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THE EVALUATION OF SOIL EROSION OFF-SITES EFFECTS IN LARGE BASINS: THE STUDYCASE OF LERMA-CHAPALA WATERSHED, MEXICO
Helena Cotler A.,Susana Gutierrez D.,Carlos Enriquez G.,Arturo Garrido P.
Revista Sociedade & Natureza , 2005,
Abstract: One of the primary global concerns during the new millennium is the assessment of the impact of accelerated soil erosion on the economy and the environment (Pimentel et al. 1995; Lal, 1995). Erosion damages the site on which it occurs and also has undesirable effects off-site in the larger environment. Erosion moves sediments and nutrients out of the land, creating the two most widespread water pollution problems in the rivers, lakes and dams. The nutrients impact water quality largely through the process of eutrophication caused by an excessive content of nitrogen and phosphorus. In addition to the nutrients presence, sediment and runoff may also carry toxic metals and organic compounds, such as pesticides (Brady and Weil, 1999; Lal, 1994; de Graaf, 2000; Renschler and Harbor, 2002). The sediment itself is a major pollutant causative agent, causing a wide range of environmental damages. The sedimentation of dams and canals, reduces their lifetime and efficiency, promoting a high restoration cost to the downstream users and affecting thenational budget. In this sense, sedimentation knowledge is an important tool to guide spatial planning efficiently. Despite more than six decades of research, sedimentation is still probably the most serious technical problem faced by the dam industry (Mc Cully, 2001). Many studies estimate present-day fluvial sediment and solute loads including both natural and accelerated soil erosion (Douglas, 1990). However, as Douglas mentioned (op.cit) many do not include all the erosion caused by human activity, because the eroded sediment is redeposited after a short movement downslope. Many soil particles are detached and carried downslope only to be held and trapped by a plant, tree or other obstacle a little further downslope. The sediment reaching the valley floor may not be completely removed by the river, but may be redistributed as alluvial floodplain deposits. The sediment transported downstream may be redeposited again on another part of the floodplain or in managed rivers in reservoirs.
Combined use of stable isotopes and fallout radionuclides as soil erosion indicators in a forested mountain site, South Korea  [PDF]
K. Meusburger,L. Mabit,J.-H. Park,T. Sandor
Biogeosciences Discussions , 2013, DOI: 10.5194/bgd-10-2565-2013
Abstract: The aim of this study is to assess and to validate the suitability of the stable nitrogen and carbon isotope signature as soil erosion indicators in a mountain forest site in South Korea. Our approach is based on the comparison of the isotope signature of "stable" landscape positions (reference sites), which are neither affected by erosion nor deposition, with eroding sites. For undisturbed soils we expect that the enrichment of δ15N and δ13C with soil depth, due to fractionation during decomposition, goes in parallel with a decrease in nitrogen and carbon content. Soil erosion processes potentially weaken this correlation. 137Cs-method and the Revised Universal Soil Loss Equation are applied for the soil erosion quantification. The erosion rates obtained with the 137Cs method range from 0.9 t ha 1 yr 1 to 7 t ha 1 yr 1. Considering the steep slopes of up to 40° and the erosive monsoon events (R-factor of 6600 MJ mm ha 1 h 1 yr 1), the rates are plausible and within the magnitude of the RUSLE- modelled soil erosion rates, varying from 0.02 t ha 1 yr 1 to 5.1 t ha 1 yr 1. The soil profiles of the reference sites showed significant (p < 0.0001) correlations between nitrogen and carbon content and its corresponding δ15N and δ13C signatures. In contrast, for the eroding sites this relationship was weaker and for the carbon not significant. These results verify the usefulness of the stable carbon isotope signature as qualitative indicator for soil disturbance. We could show further that the δ15N isotope signature can be used similarly for uncultivated sites. We thus propose that the stable δ15N and δ13C signature of soil profiles could serve as a tool confirming the accurate choice of the reference site in soil erosion studies using the 137Cs-method.
Insights into preventive measures for dental erosion
Magalh?es, Ana Carolina;Wiegand, Annette;Rios, Daniela;Honório, Heitor Marques;Buzalaf, Marília Afonso Rabelo;
Journal of Applied Oral Science , 2009, DOI: 10.1590/S1678-77572009000200002
Abstract: dental erosion is defined as the loss of tooth substance by acid exposure not involving bacteria. the etiology of erosion is related to different behavioral, biological and chemical factors. based on an overview of the current literature, this paper presents a summary of the preventive strategies relevant for patients suffering from dental erosion. behavioral factors, such as special drinking habits, unhealthy lifestyle factors or occupational acid exposure, might modify the extent of dental erosion. thus, preventive strategies have to include measures to reduce the frequency and duration of acid exposure as well as adequate oral hygiene measures, as it is known that eroded surfaces are more susceptible to abrasion. biological factors, such as saliva or acquired pellicle, act protectively against erosive demineralization. therefore, the production of saliva should be enhanced, especially in patients with hyposalivation or xerostomia. with regard to chemical factors, the modification of acidic solutions with ions, especially calcium, was shown to reduce the demineralization, but the efficacy depends on the other chemical factors, such as the type of acid. to enhance the remineralization of eroded surfaces and to prevent further progression of dental wear, high-concentrated fluoride applications are recommended. currently, little information is available about the efficacy of other preventive strategies, such as calcium and laser application, as well as the use of matrix metalloproteinase inhibitors. further studies considering these factors are required. in conclusion, preventive strategies for patients suffering from erosion are mainly obtained from in vitro and in situ studies and include dietary counseling, stimulation of salivary flow, optimization of fluoride regimens, modification of erosive beverages and adequate oral hygiene measures.
A policy and technical measures for controlling soil and water loss in the Loess Plateau of China
Wu Qinxiao,Li Yinchu,
Wu Qinxiao
,Li Yinchu

