Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root brak. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment.
Entropy is a scientific concept, as well as a measurable physical property, that is most commonly associated with a state of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the microscopic description of nature in statistical physics, and to the principles of information theory. It has found far-ranging applications in chemistry and physics, in biological systems and their relation to life, in cosmology, economics, sociology, weather science, climate change, and information systems including the transmission of information in telecommunication.
The smallmouth bass is a species of freshwater fish in the sunfish family (Centrarchidae) of the order Perciformes. It is the type species of its genus Micropterus, and is a popular game fish sought by anglers throughout the temperate zones of North America, and has been spread by stocking—as well as illegal introductions—to many cool-water tributaries and lakes in Canada and more so introduced in the United States. The maximum recorded size is approximately 27 inches (69 cm) and 12 pounds (5.4 kg).
The underwater environment is the region below the surface of, and immersed in, liquid water in a natural or artificial feature, such as an ocean, sea, lake, pond, reservoir, river, canal, or aquifer. Some characteristics of the underwater environment are universal, but many depend on the local situation.
A Carnot cycle is an ideal thermodynamic cycle proposed by French physicist Sadi Carnot in 1824 and expanded upon by others in the 1830s and 1840s. By Carnot's theorem, it provides an upper limit on the efficiency of any classical thermodynamic engine during the conversion of heat into work, or conversely, the efficiency of a refrigeration system in creating a temperature difference through the application of work to the system.
The Klamath Basin is the region in the U.S. states of Oregon and California drained by the Klamath River. It contains most of Klamath County and parts of Lake and Jackson counties in Oregon, and parts of Del Norte, Humboldt, Modoc, Siskiyou, and Trinity counties in California. The 15,751-square-mile (40,790 km2) drainage basin is 35% in Oregon and 65% in California. In Oregon, the watershed typically lies east of the Cascade Range, while California contains most of the river's segment that passes through the mountains. In the Oregon-far northern California segment of the river, the watershed is semi-desert at lower elevations and dry alpine in the upper elevations. In the western part of the basin, in California, however, the climate is more of temperate rainforest, and the Trinity River watershed consists of a more typical alpine climate.
The northern red-bellied turtle or American red-bellied turtle is a species of turtle in the Pseudemys (cooter) genus of the family Emydidae.
The freshwater cobbler, Tandanus bostocki, is a species of catfish of the family Plotosidae. The freshwater cobbler originates from coastal drainages of southwestern Australia, from the Frankland River to the Moore River. The species may reach about 50 centimetres (20 in) total length.
Limnohabitans is a genus of bacteria established by Hahn et al. (2010). The genus contains four species which all represent planktonic bacteria dwelling in the water column of freshwater lakes, reservoirs, and streams.
Limnohabitans planktonicus is a Gram-negative, oxidase- and catalase-positive, aerobic, unpigmented bacterium from the genus Limnohabitans, which was isolated from the mesoeutrophic freshwater reservoir in Římov in the Czech Republic.
Limnohabitans parvus is a Gram-negative, aerobic, oxidase- and catalase-positive, unpigmented, short-rod-shaped, nonmotile bacterium from the genus Limnohabitans, which was isolated with Limnohabitans planktonicus from the mesoeutrophic freshwater reservoir in Římov in the Czech Republic.
Chlorobium chlorochromatii, originally known as Chlorobium aggregatum, is a symbiotic green sulfur bacteria that performs anoxygenic photosynthesis and functions as an obligate photoautotroph using reduced sulfur species as electron donors. Chlorobium chlorochromatii can be found in stratified freshwater lakes.
Flavobacterium dankookense is a Gram-negative, rod-shaped and strictly aerobic bacterium from the genus of Flavobacterium which has been isolated from a freshwater lake from Cheonan in Korea.
Flavisolibacter rigui is a Gram-negative, aerobic, rod-shaped and non-motile bacterium from the genus of Flavisolibacter which has been isolated from freshwater from the Juam Reservoir in Korea.
Lacibacter daechungensis is a Gram-negative, aerobic, rod-shaped, non-spore-forming and motile bacterium from the genus of Lacibacter which has been isolated from deep freshwater from the Daechung reservoir in Korea.
Sediminibacterium aquarii is a Gram-negative, rod-shaped and strictly aerobic bacterium from the genus of Sediminibacterium which has been isolated from sediments from a fish bowl.
Sediminibacterium ginsengisoli is a Gram-negative, non-spore-forming, facultatively anaerobic and motile bacterium from the genus of Sediminibacterium which has been isolated from soil from a ginseng field from Pocheon in Korea.
Sediminibacterium salmoneum is a Gram-negative and motile bacterium from the genus of Sediminibacterium which has been isolated from sediments from the Guanting Reservoir from Beijing in China.
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include non-salty mineral-rich waters such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Fresh water is the water resource that is of the most and immediate use to humans.
