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Estimating erosion in a riverine watershed bayou liberty-tchefuncta river in louisiana 总被引:1,自引:0,他引:1
Martin A Gunter JT Regens JL 《Environmental science and pollution research international》2003,10(4):245-250
GOAL, SCOPE, BACKGROUND: Sheet erosion from agricultural, forest and urban lands may increase stream sediment loads as well as transport other pollutants that adversely affect water quality, reduce agricultural and forest production, and increase infrastructure maintenance costs. This study uses spatial analysis techniques and a numerical modeling approach to predict areas with the greatest sheet erosion potential given different soils disturbance scenarios. METHODS: A Geographic Information System (GIS) and the Universal Soil Loss Equation (USLE) were used to estimate sheet erosion from 0.64 ha parcels of land within the watershed. The Soil Survey of St. Tammany Parish, Louisiana was digitized, required soil attributes entered into the GIS database, and slope factors determined for each 80 x 80 meter parcel in the watershed. The GIS/USLE model used series-specific erosion K factors, a rainfall factor of 89, and a GIS database of scenario-driven cropping and erosion control practice factors to estimate potential soil loss due to sheet erosion. RESULTS AND DISCUSSION: A general trend of increased potential sheet erosion occurred for all land use categories (urban, agriculture/grasslands, forests) as soil disturbance increases from cropping, logging and construction activities. Modeling indicated that rapidly growing urban areas have the greatest potential for sheet erosion. Evergreen and mixed forests (production forest) had lower sheet erosion potentials; with deciduous forests (mostly riparian) having the least sheet erosion potential. Erosion estimates from construction activities may be overestimated because of the value chosen for the erosion control practice factor. CONCLUSIONS: This study illustrates the ease with which GIS can be integrated with the Universal Soil Loss Equation to identify areas with high sheet erosion potential for large scale management and policy decision making. RECOMMENDATIONS: The GIS/USLE modeling approach used in this study offers a quick and inexpensive tool for estimating sheet erosion within watersheds using publicly available information. This method can quickly identify discrete locations with relatively precise spatial boundaries (approximately 80 meter resolution) that have a high sheet erosion potential as well as areas where management interventions might be appropriate to prevent or ameliorate erosion. 相似文献
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不同措施在防治山地果园水土流失及面源污染中的应用研究 总被引:3,自引:0,他引:3
通过施用生物毯、生物带和秸秆覆盖3种措施,模拟人工降雨,测定山地果园的水土流失量,比较不同措施在防治山地果园水土流失中的效果.结果表明,在降雨强度为1.33 mm/min时,与对照相比生物毯和秸秆覆盖能减少50%以上的氮磷流失量,生物带减少氮磷流失量也达到30%以上;在降雨强度为2.33 mm/min时,秸秆覆盖防治水土流失的效果最好;在高降雨强度(2.33mm/min)时,各种措施防治效果降低,但效果仍然明显,对磷的防治效果好于对氮的防治效果,与对照相比生物毯能减少44.5%的磷流失量.山地果园水土流失相当严重,施用生物毯和秸秆覆盖能有效防治山地果园的面源污染. 相似文献
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本文结合GIS和流域土壤侵蚀模型,对流域单次降雨侵蚀过程进行动态模拟研究。首先概述土壤侵蚀模型与GIS结合的三种方式和特点;其次介绍地理信息系统PCRaster 的空间动态模型语言及其表达方法、命令函数和动态模型的逻辑组成,以及使用该语言实现的与GIS完全结合的流域水文和土壤侵蚀动态模型- LISEM 模型;最后分析用PCRaster 系统和LISEM 模型对黄土高原小流域次降雨过程进行动态模拟的实验结果,认为模型计算的总径流量和总土壤流失量具有较高的精度,模拟的径流过程线符合黄土高原小流域超渗产流的实际情况 相似文献
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Barbro M. Gullvåg Hartmut Frank Yrjü Norokorpi 《Environmental science and pollution research international》1996,3(3):159-162
The study has been performed in a supposedly clean-air region of a Northern Finnish forest with a homogeneous stand of Scots pine. Stomatal epicuticular wax layer erosion is described using a classification system of five erosion stages. The percentage of stomatal wax within each erosion stage is calculated and the results are treated statistically, which makes the morphological study of the needle surface semi-quantitative. Severe wax degradation has already been found in the current year, increasing with the age of the needles. In this area, the wax layer erosion is correlated with secondary air pollutants, as analyses have shown high trichloroacetate (TCA) levels in needles from the same trees. The wax layer analyses are in accordance with earlier findings which have demonstrated differences in tolerance to TCA. 相似文献
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Lance D. Yarbrough 《Environmental Forensics》2014,15(3):244-255
The consequences of erosion and subsequent sedimentation of lakes and streams are many and widespread. The natural process of erosion can be accelerated by land cover changes with an increase in areas of impervious surfaces. Sediment is continually being transported along all streams in nature and can come from anywhere in the watershed. Lakes slow the rate of velocity of the water and allow the entrained sediment to settle and accumulate. When sediment impacts water impoundments, legal actions may result. Even with evidence of specific sediment release, the forensic analysis may not be an open-and-shut case. The author presents a method to investigate the validity of a legal claim of a sediment-impacted lake at the outfall of a mixed rural/urban watershed. By combining land use change, soils, elevation and precipitation data, a maximum possible annual sediment loss was approximately 154 tonne per hectare (15.4 kg/m2). Lacking evidence of specific historic events of erosion and subsequent sedimentation, this method provides an equitable means of determining compensatory damages. Using aerial and satellite imagery provided historical evidence of land cover change and examples of significant erosion in the watershed and not named in the lawsuit. The focus of the litigation started with the property adjoining the effected lake. The analysis provides a method to investigate erosion and subsequent sedimentation claims at a watershed-scale. 相似文献
