Fertilizers: Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.Soil: The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.Agriculture: The science, art or practice of cultivating soil, producing crops, and raising livestock.Manure: Accumulations of solid or liquid animal excreta usually from stables and barnyards with or without litter material. Its chief application is as a fertilizer. (From Webster's 3d ed)Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Crops, Agricultural: Cultivated plants or agricultural produce such as grain, vegetables, or fruit. (From American Heritage Dictionary, 1982)Chemistry, Agricultural: The science of the chemical composition and reactions of chemicals involved in the production, protection and use of crops and livestock. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Nitrates: Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.Humic Substances: Organic matter in a state of advanced decay, after passing through the stages of COMPOST and PEAT and before becoming lignite (COAL). It is composed of a heterogenous mixture of compounds including phenolic radicals and acids that polymerize and are not easily separated nor analyzed. (E.A. Ghabbour & G. Davies, eds. Humic Substances, 2001).Nitrogen Compounds: Inorganic compounds that contain nitrogen as an integral part of the molecule.Carbon Footprint: A measure of the total greenhouse gas emissions produced by an individual, organization, event, or product. It is measured in units of equivalent kilograms of CARBON DIOXIDE generated in a given time frame.Environmental Pollution: Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.Water Pollution, Chemical: Adverse effect upon bodies of water (LAKES; RIVERS; seas; groundwater etc.) caused by CHEMICAL WATER POLLUTANTS.Soil Microbiology: The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.Phosphorus: A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.Hydrology: Science dealing with the properties, distribution, and circulation of water on and below the earth's surface, and atmosphere.Eichhornia: A plant genus of the family PONTEDERIACEAE that is used as a biological filter for treating wastewater.Soil Pollutants: Substances which pollute the soil. Use for soil pollutants in general or for which there is no specific heading.Greenhouse Effect: The effect of GLOBAL WARMING and the resulting increase in world temperatures. The predicted health effects of such long-term climatic change include increased incidence of respiratory, water-borne, and vector-borne diseases.Groundwater: Liquid water present beneath the surface of the earth.Ananas: A plant genus of the family BROMELIACEAE known for the edible fruit that is the source of BROMELAINS.Water Quality: A rating of a body of water based on measurable physical, chemical, and biological characteristics.UzbekistanConservation of Natural Resources: The protection, preservation, restoration, and rational use of all resources in the total environment.Biomass: Total mass of all the organisms of a given type and/or in a given area. (From Concise Dictionary of Biology, 1990) It includes the yield of vegetative mass produced from any given crop.Waste Management: Disposal, processing, controlling, recycling, and reusing the solid, liquid, and gaseous wastes of plants, animals, humans, and other organisms. It includes control within a closed ecological system to maintain a habitable environment.Zea mays: A plant species of the family POACEAE. It is a tall grass grown for its EDIBLE GRAIN, corn, used as food and animal FODDER.Methylomonas: A genus of gram-negative, aerobic, straight, curved, or branched rods which are motile by a single polar flagellum. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Amaranthus: A plant genus, in the family AMARANTHACEAE, best known as a source of high-protein grain crops and of Red Dye No. 2 (AMARANTH DYE). Tumbleweed sometimes refers to Amaranthus but more often refers to SALSOLA.Fossil Fuels: Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.Waste Products: Debris resulting from a process that is of no further use to the system producing it. The concept includes materials discharged from or stored in a system in inert form as a by-product of vital activities. (From Webster's New Collegiate Dictionary, 1981)Agrochemicals: Chemicals used in agriculture. These include pesticides, fumigants, fertilizers, plant hormones, steroids, antibiotics, mycotoxins, etc.Environmental Monitoring: The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.Chemical Industry: The aggregate enterprise of manufacturing and technically producing chemicals. (From Random House Unabridged Dictionary, 2d ed)Minerals: Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Organic Agriculture: Systems of agriculture which adhere to nationally regulated standards that restrict the use of pesticides, non-organic fertilizers, genetic engineering, growth hormones, irradiation, antibiotics, and non-organic ANIMAL FEED.Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Nitrous Oxide: Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.Primulaceae: A plant family of the order Primulales, subclass Dilleniidae, class Magnoliopsida. The flowers have both stamens and pistil, and the fruits are capsules.Phytochemicals: A broad range of biologically active compounds which occur naturally in plants having important medicinal and nutritional properties.NebraskaConservation of Energy Resources: Planned management, use, and preservation of energy resources.Rhizosphere: The immediate physical zone surrounding plant roots that include the plant roots. It is an area of intense and complex biological activity involving plants, microorganisms, other soil organisms, and the soil.Paspalum: A plant genus of the family POACEAE that is used for forage.Nitrogen Fixation: The process in certain BACTERIA; FUNGI; and CYANOBACTERIA converting free atmospheric NITROGEN to biologically usable forms of nitrogen, such as AMMONIA; NITRATES; and amino compounds.Fuel Oils: Complex petroleum hydrocarbons consisting mainly of residues from crude oil distillation. These liquid products include heating oils, stove oils, and furnace oils and are burned to generate energy.Rain: Water particles that fall from the ATMOSPHERE.Ammonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.Triticum: A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.Weed Control: The prevention of growth and or spread of unwanted plants.Water Pollutants: Substances or organisms which pollute the water or bodies of water. Use for water pollutants in general or those for which there is no specific heading.Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)Nitrogen Cycle: The circulation of nitrogen in nature, consisting of a cycle of biochemical reactions in which atmospheric nitrogen is compounded, dissolved in rain, and deposited in the soil, where it is assimilated and metabolized by bacteria and plants, eventually returning to the atmosphere by bacterial decomposition of organic matter.Ecological and Environmental Processes: Ecosystem and environmental activities, functions, or events.Water Movements: The flow of water in enviromental bodies of water such as rivers, oceans, water supplies, aquariums, etc. It includes currents, tides, and waves.Vicia: A plant genus of the family FABACEAE that is widely used as ground cover and forage and known for the edible beans, VICIA FABA.Water Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.Solid Waste: Garbage, refuse, or sludge, or other discarded materials from a wastewater treatment plant, water supply treatment plant, and air pollution control facility that include solid, semi-solid, or contained material. It does not include materials dissolved in domestic sewage, irrigation return flows, or industrial discharges.Pesticides: Chemicals used to destroy pests of any sort. The concept includes fungicides (FUNGICIDES, INDUSTRIAL); INSECTICIDES; RODENTICIDES; etc.Atmosphere: The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)Food Supply: The production and movement of food items from point of origin to use or consumption.
Organic fertilizer: Organic fertilizers are fertilizers derived from animal matter, human excreta or vegetable matter. (e.Index of soil-related articles: This is an index of articles relating to soil.Chilalo Agricultural Development Union: Chilalo Agricultural Development Union (CADU) is the first comprehensive package project established in Arsi Zone, Oromia Region, Ethiopia to modernize traditional subsistence agriculture. The major components of the package programmes include fertilizers, ameliorated seeds, farm credits, marketing facilities, better tools and implements, and improved storage facilities.Manure management: Manure management refers to capture, storage, treatment, and utilization of animal manures in an environmentally sustainable manner. It can be retained in various holding facilities.Nitrogen deficiencyPlant breeders' rights: Plant breeders' rights (PBR), also known as plant variety rights (PVR), are rights granted to the breeder of a new variety of plant that give the breeder exclusive control over the propagating material (including seed, cuttings, divisions, tissue culture) and harvested material (cut flowers, fruit, foliage) of a new variety for a number of years.Masuzo Shikata: Masuzo Shikata (Tokyo, August 10, 1895 – May 8, 1964) was a Japanese chemist and one of the pioneers in electrochemistry. Together with his mentor and colleague, Czech chemist and inventor Jaroslav Heyrovský, he developed the first polarograph, a type of electrochemical analyzing machine, and co-authored the paper which introduced the machine and the name "polarograph".Peroxynitrous acidHumic acid: Humic acid is a principal component of humic substances, which are the major organic constituents of soil (humus), peat and coal. It is also a major organic constituent of many upland streams, dystrophic lakes, and ocean water.Nitrogen trichlorideGreenhouse gas emissions by the United KingdomPolarized light pollution: Polarization is a property of light waves that describes the orientation