Column Installation Pre-Swaging Tools Optimize GC performance and reproducibility by ensuring a proper length of column into the inlet, time after time. For accurate results, the proper length of column must be inserted into. ABC Techno Lab is an Environmental Engineering Consultants in Chennai, India which carrying out EIA studies and obtaining Environmental clearance.We serve as. Soil Quality Assessment Strategies for Evaluating Soil Degradation in Northern Ethiopia. College of Agriculture, Aksum University- Shire Campus, 3. Shire, Ethiopia. 2Center for Development Research (ZEF), University of Bonn, Walter- Flex Street No. Bonn, Germany. Received 2. June 2. 01. 3; Revised 1. November 2. 01. 3; Accepted 2. November 2. 01. 3; Published 4 February 2. Soil fertility can be maintained when nutrients are efficiently recycled through the soil food web and soil-plant-animal system. Nutrient cycling is conveniently illustrated in diagrams that range from very simple (Fig. Cat Soil Compactors are designed with durability built in, ensuring maximum availability through multiple life cycles. With optimized performance and simplified serviceability, our machines allow you to operate more. Overview Objectives : Sorghum grown in India in the post-rainy season (Rabi) relies on residual soil moisture, and the crop is commonly exposed to terminal drought stress. Copyright . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Soil quality (SQ) degradation continues to challenge sustainable development throughout the world. 850-DS Dissolution Sampling Station The 850-DS Dissolution Sampling Station offers the latest capabilities for centralizing laboratory workflow of sample transfer, filtration and collection. By managing unattended dissolution. Manufacturer of Soil Testing Equipment - Sampling Auger, Direct Shear Apparatus, Soil Permeability Apparatus and CBR Apparatus offered by Biological Enterprises, Delhi, New Delhi, Delhi. Ammonia-oxidising archaea (AOA) and bacteria (AOB) are responsible for the rate limiting step in nitrification; a key nitrogen (N) loss pathway in agricultural systems. Altmetric: 18; Views: 888; Citations: 1; More detail. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant. Sarata Kumar Sahoo 1. One reason is that degradation indicators such as soil quality index (SQI) are neither well documented nor used to evaluate current land use and soil management systems (LUSMS). The objective was to assess and identify an effective SQ indicator dataset from among 2. SQ indexing method to evaluate soil degradation across the LUSMS in the Mai- Negus catchment of northern Ethiopia. Eight LUSMS selected for soil sampling and analysis included (i) natural forest (LS1), (ii) plantation of protected area, (iii) grazed land, (iv) teff (Eragrostis tef)- faba bean (Vicia faba) rotation, (v) teff- wheat (Triticum vulgare)/barley (Hordeum vulgare) rotation, (vi) teff monocropping, (vii) maize (Zea mays) monocropping, and (viii) uncultivated marginal land (LS8). Four principal components explained almost 8. LUSMS. LS1 had the highest mean SQI (0. PCA) dataset selection, while the lowest SQI (0. LS8. Mean SQI values for LS1 and LS8 using expert opinion dataset selection method were 0. Finally, a sensitivity analysis (S) used to compare PCA and expert opinion dataset selection procedures for various scoring functions ranged from 1. SQI to 2. 6. 3 for PCA- SQI. Therefore, this study concludes that a PCA- based SQI would be the best way to distinguish among LUSMS since it appears more sensitive to disturbances and management practices and could thus help prevent further SQ degradation. Introduction. Globally, declining in soil quality (SQ) has posed a tremendous challenge to increasing agricultural productivity, economic growth, and healthy environment . The underlying causes for SQ degradation are largely related to inappropriate land use and soil management, erratic and erosive rainfall, steep terrain, deforestation, and overgrazing . Most of the causes are resulted from a desperate attempt by farmers to increase production for the growing population which aggravate SQ degradation more in the developing countries, which mainly depend on natural resources (agriculture) . Misuse of natural resources that leads to degradation can also be stimulated by socioeconomic and political issues, for example, land tenure, capital, and infrastructure . SQ degradation by soil erosion such as soil nutrient depletion and changes in soil physical indicators is largely recognized as a principal cause aggravated by the effect of inappropriate land use and soil management in the developing countries like Ethiopia . In normal conditions, the soil can maintain equilibrium by pedogenetic processes . However, this equilibrium is easily disturbed by anthropogenic activities (e. In order to make sound decisions regarding sustainable land use systems, knowledge of SQ related to different land use scenarios is essential . It is therefore most important to assess SQ degradation of different land use and soil management systems using soil quality index (SQI) since many of the factors that influence sustainable productivity are related to SQ. Information on SQI can support to further prioritization and then device management strategies that improve soil resources