环境科学学报(英文版) , 1990,
Abstract: Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for erosion in this area, and puts forward a comprehensive controlling policy on the basis of the principles of ecology and practise of Chinese scientists for 40 years. In conformity with the policy, a number of technical measures for controlling soil and water loss are suggested.
Erosion control blankets, organic amendments and site variability influenced the initial plant community at a limestone quarry in the Canadian Rocky Mountains  [PDF]
A. C. Cohen-Fernández,M. A. Naeth
Biogeosciences Discussions , 2013, DOI: 10.5194/bgd-10-3009-2013
Abstract: Season of seeding and soil amendment with manure mix, wood shavings and erosion control blankets were evaluated over two growing seasons to determine their effect on soil properties and native grass establishment at a Canadian limestone quarry and lime processing plant. Season (fall, spring) of soil amending and seeding did not significantly affect revegetation or soil properties. Site characteristics such as slope, aspect, initial soil nutrients and surrounding plant communities influenced early plant community development and overall effects of soil treatments. Erosion control blankets resulted in the highest seeded plant cover and the lowest non seeded plant cover despite not significantly changing soil chemical properties. Total nitrogen and carbon significantly increased establishment of seeded grasses and non seeded species. Increased nitrogen and carbon in the constructed soils were best achieved through addition of manure. Wood shavings did not favour establishment of vegetation and resulted in similar, and in some cases less, vegetation than controls. Assisted revegetation increased plant cover from < 6 to 50% and reduced cover of non seeded species. Amendments that modified both chemical and physical soil conditions were best to increase vegetation establishment in the harsh conditions of the quarry.
The costs of soil erosion
Telles, Tiago Santos;Guimar?es, Maria de Fátima;Dechen, Sonia Carmela Falci;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000200001
Abstract: the aim of this study was a survey of the estimated costs of soil erosion, an issue of fundamental importance in view of the current worldwide discussions on sustainability. a list was drawn up of research papers on erosion (on-site and off-site effects) and their respective costs. the estimates indicate the amount of resources spent in the process of soil degradation, raising a general awareness of the need for soil conservation. on-site costs affect the production units directly, while off-site costs create a burden borne by the environment, economy and society. in addition, estimating the costs of soil erosion should be effective to alert the agricultural producers, society and government for the need for measures that can be implemented to bring erosion under control. among the various estimates of soil erosion costs between 1933 a 2010, the highest figure was 45.5 billion dollars a year for the european union. in the united states, the highest figure was 44 billion dollars a year. in brazil, estimates for the state of paraná indicate a value of 242 million dollars a year, and for the state of s?o paulo, 212 million dollars a year. these figures show, above all, that conservation measures must be implemented if crop and livestock farming production are to be sustainable.
On-Site Effects and Cost of Fertility Erosion from Five Small Reservoir Catchments in the Upper East Region of Ghana
BK Amegashie, C Quansah, AW Agyare, M Bonsu, SN Odai
Journal of Science and Technology (Ghana) , 2012,
Abstract: A study was carried out in the Upper East Region of Ghana to assess the on-site effects and the cost of fertility erosion from five small reservoir catchments (Dua, Doba, Zebilla, Kumpalgogo and Bugri). The catchment soils and reservoir sediments were sampled and analyzed for their bulk density and nutrient content. The mean reduction in soil depth in the various catchments was 3.996±3.806 mm y-1 in the order of Kumpalgogo>Dua>Bugri>Zebilla>Doba. The corresponding decrease in the water holding capacity of the top 20 cm depth of the catchment soils ranged from 0.563 to 4.698 % per year. The percentage loss in the total nutrient stocks in the top 20 cm of the catchments as eroded sediment-bound nutrients ranged from 9.63 to 64.71, 7.87 to 56.83, 6.12 to 54.82, 1.26 to 40.14, 49.86 to 12.65, 16.84 to 72.07 for OC, N, P, K, Ca and Mg, respectively. The total amount of nutrient loss in kg ha-1 among the reservoirs ranged from 2383 to 19672 for OC, 153 to 3048 for N, 3.15 to 42.59 for P, 41 to 290 for K, 432 to 2158 for Ca, and 63 to 483 for Mg. The cost of N, P and K removed by erosion was calculated by the Replacement Cost Method. The total cost per year (GH¢ ha-1 y-1) of fertilizers (sulphate of ammonia, single superphosphate and muriate of potash) was 286.15 for Dua, 74.289 for Doba, 225.061 for Zebilla, 1119.997 for Kumpalgogo and 96.376 for Bugri. The study has amply shown that soil loss through erosion reduces top soil depth, nutrient stocks and the water holding capacity of catchment soils. This will adversely affect crop productivity if no control measures are implemented. This can also lead to land degradation.
A Review of Distr ibuted Model for Soil Erosion and Sediment Yield
分布式侵蚀产沙模型研究进展

