Search results for "soil erosion"
showing 10 items of 149 documents
Effectiveness of carbon isotopic signature for estimating soil erosion and deposition rates in Sicilian vineyards
2015
Abstract Traditional methods for measurement of soil erosion provide information on erosion rates and mechanisms but fail to determine the spatial distribution of sediment redistribution. Recent studies have used carbon (C) stable isotopes to trace sediment and to monitor soil organic carbon (SOC) redistribution. The difference in δ 13 C values in a slope-transect or in a watershed provides information about the source of suspended organic matter and sediment removal and deposition, but miss enough information to quantify sediment loss. The objective of this research was to develop a method to estimate soil erosion using the natural discrimination of δ 13 C-SOC with soil depth, comparing δ …
Soil Erosion as an Environmental Concern ... for Everyone?
2020
Nowadays, the scientific community is aware of the negative environmental impacts of soil erosion on ecosystem services. Soil erosion is one of the most important causes of land degradation because of its immediate influence of the most fertile topsoil parts. It is well-known that questions related to who, what, why, where and when soil erosion causes negative impacts must be considered by stakeholders and policymakers. However, why do the Sustainable Development Goals tell anything about soil erosion? In this keynote, we will try to show the importance to develop tools which can be used to assess soil erosion to obtain convincing results for stakeholders and policymakers. According to this…
Soil erosion assessment on tillage and alternative soil managements in a Sicilian vineyard
2011
Mediterranean crops favour high erosion rates. Vineyards use to reach the highest soil and water losses due to the lack of vegetation cover. A topographical approach by means of the use of vineyards poles as fixed reference point as erosion markers allowed to quantify high and non-sustainable soil erosion rates on the Sicilian vineyards during 9 years. In order to develop strategies to control the soil losses, seven land management were selected and applied in a typical blanc wine grape vineyard located in southwestern Sicily. Comparable plots were managed traditionally using conventional tillage and alternatively using various cover crops: 1) Vicia faba; 2) Vicia faba and Vicia sativa; 3) …
A comprehensive analysis of Universal Soil Loss Equation-based models at the Sparacia experimental area
2020
Improving Universal Soil Loss Equation (USLE)‐based models has large interest because simple and reliable analytical tools are necessary in the perspective of a sustainable land management. At first, in this paper, a general definition of the event rainfall‐ runoff erosivity factor for the USLE‐based models, REFₑ = (QR)ᵇ¹(EI₃₀)ᵇ², in which QR is the event runoff coefficient, EI₃₀ is the single‐storm erosion index, and b₁ and b₂ are coefficients, was introduced. The rainfall‐runoff erosivity factors of the USLE (b₁ = 0 and b₂ = 1), USLE‐M (b₁ = b₂ = 1), USLE‐MB (b₁ ≠ 1 and b₂ = 1), USLE‐MR (b₁ = 1 and b₂ ≠ 1), USLE‐MM (b₁ = b₂ ≠ 1), and USLE‐M2 (b₁ ≠ b₂ ≠ 1) can be defined using REFₑ. Then t…
Using very high resolution (VHR) imagery within a GEOBIA framework for gully mapping: an application to the Calhoun Critical Zone Observatory
2019
AbstractGully erosion is a form of accelerated erosion that may affect soil productivity, restrict land use, and lead to an increase of risk to infrastructure. An accurate mapping of these landforms can be difficult because of the presence of dense canopy and/or the wide spatial extent of some gullies. Even where possible, mapping of gullies through conventional field surveying can be an intensive and expensive activity. The recent widespread availability of very high resolution (VHR) imagery has led to a remarkable growth in the availability of terrain information, thus providing a basis for the development of new methodologies for analyzing Earth's surfaces. This work aims to develop a ge…
Effectiveness of cover crops to reduce loss of soil organic matter in a rainfed vineyard
2020
Cover crops (CCs) minimize the loss of soil in permanent cropping systems where the soil is usually bare due to intense tillage or overuse of herbicides. The topsoil, the richer layer in soil organic carbon and organic matter (OM), is affected by water erosion. Nature-based solutions appear as a suitable option for sustainable farming. In this study, the effectiveness of two years of CC management to reduce the OM loss is evaluated in a rainfed vineyard in a rolling landscape (Huesca, NE Spain). Two sediment traps collected runoff over 15 months. Topsoil OM contents (1.64% and 1.60%) and sediment/soil OM enrichment ratio (2.61 and 3.07) were similar. However, the average annual rate of OM l…
Practical thresholds to distinguish erosive and rill rainfall events
2019
Abstract In this paper, 1017 rainfall events from 2008 to 2017 are used to identify the rainfall threshold that produces upland erosion at the Masse (central Italy) and Sparacia (southern Italy) experimental stations. The rainfall events are classified into three classes: non-erosive, interrill-only and rill. The threshold values for separating as correctly as possible the erosive rains (case I) and the rill rains (case II) are derived solely from the hyetograph. Each threshold value is obtained by imposing that the long-term erosivity of the events above the threshold is equal to the long-term erosivity of all erosive events (case I) or only rill events (case II). The performances of selec…
Relationships between societies and their environment in the Sahel in southwestern Niger over the past four thousand years : a geoarchaeological appr…
2013
The Sahel, a zone between the Sahara Desert and the Sudan forests, is currently experiencing major environmental changes. Since the droughts in 1970s and 1980s, and with the high population growth rate, vegetation cover has deteriorated considerably, contributing to increased runoff and soil erosion. Starting from this observation, we undertook the study of past societies in the Niamey region, to assess their impact on the environment. The lack of archaeological data meant that it was necessary to identify key indicators of occupation during the Neolithic and the Iron Age. In addition to providing new evidence to date the Neolithic site of Kirkissoy, a sedimentary study was conducted on a p…
Linking clay enrichment and sediment delivery processes
2002
Recent research has directed attention to the size distribution of eroded material because of its influence on deposition mechanics and in carrying capacity of pollutant materials. At first, in this paper the relationship between aggregate breakdown mechanism and erosion processes is briefly reviewed. Then the link between the clay enrichment ratio and the sediment delivery ratio at morphological unit scale is investigated. For 129 soil samples well distributed over the Sicilian Sparacia basin, the values for the experimental clay enrichment ratio calculated by the measured ultimate grain-size distributions are compared with the theoretical clay enrichment ratio values obtained by a procedu…
Assessment of climate impacts on hydrology and geomorphology of semiarid headwater basins using a physically-based model.
2013
The response of watershed erosion rates to changes in climate is expected to be highly non-linear and thus demands for mechanistic approaches to improve our understanding of the underlying causes. In this study, the integrated geomorphic component tRIBS-Erosion of the physically-based, spatially distributed hydrological model, tRIBS, the TIN-based Real-time Integrated Basin Simulator, is used to analyze the sensitivity of small semi-arid headwater basins to projected climate conditions. Observed historic climate and downscaled realizations of general circulation models from CMIP3 inform the stochastic weather generator AWE-GEN (Advanced WEather GENerator), which is used to produce two clima…