sustainably . To do so, applying the concept of SQI is desirable as individual soil properties in isolation may not be sufficient to quantify changes in SQ related to land use and soil management systems . In line to this, many studies reported that indexing SQ indicators based on a combination of soil properties could better reflect the status of SQ degradation as compared to individual parameters . Previous studies reported that different methods of minimum dataset selection (MDS), scoring, and SQ indexing have been applied but SQI results varied even for the same conditions . The most widely reported MDS methods of SQ indicators are expert opinion and statistical tools (e. PCA)) . An expert can generate a list of appropriate SQ indicators on the basis of ecosystem processes and functions and other decision rules such as management goals for a site associated with soil functions as well as other site- specific factors, like region or crop sensitivity as selection criteria . Studies elsewhere compared the two scoring methods to represent soil system function but the value of nonlinear scoring method was reported higher than the linear method . There are different types of linear and nonlinear scoring functions, even though none of the previous studies have evaluated them all simultaneously . Different SQ indexing methods have been also used by different researchers . The same authors have reported that there are differences in SQI values among the various SQ indexing methods (e. Despite the fact that there is diversity in data selection, scoring, and SQ indexing methods, previous studies have limitation in evaluating the methods using the same data simultaneously in a similar field conditions. Regardless of the above limitation, having SQI of long- term land use and soil management systems is necessary in order to locate areas to be carefully managed for sustainable development. The use of site- specific SQI can help planners and decision makers to evaluate which land use and management system is most sustainable and vice- versa in a given situation . These authors also noted that SQI can reflect the extent of SQ degradation and thereby give support to suggest appropriate remedial measures such as optimum fertilizer rates and planning of other suitable land management practices considering potentials and constraints of different fields at large scale such as a catchment. In general, SQI is a useful assessment tool that may help move soil conservation and resource management beyond assessments of soil erosion and changes in productivity . SQI can thus provide the necessary information for planners and decision makers to make informed decisions against SQ degradation using the introduction of appropriate interventions. Despite such importance of SQI in combating SQ degradation, only few studies have been reported in relation to various land use and soil management systems. This indicated that research on SQI has been mostly neglected for unknown reasons, with the most probable reason which could be technical and financial limitations. Many approaches assessing SQ degradation using the concept of SQI have been already developed and applied elsewhere . In this study, such concepts are adopted and evaluated to narrow the knowledge/information gap of SQI across different land use and soil management systems in the northern Ethiopia. The objective of this study was to assess and identify an effective SQ indicator dataset among 2. SQ indexing method to evaluate soil degradation across the LUSMS in the Mai- Negus catchment of northern Ethiopia. Materials and Methods. Study Area. This evaluation was conducted in the Mai- Negus catchment in Tigray regional state, northern Ethiopia (Figure 1). The catchment covers an area of 1. Land use is dominantly arable with teff (Eragrostis tef) being the primary crop on > 8. The remainder of the catchment is pasture with scattered patches of mixed tree, bush, and shrub cover. The major rock types are lava pyroclastic and metavolcanic. According to FAO- UNESCO Soil Classification System, soils are dominantly Leptosols at very steep positions, Cambisols on middle to steep slopes, and Vertisols on flat areas . Annual rainfall averages 7. Mean annual temperature was 2. Selection of Land Use and Soil Management Systems. Eight land use and soil management systems (LUSMS) were selected on the basis of three steps. First, information on historical and existing LUSMS in the catchment was collected and described. Soil sampling units were then identified across each LUSMS. Finally, composite soil samples were collected, processed, and analyzed for several SQ indicators using standard laboratory procedures. The first step is described below, with details for the second and third steps given in Sections 2. Field reconnaissance surveys and informal group discussions were conducted in June 2. The six farmers were selected purposively because the large group size made it impractical for all the household heads to participate and doing so would have been problematic for discussion and consensus building. The dominant cropping history and soil management practices for each LUSMS were identified and described by the team. In addition, terrain characteristic and soil factors were documented for each rain- fed