Fresh water is any occurring water except seawater and brackish water. Fresh water includes water in ice sheets, ice caps, icebergs, ponds, rivers and underground water called groundwater. Fresh water is characterized by having low concentrations of dissolved salts and other total dissolved solids. Though the term excludes seawater and brackish water, it does include mineral-rich waters such as chalybeate springs. Fresh water is not the same as potable water. Much of the earth's fresh water is unsuitable for drinking without some treatment. Fresh water can become polluted by human activities or due to occurring processes, such as erosion. Water is critical to the survival of all living organisms; some organisms can thrive on salt water, but the great majority of higher plants and most mammals need fresh water to live. Fresh water can be defined as water with less than 500 parts per million of dissolved salts. Other sources give higher upper salinity limits for e.g. 1000 ppm or 3000 ppm. Fresh water habitats are classified as either lentic systems, which are the stillwaters including ponds, lakes and mires.
There is, in addition, a zone which bridges between groundwater and lotic systems, the hyporheic zone, which underlies many larger rivers and can contain more water than is seen in the open channel. It may be in direct contact with the underlying underground water; the majority of fresh water on Earth is in ice caps. The source of all fresh water is precipitation from the atmosphere, in the form of mist and snow. Fresh water falling as mist, rain or snow contains materials dissolved from the atmosphere and material from the sea and land over which the rain bearing clouds have traveled. In industrialized areas rain is acidic because of dissolved oxides of sulfur and nitrogen formed from burning of fossil fuels in cars, factories and aircraft and from the atmospheric emissions of industry. In some cases this acid rain results in pollution of rivers. In coastal areas fresh water may contain significant concentrations of salts derived from the sea if windy conditions have lifted drops of seawater into the rain-bearing clouds.
This can give rise to elevated concentrations of sodium, chloride and sulfate as well as many other compounds in smaller concentrations. In desert areas, or areas with impoverished or dusty soils, rain-bearing winds can pick up sand and dust and this can be deposited elsewhere in precipitation and causing the freshwater flow to be measurably contaminated both by insoluble solids but by the soluble components of those soils. Significant quantities of iron may be transported in this way including the well-documented transfer of iron-rich rainfall falling in Brazil derived from sand-storms in the Sahara in north Africa. Saline water in oceans and saline groundwater make up about 97% of all the water on Earth. Only 2.5–2.75% is fresh water, including 1.75–2% frozen in glaciers and snow, 0.5–0.75% as fresh groundwater and soil moisture, less than 0.01% of it as surface water in lakes and rivers. Freshwater lakes contain about 87% of this fresh surface water, including 29% in the African Great Lakes, 22% in Lake Baikal in Russia, 21% in the North American Great Lakes, 14% in other lakes.
Swamps have most of the balance with only a small amount in rivers, most notably the Amazon River. The atmosphere contains 0.04% water. In areas with no fresh water on the ground surface, fresh water derived from precipitation may, because of its lower density, overlie saline ground water in lenses or layers. Most of the world's fresh water is frozen in ice sheets. Many areas suffer from lack of distribution such as deserts. Water is a critical issue for the survival of all living organisms; some can use salt water but many organisms including the great majority of higher plants and most mammals must have access to fresh water to live. Some terrestrial mammals desert rodents, appear to survive without drinking, but they do generate water through the metabolism of cereal seeds, they have mechanisms to conserve water to the maximum degree. Fresh water creates a hypotonic environment for aquatic organisms; this is problematic for some organisms with pervious skins or with gill membranes, whose cell membranes may burst if excess water is not excreted.