of their oscillations. Polarized light pollutionGábor Horváth, György Kriska, Péter Malik, Bruce Robertson.Gemmatimonadetes: The Gemmatimonadetes are a family of bacteria, given their own phylum (Gemmatimonadetes). This bacterium makes up about 2% of soil bacterial communities and has been identified as one of the top nine phyla found in soils; yet, there are currently only six cultured isolates.Phosphorus deficiency: Phosphorus deficiency is a plant disorder associated with insufficient supply of phosphorus. Phosphorus refers here to salts of phosphates (PO43−), monohydrogen phosphate (HPO42−), and dihydrogen phosphate (H2PO4−).Outline of hydrology: The following outline is provided as an overview of and topical guide to hydrology:Eichhornia crassipes: Eichhornia crassipes, commonly known as (common) water hyacinth, is an aquatic plant native to the Amazon basin, and is often considered a highly problematic invasive species outside its native range.PyromorphiteIPCC Second Assessment Report: The Second Assessment Report (SAR) of the Intergovernmental Panel on Climate Change (IPCC), published in 1996, is an assessment of the then available scientific and socio-economic information on climate change. It was superseded by the Third Assessment Report (TAR) in 2001.Groundwater model: Groundwater models are computer models of groundwater flow systems, and are used by hydrogeologists. Groundwater models are used to simulate and predict aquifer conditions.Pineapple black rot: Pineapple black rot, also known as butt rot, base rot, or white blister, is a disease caused by Ceratocystis paradoxa (Dade) Moreau (Anamorph: Thielaviopsis paradoxa (De Seyenes) Höhnel) is the most common and well-known post-harvest disease of the pineapple fruit which is responsible for serious losses in the fresh pineapple fruit world industry.Water quality law: Water quality laws govern the release of pollutants into water resources, including surface water, ground water, and stored drinking water. Some water quality laws, such as drinking water regulations, may be designed solely with reference to human health.Iran–Uzbekistan relations: Iran–Uzbekistan relations refers to the diplomatic relations between the two Middle-eastern countries, Uzbekistan and Iran, which have deep cultural and historical ties between them. Both countries are members of the Economic Cooperation Organization (ECO).Meramec Conservation AreaIndex of waste management articles: Articles related to waste management include:Southern corn leaf blight: Southern corn leaf blight (SCLB) is a fungal disease of maize caused by the plant pathogen Bipolaris maydis (also known as Cochliobolus heterostrophus in its teleomorph state).Methylomonas methanica: Methylomonas methanica is a Gram-negative bacterium that obtains its carbon and energy from methane, a metabolic process called methanotrophy.. It is found in lakes, ponds, freshwater sediment and marshy ground.Agnes Benidickson Tricolour Award: The Tricolour Award and induction into the Tricolour Society is the highest tribute that can be paid to a student of Queen's University in Kingston, Ontario for valuable and distinguished service to the University in non-academic and non-athletic activities. Such service may have been confined to a single field, or it may have taken the form of a significant contribution over a wide range of activities.Phlogiston theory: The phlogiston theory is an obsolete scientific theory that postulated that a fire-like element called phlogiston is contained within combustible bodies and released during combustion. The name comes from the Ancient Greek [phlogistón (burning up), from φλόξ] phlóx (flame).Carbonization: Carbonization (or carbonisation) is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in organic chemistry with reference to the generation of coal gas and coal tar from raw coal.Agrochemical F.C.: James Omondi|Advanced Chemical Industries (ACI): ৳ 238 Million http://www.aci-bd.List of minerals (complete): Mineralogy is an active science in which minerals are discovered or recognised on a regular basis. Use of old mineral names is also discontinued, for example when a name is no longer considered valid.Organic farming and biodiversity: The effect of organic farming has been a subject of interest for researchers. Theory suggests that organic farming practices, which exclude the use of synthetic pesticides and fertilizers, would be beneficial for biodiversity, and this has proven true.EcosystemNitrous oxide and oxygen: A mix of nitrous oxide 50% and oxygen 50% is a medical analgesic gas, commonly known as Entonox (a registered trademark of BOC) or Nitronox, or colloquially as "gas and air", and is frequently used in pre-hospital care, childbirth and emergency medicine situations by medical professionals such as doctors, nurses, midwives and paramedics.Dodecatheon: Dodecatheon is a genus of herbaceous flowering plants in the family Primulaceae. The species have basal clumps of leaves and nodding flowers that are produced at the top of tall stems rising from where the