Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Titre : Wind born(e) landscapes : the role of wind erosion in agricultural land management and nature development

Auteur : Riksen, M.J.P.M. 

Université de soutenance : Wageningen Universiteit

Grade : PhD thesis 2006

Résumé partiel
Wind has played an important role in the geological development of the north-western Europe. Various aeolian deposits such as inland dunes, river dunes, cover sands, drift sands and coastal dunes, form the base of large areas in our present landscape. The role of wind erosion in today’s north-west European landscapes is, besides in coastal dunes, mainly related to arable fields (on light sandy soils), and to some active remnants of the inland drift-sand areas. In both latter cases there is an urgent need to manage the wind-erosion process. The aim of this PhD thesis is to develop management tools and strategies to control unwanted and wanted wind erosion. On arable land the main objective of managing the wind erosion process is to minimize the on- and off-site damage by reducing erosion risk. The extent, frequency, intensity of wind erosion events, and thereby their on-site and off-site effects, is controlled by soil characteristics, climate and human activities. Field surveys in areas with light sandy soils in four European countries showed that the erosion risk on agricultural land on light sandy soils is controlled by the cropping system, openness of the landscape and farmers practices. Scenario runs with the WEELS wind erosion model give insight into the general change in erosion risk per month. The simulations point to major changes in erosion risk for changes in a wind-break network, but relatively small changes in erosion risk for the tested cropping systems and climate-change scenario’s. With this information, the possible consequences for on-site and off-site damage can be estimated, and from this estimation, additional (policy) measures for controlling wind erosion can be formulated for the region in question. There are enough effective land-management techniques available to minimise the erosion risk to an acceptable level. Voluntary measures based on good agricultural practice work well in a cropping system with high valuable crops and farmers financial benefit from control measures. However, additional policy measures such as mandatory measures and subsidies are needed in case of cropping systems with low or negative net profits and in case of high risk for off-site damage for instance in the period after harvesting when the soil is not longer protected by a crop.

Mots clés : land degradation / agricultural land / wind erosion / land management / nature conservation / landscape conservation

Présentation

Version intégrale (17 Mb)