Some protists accomplish this using contractile vacuoles, while freshwater fish excrete excess water via the kidney. Although most aquatic organisms have a limited ability to regulate their osmotic balance and therefore can only live within a narrow range of salinity, diadromous fish have the ability to migrate between fresh water and saline water bodies. During these migrations they undergo changes to adapt to the surroundings of the changed salinities; the eel uses the hormone prolactin, while in salmon the hormone cortisol plays a key role during this process. Many sea birds have special glands at the base of the bill; the marine iguanas on the Galápagos Islands excrete excess salt through a nasal gland and they sneeze out a salty excretion. Freshwater molluscs include freshwater snails and freshwater bivalves. Freshwater crustaceans include crayfish. Freshwater biodiversity faces many threats; the World Wide Fund for Nature's Living Planet Index noted an 83% decline in the populations of freshwater vertebrates between 1970 and 2014.
These declines continue to outpace
A wetland is a distinct ecosystem, inundated by water, either permanently or seasonally, where oxygen-free processes prevail. The primary factor that distinguishes wetlands from other land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil. Wetlands play a number of functions, including water purification, water storage, processing of carbon and other nutrients, stabilization of shorelines, support of plants and animals. Wetlands are considered the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal life. Whether any individual wetland performs these functions, the degree to which it performs them, depends on characteristics of that wetland and the lands and waters near it. Methods for assessing these functions, wetland ecological health, general wetland condition have been developed in many regions and have contributed to wetland conservation by raising public awareness of the functions and the ecosystem services some wetlands provide.
Wetlands occur on every continent. The main wetland types are swamp, marsh and fen. Many peatlands are wetlands; the water in wetlands is either brackish, or saltwater. Wetlands can be non-tidal; the largest wetlands include the Amazon River basin, the West Siberian Plain, the Pantanal in South America, the Sundarbans in the Ganges-Brahmaputra delta. The UN Millennium Ecosystem Assessment determined that environmental degradation is more prominent within wetland systems than any other ecosystem on Earth. Constructed wetlands are used to treat municipal and industrial wastewater as well as stormwater runoff, they may play a role in water-sensitive urban design. A patch of land that develops pools of water after a rain storm would not be considered a "wetland" though the land is wet. Wetlands have unique characteristics: they are distinguished from other water bodies or landforms based on their water level and on the types of plants that live within them. Wetlands are characterized as having a water table that stands at or near the land surface for a long enough period each year to support aquatic plants.
A more concise definition is a community composed of hydric soil and hydrophytes. Wetlands have been described as ecotones, providing a transition between dry land and water bodies. Mitsch and Gosselink write that wetlands exist "...at the interface between terrestrial ecosystems and aquatic systems, making them inherently different from each other, yet dependent on both."In environmental decision-making, there are subsets of definitions that are agreed upon to make regulatory and policy decisions. A wetland is "an ecosystem that arises when inundation by water produces soils dominated by anaerobic and aerobic processes, which, in turn, forces the biota rooted plants, to adapt to flooding." There are four main kinds of wetlands – marsh, swamp and fen. Some experts recognize wet meadows and aquatic ecosystems as additional wetland types; the largest wetlands in the world include the swamp forests of the Amazon and the peatlands of Siberia. Under the Ramsar international wetland conservation treaty, wetlands are defined as follows: Article 1.1: "...wetlands are areas of marsh, peatland or water, whether natural or artificial, permanent or temporary, with water, static or flowing, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres."
Article 2.1: " may incorporate riparian and coastal zones adjacent to the wetlands, islands or bodies of marine water deeper than six metres at low tide lying within the wetlands." Although the general definition given above applies around the world, each county and region tends to have its own definition for legal purposes. In the United States, wetlands are defined as "those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, that under normal circumstances do support, a prevalence of vegetation adapted for life in saturated soil conditions. Wetlands include swamps, marshes and similar areas"; this definition has been used in the enforcement of the Clean Water Act. Some US states, such as Massachusetts and New York, have separate definitions that may differ from the federal government's. In the United States Code, the term wetland is defined "as land that has a predominance of hydric soils, is inundated or saturated by surface or groundwater at a frequency and duration sufficient to support a prevalence of hydrophytic vegetation adapted for life in saturated soil conditions and under normal circumstances supports a prevalence of such vegetation."
