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Rockwall retreat on badlands in Slovene Istria
Matija Zorn,Matja? Miko?
Geologija , 2008,
Abstract: Steep bare rocky slopes that are badlands at the same time, are a morphogenetic particularity of the flyschpart of the Istrian Peninsula. On them, microrelief forms are of a short life cycle, since erosion processes are fast. On the basis of measurements of sediment production in flysch rocks on fourerosion plots in the Rokava watershed situated south of the village of Marezige, we show in this paper how fast these processes are. The annual sedimentproduction in flysch rocks is on average around 80kg/m2, which means that the slope retreat rate is about 35 mm/year.Further more, weekly measurements of sediment production in flysch rockf or the period of 15 months(from February 2005 till April 2006) are shown, as well as weekly and seasonal averages. Linear statistical correlations between sediment production in flysch rocks and weather conditions are also presented.
The Impact of Technical and Biological Measures on Soil and Erosion Dynamics in the Research Site of Abrami
Nikola Pernar,Danko Holjevi?,Darko Bak?i?,Josip Petra?
Croatian Journal of Forest Engineering , 2011,
Abstract: Soil erosion is one of the most devastating soil degradation processes. In temperate climate regions, soil erosion rarely assumes excessive proportions. In the management of forest soil, the potential erosion threat drastically increases with an increase in climate aridity. Water erosion is particularly favored by parent materials of low water permeability and by soils derived from such materials. In theMediterranean and sub-Mediterranean area of Croatia, these are primarily flysch, marl and Werfen schists. These materials show good physical weathering properties, thus providing a rich source of erosion material.As a rule, the soil formed from such parentmaterial is of silty-clayey to clayey texture, and has a relatively low infiltration capacity. The soil unprotected by vegetation (burned sites) manifests particularly devastating forms of water-induced erosion. In the past 50 years, flysch terrains of Istria have been subjected to a series of technical, biological and biological- technical treatments aimed at preventing water erosion and recovering the eroded soils. An experimental (research) site was set up in Abrami near Buzet for the purpose of monitoring erosion processes and rehabilitation effects of different biological-technical and biological methods of eroded area recovery. The effects of the treatments on soil properties in the research site are in the form of progressive pedogenetic processes. Asynergy of the effects of recovery methods and different natural conditions (relief, vegetation) in the experimental site is particularly well reflected in erosion indicators, such as the production of erosion sediment (erosion production), and to a lesser extent, the surface flow index. For this reason, research in this work focuses primarily on soil properties and erosion production dynamics. From the geological-lithological aspect, the research site of Abrami is made up of Eocene flysch composed of alternate layers of light grey marl and dark lime sandstone, i.e. thinner or thicker interbeds of sandy limestone. The climate is sub-Mediterranean. The mean annual temperature is 12 °C and the mean annual precipitation is 975 mm. The natural potential vegetation in the localities is represented by the community of hop hornbeam and autumn moor grass. Established in 1956 on the slope exposed to highly pronounced erosion processes, the research site has an area of 23.46 ha.Aseries of technical and biological erosion recovery measures had been undertaken in the site by 1963 for the purpose of investigating their applicability in practice. Technical activitie
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.
Modeling the fluid/soil interface erosion in the Hole Erosion Test
Kissi B.,Parron Vera M. Angel,Rubio Cintas M. D.,Khamlichi A.
MATEC Web of Conferences , 2012, DOI: 10.1051/matecconf/20120100003
Abstract: Soil erosion is a complex phenomenon which yields at its final stage to insidious fluid leakages under the hydraulic infrastructures known as piping and which are the main cause of their rupture. The Hole Erosion Test is commonly used to quantify the rate of piping erosion. In this work, The Hole Erosion Test is modelled by using Fluent software package. The aim is to predict the erosion rate of soil during the hole erosion test. The renormalization group theory – based k–ε turbulence model equations are used. This modelling makes it possible describing the effect of the clay concentration in flowing water on erosion. Unlike the usual one dimensional models, the proposed modelling shows that erosion is not uniform erosion along the hole length. In particular, the concentration of clay is found to increase noticeably the erosion rate.
Soil Erosion Threatens Food Production  [PDF]
David Pimentel,Michael Burgess
Agriculture , 2013, DOI: 10.3390/agriculture3030443
Abstract: Since humans worldwide obtain more than 99.7% of their food (calories) from the land and less than 0.3% from the oceans and aquatic ecosystems, preserving cropland and maintaining soil fertility should be of the highest importance to human welfare. Soil erosion is one of the most serious threats facing world food production. Each year about 10 million ha of cropland are lost due to soil erosion, thus reducing the cropland available for world food production. The loss of cropland is a serious problem because the World Health Organization and the Food and Agricultural Organization report that two-thirds of the world population is malnourished. Overall, soil is being lost from agricultural areas 10 to 40 times faster than the rate of soil formation imperiling humanity’s food security.
Research progress on the effects of soil erosion on vegetation

