1,720,994 research outputs found
Land degradation in agricultural landscapes-Soil erosion by water
Get PDFLand degradation is a well-known problem throughout the world, due to its possible threat to land resources and strict connection with other global environmental issues such as biodiversity and climate. It is widely accepted that the major causes of land degradation include deforestation, soil erosion, overgrazing, inappropriate irrigation, abandonment and/or lack of maintenance of agricultural terraces, land use and cover change, especially because of urban sprawl and commercial development, soil pollution and quarrying. Among land degradation phenomena, soil erosion is one of the most significant issues that negatively influence the agricultural sector. In particular, soil erosion caused by water is one of the most important concern, especially in the Mediterranean area. Among the agricultural landscapes, vineyards deserve attention, because, not only they represent one of the most important crops in terms of income and employment, but they have also demonstrated to constitute, for the Mediterranean areas, the form of agricultural land use that has been causing the highest soil losses. Terraced vineyards deserve a particular mention too. In fact, they represent an important cultural heritage to preserve and if, if not properly maintained, can lead to local instabilities creating hazards for settlements and cultivations, and for the related economy. Although researchers have already dealt with the topic of soil erosion by water in agriculture, there are still some gaps in literature. The processes involved are complex and the analyses can be carried out at different spatial and temporal scales. Indeed, the lack of standardized procedures of collecting data and the variability of temporal and spatial conditions and measurement techniques for the analysis of soil water erosion processes require further research. To overcome these issues, this thesis aims to propose an integrated approach, by means of innovative remote-sensing technologies, field activities, and quantitative analyses to the investigation of soil erosion processes caused by water in agricultural landscapes. Furthermore, this thesis wants also to suggest a possible soil management technique, namely mulching, as an effective solution to mitigate soil and water losses in the before-mentioned environments. Among the remote-sensing technologies, light detection and ranging (LiDAR) and structure-from-motion (SfM) have been applied in this thesis. These have proven to be effective to obtain high-resolution Digital Elevation Models (DEMs). Experimental plots under simulated rainfalls have also been used to quantify and analyze the soil and water losses caused by water. Typical agricultural landscapes, especially Mediterranean vineyards, have been selected as study areas for this thesis
Soil water erosion on Mediterranean vineyards: A review
No full textSoil water erosion on cultivated lands represents a severe threat to soil resources in the world, and especially in
Mediterranean areas, due to their topographic, edaphic and climatic conditions. Among the cultivated lands,
vineyards deserve a particular attention because, aside representing one of the most important crops in terms
of income andemployment, they also have proven to be the formof agricultural use that causes one of the highest
soil losses. Although the topic of soilwater erosion on vineyards has been studied, it still raises uncertainties, due
to the high variability of procedures for data acquisition, which consists into different scales of analysis and
measurement methods. There is still a great gap in knowledge about the effect of triggering factors on soil
water erosion and, so far, an effort to quantify this effect on the Mediterranean viticulture has not been made
yet. Therefore, this paper review aims to (i) develop a documented database on splash, sheet and rill erosion
rates in Mediterranean vineyards, (ii) identify and, if possible, quantify the effect of triggering factors such as
topography, soil properties, rainfall characteristics and soil conservation techniques on soil water erosion, and
(iii) provide suggestions for a more sustainable viticulture. Although the large variability of data, some general
trends between erosion rates and triggering factors could be found, as long as data were categorized according
to the samemeasurement method.However, no general rule uponwhich to consider one triggering factor always
predominant over the others came out. This paper review supports the importance of monitoring soil water
erosion by field measurements to better understand the relationship between the factors. However, protocols
should be established for standardizing the procedure of collecting data and reporting results to enable data
comparison among different study areas
Mulching practices for reducing soil water erosion: A review
No full textAmong the soil conservation practices that are used, mulching has been successfully applied to reduce soil and water
losses in different contexts, such as agricultural lands, fire-affected areas, rangelands and anthropic sites. In these contexts,
soil erosion by water is a serious problem, especially in semi-arid and semi-humid areas of the world. Although
the beneficial effects ofmulching are known, further research is needed to quantify them, especially in areas where soil
erosion by water represents a severe threat. In the literature, there are still some uncertainties about how tomaximize
the effectiveness of mulching to reduce the soil and water loss rates. Given the seriousness of soil erosion by water and
the uncertainties that are still associated with the correct use of mulching, this study review aims to (i) develop a documented
and global database on the use of mulching with vegetative residues; (ii) quantify the effects of mulching on
soil andwater losses based on differentmeasurementmethods and, consequently, different spatial scales; (iii) evaluate
the effects of different types of mulches on soil and water losses based on different measurement methods; and (iv)
provide suggestions for more sustainable soil management. The data published in the literature have been collected.
The results showed the beneficial effects ofmulching in combating soil erosion bywater in all of the environments considered
here, with reduction rates in the average sediment concentration, soil loss and runoff volume that, in some
cases, exceeded 90%. However, the economic feasibility of mulching application was not readily available in the literature.
Therefore, more research should be performed to help both farmers and land managers by providing them with
evidence-based means for implementing more sustainable soil management practices
Smartphones for post-event analysis: a low-cost and easily accessible approach for mapping natural hazards
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Estimation of grazing-induced erosion through remote-sensing technologies in the Autonomous Province of Trento, Northern Italy
No full textLand use change in the last century in the Veneto floodplain: effects on network drainage density, water storage, and related consequences on flood
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