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Environmental monitoring of spatial-temporal changes using remote sensing and GIS techniques in the Abandoned Yellow River Delta coast, China 总被引:1,自引:0,他引:1
《国际环境与污染杂志》2011,45(4):327-341
On the basis of remote sensing and GIS techniques, the Landsat data obtained in 1978, 1987 and 2000 were used to examine coastline changes in the Abandoned Yellow River (AYR) Delta in China. The coastal land lost and gained illustrations were derived from the extracted coastlines, the rates of coastal change were estimated, and the coastal parts that experienced the biggest changes were identified. The results illustrated that the erosion rates of the AYR Delta coast decreased during 1978-2000 while the erosion effect remained strong. The spatial-temporal changing patterns of the northern, central and southern coastal parts in the study area were characterised by slow erosion, erosion and dynamic balance of erosion/accretion. 相似文献
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Phosphorus losses from arable land need to be reduced to prevent eutrophication of surrounding waters. Owing to the high spatial variability of P losses, cost-effective countermeasures need to target parts of the catchment that are most susceptible to P losses. Field surveys identified critical source areas for overland flow and erosion amounting to only 0.4–2.6 % of total arable land in four different catchments in southern Sweden. Distributed modelling using high-resolution digital elevation data identified 72–96 % of these observed erosion and overland flow features. The modelling results were also successfully used to predict occurrence of overland flow and rill and gully erosion in a catchment in central Sweden. Such exact high-resolution modelling allows for accurate placement of planned countermeasures. However, current legislative and environmental subsidy programmes need to change their approach from income-loss compensation to rewarding high cost effectiveness of implemented countermeasures. 相似文献
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John S. Evans Douglas W. Cooper 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1298-1303
Open sources are those stationary sources of air pollution too great in extent to be controlled through enclosure or ducting. Open sources of atmospheric particles include: wind erosion, tilling, and prescribed burning of agricultural cropland; surface mining and wind erosion of tailings piles; vehicular travel on both paved and unpaved roads; construction site activity; and forest fires. It is estimated that in 1976 the total open source emissions of particles in the U.S. amounted to over 580 × 106 ton. These estimates indicate that emissions from the two largest open source classes, travel on unpaved roads and agricultural wind erosion, accounted for 86% of this total. The open source emissions in ten states (AZ, CA, KS, MN, MT, NM, ND, OH, SD, TX) contributed 6 2% of the national emissions for 1976. 相似文献
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Rothwell JJ Evans MG Daniels SM Allott TE 《Environmental pollution (Barking, Essex : 1987)》2008,153(3):582-589
Upland peat soils are generally regarded as effective sinks of atmospherically deposited lead. However, the physical process of erosion has the potential to transform peat soils from sinks to sources of lead contamination. Lead input and fluvial lead outputs (dissolved+particulate) were estimated for a contaminated and severely eroding peatland catchment in the southern Pennines, UK. Lead input to the catchment is 30.0+/-6.0gha(-1)a(-1) and the output from the catchment is 317+/-22.4gha(-1)a(-1). Suspended particulate matter accounts for 85% of lead export. Contaminated peat soils of the catchment are a significant source of lead to the fluvial system. This study has demonstrated strong coupling between the physical process of erosion and the mobilization of lead into the fluvial system. The process of peat erosion should therefore be considered when estimating lead outputs from peatland catchments, especially in the context of climate change. 相似文献
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《Atmospheric environment (Oxford, England : 1994)》2007,41(18):3789-3796
A new device—the Portable In Situ Wind ERosion Lab (PI-SWERL)—for measuring the potential for wind erosion and dust emission from soil surfaces is described. The device uses an annular ring (inner diameter=39 cm, outer diameter=51 cm) that rotates 6 cm above the soil test surface. Dust and sand are mobilized by the shear created by the rotating ring. Dust concentrations within the chamber that encloses the annular ring are measured by light scattering, used as a surrogate for particulate matter mass concentrations. While the PI-SWERL does not realistically simulate natural wind erosion processes that are often driven by saltation, measurements with the device provide a robust index of wind erosion/dust emission potential. Compared to traditional field wind tunnels used for the same purpose, the PI-SWERL offers significant economy in size, portability, and ease of use. 相似文献
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Synthesis, characterization and application of a novel chemical sand-fixing agent-poly(aspartic acid) and its composites 总被引:1,自引:0,他引:1