leaves join the crown.Phytochemical: Phytochemicals are chemical compounds that occur naturally in plants (phyto means "plant" in Greek). Some are responsible for color and other organoleptic properties, such as the deep purple of blueberries and the smell of garlic.University of Nebraska Medical Center College of Dentistry: The University of Nebraska Medical Center College of Dentistry is located on the East Campus of the University of Nebraska at Lincoln. The College offers degrees in Doctor of Dental Surgery (DDS) and Registered Dental Hygienist (RDH).Energy policy of Malaysia: The energy policy of Malaysia is determined by the Malaysian Government, which address issues of energy production, distribution, and consumption. The Department of Electricity and Gas Supply acts as the regulator while other players in the energy sector include energy supply and service companies, research and development institutions and consumers.Rhizosphere: The rhizosphere is the narrow region of soil that is directly influenced by root secretions and associated soil microorganisms. Soil which is not part of the rhizosphere is known as bulk soil.Paspalum notatum: Paspalum notatum, known commonly as bahiagrass, common bahia, and Pensacola bahia, is a tropical to subtropical perennial grass (family Poaceae). It is known for its prominent V-shaped inflorescence consisting of two spike-like racemes containing multiple tiny spikelets, each about long.Diazotroph: Diazotrophs are bacteria and archaea that fix atmospheric nitrogen gas into a more usable form such as ammonia.Glen Davis Shale Oil Works: The Glen Davis Shale Oil Works was a shale oil extraction plant in Glen Davis, New South Wales, Australia which operated from 1940 until 1952 and was the last oil-shale operation in Australia until the Stuart Oil Shale Project in the late 1990s.The Rain Rain Rain Came Down Down Down: "The Rain Rain Rain Came Down Down Down" is a narrative song from the Walt Disney musical film featurette, Winnie the Pooh and the Blustery Day. The song is also incorporated into the 1977 musical film The Many Adventures of Winnie the Pooh which is an amalgamation of three Winnie-the-Pooh featurettes including "Blustery Day".Ammonia transporterWheat middlings: Wheat middlings (also known as millfeed, wheat mill run, or wheat midds) is the middle of three grades into which flour and meal are classified: patents, middlings, and clears. Middlings are often used in animal feed.Weed control: Weed control is the botanical component of pest control, which attempts to stop weeds, especially noxious or injurious weeds, from competing with domesticated plants and livestock. Many strategies have been developed in order to contain these plants.Endodermis: The endodermis is the central, innermost layer of cortex in some land plants. It is made of compact living cells surrounded by an outer ring of endodermal cells that are impregnated with hydrophobic substances (Casparian Strip) to restrict apoplastic flow of water to the inside.Human impact on the nitrogen cycleClean Water State Revolving Fund: The Clean Water State Revolving Fund (CWSRF) is a self-perpetuating loan assistance authority for water quality improvement projects in the United States. The fund is administered by the Environmental Protection Agency and state agencies.Hydraulic action: Hydraulic action is erosion that occurs when the motion of water against a rock surface produces mechanical weathering. Most generally, it is the ability of moving water (flowing or waves) to dislodge and transport rock particles.Vicia cracca: Vicia cracca (tufted vetch, cow vetch, bird vetch, blue vetch, boreal vetch), is a species of vetch native to Europe and Asia. It occurs on other continents as an introduced species, including North America, where it is a common weed.The Doors of His Face, The Lamps of His Mouth, and Other Stories: The Doors of His Face, The Lamps of His Mouth is a collection of science fiction short stories by Roger Zelazny and the title of the first story in the collection. It was published in 1971 by Doubleday.Pesticides in the United States: Pesticides in the United States are used predominantly by the agricultural sector,Kellogg RL, Nehring R, Grube A, Goss DW, and Plotkin S (February 2000), Environmental indicators of pesticide leaching and runoff from farm fields. United States Department of Agriculture Natural Resources Conservation Service.Stratosphere: The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. It is stratified in temperature, with warmer layers higher up and cooler layers farther down.Food desert: A food desert is a geographic area where affordable and nutritious food is difficult to obtain, particularly for those without access to an automobile.USDA Defines Food Deserts | American Nutrition Association Some research links food deserts to diet-related health problems and health disparities in affected populations, but this phenomenon has been disputed.
(1/404) Global environmental impacts of agricultural expansion: the need for sustainable and efficient practices.