Juying Jiao,Houyuan Zou,Yanfeng Ji,Ning Wang,

生态学报 , 2009,
Abstract: The relationship between vegetation and soil erosion deserves attention due to its scientific importance and practical applications. A great deal of information is available about the mechanisms and benefits of vegetation in the control of soil erosion, but the effects of soil erosion on vegetation development and succession is poorly documented. Research shows that soil erosion is the most important driving force for the degradation of upland and mountain ecosystems. Soil erosion interferes with the process of plant community development and vegetation succession, commencing with seed formation and impacting throughout the whole growth phase and affecting seed availability, dispersal, germination and establishment, plant community structure and spatial distribution. There have been almost no studies on the effects of soil erosion on seed development and availability, of surface flows on seed movement and redistribution, and their influences on soil seed bank and on vegetation establishment and distribution. However, these effects may be the main cause of low vegetation cover in regions of high soil erosion activity and these issues need to be investigated. Moreover, soil erosion is not only a negative influence on vegetation succession and restoration, but also a driving force of plant adaptation and evolution. Consequently, we need to study the effects of soil erosion on ecological processes and on development and regulation of vegetation succession from the points of view of pedology and vegetation, plant and seed ecology, and to establish an integrated theory and technology for deriving practical solutions to soil erosion problems.
Soil Erosion by Water in Perennial Plantations of the Ilok Region
Antonija Kustura,Ivica Kisi?,Ferdo Ba?i?,Aleksandra Juri?i?
Agriculturae Conspectus Scientificus (ACS) , 2008,
Abstract: Soil erosion by water is a natural process, in which soil particles get detached from soil mass, transported and deposited at a distance. Erosion depends on a number of natural factors, such as terrain slope, amount and intensity of precipitation, soil (structure, mechanical composition, permeability, infiltration, etc.), wind, crop rotation, and plant cover. Soil erosion by water is one of the most dangerous soil damaging processes. In the hilly part of the studied region, erosion causes great problems to fruit and wine production. The principal goal of this work is to find ways of reducing erosion by applying appropriate agricultural management practices, different methods of plant residue management, and radical conservation practices. Research results indicate that erosion cannot be prevented (especially in case of extreme weather conditions – very intensive precipitation), but it may be reduced to a tolerable level by selecting optimal agricultural practices.
Soil Erosion in Britain: Updating the Record  [PDF]
John Boardman
Agriculture , 2013, DOI: 10.3390/agriculture3030418
Abstract: Concern about soil erosion on arable land in Britain dates back at least 40 years. Monitoring schemes and case studies have subsequently identified the areas at risk, the rates and frequencies and the major factors responsible for erosion. Initial concern focused on impacts on the farm and therefore on food production. Latterly the emphasis has shifted to off-farm impacts particularly reservoir sedimentation, muddy flooding of properties and the ecological damage to watercourses due to nutrient enrichment, pesticides and damage to fish spawning grounds from fine-sediment inputs. The shift has therefore been to concerns about a healthy and sustainable environment which includes soils. Government agencies, the water companies and the farming industry have lagged behind scientific studies in recognising and addressing erosion problems. Attempts at mitigation are now largely driven by the need to comply with the EU Water Framework Directive whereby watercourses must reach “good status” by 2015. Future changes in land use and climate will offer further challenges in terms of effective monitoring and compliance.
Soil erosion and management on the Loess Plateau

CAI Qiang-guo,

地理学报 , 2001,
Abstract: The Loess Plateau is well known to the world for its intense soil erosion. The root cause for river sedimentation of Yellow River (Huanghe) and its resultant "hanging river" in certain section is soil and water loss on the Loess Plateau. The Loess Plateau has a long cultivation history, hence population growth, vegetation degeneration and plugging constitute the chief reason for serious soil and water loss on Loess Plateau. This paper analyses several successful cases and failures in soil conservation, presents practical soil conservation technique and related benefit analysis, and discusses some effective methods adopted in China in soil erosion control, research directions and future perspectives on Loess Plateau.
Process identification of soil erosion in steep mountain regions
N. Konz, D. Baenninger, M. Konz, M. Nearing,C. Alewell
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2010,
Abstract: Mountainous soil erosion processes were investigated in the Urseren Valley (Central Switzerland) by means of measurements and simulations. The quantification of soil erosion was performed on hill slope scale (2·20 m) for three different land use types: hayfields, pastures with dwarf shrubs and pastures without dwarf shrubs with three replicates each. Erosion rates during growing season were measured with sediment traps between June 2006 and November 2007. Long-term soil erosion rates were estimated based on Cs- 137 redistribution. In addition, soil moisture and surface flow were recorded during the growing season in the field and compared to model output. We chose the WEPP model (Water Erosion Prediction Project) to simulate soil erosion during the growing season. Model parameters were determined in the field (slope, plant species, fractional vegetation cover, initial saturation level), by laboratory analyses (grain size, organic matter) and by literature study. The WEPP model simulates sheet erosion processes (interrill and splash erosion processes, please note that no rill erosion occurs at our sites). Model output resulted in considerable smaller values than the measured erosion rates with sediment traps for the same period. We attribute the differences to observed random gravity driven erosion of soil conglomerates. The Cs-137 measurements deliver substantially higher mean annual erosion rates, which are most likely connected to snow cover related processes such as snow gliding and avalanche activities.
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