A novel sand-fixing agent-poly(aspartic acid) and its composites were synthesized to improve sand particles compressive strength and anti-wind erosion properties. The relationship between the concentration of sand-fixing agent and the sand-fixing properties was studied by three kinds of aging tests. Some composites were choose to improve the sand-fixing property and the composition of 40% xanthan gum and 60% ethyl cellulose were chosen to compare sand-fixing property with lignosulfonate. The results showed that the sand-fixing and water-retaining properties of xanthan gum and ethyl cellulose composites were better than that of lignosulfonate. The biodegradability experiment showed that the PASP and its composites were environment-friendly products and the field test showed that the PASP composites could improve wind erosion disturbance. 相似文献
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Cueff Sixtine Alletto Lionel Dumény Valérie Benoit Pierre Pot Valérie 《Environmental science and pollution research international》2021,28(13):15934-15946
Environmental Science and Pollution Research - The main goals of conservation agriculture are to enhance soil fertility and reduce soil degradation, especially through erosion. However,... 相似文献
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Mine tailings are typical elements in post-mining landscapes which usually have high heavy metal contents and are affected by intensive erosion processes, above all in arid and semiarid areas. Revegetation of these sites is considered a low cost and suitable technology to effect surface stabilization. Spontaneous plant communities that colonize tailings in Southern Spain showed different behavior depending on the pH: in neutral tailings the plant communities were formed by less number of plant species than in acid tailings but they had less seasonal variations, showing a stable development. This spontaneous vegetation, that is adapted to metal toxicity and to drought, allows reducing air borne and water erosion, and may mitigate the spread of the contamination to the nearby areas. 相似文献
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The contribution of fluvial discharge and global fallout of 137Cs and mercury to sedimentation fluxes in Lake Shinji and Lake Nakaumi, Japan, was studied. The fluvial flux through soil erosion accounted for 11 to 27% of accumulated 137Cs in the sediments in the 1950's and 1960's, which were the periods of the most extensive atmospheric input, and for 90 to 100% in the 1990's. The vertical profiles of mercury concentrations in the lake sediments studied showed a maximum between 1959 and 1963, which was originated mostly from the extensive use of mercury-agrochemicals in paddyfields of the watershed in the past. These findings are representative examples of long-term contamination of lake sediments caused by the contaminated ground soil erosion. 相似文献
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Bouhlassa Saidati Bouhsane Naima 《Environmental science and pollution research international》2019,26(25):25452-25466
Environmental Science and Pollution Research - Soil erosion constitutes a serious threat for sustainable agriculture in many countries. Magnetic susceptibility of soil is a fast, cheap, and... 相似文献
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Huang Xuan Wang Kai-Rui Zou Yu-wen Cao Xin-Chun 《Environmental science and pollution research international》2021,28(10):12232-12244
Environmental Science and Pollution Research - At the watershed scale, soil erosion is a cascading system that includes detachment–transport–deposition processes while sediment yield is... 相似文献
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Piyal Aravinna Amarasooriya Pitawala Sudharma K. Yatigammana 《Journal of environmental science and health. Part. B》2017,52(1):37-47
Pesticides applied on agricultural lands reach groundwater by leaching, and move to offsite water bodies by direct runoff, erosion and spray drift. Therefore, an assessment of the mobility of pesticides in water resources is important to safeguard such resources. Mobility of pesticides on agricultural lands of Mahaweli river basin in Sri Lanka has not been reported to date. In this context, the mobility potential of 32 pesticides on surface water and groundwater was assessed by widely used pesticide risk indicators, such as Attenuation Factor (AF) index and the Pesticide Impact Rating Index (PIRI) with some modifications. Four surface water bodies having greater than 20% land use of the catchment under agriculture, and shallow groundwater table at 3.0 m depth were selected for the risk assessment. According to AF, carbofuran, quinclorac and thiamethoxam are three most leachable pesticides having AF values 1.44 × 10?2, 1.87 × 10?3 and 5.70 × 10?4, respectively. Using PIRI, offsite movement of pesticides by direct runoff was found to be greater than with the erosion of soil particles for the study area. Carbofuran and quinclorac are most mobile pesticides by direct runoff with runoff fractions of 0.01 and 0.08, respectively, at the studied area. Thiamethoxam and novaluron are the most mobile pesticides by erosion with erosion factions of 1.02 × 10?4 and 1.05 × 10?4, respectively. Expected pesticide residue levels in both surface and groundwater were predicted to remain below the USEPA health advisory levels, except for carbofuran, indicating that pesticide pollution is unlikely to exceed the available health guidelines in the Mahaweli river basin in Sri Lanka. 相似文献