agricultural LUSMS. All eight LUSMS were selected as much as possible to be from similar soil type (Cambisols) and a range in slope gradient in the catchment. Topographical characteristics of each sampling units are presented in Table 1. Table 1: Topographic characteristics of each sampling unit in the eight LUSMS selected for soil quality assessment within the Mai- Negus catchment in northern Ethiopia. Based on land use information acquired in the study, eight LUSMS that represent the best and worst management practices being used throughout the study catchment were identified and are described (Table 2). Soil contamination - Wikipedia, the free encyclopedia. Excavation showing soil contamination at a disused gasworks. Soil contamination or soil pollution as part of land degradation is caused by the presence of xenobiotic (human- made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals, or improper disposal of waste. The most common chemicals involved are petroleumhydrocarbons, polynuclear aromatic hydrocarbons (such as naphthalene and benzo(a)pyrene), solvents, pesticides, lead, and other heavy metals. Contamination is correlated with the degree of industrialization and intensity of chemical usage. The concern over soil contamination stems primarily from health risks, from direct contact with the contaminated soil, vapors from the contaminants, and from secondary contamination of water supplies within and underlying the soil. Developing countries tend to be less tightly regulated despite some of them having undergone significant industrialization. Soil pollution can be caused by the following (non- exhaustive list!): The most common chemicals involved are petroleumhydrocarbons, solvents, pesticides, lead, and other heavy metals. In a wider sense, genetically modified plants (GMP) can count as a risk factor for soils, because of their potential to affect the soil fauna. Coal naturally concentrates lead and zinc during its formation, as well as other heavy metals to a lesser degree. When the coal is burned, most of these metals become concentrated in the ash (the principal exception being mercury). Coal ash and slag may contain sufficient lead to qualify as a . In addition to lead, coal ash typically contains variable but significant concentrations of polynuclear aromatic hydrocarbons (PAHs; e. These PAHs are known human carcinogens and the acceptable concentrations of them in soil are typically around 1 mg/kg. Coal ash and slag can be recognised by the presence of off- white grains in soil, gray heterogeneous soil, or (coal slag) bubbly, vesicular pebble- sized grains. Treated sewage sludge, known in the industry as biosolids, has become controversial as a . As it is the byproduct of sewage treatment, it generally contains more contaminants such as organisms, pesticides, and heavy metals than other soil. The volume is expected to double to 1. This has good agricultural properties due to the high nitrogen and phosphate content. In 1. 99. 0/1. 99. A pesticide may be a chemical substance, biological agent (such as a virus or bacteria), antimicrobial, disinfectant or device used against any pest. Pests include insects, plant pathogens, weeds, mollusks, birds, mammals, fish, nematodes (roundworms) and microbes that compete with humans for food, destroy property, spread or are a vector for disease or cause a nuisance. Although there are benefits to the use of pesticides, there are also drawbacks, such as potential toxicity to humans and other organisms. They are similar to auxins and most are biodegradable by soil bacteria. However, one group derived from trinitrotoluene (2: 4 D and 2: 4: 5 T) have the impurity dioxin, which is very toxic and causes fatality even in low concentrations. Another herbicide is Paraquat. It is highly toxic but it rapidly degrades in soil due to the action of bacteria and does not kill soil fauna. The insects damage not only standing crops but also stored ones and in the tropics it is reckoned that one third of the total production is lost during food storage. As with fungicides, the first insecticides used in the nineteenth century were inorganic e. Paris Green and other compounds of arsenic. Nicotine has also been used since the late eighteenth century. Organochlorines include DDT, Aldrin, Dieldrin and BHC. They are cheap to produce, potent and persistent. DDT was used on a massive scale from the 1. Then usage fell as the harmful environmental effects were realized. It was found worldwide in fish and birds and was even discovered in the snow in the Antarctic. It is only slightly soluble in water but is very soluble in the bloodstream. It affects the nervous and endocrine systems and causes the eggshells of birds to lack calcium causing them to be easily breakable. It is thought to be responsible for the decline of the numbers of birds of prey like ospreys and peregrine falcons in the 1. As it has low water solubility, it tends to stay at the water surface, so organisms that live there are most affected. DDT found in fish that formed part of the human food chain caused concern, but the levels found in the liver, kidney and brain tissues was less than 1 ppm and in fat was 1. However, DDT was banned in the UK and the United States to stop the further buildup of it in the food