Related to this legal definitions, the term "normal circumstances" are conditions expected to occur during the wet portion of the growing season under normal climatic conditions, in the absence of significant disturbance. It is not uncommon for a wetland to be dry for long portions of the growing season. Wetlands can be dry during the dry season and abnormally dry periods during the wet season, but under normal environmental conditions the soils in a wetland will be saturated to the surface or inundated such that the soils become anaerobic, those conditions will persist through the wet portion of the growing season; the most important factor producing wetlands is flooding. The duration of flooding or prolonged soil saturation by groundwater determines whether the resulting wetland has aquatic, marsh or swamp vegetation
Rice is the seed of the grass species Oryza sativa or Oryza glaberrima. As a cereal grain, it is the most consumed staple food for a large part of the world's human population in Asia, it is the agricultural commodity with the third-highest worldwide production, after sugarcane and maize. Since sizable portions of sugarcane and maize crops are used for purposes other than human consumption, rice is the most important grain with regard to human nutrition and caloric intake, providing more than one-fifth of the calories consumed worldwide by humans. There are many varieties of rice and culinary preferences tend to vary regionally. Rice, a monocot, is grown as an annual plant, although in tropical areas it can survive as a perennial and can produce a ratoon crop for up to 30 years. Rice cultivation is well-suited to countries and regions with low labor costs and high rainfall, as it is labor-intensive to cultivate and requires ample water. However, rice can be grown anywhere on a steep hill or mountain area with the use of water-controlling terrace systems.
Although its parent species are native to Asia and certain parts of Africa, centuries of trade and exportation have made it commonplace in many cultures worldwide. The traditional method for cultivating rice is flooding the fields while, or after, setting the young seedlings; this simple method requires sound planning and servicing of the water damming and channeling, but reduces the growth of less robust weed and pest plants that have no submerged growth state, deters vermin. While flooding is not mandatory for the cultivation of rice, all other methods of irrigation require higher effort in weed and pest control during growth periods and a different approach for fertilizing the soil; the name wild rice is used for species of the genera Zizania and Porteresia, both wild and domesticated, although the term may be used for primitive or uncultivated varieties of Oryza. First used in English in the middle of the 13th century, the word "rice" derives from the Old French ris, which comes from the Italian riso, in turn from the Latin oriza, which derives from the Greek ὄρυζα.
The Greek word is the source of all European words. The origin of the Greek word is unclear, it is sometimes held to be from the Tamil word, or rather Old Tamil arici. However, Krishnamurti disagrees with the notion that Old Tamil arici is the source of the Greek term, proposes that it was borrowed from descendants of Proto-Dravidian *wariñci instead. Mayrhofer suggests that the immediate source of the Greek word is to be sought in Old Iranian words of the types *vrīz- or *vrinj-, but these are traced back to Indo-Aryan. P. T. Srinivasa Iyengar assumed that the Sanskrit vrīhí- is derived from the Tamil arici, while Ferdinand Kittel derived it from the Dravidian root variki; the rice plant can grow to 1–1.8 m tall more depending on the variety and soil fertility. It has long, slender leaves 50–100 cm long and 2–2.5 cm broad. The small wind-pollinated flowers are produced in a branched arching to pendulous inflorescence 30–50 cm long; the edible seed is a grain 5–12 mm long and 2–3 mm thick. The varieties of rice are classified as long-, medium-, short-grained.
The grains of long-grain rice tend to remain intact after cooking. Medium-grain rice is used for sweet dishes, for risotto in Italy, many rice dishes, such as arròs negre, in Spain; some varieties of long-grain rice that are high in amylopectin, known as Thai Sticky rice, are steamed. A stickier medium-grain rice is used for sushi. Medium-grain rice is used extensively in Japan, including to accompany savoury dishes, where it is served plain in a separate dish. Short-grain rice is used for rice pudding. Instant rice differs from parboiled rice in that it is cooked and dried, though there is a significant degradation in taste and texture. Rice flour and starch are used in batters and breadings to increase crispiness. Rice is rinsed before cooking to remove excess starch. Rice produced in the US is fortified with vitamins and minerals, rinsing will result in a loss of nutrients. Rice may be rinsed until the rinse water is clear to improve the texture and taste. Rice may be soaked to decrease cooking time, conserve fuel, minimize exposure to high temperature, reduce stickiness.
