Conference of the Parties of CITES conducted in Santiago de Chile. “ Southern Right Whale Project/Chile” ,

1770-504: The entire margin of the pond is fringed by wetland , and these wetlands support the aquatic food web , provide shelter for wildlife, and stabilize the shore of the pond. This margin is also known as the littoral zone and contains much of the photosynthetic algae and plants of this ecosystem called macrophytes . Other photosynthetic organisms such as phytoplankton (suspended algae) and periphytons (organisms including cyanobacteria , detritus , and other microbes ) thrive here and stand as

1829-480: The fields of environmental science, chemistry, aquatic biology, and limnology. Some ponds are the life blood of many small villages in arid countries such as those in sub-Saharan Africa where bathing, sanitation, fishing, socialization, and rituals are held. In the Indian subcontinent , Hindu temple monks care for sacred ponds used for religious practices and bathing pilgrims alike. In Europe during medieval times, it

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1888-545: The ground which collects and retains a sufficient amount of water can be considered a pond, and such, can be formed by a variety of geological , ecological , and human terraforming events. Natural ponds are those caused by environmental occurrences. These can vary from glacial, volcanic, fluvial, or even tectonic events. Since the Pleistocene epoch, glacial processes have created most of the Northern hemispheric ponds; an example

1947-429: The important abiotic environmental factors of aquatic ecosystems include substrate type, water depth, nutrient levels, temperature, salinity, and flow. It is often difficult to determine the relative importance of these factors without rather large experiments. There may be complicated feedback loops. For example, sediment may determine the presence of aquatic plants, but aquatic plants may also trap sediment, and add to

2006-539: The limitation of the pond. However, the construction of retaining walls, lawns, and other urbanized developments can severely degrade the range of pond habitats and the longevity of the pond itself. Roads and highways act in the same manor, but they also interfere with amphibians and turtles that migrate to and from ponds as part of their annual breeding cycle and should be kept as far away from established ponds as possible. Because of these factors, gently sloping shorelines with broad expanses of wetland plants not only provide

2065-516: The littoral zone and the limnetic zone. The open water limnetic zone may allow algae to grow as sunlight still penetrates here. These algae may support yet another food web that includes aquatic insects and other small fish species. A pond, therefore, may have combinations of three different food webs, one based on larger plants, one based upon decayed plants, and one based upon algae and their specific upper trophic level consumers and predators. Hence, ponds often have many different animal species using

2124-555: The official support of the Chilean Navy, the Ministry of Foreign Affairs and the Ministry of Education of Chile. The project has also identified the area with the highest sighting rate of blue whales in the Southern Hemisphere (northwestern Chiloé Island ) and has raised international awareness regarding the health status of this blue whale population by describing skinny blue whales and skin lesions associated to coastal pollution from

2183-422: The organic compounds in their bodies as energy sources and as raw materials to create their own biomass . Euryhaline organisms are salt tolerant and can survive in marine ecosystems, while stenohaline or salt intolerant species can only live in freshwater environments. An ecosystem is composed of biotic communities that are structured by biological interactions and abiotic environmental factors. Some of

2242-514: The pond water and results in mass algae blooms and local fish kills . Some farm ponds are not used for runoff control but rather for livestock like cattle or buffalo as watering and bathing holes. As mentioned in the use section, ponds are important hotspots for biodiversity. Sometimes this becomes an issue with invasive or introduced species that disrupt pond ecosystem dynamics such as food-web structure, niche partitioning, and guild assignments. This varies from introduced fish species such as

2301-514: The ponds, the shape, the presence of visiting large mammals, the composition of any fish communities and salinity can all affect the types of plant and animal communities present. Food webs are based both on free-floating algae and upon aquatic plants. There is usually a diverse array of aquatic life, with a few examples including algae, snails , fish, beetles , water bugs , frogs , turtles , otters , and muskrats . Top predators may include large fish, herons , or alligators . Since fish are

2360-409: The primary producers of pond food webs. Some grazing animals like geese and muskrats consume the wetland plants directly as a source of food. In many other cases, pond plants will decay in the water. Many invertebrates and herbivorous zooplankton then feed on the decaying plants, and these lower trophic level organisms provide food for wetland species including fish, dragonflies , and herons both in