chain. Organophosphates, e. Parathion is highly toxic, methyl- parathion is less so and Malathion is generally considered safe as it has low toxicity and is rapidly broken down in the mammalian liver. This group works by preventing normal nerve transmission as cholinesterase is prevented from breaking down the transmitter substance acetylcholine, resulting in uncontrolled muscle movements. There is little published evidence on this type of contamination largely because of restrictions placed by Governments of many countries on the publication of material related to war effort. However, mustard gas stored during World War II has contaminated some sites for up to 5. This tends to result in the development of pollution- related diseases. Health consequences from exposure to soil contamination vary greatly depending on pollutant type, pathway of attack and vulnerability of the exposed population. Chronic exposure to chromium, lead and other metals, petroleum, solvents, and many pesticide and herbicide formulations can be carcinogenic, can cause congenital disorders, or can cause other chronic health conditions. Industrial or man- made concentrations of naturally occurring substances, such as nitrate and ammonia associated with livestock manure from agricultural operations, have also been identified as health hazards in soil and groundwater. Mercury and cyclodienes are known to induce higher incidences of kidney damage and some irreversible diseases. PCBs and cyclodienes are linked to liver toxicity. Organophosphates and carbomates can induce a chain of responses leading to neuromuscular blockage. Many chlorinated solvents induce liver changes, kidney changes and depression of the central nervous system. There is an entire spectrum of further health effects such as headache, nausea, fatigue, eye irritation and skin rash for the above cited and other chemicals. At sufficient dosages a large number of soil contaminants can cause death by exposure via direct contact, inhalation or ingestion of contaminants in groundwater contaminated through soil. The overall aim of the project is to work up guidance that should be useful to Scottish Local Authorities in assessing whether sites represent a significant possibility of significant harm (SPOSH) to human health. It is envisaged that the output of the project will be a short document providing high level guidance on health risk assessment with reference to existing published guidance and methodologies that have been identified as being particularly relevant and helpful. The project will examine how policy guidelines have been developed for determining the acceptability of risks to human health and propose an approach for assessing what constitutes unacceptable risk in line with the criteria for SPOSH as defined in the legislation and the Scottish Statutory Guidance. Ecosystem effects. These changes can manifest in the alteration of metabolism of endemic microorganisms and arthropods resident in a given soil environment. The result can be virtual eradication of some of the primary food chain, which in turn could have major consequences for predator or consumer species. Even if the chemical effect on lower life forms is small, the lower pyramid levels of the food chain may ingest alien chemicals, which normally become more concentrated for each consuming rung of the food chain. Many of these effects are now well known, such as the concentration of persistent DDT materials for avian consumers, leading to weakening of egg shells, increased chick mortality and potential extinction of species. Contaminants typically alter plant metabolism, often causing a reduction in crop yields. This has a secondary effect upon soil conservation, since the languishing crops cannot shield the Earth's soil from erosion. Some of these chemical contaminants have long half- lives and in other cases derivative chemicals are formed from decay of primary soil contaminants. Various technologies have been developed for remediation of oil- contaminated soil/ sediments . This technique also applies to dredging of bay muds containing toxins. Aeration of soils at the contaminated site (with attendant risk of creating air pollution)Thermal remediation by introduction of heat to raise subsurface temperatures sufficiently high to volatize chemical contaminants out of the soil for vapour extraction. Technologies include ISTD, electrical resistance heating (ERH), and ET- DSPtm. Bioremediation, involving microbial digestion of certain organic chemicals. Techniques used in bioremediation include landfarming, biostimulation and bioaugmentatingsoil biota with commercially available microflora. Extraction of groundwater or soil vapor with an active electromechanical system, with subsequent stripping of the contaminants from the extract. Containment of the soil contaminants (such as by capping or paving over in place). Phytoremediation, or using plants (such as willow) to extract heavy metals. Mycoremediation, or using fungus to metabolize contaminants and accumulate heavy metals. By country. EPA Region 3 Risk Based Concentrations (U. S. EPA RBCs) and National Environment Protection Council of Australia Guideline on Investigation Levels in Soil and Groundwater. People's Republic of China.
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