72 research outputs found

    Unmanned Aerial Vehicle (UAV) for monitoring soil erosion in Morocco

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    This article presents an environmental remote sensing application using a UAV that is specifically aimed at reducing the data gap between field scale and satellite scale in soil erosion monitoring in Morocco. A fixed-wing aircraft type Sirius I (MAVinci, Germany) equipped with a digital system camera (Panasonic) is employed. UAV surveys are conducted over different study sites with varying extents and flying heights in order to provide both very high resolution site-specific data and lower-resolution overviews, thus fully exploiting the large potential of the chosen UAV for multi-scale mapping purposes. Depending on the scale and area coverage, two different approaches for georeferencing are used, based on high-precision GCPs or the UAV’s log file with exterior orientation values respectively. The photogrammetric image processing enables the creation of Digital Terrain Models (DTMs) and ortho-image mosaics with very high resolution on a sub-decimetre level. The created data products were used for quantifying gully and badland erosion in 2D and 3D as well as for the analysis of the surrounding areas and landscape development for larger extents

    Monitoring soil erosion in the Souss basin, Morocco, with a multiscale object-based remote sensing approach using UAV and satellite data

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    This article presents a multiscale approach for detecting and monitoring soil erosion phenomena (i.e. gully erosion) in the agro-industrial area around the city of Taroudannt, Souss basin, Morocco. The study area is characterized as semi-arid with an annual average precipitation of 200 mm. Water scarcity, high population dynamics and changing land use towards huge areas of irrigation farming present numerous threats to sustainability. The agro-industry produces citrus fruits and vegetables in monocropping, mainly for the European market. Badland areas strongly affected by gully erosion border the agricultural areas as well as residential areas. To counteract the significant loss of land, land-leveling measures are attempted to create space for plantations and greenhouses. In order to develop sustainable approaches to limit gully growth the detection and monitoring of gully systems is fundamental. Specific gully sites are monitored with unmanned aerial vehicle (UAV) taking small-format aerial photographs (SFAP). This enables extremely high-resolution analysis (SFAP resolution: 2-10 cm) of the actual size of the gully channels as well as a detailed continued surveillance of their growth. Transferring the methodology on a larger scale using Quickbird satellite data (resolution: 60 cm) leads to the possibility of a large-scale analysis of the whole area around the city of Taroudannt (Area extent: ca. 350 km²). The results will then reveal possible relationships of gully growth and agro-industrial management and may even illustrate further interdependencies. The main objective is the identification of areas with high gully-erosion risk due to non-sustainable land use and the development of mitigation strategies for the study area

    Assessing environmental changes in abandoned German vineyards. Understanding key issues for restoration management plans

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    Land degradation in vineyards is a big concern which should be considered by farmers, enterprises and policymakers. Due to intense tillage, the use of herbicides and heavy machinery, vine plantations are registering a decrease in soil fertility and, subsequently, in productivity. Recently, farmers have decided to abandon the vineyards, but any restoration planning is being carried out to recover biodiversity or to reduce soil and water losses. Nowadays, there is no information about environmental changes after the abandonment in terms of possible soil property changes and erosion in Central European vineyards such as in Germany. Therefore, the main aims of this preliminary study were to compare: i) soil properties and soil profiles of one cultivated vineyard and an abandoned one; and, ii) to assess the activation of soil erosion processes using a small portable rainfall simulator. Our results showed that the vineyard registered several differences in soil properties among slope positions and soil profile characteristics due to tillage and trampling effects, showing clear marks of compaction and soil detachment in the lower parts. Also, in this cultivated field, higher means and maxima of soil losses (g m-2) and sediment concentration (g l-1) values than in the abandoned plot were quantified, being the main driving factors the vegetation cover and the inclination. On the other hand, in the abandoned vine plantation, a rapid homogenization of soil profiles and soil properties were found along the hillslope, where a deeper organic horizon was consistently developed above a compacted and rocky horizon, which was generated during the cultivation phase. Due to the high compaction due to the machinery cultivation and the difficulties for the roots to make deep into the soil, the infiltration defaulted and the amount of runoff and runoff coefficient were higher in the abandoned plots than in the cultivated ones

    Rainfall-simulated quantification of initial soil erosion processes in sloping and poorly maintained terraced vineyards - Key issues for sustainable management systems