2419-476: The relative importance of competition, mutualism or predation. There are a growing number of cases where predation by coastal herbivores including snails, geese and mammals appears to be a dominant biotic factor. Autotrophic organisms are producers that generate organic compounds from inorganic material. Algae use solar energy to generate biomass from carbon dioxide and are possibly the most important autotrophic organisms in aquatic environments. The more shallow

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2478-857: The river bed's gradient or by the velocity of the current. Faster moving turbulent water typically contains greater concentrations of dissolved oxygen , which supports greater biodiversity than the slow-moving water of pools. These distinctions form the basis for the division of rivers into upland and lowland rivers. Aquatic ecosystems perform many important environmental functions. For example, they recycle nutrients , purify water, attenuate floods, recharge ground water and provide habitats for wildlife. The biota of an aquatic ecosystem contribute to its self-purification, most notably microorganisms, phytoplankton, higher plants, invertebrates, fish, bacteria, protists, aquatic fungi, and more. These organisms are actively involved in multiple self-purification processes, including organic matter destruction and water filtration. It

2537-1001: The sake of the local environment, industrial settings, or for recreational/ornamental use. Many ecosystems are linked by water and ponds have been found to hold a greater biodiversity of species than larger freshwater lakes or river systems. As such, ponds are habitats for many varieties of organisms including plants, amphibians , fish, reptiles , waterfowl , insects , and even some mammals . Ponds are used for breeding grounds for these species but also as shelter and even drinking/feeding locations for other wildlife. Aquaculture practices lean heavily on artificial ponds in order to grow and care for many different type of fish either for human consumption, research, species conservation or recreational sport. In agriculture practices, treatment ponds can be created to reduce nutrient runoff from reaching local streams or groundwater storages. Pollutants that enter ponds can often be mitigated by natural sedimentation and other biological and chemical activities within

2596-468: The sediment through peat. The amount of dissolved oxygen in a water body is frequently the key substance in determining the extent and kinds of organic life in the water body. Fish need dissolved oxygen to survive, although their tolerance to low oxygen varies among species; in extreme cases of low oxygen, some fish even resort to air gulping. Plants often have to produce aerenchyma , while the shape and size of leaves may also be altered. Conversely, oxygen

2655-559: The soil is saturated or inundated for at least part of the time). River ecosystems are flowing waters that drain the landscape, and include the biotic (living) interactions amongst plants, animals and micro-organisms, as well as abiotic (nonliving) physical and chemical interactions of its many parts. River ecosystems are part of larger watershed networks or catchments, where smaller headwater streams drain into mid-size streams, which progressively drain into larger river networks. The major zones in river ecosystems are determined by

2714-416: The species. “National Marine Mammal Sighting Network” , it has work effectively thanks to the support and cooperation of the Chilean Navy and more than 500 members that actively participate in recording of cetacean sightings and stranding events along the Chilean coast. Alfaguara project . It has consolidated as a scientific and coastal sustainable development project of national interest by receiving

2773-799: The surrounding glacial till, and over time melts. Orogenies and other tectonic uplifting events have created some of the oldest lakes and ponds on the globe. These indentions have the tendency to quickly fill with groundwater if they occur below the local water table. Other tectonic rifts or depressions can fill with precipitation, local mountain runoff, or be fed by mountain streams. Volcanic activity can also lead to lake and pond formation through collapsed lava tubes or volcanic cones. Natural floodplains along rivers, as well as landscapes that contain many depressions, may experience spring/rainy season flooding and snow melt. Temporary or vernal ponds are created this way and are important for breeding fish, insects, and amphibians, particularly in large river systems like

2832-475: The terms is lochan , which may also apply to a large body of water such as a lake. In the South Western parts of North American, lakes or ponds that are temporary and often dried up for most parts of the year are called playas . These playas are simply shallow depressions in dry areas that may only fill with water on certain occasion like excess local drainage, groundwater seeping, or rain. Any depression in

2891-604: The time of year; many ponds are produced by spring flooding from rivers. Ponds are usually freshwater but may be brackish in nature. Saltwater pools, with a direct connection to the sea to maintain full salinity, may sometimes be called 'ponds' but these are normally regarded as part of the marine environment. They do not support fresh or brackish water-based organisms, and are rather tidal pools or lagoons . Ponds are typically shallow water bodies with varying abundances of aquatic plants and animals. Depth, seasonal water level variations, nutrient fluxes, amount of light reaching

