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Eşfahān, Iran

Roudgarmi P.,Agricultural Research
Journal of Food, Agriculture and Environment | Year: 2011

The environmental sciences can be constituted based on some branches of natural science, social science and applied science. Solving environmental problems requires integration of expertise in some academic disciplines. This challenge stems from the essence of environmental sciences because these fields have an interdisciplinary nature. The most academic disciplines have specialized research methodology, but environmental sciences need some research methodologies. The aim of this paper is to present qualitative research methodology for solving environmental problems and respond to expected questions through gathering and inferring from the results of various qualitative studies. In this paper, various qualitative research approaches used in the studies are discussed. Using qualitative research is inevitable under some conditions. Based on presented cases, the capability of qualitative research in environmental areas is explained. Qualitative research can respond to many questions in environmental investigations and professional reports. Qualitative research approaches may be used to respond to the questions arisen in preparation of professional reports such as Environmental Impact Statements, Strategic Environmental Assessment reports and Protected Area Management Plan. This research methodology has the advantage that it can be performed with minimum planning and equipment whereas some quantitative and experimental methods in environmental studies are time-consuming, complex and actually impractical in certain cases. Source


News Article
Site: http://phys.org/biology-news/

Rangelands are critical resources, but in the United States and elsewhere they are being degraded by invasive weeds, wildfires, droughts, mining, and other disturbances. Climate change is expected to increase the frequency and severity of droughts and wildfires, which may degrade rangelands even more and open the door to invasive plants. "Rangelands provide key ecological services, but they are being threatened like never before," says Philip A. Fay, an Agricultural Research Service ecologist in Temple, Texas. Fay led one of two ARS studies focused on understanding the impacts of such threats to rangeland health and finding optimal ways to restore degraded rangelands. Conducting realistic, large-scale studies focused on restoring degraded rangelands can be prohibitively expensive. Matthew J. Rinella, an ARS rangeland management specialist in Miles City, Montana, reviewed restoration reports filed by mining companies on 169 former coal mining fields that were subjected to various restoration efforts between 1992 and 2009. Rinella's team also quantified shrubs on the fields. The approach allowed the team to identify effective shrub-restoration strategies while avoiding the expense of conducting large-scale studies. Shrubs are important because they provide critical habitat for mule deer, pronghorn, elk, and the threatened greater sage-grouse. "Additionally, in some ecosystems, shrubs are a critical source of livestock forage, so learning to restore shrubs is important for global food security," Rinella says. The results, published in Ecological Applications (June 2015), showed that grass-seeding rates were a critical factor. When grasses were sown at high rates, shrubs were rapidly choked out before they could become established. Conversely, sowing grasses at low rates allowed shrubs to persist and reach deep into soil layers, where they could access water and nutrients inaccessible to more shallow-rooted grasses. The results also showed that grasses developed well in the long run whether their seeds, which can be expensive, were sown at high or low rates. The results should be useful to mining companies, oil and gas companies, and government agencies working to improve degraded rangelands. In his study, Fay developed a unique global snapshot of rangeland dynamics by examining the effects of nitrogen and other nutrients on rangeland productivity at sites around the world. He and his colleagues applied nitrogen, phosphorus, and potassium mixed with micronutrients to 42 sites in 8 countries on 5 continents. Each site received the same proportions of the nutrients at the start of each growing season. The researchers harvested the grass each year, calculated the amount of biomass produced, and after 5 years analyzed the effects of the nutrients on the productivity of native and cultivated grasses and forbs. The sites were part of an established "Nutrient Network" of rangelands studied by international teams of scientists. They were located across a broad range of elevations, temperatures, precipitation patterns, soils, and growing seasons. "Giving the same treatments to such diverse sites allows us to see implications that are global in scale, which means the results are that much more robust and significant," Fay says. They found that nutrient availability was a limiting factor to rangeland productivity at 31 of the 42 sites and that adding multiple nutrients often increased rangeland productivity by as much as 65 percent. Why nutrients were not limiting factors at 11 sites may be the focus of future studies, Fay says. They also were surprised to find that phosphorus and potassium were major factors in rangeland productivity on all five continents. "We didn't expect to see such widespread effects from nutrient combinations that included phosphorus or potassium, because these two nutrients have been less well studied than nitrogen," Fay says. Previous studies have demonstrated the effects of applying nitrogen fertilizers on rangelands, but the results of Fay's study were among the first to show the importance of phosphorus and potassium in rangeland health at such widely diverse sites. The results, published in Nature Plants (July 2015), should lead to a better understanding of the factors that influence rangeland health and the potential impacts of future land use changes. Explore further: Livestock Can Help Rangelands Recover from Fires More information: Matthew J. Rinella et al. High precipitation and seeded species competition reduce seeded shrub establishment during dryland restoration, Ecological Applications (2015). DOI: 10.1890/14-1110.1


News Article | September 1, 2016
Site: http://www.rdmag.com/rss-feeds/all/rss.xml/all

