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Salinity is the saltiness or dissolved salt content of a body of water. Salinity in Australian English may refer to salt in soil (see salinity in Australia).
Definitions
The salt content of most natural lakes, rivers, and streams is so small that these waters are termed fresh or even sweet water. The actual amount of salt in fresh water is, by definition, less than 0.05%. Otherwise, the water is regarded as brackish, or defined as saline if it contains 3 to 5% salt by volume. At well over 5% it is considered brine. The ocean is naturally saline at approximately 3.5% salt (see sea water). Some inland salt lakes or seas are even saltier. The Dead Sea, for example, has a surface water salt content of around 15%.
The technical term for saltiness in the ocean is halinity, from the fact that halides—chloride specifically—are the most abundant anion in the mix of dissolved elements. In oceanography, it has been traditional to express halinity not as percent, but as parts per thousand (ppt or ‰), which is approximately grams of salt per liter of solution. Prior to 1978, salinity or halinity was expressed as ‰ usually based on the electrical conductivity ratio of the sample to "Copenhagen water", an artificial sea water manufactured to serve as a world "standard". In 1978, oceanographers redefined salinity in Practical Salinity Units (psu): the conductivity ratio of a sea water sample to a standard KCl solution. Ratios have no units, so it is not the case that 35 psu exactly equals 35 grams of salt per litre of solution.
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USDA Agricultural Research Service
"Fingerprinting" Helps Make Great Grapes
Tue, 26 Aug 2008 09:49:00 -0500
Genetic fingerprints, now being developed for the 2,800 wild, rare and domesticated grapes in ARS's northern California genebank, will help grape breeders pinpoint unusual characteristics. Click the image for more information about it. Autumn King seedless grapes: Big and luscious! Thomcord grape: Flavorful, attractive—and seedless! Sweet Scarlet grape: New variety readied for growers “Fingerprinting” Helps Make Great Grapes By Marcia Wood August 26, 2008 At about this time next year, nearly all of the 2,800 wild, rare and domesticated grapes in a unique northern California genebank will have had their "genetic profile" or “fingerprint” taken. These fingerprints may help grape breeders pinpoint plants in the collection that have unusual traits--ones that might appeal to shoppers in tomorrow's supermarkets. Other grapes might be ideal for scientists who are doing basic research. That’s according to Agricultural Research Service (ARS) plant geneticist Mallikarjuna Aradhya. He's heading the grape fingerprinting venture. The grape collection that Aradhya is fingerprinting encompasses vineyards and screened enclosures, called “screenhouses." It is part of what’s officially known as the ARS National Clonal Germplasm Repository for Tree Fruit and Nut Crops and Grapes, in Davis, Calif. To glean a distinctive genetic fingerprint of each member of the collection, Aradhya uses pieces of genetic material--or DNA--known as microsatellite markers. Eight markers are all that are needed for a genetic fingerprint of more familiar grapes, like close relatives of those already used for making wine or raisins or for eating out-of-hand. But the lesser-known ones--wild grapes and some prized types from China, for instance--require twice as many markers for reliable identification. That’s due, in part, to the fact that the taxonomy, or relatedness of one kind of grape to another, is quite jumbled, Aradhya noted. He has already fingerprinted 1,100 better-known grapes and 300 wild specimens. ARS is a scientific research agency of the U.S. Department of Agriculture.