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    In the context of the Sustainable Development Goals (SDG), understanding landscape evolution is essential to design long-term management plans. In agricultural fields, such as the vineyards on steep slopes, the terraces offer one of the most important morphological changes. However, it is not clear if the poorly managed agricultural terraces are optimal to reduce soil erosion and overland flow, although the trafficability is improved. Therefore, the main aim of this research is to compare the differences between initial soil erosion processes on poorly managed terraced vineyards and sloping vineyards at the pedon scale, considering the key role of the SSC (Soil Surface Components). To achieve this goal, twenty-six rainfall simulations were performed, considering the inclination, vegetation and stone covers, and surface roughness. Our research was carried out in the sloping vineyards (>20°) of the Almáchar municipality, in the Montes de Málaga (Spain). Those vineyards are characterized by bare soils, low organic matter and high rock fragment contents. Our results showed that higher soil losses (42.2 g m−2 vs 9.4 g m−2) and runoff (4.9 l m−2 vs 1.6 l m−2) were detected in the plots of the poorly managed terraced vineyard than in the sloping one. Moreover, the time to runoff generation was lower in the poorly conserved terraces (232 s) than in the sloping vineyard (679 s), showing a faster saturation capacity. The SSC considered as the key factors were the reduction of the stone cover and an increase of roughness. As a conclusion, we confirm that the imminent transformation from sloping vineyards into terraced fields could lead several land degradation processes if a poor management is carried out, and no control measures are applied during the process, such as the conservation of stone walls or vegetation cover above the embankment, which is not in compliance with the SDG.Ministerio de Educación, Cultura y Deporte from Spain for the financial support of the FPU15/0149

    High variability of soil erosion and hydrological processes in Mediterranean hillslope vineyards (Montes de Málaga, Spain)

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    Conventional Mediterranean vineyards from the Montes de Málaga (Axarquía region, Spain) are characterized by high average temperatures, extreme rainfall events during autumn and winter, elevated stoniness and steep slopes (20–50°). Traditionally, several problems of high soil loss, rill and ephemeral gully generation, and elevat- ed runoff are observed by farmers, which are increasing land degradation processes and a decrease of the productivity. According to this, the main aims of this paper were: i) to quantify the initial soil loss, surface flow and infiltration processes; ii) to characterize and describe the hydrological and geomorphological dynamics; iii) to detect the key factors, which control the soil erosion processes. For this purpose, a combined methodology was applied, using soil analysis, a small portable rainfall simulator and a Guelph permeameter on one experimental plot cultivated with vineyards with steep slopes. Results showed a high variability of soil erosion and permeability processes. Soil analysis showed an elevated concentration of silt particles and stoniness, with higher contents of sand particles between 0 and 5 cm, and clays from 5 cm. With a Guelph permeameter, high average of permeability and saturated hydraulic conductivity with elevated standard deviation were observed. Furthermore, an increase of these parameters from the upper to the foot slope was reg- istered. By using rainfall simulations, on the upper and the foot slope positions the highest runoff coefficient and soil loss were registered. The most elevated peak of sediment concentration was obtained on the middle slope. In general, high infiltration coefficients between 66.5 and 100% were observed. In conclusion it was observed that the activation of the soil erosion processes was due to the distribution of the surface soil components (high roughness, several cracks and high stoniness and silt content), the steep slopes and the impact of the soil traditional tillage practices. These Mediterranean hillslope vineyards registered a mixed Hortonian-Hewlettian model, which combines surface and sub-surface flow conditioned by the micro-topo- graphical changes and its saturation degree

    Étude des processus de géo-morphodynamique dans les vignobles cultivés sur les pentes en circulation Ruwer Valley (Allemagne) champs de différentes techniques

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    The present work pretends to examine the erosive soil response of vineyards on the high steeps in the Ruwer Valley (Germany) with different methods. The experiments were developed between September and December along three different land management situation of the soil: before, during and after vintage. Firstly, with geometrical rill monitoring we quantify the lateral (7 to 13 cm) and vertical (1 to 4 cm) erosion. The high variability on the hydro-geomorphological process along the steep slopes is confirmed by the soil transport. Elevated infiltration rates were noted using the runoff curve number and rainfall simulations; however, the final results were different. Finally, the negative impact of the erosion by anthropic activities was confirmed with two methods: RUSLE (Revised Universal Soil Loss Equation) and using botanic marks on the grape-vines. With the first techniques, 11.28 t ha-1 and respectively with the second 3.4 t ha-1 soil erosion rate was calculated.El presente trabajo pretende examinar la respuesta erosiva del suelo en áreas cultivadas de viñedos sobre laderas en pendientes elevadas en el Valle del Ruwer (Alemania) a través de diferentes técnicas. Los experimentos se desarrollan entre los meses de septiembre y diciembre durante diferentes épocas de manejo del suelo: antes, durante y después de la vendimia. En primer lugar, se realiza un análisis de la variación geométrica de tres rills para cuantificar su expansión lateral (de 7 a 13 cm) y vertical (1 a 4 cm). El movimiento del suelo confirma una elevada variabilidad en los procesos hidro-geomorfológicos de la ladera. A continuación, a través del cálculo del coeficiente teórico de escorrentía a partir del número de curva y lluvias simuladas en diferentes épocas del año, se observan unas elevadas tasas de infiltración, aunque con resultados muy diferentes entre técnicas. Por último, con el cálculo de la RUSLE (Revised Universal Soil Loss Ecuation) y el análisis de las marcas botánicas en los tocones de las parras, se calcula el impacto negativo de la erosión con el manejo agrícola del ser humano sobre los suelos de los viñedos. Con ambos métodos, se han obtenido 11.28 t ha-1 y 3.4 t ha-1 año de pérdida de suelo, respectivamente.Ce document vise à déterminer la réponse de l’érosion des sols dans les zones cultivées de vignes dans la Vallée de Ruwer (Allemagne) par le biais de différentes techniques. Tout d’abord, une survie géométrique rills est réalisée afin de quantifier l›expansion verticale (1-4 cm) et latérale (7 à 13 cm) lors des différentes périodes de la gestion de l›utilisation des terres (entre Septembre et Décembre): avant, pendant et après la récolte. En outre, avec le calcul théorique du coefficient de ruissellement avec le nombre de courbe et des simulations de pluies le longs de différentes saisons ont été confirmée des élevés taux d›infiltration. Finalement, le calcul de la RUSLE (Universal Soil Loss révisée Equation) et l›analyse des marques botaniques sur les souches de vignes, l›impact négatif de la gestion agricole de l›homme sur le sol du vignoble est confirmée. Avec les deux méthodes 11.28 t ha-1 et 3.4 t ha-1 sont perdu respectivement