Populations of New World screwworm flies - devastating parasitic livestock pests in Western Hemisphere tropical regions - could be greatly suppressed with the introduction of male flies that produce only males when they mate, according to new research from North Carolina State University, the USDA's Agricultural Research Service, the Panama-United States Commission for the Eradication and Prevention of Screwworm (COPEG) and the Smithsonian Tropical Research Institute. Withholding tetracycline in the larval diet essentially means "It's a boy" when the genetically modified male flies successfully mate with females in the field, says Max Scott, an NC State entomologist who is the corresponding author of a paper describing the research. "Genetic suppression of a pest population is more efficient if only males survive, so we manipulated screwworm genes to promote a female-lethal system that works when a common antibiotic is not provided at larval stages," Scott said. "If we feed the larvae the antibiotic both male and female survive and are as fit as the wild type strain." The study shows that the genetically modified males both compete well for the attention of fertile females and mate successfully with fertile females. The genetically modified flies also do not mate with other very closely related fly species. New World screwworm flies (Cochliomyia hominivorax) parasitize warm-blooded animals in the Western Hemisphere tropics and sub-tropics, causing massive financial and animal losses. The flies were eradicated from North and Central America years ago using the sterile insect technique, which has resulted in annual savings of more than $1 billion per year. However, the flies continue to wreak havoc across South America and some Caribbean islands. Scott says that a sterile insect technique has been used to keep the South American flies at bay. This technique involves irradiating both male and female flies to make them sterile and then releasing them - in an area between the Panama Canal and Colombia - to mate with fertile flies in order to prevent screwworm re-introduction to Central and North America. "This is a bit inefficient, as sterile males will mate with sterile females, which is totally unnecessary," Scott says. "Releasing only males, would cut down on the costs of rearing sterile female flies and should significantly increase the efficiency of the suppression program. Plus, it would take fewer resources to begin screwworm eradication program in other afflicted areas, like the west coast of South America, for example." In addition, the technology should be easily transferable to other flies that are pests of livestock such as the Old World screwworm. Scott added that COPEG will now evaluate one of the genetically modified screwworm fly lines. That commission has worked to prevent the reintroduction of the pest into North and Central America and is responsible for the current sterile insect technique program. All of the genetically modified strains were developed within the COPEG biosecure facility in Panama, which will facilitate incorporation of the strains into the ongoing operational program. The study was published online in the journal BMC Biology. Funding was provided by USDA's Agricultural Research Service and its National Institute of Food and Agriculture BRAG program, COPEG and NC State.


News Article
Site: http://phys.org/technology-news/

Now, a team of Agricultural Research Service scientists in Wyndmoor, Pennsylvania, has made key advances in a process that produces a crude liquid called "bio-oil" from agricultural waste. The crude bio-oil is produced by pyrolysis, a process that involves chemical decomposition of plant and other organic matter using very high heat. The modified technique is called "tail-gas reactive pyrolysis" (TGRP). It holds promise for processing and improving the bio-oil, which is ultimately processed into finished biofuel. The Energy Independence and Security Act of 2007 calls for a minimum of 36 billion gallons of advanced biofuels to be produced in the U.S. by the year 2022. This effort will require, in part, the development of a new industry that produces 21 billion gallons of new biofuels based on non-food sources. "Ideally, the biofuels added to gasoline would be identical to fuels produced at petroleum refineries," says chemical engineer Yaseen Elkasabi. The research team, which includes Elkasabi, is headed by chemical engineer Akwasi Boateng with chemist Charles Mullen, and engineers Neil Goldberg and Mark Schaffer, in the Sustainable Biofuels and Coproducts Unit at the ARS Eastern Regional Research Center. Raw material called "biomass" is the basis for producing biofuel, and it includes non-food-grade plant matter procured from agricultural or household waste. "We are using crop and forestry residue, such as wood and switchgrass, and also animal manures to produce bio-oils at an accelerated rate using a new high-output, mobile processing unit," says Mullen. "Rather than shipping large amounts of agricultural waste to a refinery plant at a cost, the mobile reactor allows us to convert the biomass into a more energy-dense bio-oil right on the farm." The goal of using TGRP on the farm is to yield a higher quality bio-oil that is more marketable to biofuel producers than bio-oil made from traditional pyrolysis methods. Construction of the mobile unit was funded by a Biomass Research and Development Initiative grant from USDA's National Institute of Food and Agriculture. At petroleum refineries, distillation is a process used for preparing crude oils into finished fuels. But traditional petroleum refineries are not equipped to distill crude pyrolysis oil because it is highly acidic and has high oxygen content, making it corrosive and thermally unstable. Petroleum is naturally deoxygenated. While crude bio-oil can be deoxygenated by adding a catalyst, that approach is expensive and complex. The ARS team's studies have shown that the new TGRP process provides bio-oils that are similar in composition and properties to those produced by adding the catalyst. "The quality of TGRP deoxygenated liquids is equal to or better than the bio-oil produced by catalytic pyrolysis," says Elkasabi. "TGRP is an important step toward the ultimate goal of producing cleaner bio-oils that can be distilled at existing petroleum refineries."


News Article
Site: http://www.treehugger.com/feeds/category/science/

I recently rediscovered my oscillating or scuffle hoe, which had been tucked away in our basement for way too long. And now I am wondering how I survived without it all last summer. Basically, a sharp hooped blade on the end of a long stick, these beauties allow you to easily weed large areas without bending over by simply dragging and/or pushing the end blade along just under the soil surface, slicing through plant stems and severing them from their roots. I got mine at the local garden store—but there's an even greener option for those of you who don't mind doing a little work: You can simply make your own. And all it takes is a few easy to scavenge items: 1) A bamboo or giant grass pole, or wooden dowel (about the full length from your toes to the tip of your fingers if you hold them above your head). 2) Some lengths of steel strapping, typically used to hold heavy cargo in place (this can easily be salvaged from dumpsters) 3) Some bicycle inner tubes To be specific, this DIY version, created by Dr. Eric Brennan—a scientist at the United States Department of Agriculture (Agricultural Research Service), ORGANIC research program in Salinas, California—doesn't appear to have the angled blade of a scuffle hoe, which adjusts slightly to maintain it's ideal cutting angle. But that doesn't appear to be slowing Brennan down when it comes to weeding. In fact, the description on his YouTube channel claims this design beats out any of the standard commercialized designs that are out there. Anyone tried making one of these yet?

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