High tunnels, or unheated plastic greenhouses, are becoming increasingly popular among organic vegetable growers across the United States. However, the intensive production typical of these systems presents soil health challenges, including salinization due to high fertilizer or compost inputs coupled with lack of rainfall to leach salts. Legume cover crops may improve soil health in high tunnels by reducing the need for external inputs, while adding organic matter. We tested the soil health effects of a winter hairy vetch (Vicia villosa Roth) cover crop used to replace fertilizer N in an organic tomato cropping system in high tunnels. Studies were replicated across three sites differing in climate and soil type (Kansas, Kentucky, and Minnesota) over three years. We measured vetch cover crop effects on a suite of soil health indicators, including potentially mineralizable nitrogen (PMN), permanganate oxidizable carbon, and microbial biomass. Preliminary results suggest that vetch effects on PMN were highly variable. Soil mineral N, meanwhile, was often lower in the vetch treatment than in a fertilized control, both in spring and in fall. While further work on vetch effects on crop yields is needed, our results suggest that even legume cover crops such as vetch have the potential to reduce nitrate leaching.
GA Al Omran, AA Noaimi, Z Al Madfai, H Al Hamamy, Journal of the Faculty of Medicine Baghdad, 2012
Recently, young people have shown a desire to keep cats as pets, despite being threatened with health problems including toxoplasmosis. Therefore, the current study was aimed to detect toxoplasmosis infections among of volunteers students as well as spreading health awareness among students and knowledge about the importance of this disease. Prevalence rate and effects of liver functions were tested by measured levels of Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT) enzymes while the OnSiteToxo IgG/IgM combo rapid test was used in the diagnosis of the disease. The blood samples were collected from 76 volunteers (35 male and 41 female). The results showed that, the total percentage of infections was 27.6% and all infect
... Show MoreA metal mandrel was designed for manufacturing the cathodes of high power electron tube ( Tetrode ) used in broadcasting transmitting tubes type TH558 and CQS200.The cathodes were manufactured in the present work from thoriated tungsten wires ( 2? ThO2- W) with different diameters .These cathodes were carbonized in sequences of processes to determine the carbonization parameters (temperature, pressure, time, current and voltage).Then the carbonized cathodes dimension were accurately measured to determine the deviation due to the high temperature distortion effect at about 1800°C .the distorted cathodes due to the carbonization process was treated when it was subjected inside the vacuum chamber and heat treated again .The carbonized cat
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The response of floating stone columns of different lengths to diameter ratio (L/D = 0, 2, 4, 6, 8, and 10) ratios exposed to earthquake excitations is well modeled in this paper. Such stone column behavior is essential in the case of lateral displacement under an earthquake through the soft clay soil. ABAQUS software was used to simulate the behavior of stone columns in soft clayey soil using an axisymmetric finite element model. The behavior of stone column material has been modeled with a Drucker-Prager model. The soft soil material was modeled by the Mohr-Coulomb failure criterion assuming an elastic-perfectly plastic behavior. The floating stone columns were subjected to the El Centro earthquake, which had a magnitude of 7.1 an
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Trickle irrigation is one of the most conservative irrigation techniques since it implies supplying water directly on the soil through emitters. Emitters dissipate energy of water at the end of the trickle irrigation system and provide water at emission points. The area wetted by an emitter depends upon the discharge of emitter, soil texture, initial soil water content, and soil permeability. The objectives of this research were to predict water distribution profiles through different soils for different conditions and quantify the distribution profiles in terms of main characteristics of soil and emitter. The wetting patterns were simulated at the end of each hour for a total time of application of 12 hrs, emitter disch
... Show MoreActivities associated with mining of uranium have generated significant quantities of waste materials containing uranium and other toxic metals. A qualitative and quantitative study was performed to assess the situation of nuclear pollution resulting from waste of drilling and exploration left on the surface layer of soil surrounding the abandoned uranium mine hole located in the southern of Najaf province in Iraq state. To measure the specific activity, twenty five surface soil samples were collected, prepared and analyzed by using gamma- ray spectrometer based on high counting efficiency NaI(Tl) scintillation detector. The results showed that the specific activities in Bq/kg are 37.31 to 1112.47 with mean of 268.16, 0.28 to 18.57 with
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One of the most important environmental issues is the responsible effective and economic treatment of drilling waste especially oily waste.
In this research two fungal isolates named Pleurotus ostreatus and Trichoderma harzianum were chosen for the first time to treat biologically the oily drilled cuttings contaminated with diesel which resulted from drilling oil wells use oil based muds (OBMs).
The results showed that the fungi under study utilized the hydrocarbon of contaminated soil as a source of nutrient and growth and that both fungi can be considered hydrocarbon degrading microorganisms. The used biotreatment is cost effective process since most of the materials used in the cultivation and growth of the present fungi were av
The study area soils suffer from several problems appear as tkhesvat and cracks in the roads and waterlogging which reduces the susceptibility of soil to withstand pressure, this study was conducted on the soil of the Karkh district based on field study that included (6) samples of soil physical analyses contain different ratios of (mud, sand, silt) as percentages (52%, 45%, 3 #) respectively, and liquidity limit rate (39%) Stroke rate plasticity was (20.6%) The rate coefficient of plasticity total (19.2%)0