167 research outputs found

    Déterminisme du ruissellement et de l'érosion hydrique de la parcelle au versant en milieu méditerranéen marneux

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    La lutte contre l’érosion hydrique passe par une meilleure comprĂ©hension et modĂ©lisation des mĂ©canismes en jeu depuis les zones « source » jusqu’aux zones de dĂ©pĂŽt des sĂ©diments. Ce papier prĂ©sente et analyse 4 annĂ©es de mesures du ruissellement et de l’érosion au niveau de trois stations de mesures construites sur le bassin versant de Kamech (Cap Bon, Tunisie) Ă  l’exutoire d’une parcelle agricole (1.32 ha), d’une ravine (1.37 ha) et du micro-bassin (15.2 ha) englobant la parcelle et la ravine. L’objectif de ce papier est de tester les facteurs dĂ©terminants du ruissellement et de l’érosion sur chaque site et de comparer le fonctionnement hydro-Ă©rosif entre les trois stations. Les rĂ©sultats montrent un comportement hydrologique et Ă©rosif trĂšs similaire aux trois Ă©chelles. Le ruissellement apparaĂźt principalement guidĂ© par la dynamique de fermeture des trĂšs nombreuses fentes de retrait qui apparaissent chaque Ă©tĂ© sur le bassin. De bonnes corrĂ©lations linĂ©aires entre pluie et lame ruisselĂ©e ont pu ĂȘtre Ă©tablies sur les trois stations en diffĂ©renciant les pĂ©riodes avant et aprĂšs le cumul de pluie de 250 mm. Les masses Ă©rodĂ©es prĂ©sentent de bonnes corrĂ©lations avec les dĂ©bits maximaux (RÂČ entre 0.64 et 0.97) et avec les masses Ă©rodĂ©es aux autres stations (RÂČ de 0.88 Ă  0.96). GrĂące Ă  ces relations, les masses Ă©rodĂ©es ont pu ĂȘtre reconstituĂ©es pour les Ă©vĂ©nements ruisselants sans donnĂ©es d’érosion mesurĂ©es, ces Ă©vĂ©nements contribuant Ă  moins de 20% des bilans Ă©rosifs. Sur les 4 annĂ©es de mesure, les taux d’érosion atteignent 29.2 t/ha/an pour la parcelle, 38.4 t/ha/an pour la ravine et 22.1 t/ha/an pour le microbassin. Les diffĂ©rences de taux d’érosion s’expliquent principalement par i) la contribution des flancs de la ravine mesurĂ©es par des suivis topographiques, ii) la prĂ©sence au sein du microbassin de zones de parcours (3.6 ha) peu productrices de sĂ©diments

    Soil surface structure stabilization by municipal waste compost application

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    ABSTRACT tional farmyard manure which is no longer available in intensive cropping areas. Loess-derived soils of the northern Paris basin are prone to surface Beneficial effects of sewage sludge application have structure degradation leading to erosion, flooding, and pollution. and soil material were seldom suggested, but a close from the top of surface aggregates to illuviate a few millimeters deeper

    Rural Development Programme measures on cultivated land in Europe to mitigate greenhouse gas emissions – regional ‘hotspots’ and priority measures

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    © 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.Agriculture is a significant source of GHG emissions, contributing 10% of total emissions within the EU-28. Emissions from European agriculture have been reduced, albeit at the expense of crop yield and the risk of production displacement (the transfer of production, and associated emissions, to land outside of Europe). This article assesses the impact on GHG emissions of selected European Rural Development Program measures, representative of a diversity of management strategies implemented on cultivated land, within nine European Member States. Climatic zone and underlying spatial environmental variables were accounted for using a novel technique, “Regional Variation Categories,” developed with European-scale GIS data sets. Production displacement is assessed with two benchmarks: (1) compared with existing crop production and (2) relative to a “minimum requirement” land management scenario, where an emissions reduction of less than this does not constitute mitigation. Most measures reduce emissions relative to the baseline crop scenario; however, many do not reduce emissions beyond the “minimum requirement,” this being limited to measures such as catch crops and within-field grass areas to prevent soil erosion. The selection and targeting of measures to maximize agricultural GHG mitigation on cultivated land within Europe is discussed...Peer reviewedFinal Published versio

    Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin

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    Rainfall is the key factor to understand soil erosion processes, mechanisms, and rates. Most research was conducted to determine rainfall characteristics and their relationship with soil erosion (erosivity) but there is little information about how atmospheric patterns control soil losses, and this is important to enable sustainable environmental planning and risk prevention. We investigated the temporal and spatial variability of the relationships of rainfall, runoff, and sediment yield with atmospheric patterns (weather types, WTs) in the western Mediterranean basin. For this purpose, we analyzed a large database of rainfall events collected between 1985 and 2015 in 46 experimental plots and catchments with the aim to: (i) evaluate seasonal differences in the contribution of rainfall, runoff, and sediment yield produced by the WTs; and (ii) to analyze the seasonal efficiency of the different WTs (relation frequency and magnitude) related to rainfall, runoff, and sediment yield. The results indicate two different temporal patterns: the first weather type exhibits (during the cold period: autumn and winter) westerly flows that produce the highest rainfall, runoff, and sediment yield values throughout the territory; the second weather type exhibits easterly flows that predominate during the warm period (spring and summer) and it is located on the Mediterranean coast of the Iberian Peninsula. However, the cyclonic situations present high frequency throughout the whole year with a large influence extended around the western Mediterranean basin. Contrary, the anticyclonic situations, despite of its high frequency, do not contribute significantly to the total rainfall, runoff, and sediment (showing the lowest efficiency) because of atmospheric stability that currently characterize this atmospheric pattern. Our approach helps to better understand the relationship of WTs on the seasonal and spatial variability of rainfall, runoff and sediment yield with a regional scale based on the large dataset and number of soil erosion experimental stations.Spanish Government (Ministry of Economy and Competitiveness, MINECO) and FEDER Projects: CGL2014 52135-C3-3-R, ESP2017-89463-C3-3-R, CGL2014-59946-R, CGL2015-65569-R, CGL2015-64284-C2-2-R, CGL2015-64284-C2-1-R, CGL2016-78075-P, GL2008-02879/BTE, LEDDRA 243857, RECARE-FP7, CGL2017-83866-C3-1-R, and PCIN-2017-061/AEI. Dhais Peña-Angulo received a “Juan de la Cierva” postdoctoral contract (FJCI-2017-33652 Spanish Ministry of Economy and Competitiveness, MEC). Ana Lucia acknowledge the "Brigitte-Schlieben-Lange-Programm". The “Geoenvironmental Processes and Global Change” (E02_17R) was financed by the AragĂłn Government and the European Social Fund. JosĂ© AndrĂ©s LĂłpez-TarazĂłn acknowledges the Secretariat for Universities and Research of the Department of the Economy and Knowledge of the Autonomous Government of Catalonia for supporting the Consolidated Research Group 2014 SGR 645 (RIUS- Fluvial Dynamics Research Group). Artemi CerdĂ  thank the funding of the OCDE TAD/CRP JA00088807. JosĂ© MartĂ­nez-Fernandez acknowledges the project Unidad de Excelencia CLU-2018-04 co-funded by FEDER and Castilla y LeĂłn Government. Ane Zabaleta is supported by the Hydro-Environmental Processes consolidated research group (IT1029-16, Basque Government). This paper has the benefit of the Lab and Field Data Pool created within the framework of the COST action CONNECTEUR (ES1306)

    Relationship of weather types on the seasonal and spatial variability of rainfall, runoff, and sediment yield in the western Mediterranean basin

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