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Issuesdégradation des terresLandLibrary Resource
There are 2, 371 content items of different types and languages related to dégradation des terres on the Land Portal.
Displaying 613 - 624 of 1119

Land Degradation Analysis on Coastal Area of Ampara District

Journal Articles & Books
Octobre, 2013
Sri Lanka

The island of Sri Lanka is free from serious natural hazards such as volcanic activity and earthquakes resulting from climatic extremes, but there are impacts of many natural disasters, such as landslides, floods and droughts, the intensity and frequency of which are increasing due to human interventions. Some areas of Sri Lanka are also periodically subject to cyclones that occur due to climatic conditions and geographical locations.Land degradation denotes all natural or anthropogenic processes that diminish or impair productivity of land.

Spatial assessment of soil erosion risk using RUSLE and GIS techniques

Journal Articles & Books
Décembre, 2015
Jordanie

Soil erosion by water is considered a major cause for land degradation in Jordan, where 0.14 cm of productive top soil is eroded annually. This investigation is intended to estimate the annual soil loss in Wadi Kerak watershed, and to examine the spatial patterns of soil loss and intensity, as an essential procedure for proper planning of conservation measures. To achieve these objectives, the revised universal soil loss equation (RUSLE) model has been applied in a geographical information system framework.

Effects of vegetation restoration types on soil quality in Yuanmou dry-hot valley, China

Journal Articles & Books
Décembre, 2013
Chine

Soil erosion has resulted in serious land degradation in Yuanmou dry-hot valley, Yunnan province, China. Vegetation restoration had been widely developed in this hot and arid area. In this work we investigate the quality of rhizosphere soils under four restoration species in the towns of Zuolin (gully bed) and Yuanma (slope area). The vegetation included two trees [ Leucaena leucocephala (Lam.) de Wit. and Eucalyptus camaldulensis L.] for the slope area, one shrubland [ Dodonaea viscosa (Linn.) Jacq.

Desertification assessment and mapping in the Russian Federation

Journal Articles & Books
Décembre, 2011
Fédération de Russie

For the first time assessment and mapping of desertification have been performed in Russia at the 1 : 2500000 scale using data of geometrical sounding of the earth and in accordance with the approaches recommended by the United Nations Convention to Combat Desertification (UNCCD). It is shown that desertified areas, areas experiencing desertification, and areas threatened by desertification occupy about 1250000 km2. Nineteen causes of changes in natural and natural-artificial systems, seven degradation trends, and three progradation trends are recognized.

Modeling the long-term natural regeneration potential of woodlands in semi-arid regions to guide restoration efforts

Journal Articles & Books
Décembre, 2014

Understanding forest regeneration at sites previously used for agriculture underlies the establishment of science-based woodlands management policies. This is especially relevant in semi-arid areas, where the tree cover is critical in ameliorating the effects of aridity and in preventing desertification and land degradation. Natural regeneration in semi-arid areas occurs very slowly, which in part explains why it has hardly been studied.

Biotic and Abiotic Changes in Ecosystem Structure over a Shrub-Encroachment Gradient in the Southwestern USA

Journal Articles & Books
Décembre, 2010
États-Unis d'Amérique

In this study, we investigate changes in ecosystem structure that occur over a gradient of land-degradation in the southwestern USA, where shrubs are encroaching into native grassland. We evaluate a conceptual model which posits that the development of biotic and abiotic structural connectivity is due to ecogeomorphic feedbacks. Three hypotheses are evaluated: 1. Over the shrub-encroachment gradient, the difference in soil properties under each surface-cover type will change non-linearly, becoming increasingly different; 2.

Land Degradation Analysis on Coastal Area of Ampara District

Journal Articles & Books
Octobre, 2013
Sri Lanka

The island of Sri Lanka is free from serious natural hazards such as volcanic activity and earthquakes resulting from climatic extremes, but there are impacts of many natural disasters, such as landslides, floods and droughts, the intensity and frequency of which are increasing due to human interventions. Some areas of Sri Lanka are also periodically subject to cyclones that occur due to climatic conditions and geographical locations.Land degradation denotes all natural or anthropogenic processes that diminish or impair productivity of land.

Hidden Cost of Eating Meat in South Africa: What Every Responsible Consumer Should Know

Journal Articles & Books
Décembre, 2015
Afrique du Sud
Afrique australe

Meat production in South Africa is on an increasing trend. In South Africa rising wealth, urbanisation and a growing middle class means South Africans are eating more processed and high-protein foods, especially meat and dairy products. These foods are more land- and water-intensive than fruit, vegetable and grain crops, and further stress existing resources. Traditional agricultural farms cannot keep up with the increasing demand for animal products and these farms are being replaced with concentrated animal feeding operations.

Agricultural Land Degradation and Salinization in Shamsabad Region, Qom Province, Iran

Journal Articles & Books
Janvier, 2009
Iran

Salinization and alkalization are considered spatiotemporal dynamic soil degradation processes. In order to investigate the effects of agricultural activities on land degradation and soil salinity, Shamsabad area in Qom province was selected. Aerial photos (1955) and satellite images (1990-2002) were used to examine the changes in land use. Soil samples were collected from 25 locations in the study area from 0-50 cm and 51-100 cm depth at each location. For comparative purposes, sampling locations in this study were similar to locations used for salinity study in 1983.

Mapping and Monitoring Cheatgrass Dieoff in Rangelands of the Northern Great Basin, USA ☆,☆☆,★

Journal Articles & Books
Décembre, 2015
États-Unis d'Amérique

Understanding cheatgrass (Bromus tectorum) dynamics in the Northern Great Basin rangelands, USA, is necessary to effectively manage the region's lands. This study's goal was to map and monitor cheatgrass performance to identify where and when cheatgrass dieoff occurred in the Northern Great Basin and to discover how this phenomenon was affected by climatic, topographic, and edaphic variables. We also examined how fire affected cheatgrass performance.

methodological approach for deriving regional crop rotations as basis for the assessment of the impact of agricultural strategies using soil erosion as example

Journal Articles & Books
Décembre, 2013

Regarding increasing pressures by global societal and climate change, the assessment of the impact of land use and land management practices on land degradation and the related decrease in sustainable provision of ecosystem services gains increasing interest. Existing approaches to assess agricultural practices focus on the assessment of single crops or statistical data because spatially explicit information on practically applied crop rotations is mostly not available.

Soil bacterial diversity in degraded and restored lands of Northeast Brazil

Journal Articles & Books
Décembre, 2014

Land degradation deteriorates biological productivity and affects environmental, social, and economic sustainability, particularly so in the semi-arid region of Northeast Brazil. Although some studies exist reporting gross measures of soil microbial parameters and processes, limited information is available on how land degradation and restoration strategies influence the diversity and composition of soil microbial communities.