Hydrogen-Producing Bacteria Studied
Mon, 25 Aug 2008 08:15:00 -0500
Researchers are now identifying nitrogen-fixing bacteria that release all of the hydrogen the microbes produce, which could lead to a new hydrogen source for fuel cells. Photo courtesy of Department of Energy. Switchgrass: Bridging bioenergy and conservation Biofuel crops double as greenhouse-gas reducers Making gas from crop residue Hydrogen-Producing Bacteria Provide Clean Energy By Rosalie Marion Bliss August 25, 2008 A new "green" technology developed cooperatively by scientists with the Agricultural Research Service (ARS) and North Carolina State University (NC State) could lead to production of hydrogen from nitrogen-fixing bacteria. Renewable sources of energy—such as hydrogen—that don't produce pollutants or greenhouse gases are needed to solve global energy shortages. Fossil fuels such as coal, oil and natural gas are nonrenewable energy sources implicated in global warming. The invention holds promise as a source of hydrogen for use in fuel cell technology. Fuel cell devices combine hydrogen and oxygen to produce electricity and water, and are considered efficient, quiet and pollution-free. Fuel cells are now being tested in a range of products, including automobiles that release no emissions other than water vapor. ARS inventors Paul Bishop and Telisa Loveless and NC State inventors Jonathan Olson and José Bruno-Bárcena developed the patent-pending technology. Nitrogen-fixing bacteria play a key role in agriculture. They live in soil and on certain plant roots, and convert nitrogen from the air into a chemical form that plants can use to grow. The researchers developed a way to identify strains of these bacteria that produce hydrogen gas. Bishop first demonstrated novel aspects of bacterial nitrogen-fixing more than two decades ago. Building on that work, the team developed a method that uses a selecting agent to identify these special hydrogen-producing strains. The selecting agent allows researchers to identify these bacterial strains without the need for genomic sequencing or genetic modification. Using the selecting agent, the inventors identified a gene that inactivates the bacteria's hydrogen uptake system so that all of the hydrogen produced is released. Because the bacterial cells cannot recycle the hydrogen, the hydrogen they produce can be captured and used as a fuel whose byproduct is water and heat. Licensing information can be obtained by contacting the ARS Office of Technology Transfer or the Office of Technology Transfer at NC State. ARS is a scientific research agency of the U.S. Department of Agriculture.
Chickpea Fungus Investigated
Fri, 22 Aug 2008 08:26:00 -0500
Chickpeas. Photo courtesy of USDA/GIPSA. Likeable legume snacks from ARS research Meeting showcases anti-Sclerotinia research New chickpea variety available for legume lovers Scientists Tie Chickpea Disease to Fungal Culprit By Jan Suszkiw August 22, 2008 The fungus Sclerotinia trifoliorum plagues legume crops worldwide. But chickpeas seem to have escaped its wrath, with the exception of Australia's crop. Now, that's no longer the case, report Agricultural Research Service (ARS) and collaborative university scientists. During the 2005-06 chickpea growing season in central California, the team observed stem and crown rots reminiscent of Sclerotinia infection. But subtle irregularities in the symptoms led the researchers to believe their prime suspect—S. sclerotiorum, which infects more 400 plant species—had an accomplice, namely S. trifoliorum. ARS research plant pathologist Weidong Chen led the team, which included Fred Muehlbauer (now retired) with the ARS Grain Legume Genetics Physiology Research Unit in Pullman, Wash., and University of California-Davis and Washington State University researchers. They examined 10 Sclerotinia isolates from their collection from chickpea stems and subjected each to three identification criteria: growth rate, ascospore morphology and DNA markers indicative of S. trifoliorum. The team's analysis showed that S. trifoliorum isolates were slower-growing, displayed "ascospore dimorphism," which is the formation of two versions of the same spore type, and harbored a set of group I intron markers while S. sclerotiorum did not. Chen suspects S. trifoliorum's occurrence on central California chickpeas stems from prior plantings of alfalfa—another legume host—and not an accidental introduction from Australia, the only continent where the fungus has previously been reported on chickpea. Identification of this new chickpea pathogen should aid in improving disease-management practices and developing resistant chickpea cultivars for farmers. The research is part of the ARS National Sclerotinia Initiative. More information on this initiative is available at: http://www.whitemoldresearch.com The research study was published recently in the journal Plant Disease, and is available online at: http://apsjournals.apsnet.org/doi/interp/10.1094/PDIS-92-6-0917 ARS is a scientific research agency of the U.S. Department of Agriculture.