CAI Qiangguo,YUAN Zaijian,CHENG Qinjuan,QIN Jie,
蔡强国
,袁再健,程琴娟,秦杰

地理科学进展 , 2006,
Abstract: With the development of computer and GIS,distributed model for soil erosion and sediment yield has become the developing direction in the field of soil erosion.This paper discussed the technical route and realization of distributed model based on the analysis of the main distributed models home and abroad at present.Finally,the paper indicated some problems of the distributed models for soil erosion and sediment yield in our country:(1) there are many problems in the developing of distributed models for soil erosion and sediment yield which are based on the distributed hydrological models,although the latter provides many references for study of the former;(2) the distributed models for soil erosion and sediment yield are mainly based on the loess plateau and the models are regional at present in our county;(3) most relational expressions of soil erosion and sediment are mainly empirical and the process of soil influx is simply beginning to be considered nowadays;(4) the spatial and temporal change of single rain event was ignored in most distributed models for soil erosion and sediment yield at present.In the future,the above problems should be solved in the constructing of distributed model for soil erosion and sediment yield in our country.
THE USE OF BIOTEXTILES TO RECUPERATE DEGRADADED AREAS BY EROSION
Marcia Silva Furtado,Neilianne de Fátima Costa Lima,Ulisses Denache Vieira Souza,Jane Karina Silva Mendon?a
Revista Sociedade & Natureza , 2005,
Abstract: The erosion is a process that results from the conjunct action of many natural agents over the grounds. However, this process can be accelerated, mainly by the action of the human being that has caused numerous degrading actions of the environment, depending on the level of intensity and from the characteristic of his intervention. Among the ways of degradation it is possible to stand out accelerated erosive processes, like ravines and gullies.These processes can be mitigated with the use of several technical and material alternatives, being necessary specific knowledge for the right choice, in each case.In S o Luís, a research project started since 2002 and thanks this project, it was indentified and monitorated several erosive processes with high degree of evolution, like gullies in Salina, Sacavém, Ara agi, Castel o, Bequim o, Coeduc, Santa Eulália site, among others.After these phases of the recognition and monitoration, the efforts for recuperation of the degraded areas have been developed with the use of bioengineering techniques. Such initiatives have been applied in different situations, with positive results for being an alternative which makes use of biodegradable materials such as vegetal fibers, wooden stakes, rigid iron-like structures, besides vegetation to make the soil more stable, lowering the costs and providing improvement to the environmental balance. Firstly, biodegradable screens, made of buriti, carnaúba, tucum, baba u and marajá palm will be installed, as a matter of an experiment, at Sacavém’s gully, in S o Luís – Maranh o State.The choice of the gullies in Sacavém occured because the necessity of the area, once this area offers serious risks to the population around, but later the project is going to contemplate the other monitored areas.
RELATIONSHTP OF ECO-ENVIRONMENTAL CHANGE AND NATURAL EROSION AND MAN-MADE ACCELERATED EROSION
自然侵蚀和人为加速侵蚀与生态环境演

Zheng Fenli,
郑粉莉

生态学报 , 1995,
Abstract: he natural landscape of loess plateau have been changed by severe soil erosion. The Zi-wuling forest region provides a good study area for tracing back eco-environmental change and natural erosion and man-made accelerated erosion. Using the methods of typical region investigation, experimental study in site,and chemical analysis of samples,impact of forest vegetation destruction and restoration on soil erosion change,characteristics of natural ero-sion under the condition of natural ecological balance,man-made accelerated erosion caused by forest vegetation destruction,and the processes of man-made accelerated erosion and soil degradation have been analysed and discussed
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