    Soil erosion processes in european vineyards: a qualitative comparison of rainfall simulation measurements in Germany, Spain and France

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    Small portable rainfall simulators are considered a useful tool to analyze soil erosion processes in cultivated lands. European research groups in Spain (Valencia, Málaga, Lleida, Madrid and La Rioja), France (Reims) and Germany (Trier) have used different rainfall simulators (varying in drop size distribution and fall velocities, kinetic energy, plot forms and sizes, and field of application) to study soil loss, surface flow, runoff and infiltration coefficients in different experimental plots (Valencia, Montes de Málaga, Penedès, Campo Real and La Rioja in Spain, Champagne in France and Mosel-Ruwer valley in Germany). The measurements and experiments developed by these research teams give an overview of the variety of methodologies used in rainfall simulations to study the problem of soil erosion and describe the erosion features in different climatic environments, management practices and soil types. The aims of this study are: (i) to investigate where, how and why researchers from different wine-growing regions applied rainfall simulations with successful results as a tool to measure soil erosion processes; (ii) to make a qualitative comparison about the general soil erosion processes in European terroirs; (iii) to demonstrate the importance of the development of standard method for measurement of soil erosion processes in vineyards, using rainfall simulators; and (iv) and to analyze the key factors that should be taken into account to carry out rainfall simulations. The rainfall simulations in all cases allowed infiltration capacity, susceptibility of the soil to detachment and generation of sediment loads to runoff to be determined. Despite using small plots, the experiments were useful to analyze the influence of soil cover to reduce soil erosion, to make comparisons between different locations, and to evaluate the influence of different soil characteristics. The comparative analysis of the studies performed in different study areas points out the need to define an operational methodology to carry out rainfall simulations, which allows us to obtain representative and comparable results and to avoid errors in the interpretation in order to achieve comparable information about runoff and soil los

    Treatment of Fabry Disease: Outcome of a Comparative Trial with Agalsidase Alfa or Beta at a Dose of 0.2 mg/kg

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    Two different enzyme preparations, agalsidase alfa (Replagal(TM), Shire) and beta (Fabrazyme(TM), Genzyme), are registered for treatment of Fabry disease. We compared the efficacy of and tolerability towards the two agalsidase preparations administered at identical protein dose in a randomized controlled open label trial.Thirty-four Fabry disease patients were treated with either agalsidase alfa or agalsidase beta at equal dose of 0.2 mg/kg biweekly. Primary endpoint was reduction in left ventricular mass after 12 and 24 months of treatment. Other endpoints included occurrence of treatment failure (defined as progression of cardiac, renal or cerebral disease), glomerular filtration rate, pain, anti-agalsidase antibodies, and globotriaosylceramide levels in plasma and urine. After 12 and 24 months of treatment no reduction in left ventricular mass was seen, which was not different between the two treatment groups. Also, no differences in glomerular filtration rate, pain and decline in globotriaosylceramide levels were found. Antibodies developed only in males (4/8 in the agalsidase alfa group and 6/8 in the agalsidase beta group). Treatment failure within 24 months of therapy was seen in 8/34 patients: 6 male patients (3 in each treatment group) and 2 female patients (both agalsidase alfa). The occurrence of treatment failures did not differ between the two treatment groups; chi(2) = 0.38 p = 0.54.Our study revealed no difference in reduction of left ventricular mass or other disease parameters after 12 and 24 months of treatment with either agalsidase alfa or beta at a dose of 0.2 mg/kg biweekly. Treatment failure occurred frequently in both groups and seems related to age and severe pre-treatment disease.International Standard Randomized Clinical Trial ISRCTN45178534 [http://www.controlled-trials.com/ISRCTN45178534]
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