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"Fingerprinting" Helps Make Great Grapes
Tue, 26 Aug 2008 09:49:00 -0500
Genetic fingerprints, now being developed for the 2,800 wild, rare and domesticated grapes in ARS's northern California genebank, will help grape breeders pinpoint unusual characteristics. Click the image for more information about it. Autumn King seedless grapes: Big and luscious! Thomcord grape: Flavorful, attractive—and seedless! Sweet Scarlet grape: New variety readied for growers “Fingerprinting” Helps Make Great Grapes By Marcia Wood August 26, 2008 At about this time next year, nearly all of the 2,800 wild, rare and domesticated grapes in a unique northern California genebank will have had their "genetic profile" or “fingerprint” taken. These fingerprints may help grape breeders pinpoint plants in the collection that have unusual traits--ones that might appeal to shoppers in tomorrow's supermarkets. Other grapes might be ideal for scientists who are doing basic research. That’s according to Agricultural Research Service (ARS) plant geneticist Mallikarjuna Aradhya. He's heading the grape fingerprinting venture. The grape collection that Aradhya is fingerprinting encompasses vineyards and screened enclosures, called “screenhouses." It is part of what’s officially known as the ARS National Clonal Germplasm Repository for Tree Fruit and Nut Crops and Grapes, in Davis, Calif. To glean a distinctive genetic fingerprint of each member of the collection, Aradhya uses pieces of genetic material--or DNA--known as microsatellite markers. Eight markers are all that are needed for a genetic fingerprint of more familiar grapes, like close relatives of those already used for making wine or raisins or for eating out-of-hand. But the lesser-known ones--wild grapes and some prized types from China, for instance--require twice as many markers for reliable identification. That’s due, in part, to the fact that the taxonomy, or relatedness of one kind of grape to another, is quite jumbled, Aradhya noted. He has already fingerprinted 1,100 better-known grapes and 300 wild specimens. ARS is a scientific research agency of the U.S. Department of Agriculture.
Hydrogen-Producing Bacteria Studied
Mon, 25 Aug 2008 08:15:00 -0500
Researchers are now identifying nitrogen-fixing bacteria that release all of the hydrogen the microbes produce, which could lead to a new hydrogen source for fuel cells. Photo courtesy of Department of Energy. Switchgrass: Bridging bioenergy and conservation Biofuel crops double as greenhouse-gas reducers Making gas from crop residue Hydrogen-Producing Bacteria Provide Clean Energy By Rosalie Marion Bliss August 25, 2008 A new "green" technology developed cooperatively by scientists with the Agricultural Research Service (ARS) and North Carolina State University (NC State) could lead to production of hydrogen from nitrogen-fixing bacteria. Renewable sources of energy—such as hydrogen—that don't produce pollutants or greenhouse gases are needed to solve global energy shortages. Fossil fuels such as coal, oil and natural gas are nonrenewable energy sources implicated in global warming. The invention holds promise as a source of hydrogen for use in fuel cell technology. Fuel cell devices combine hydrogen and oxygen to produce electricity and water, and are considered efficient, quiet and pollution-free. Fuel cells are now being tested in a range of products, including automobiles that release no emissions other than water vapor. ARS inventors Paul Bishop and Telisa Loveless and NC State inventors Jonathan Olson and José Bruno-Bárcena developed the patent-pending technology. Nitrogen-fixing bacteria play a key role in agriculture. They live in soil and on certain plant roots, and convert nitrogen from the air into a chemical form that plants can use to grow. The researchers developed a way to identify strains of these bacteria that produce hydrogen gas. Bishop first demonstrated novel aspects of bacterial nitrogen-fixing more than two decades ago. Building on that work, the team developed a method that uses a selecting agent to identify these special hydrogen-producing strains. The selecting agent allows researchers to identify these bacterial strains without the need for genomic sequencing or genetic modification. Using the selecting agent, the inventors identified a gene that inactivates the bacteria's hydrogen uptake system so that all of the hydrogen produced is released. Because the bacterial cells cannot recycle the hydrogen, the hydrogen they produce can be captured and used as a fuel whose byproduct is water and heat. Licensing information can be obtained by contacting the ARS Office of Technology Transfer or the Office of Technology Transfer at NC State. ARS is a scientific research agency of the U.S. Department of Agriculture.