The recent intensification of agriculture, and the prospects of future intensification, will have major detrimental impacts on the nonagricultural terrestrial and aquatic ecosystems of the world. The doubling of agricultural food production during the past 35 years was associated with a 6.87-fold increase in nitrogen fertilization, a 3.48-fold increase in phosphorus fertilization, a 1.68-fold increase in the amount of irrigated cropland, and a 1.1-fold increase in land in cultivation. Based on a simple linear extension of past trends, the anticipated next doubling of global food production would be associated with approximately 3-fold increases in nitrogen and phosphorus fertilization rates, a doubling of the irrigated land area, and an 18% increase in cropland. These projected changes would have dramatic impacts on the diversity, composition, and functioning of the remaining natural ecosystems of the world, and on their ability to provide society with a variety of essential ecosystem services. The largest impacts would be on freshwater and marine ecosystems, which would be greatly eutrophied by high rates of nitrogen and phosphorus release from agricultural fields. Aquatic nutrient eutrophication can lead to loss of biodiversity, outbreaks of nuisance species, shifts in the structure of food chains, and impairment of fisheries. Because of aerial redistribution of various forms of nitrogen, agricultural intensification also would eutrophy many natural terrestrial ecosystems and contribute to atmospheric accumulation of greenhouse gases. These detrimental environmental impacts of agriculture can be minimized only if there is much more efficient use and recycling of nitrogen and phosphorus in agroecosystems. (+info)
(2/404) Nitrogen management and the future of food: lessons from the management of energy and carbon.
The food system dominates anthropogenic disruption of the nitrogen cycle by generating excess fixed nitrogen. Excess fixed nitrogen, in various guises, augments the greenhouse effect, diminishes stratospheric ozone, promotes smog, contaminates drinking water, acidifies rain, eutrophies bays and estuaries, and stresses ecosystems. Yet, to date, regulatory efforts to limit these disruptions largely ignore the food system. There are many parallels between food and energy. Food is to nitrogen as energy is to carbon. Nitrogen fertilizer is analogous to fossil fuel. Organic agriculture and agricultural biotechnology play roles analogous to renewable energy and nuclear power in political discourse. Nutrition research resembles energy end-use analysis. Meat is the electricity of food. As the agriculture and food system evolves to contain its impacts on the nitrogen cycle, several lessons can be extracted from energy and carbon: (i) set the goal of ecosystem stabilization; (ii) search the entire production and consumption system (grain, livestock, food distribution, and diet) for opportunities to improve efficiency; (iii) implement cap-and-trade systems for fixed nitrogen; (iv) expand research at the intersection of agriculture and ecology, and (v) focus on the food choices of the prosperous. There are important nitrogen-carbon links. The global increase in fixed nitrogen may be fertilizing the Earth, transferring significant amounts of carbon from the atmosphere to the biosphere, and mitigating global warming. A modern biofuels industry someday may produce biofuels from crop residues or dedicated energy crops, reducing the rate of fossil fuel use, while losses of nitrogen and other nutrients are minimized. (+info)
(3/404) Use of molecular and isotopic techniques to monitor the response of autotrophic ammonia-oxidizing populations of the beta subdivision of the class proteobacteria in arable soils to nitrogen fertilizer.
This study examined the effects of NH(4)NO(3) fertilizer on the size and activity of nitrifying, autotrophic, ammonia-oxidizing populations of the beta subdivision of the class Proteobacteria in arable soils. Plots under different long-term fertilizer regimes were sampled before and after NH(4)NO(3) additions, and the rates of nitrification were determined by (15)N isotopic pool dilution assays. Ammonia-oxidizing populations in the plots were quantified by competitive PCR assays based on the amoA and ribosomal 16S genes. Prior to fertilizer addition, ammonium concentrations and nitrification rates in the plots were comparatively low; ammonia-oxidizing populations were present at 10(4) to 10(5) gene copies g of soil(-1). Three days after the application of fertilizer, nitrification rates had risen considerably but the size of the ammonia-oxidizing population was unchanged. Six weeks after fertilizer treatment, ammonium concentrations and nitrification rates had fallen while the ammonia-oxidizing populations in plots receiving fertilizer had increased. The rapidity of the rise in nitrification rates observed after 3 days suggests that it results from phenotypic changes in the ammonia-oxidizing bacterial population. Associated increases in population sizes were only observed after 6 weeks and did not correlate directly with nitrifying activity. Phylogenetic analyses of PCR products from one of the plots revealed a population dominated by Nitrosospira-type organisms, similar to those prevalent in other soils. (+info)
(4/404) Nitrogen pollution: an assessment of its threat to amphibian survival.