For some varieties, soaking improves the texture of the cooked rice by increasing expansion of the grains. Rice may be soaked for 30 minutes up to several hours. Brown rice may be soaked in warm water for 20 hours to stimulate germination; this process, called germinated brown rice, activates enzymes and enhances amino acids including gamma-aminobutyric acid to improve the nutritional value of brown rice. This method is a result of research carried out for the United Nations International Year of Rice. Rice is cooked by boiling or steaming, absorbs water during cooking. With the absorption method, rice may be cooked in a volume of water equal to the volume of dry rice- plus any evaporation losses. With the rapid-boil method, rice may be cooked in a large quantity of water, drained before serving. Rapid-boil preparation is not desirable with enriched rice, as much of the enrichment additives are l
A mangrove is a shrub or small tree that grows in coastal saline or brackish water. The term is used for tropical coastal vegetation consisting of such species. Mangroves occur worldwide in the tropics and subtropics between latitudes 25° N and 25° S; the total mangrove forest area of the world in 2000 was 137,800 square kilometres, spanning 118 countries and territories. Mangroves are salt-tolerant trees called halophytes, are adapted to life in harsh coastal conditions, they contain a complex salt filtration system and complex root system to cope with salt water immersion and wave action. They are adapted to the low oxygen conditions of waterlogged mud; the word is used in at least three senses: most broadly to refer to the habitat and entire plant assemblage or mangal, for which the terms mangrove forest biome, mangrove swamp are used, to refer to all trees and large shrubs in the mangrove swamp, narrowly to refer to the mangrove family of plants, the Rhizophoraceae, or more just to mangrove trees of the genus Rhizophora.
The mangrove biome, or mangal, is a distinct saline woodland or shrubland habitat characterized by depositional coastal environments, where fine sediments collect in areas protected from high-energy wave action. The saline conditions tolerated by various mangrove species range from brackish water, through pure seawater, to water concentrated by evaporation to over twice the salinity of ocean seawater; the term "mangrove" comes to English from Spanish, is to originate from Guarani. It was earlier "mangrow", but this word was corrupted via folk etymology influence of the word "grove". Mangrove swamps are found in subtropical tidal areas. Areas where mangals occur include marine shorelines; the intertidal existence to which these trees are adapted represents the major limitation to the number of species able to thrive in their habitat. High tide brings in salt water, when the tide recedes, solar evaporation of the seawater in the soil leads to further increases in salinity; the return of tide can flush out these soils, bringing them back to salinity levels comparable to that of seawater.
At low tide, organisms are exposed to increases in temperature and desiccation, are cooled and flooded by the tide. Thus, for a plant to survive in this environment, it must tolerate broad ranges of salinity and moisture, as well as a number of other key environmental factors—thus only a select few species make up the mangrove tree community. About 110 species are considered "mangroves", in the sense of being a tree that grows in such a saline swamp, though only a few are from the mangrove plant genus, Rhizophora. However, a given mangrove swamp features only a small number of tree species, it is not uncommon for a mangrove forest in the Caribbean to feature only three or four tree species. For comparison, the tropical rainforest biome contains thousands of tree species, but this is not to say mangrove forests lack diversity. Though the trees themselves are few in species, the ecosystem that these trees create provides a home for a great variety of other species. Mangrove plants require a number of physiological adaptations to overcome the problems of anoxia, high salinity and frequent tidal inundation.