Chickpea Fungus Investigated
Fri, 22 Aug 2008 08:26:00 -0500
Chickpeas. Photo courtesy of USDA/GIPSA. Likeable legume snacks from ARS research Meeting showcases anti-Sclerotinia research New chickpea variety available for legume lovers Scientists Tie Chickpea Disease to Fungal Culprit By Jan Suszkiw August 22, 2008 The fungus Sclerotinia trifoliorum plagues legume crops worldwide. But chickpeas seem to have escaped its wrath, with the exception of Australia's crop. Now, that's no longer the case, report Agricultural Research Service (ARS) and collaborative university scientists. During the 2005-06 chickpea growing season in central California, the team observed stem and crown rots reminiscent of Sclerotinia infection. But subtle irregularities in the symptoms led the researchers to believe their prime suspect—S. sclerotiorum, which infects more 400 plant species—had an accomplice, namely S. trifoliorum. ARS research plant pathologist Weidong Chen led the team, which included Fred Muehlbauer (now retired) with the ARS Grain Legume Genetics Physiology Research Unit in Pullman, Wash., and University of California-Davis and Washington State University researchers. They examined 10 Sclerotinia isolates from their collection from chickpea stems and subjected each to three identification criteria: growth rate, ascospore morphology and DNA markers indicative of S. trifoliorum. The team's analysis showed that S. trifoliorum isolates were slower-growing, displayed "ascospore dimorphism," which is the formation of two versions of the same spore type, and harbored a set of group I intron markers while S. sclerotiorum did not. Chen suspects S. trifoliorum's occurrence on central California chickpeas stems from prior plantings of alfalfa—another legume host—and not an accidental introduction from Australia, the only continent where the fungus has previously been reported on chickpea. Identification of this new chickpea pathogen should aid in improving disease-management practices and developing resistant chickpea cultivars for farmers. The research is part of the ARS National Sclerotinia Initiative. More information on this initiative is available at: http://www.whitemoldresearch.com The research study was published recently in the journal Plant Disease, and is available online at: http://apsjournals.apsnet.org/doi/interp/10.1094/PDIS-92-6-0917 ARS is a scientific research agency of the U.S. Department of Agriculture.
USDA - Agriculture
Avian Influenza, Bird Flu
The official U.S. government web site for information on pandemic flu and avian influenza
Pest Management
Pest management policy, pesticide screening tool, evaluate pesticide risk, conservation buffers, training modules.
Weather and Climate
U.S. agricultural weather highlights, weekly weather and crop bulletin, major world crop areas and climatic profiles.
Dry land salinity in Australia - Detailed description of the difference between dry land salinity and irrigated land salinity. Shows areas of Australia most affected and measures to reduce salinity. Glossary of terms and links to further reading.
National Dryland Salinity Program - Is a collaborative research and development effort that is investigating the causes of, and solutions to, the problem of dryland salinity in Australia.
US Salinity Laboratory - Basic research on the chemistry, physics, biology, and assessment of salt-affected soil-plant-water systems.
Meta Description: [ The GEORGE E BROWN JR Salinity Laboratory, a National Laboratory for basic research
on the chemistry, ph
ysics, biology, and assessment of salt-affected soil-plant-water systems.
(Riverside CA USA) ]
Web Links: Salinity - With the headings : general resources, Australian and International resourcesand Organisations and Associations.
| This robot utilizes the Vernier Salinity Sensor connnected to the NXT. The purpose of the device is to increase the salt ... | |
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