The potential for nitrate to affect amphibian survival was evaluated by examining the areas in North America where concentrations of nitrate in water occur above amphibian toxicity thresholds. Nitrogen pollution from anthropogenic sources enters bodies of water through agricultural runoff or percolation associated with nitrogen fertilization, livestock, precipitation, and effluents from industrial and human wastes. Environmental concentrations of nitrate in watersheds throughout North America range from < 1 to > 100 mg/L. Of the 8,545 water quality samples collected from states and provinces bordering the Great Lakes, 19.8% contained nitrate concentrations exceeding those which can cause sublethal effects in amphibians. In the laboratory lethal and sublethal effects in amphibians are detected at nitrate concentrations between 2.5 and 100 mg/L. Furthermore, amphibian prey such as insects and predators of amphibians such as fish are also sensitive to these elevated levels of nitrate. From this we conclude that nitrate concentrations in some watersheds in North America are high enough to cause death and developmental anomalies in amphibians and impact other animals in aquatic ecosystems. In some situations, the use of vegetated buffer strips adjacent to water courses can reduce nitrogen contamination of surface waters. Ultimately, there is a need to reduce runoff, sewage effluent discharge, and the use of fertilizers, and to establish and enforce water quality guidelines for nitrate for the protection of aquatic organisms. (+info)
(5/404) Examination of slurry from cattle for pathogenic bacteria.
One hundred and eighty-seven samples of slurry from cattle were examined forthe presence of salmonellas, pathogenic leptospires and brucellas. Small numbers of salmonellas, generally less than 1/g., were isolated from 20 samples (11%). These were S. dublin (12), S. typhimurium (4), S. indiana (1), S. bredeney (1), S. cerro (1) and S. unnamed 4, 12:d:-(1). Leptospires were isolated from 56 samples (30%) but none was pathogenic for hamsters. No brucellas were isolated. The results of this survey are discussed in relation to the epidemiology of salmonellosis. (+info)
(6/404) The effect of storage in slurry on the virulence of Salmonella dublin.
The mouse was used as a model to determine whether storage of Salmonella dublin in slurry and in broth reduces the virulence of the organism. No reduction in virulence of S. dublin stored in slurry for 36 days or in maintenance broth for 70 days was observed. The disease hazard involved in pasture-spreading of slurry contaminated with salmonellas is related to factors other than virulence. (+info)
(7/404) Farming from a new perspective: remote sensing comes down to earth.
Farmers strive to increase the yield of their fields by adding nutrients and water to the land, and using pesticides to control insects and disease. In addition to bountiful harvests, the results of their endeavors may include elevated amounts of fertilizers in surface waters and aquifers and potential risk to themselves and their neighbors from exposure to pesticides. Precision agriculture is the use of modern information technologies such as geographic information systems, the global positioning system, and remote sensing from the air to reduce the environmental effects of these chemicals while enhancing the productivity of farming. By combining crop yield maps with soil survey maps and remote sensing output, farmers can identify areas that need more or less fertilizer, water, or pesticide. (+info)
(8/404) Survival of coliform bacteria in sewage sludge applied to a forest clearcut and potential movement into groundwater.
Anaerobically digested dewatered sludge (10 to 15 cm thick) was applied to a forest clearcut as a fertilizer source in northwest Washington on gravelly glacial outwash soil. This sludge is not microbiologically sterile and may contain pathogenic organisms. Fecal coliform bacterial counts in sludge applied in summer (July) fell from 1.08 X 10(5) to 358/g in 204 days and to 0/g in 267 days. Dieoff appeared more rapid in winter (January)-applied sludge, when colnts fell from 1.2 X 10(5) to 20/g in 162 days. Initial death rates were related to sludge temperature, moisture, pH, physical composition, and microbial competition. Aftergrowth of fecal coliforms occurred in warm summer and fall months, but counts were of similar magnitude to background levels in forest soils, where a maximum count of 54/g was recorded. Total coliform counts in fresh sludge ranged from 1.4 X 10(4) to 1.9 X 10(6)/g. Numbers stabilized at 10(3) to 10(4)/g in spring, fall, and summer, with lower numbers in winter. Both total and fecal bacteria moved from the sludge to the soil beneath, but few penetrated past the first 5 cm. The soil acts as an effective biological filter. Few fecal coliform bacteria were recorded in the groundwater, generally being less than 5/100 ml and mostly 0/100 ml. A maximum count of 52/100 ml was recorded. Groundwater contamination from vertical movement of potential pathogens appears unlikely, but hazards from surface runoff and direct handling in the first year may arise. (+info)