Each species has its own solutions to these problems. Small environmental variations within a mangal may lead to differing methods for coping with the environment. Therefore, the mix of species is determined by the tolerances of individual species to physical conditions, such as tidal inundation and salinity, but may be influenced by other factors, such as predation of plant seedlings by crabs. Once established, mangrove roots provide an oyster habitat and slow water flow, thereby enhancing sediment deposition in areas where it is occurring; the fine, anoxic sediments under mangroves act as sinks for a variety of heavy metals which colloidal particles in the sediments have scavenged from the water. Mangrove removal disturbs these underlying sediments creating problems of trace metal contamination of seawater and biota. Mangrove swamps protect coastal areas from erosion, storm surge, tsunamis; the mangroves' massive root systems are efficient at dissipating wave energy. They slow down tidal water enough so its sediment is deposited as the tide comes in, leaving all except fine particles when the tide ebbs.
In this way, mangroves build their own environments. Because of the uniqueness of mangrove ecosystems and the protection against erosion they provide, they are the object of conservation programs, including national biodiversity action plans. Mangrove swamps' effectiveness in terms of erosion control can sometimes be overstated. Wave energy is low in areas where mangroves grow, so their effect on erosion is measured over long periods, their capacity to limit high-energy wave erosion is in relation to events such as storm surges and tsunamis. The unique ecosystem found in the intricate mesh of mangrove roots offers a quiet marine region for young organisms. In areas where roots are permanently submerged, the organisms they host include algae, oysters and bryozoans, which all require a hard surface for anchoring while they filter feed. Shrimps and mud lobsters use the muddy bottoms as their home. Mangrove crabs munch on the mangrove leaves, adding nutrients to the mangal muds for other bottom feeders.
In at least some cases, export of carbon fixed in mangroves is imp
The orange-winged amazon known locally as orange-winged parrot and loro guaro, is a large amazon parrot. It is a resident breeding bird in tropical South America, from Colombia and Tobago south to Peru and central Brazil, its habitat is semi-open country. Although common, it is persecuted by capture for the pet trade, it is hunted as a food source. Introduced breeding populations have been reported in Puerto Rico. There are two subspecies: A. a. amazonica, found on the mainland of South America. A. a. tobagensis, found only on Trinidad and Tobago, is a subspecies, larger than the nominate form, has more orange in the wing. The orange-winged amazon is a green parrot about 33 cm long and weighing about 340 g, it has yellow feathers on its head which varies in extent between individuals. The upper mandible is horn colored and dark-gray, it has orange feathers in the wings and tail. The male and female are identical in external appearance; the orange-winged amazons makes loud, high-pitched screams. It eats fruit and seeds, including the fruit of sometimes cocoa.
It roosts communally in palm and other trees, large numbers can be seen at the roost sites at dawn and dusk. It is becoming common as a feral bird in the Miami, Florida area, there are colonies in London, England; the orange-winged amazon nests in tree cavities. The eggs are white and there are three or four in a clutch; the female incubates the eggs for about 26 days and the chicks leave the nest about 60 days after hatching. Birds of Venezuela by Hilty, ISBN 0-7136-6418-5. Ffrench, Richard. A Guide to the Birds of Trinidad and Tobago. Comstock Publishing. ISBN 0-8014-9792-2. "National Geographic" Field Guide to the Birds of North America ISBN 0-7922-6877-6. Handbook of the Birds of the World Vol 4, Josep del Hoyo editor, ISBN 84-87334-22-9. "National Audubon Society" The Sibley Guide to Birds, by David Allen Sibley, ISBN 0-679-45122-6. "Amazon Parrots" - Faze magazine
The Ortoire River is a river in Trinidad and Tobago. It forms Mayaro County in east Trinidad, it is green in color and it once had an iron bridge with wooden planks but it has been replaced by an all paved concrete bridge. The river is famous for giving off light which appears blue in color every 10 years, this is due to the bioluminescence of living organisms residing in the water
The red-bellied macaw known as Guacamaya Manilata, is a medium-sized green South American parrot, a member of a group of large Neotropical parrots known as macaws. It is the largest of what are called "mini-macaws"; the belly has a large maroon patch. It is endemic to tropical Amazonian South America, from Colombia and Trinidad south to Amazonian Peru and Bolivia, central Brazil as far as the northwestern cerrado, its habitat is sandy savannahs with palm groves. They are critically dependent on the Moriche palm for roosting and nesting. Although the bird is locally common, in places it has been adversely affected by clearing of the palms for use as posts, or to allow cattle ranching. Not to be confused with the African red-bellied parrot, a named smaller parrot; the red-bellied macaw is a species of the monotypic genus Orthopsittaca, one of six genera of Central and South American macaws. Gender agreement of species name follows Gosselin, it was classified as Ara manilata. The protonym was Psittacus manilatus.