2950-553: The usage of lakes for ecological study . The biotic characteristics are mainly determined by the organisms that occur. For example, wetland plants may produce dense canopies that cover large areas of sediment—or snails or geese may graze the vegetation leaving large mud flats. Aquatic environments have relatively low oxygen levels, forcing adaptation by the organisms found there. For example, many wetland plants must produce aerenchyma to carry oxygen to roots. Other biotic characteristics are more subtle and difficult to measure, such as

3009-460: The water column where they can thrive and survive with the best efficiency possible. For more information regarding seasonal thermal stratification of ponds and lakes, please look at " Lake Stratification ". Ponds provide not only environmental values, but practical benefits to society. One increasingly crucial benefit that ponds provide is their ability to act as greenhouse gas sinks. Most natural lakes and ponds are greenhouse gas sources and aid in

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3068-472: The water itself producing distant layers; the epilimnion , metalimnion , and hypolimnion . Each zone has varied traits that sustain or harm specific organisms and biotic interactions below the surface depending on the season. Winter surface ice begins to melt in the Spring. This allows the water column to begin mixing thanks to solar convection and wind velocity. As the pond mixes, an overall constant temperature

3127-743: The water, the greater the biomass contribution from rooted and floating vascular plants. These two sources combine to produce the extraordinary production of estuaries and wetlands, as this autotrophic biomass is converted into fish, birds, amphibians and other aquatic species. Chemosynthetic bacteria are found in benthic marine ecosystems. These organisms are able to feed on hydrogen sulfide in water that comes from volcanic vents . Great concentrations of animals that feed on these bacteria are found around volcanic vents. For example, there are giant tube worms ( Riftia pachyptila ) 1.5 m in length and clams ( Calyptogena magnifica ) 30 cm long. Heterotrophic organisms consume autotrophic organisms and use

3186-487: The water. As such, waste stabilization ponds are becoming popular low-cost methods for general wastewater treatment. They may also provide irrigation reservoirs for struggling farms during times of drought. As urbanization continues to spread, retention ponds are becoming more common in new housing developments. These ponds reduce the risk of flooding and erosion damage from excess storm water runoff in local communities. Experimental ponds are used to test hypotheses in

3245-489: The wide array of food sources though biotic interaction. They, therefore, provide an important source of biological diversity in landscapes. Opposite to long standing ponds are vernal ponds . These ponds dry up for part of the year and are so called because they are typically at their peak depth in the spring (the meaning of "vernal" comes form the Latin word for spring ). Naturally occurring vernal ponds do not usually have fish,

3304-515: The word was carried abroad with emigrants. However, some parts of New England contain "ponds" that are actually the size of a small lake when compared to other countries. In the United States, natural pools are often called ponds. Ponds for a specific purpose keep the adjective, such as "stock pond", used for watering livestock. The term is also used for temporary accumulation of water from surface runoff ( ponded water). There are various regional names for naturally occurring ponds. In Scotland, one of

3363-511: The world, such as California, the vernal ponds have rare and endangered plant species. On the coastal plain, they provide habitat for endangered frogs such as the Mississippi Gopher Frog . Often groups of ponds in a given landscape - so called 'pondscapes' - offer especially high biodiversity benefits compared to single ponds. A group of ponds provides a higher degree of habitat complexity and habitat connectivity. Many ponds undergo

3422-618: The year or more.' Other European biologists have set the upper size limit at 5 hectares (50,000 m ; 12 acres). In North America, even larger bodies of water have been called ponds; for example, Crystal Lake at 33 acres (130,000 m ; 13 ha), Walden Pond in Concord, Massachusetts at 61 acres (250,000 m ; 25 ha), and nearby Spot Pond at 340 acres (140 ha). There are numerous examples in other states, where bodies of water less than 10 acres (40,000 m ; 4.0 ha) are being called lakes. As

3481-508: Was typical for many monastery and castles (small, partly self-sufficient communities) to have fish ponds . These are still common in Europe and in East Asia (notably Japan), where koi may be kept or raised. In Nepal artificial ponds were essential elements of the ancient drinking water supply system . These ponds were fed with rainwater, water coming in through canals , their own springs, or

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