The genus name Orthopsittaca is from Gr. orthos straight. Hence, "a parrot with wide hands and straight nose "; the red-bellied macaw is medium-sized, about 300 g in weight and about 46 cm in length including its long pointed tail. The plumage is green; the forehead is bluish. The chin and upper chest are greyish with some green scalloping, the lower abdomen has a large maroon patch; the tail is tapered. The underwings and undertail are dull olive yellow. Adults have dark-grey beaks; the legs and feet are dark grey. In common with other parrots, they have two toes pointing forward and two backward. Males and females have identical plumage, but males are larger and have larger heads. Juveniles are duller in colour than adults and have a grey beak with a conspicuous white mid-line stripe running along the length of the culmen; the Spix's macaw is the only other macaw. Red-bellied macaws make reedy, high-pitched screams, they roost communally in the moriche palms, large numbers can be seen at the roost sites at dawn and dusk.
They choose large stands of these palms that have an overabundance of woodpecker holes as roosting sites. They sleep communally in these groups of hollows. Depending on the size of the hollow, between five and 10 birds sleep together; as dusk approaches, they all pile into these dormitories and sleep shoulder to shoulder. Their diet consists exclusively of the fruit and seeds of moriche palm, which are 100% carbohydrate, 0% fat and high in Beta-carotene. Red-bellied macaws nest in cavities of dead moriche palm trees. There are two to four white eggs in a clutch; the female incubates the eggs for about 27 days, the chicks fledge from the nest about 77 days after hatching. Juveniles reach sexual maturity in 2–3 years; the red-bellied macaw has an large range throughout the Amazon Basin of the North Region, except in the northwest quadrant centered on a large region of the Rio Negro flowing from Colombia-Venezuela. It ranges through the Guianas including the Guiana Highlands into eastern Venezuela, the lower Orinoco River Basin and across to the island of Trinidad.
Its southern limit in Brazil is the south-central and northwestern cerrado bordering the Amazon Basin. Red-bellied macaws are listed as "least concern" by the IUCN. Population numbers have not been estimated, it is difficult keep these birds alive in captivity, because of their high strung personality, low fat and high carbohydrate diet. Export/Import for the pet trade results in 100% mortality. Captive-bred chicks have a low survival rate; the only country to export these birds in recent years is Guyana. Because of lack of commercial availability of moriche palm nuts, shelled unsalted peanuts have been used as a staple in the diet of captive birds, they must not be fed commercial bird seed fatty seed like Sunflower. List of macaws ffrench, Richard. A Guide to the Birds of Trinidad and Tobago. Comstock Publishing. ISBN 0-8014-9792-2. Hilty, Steven L. Birds of Venezuela. London: Christopher Helm. ISBN 0-7136-6418-5. Forshaw, Joseph M.. Parrots of the World. Illustrated by Frank Knight. Princeton University Press.
ISBN 0-691-09251-6. Captive Reproduction of the Peculiar Red-bellied Macaw Red-bellied Macaw videos on the Internet Bird Collection Red-bellied Macaw photo gallery VIREO- Photo-High Res Video 1 depicting a pet Red-bellied Macaw Video 2 depicting a pet Red-bellied Macaw