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Displaying 733 - 744 of 2002

Combating Aeolian Desertification in Northern China

Journal Articles & Books
Dezembro, 2015
China

Progress in combating aeolian desertification (land degradation resulting from wind erosion) has been achieved in an agro‐pastoral ecotone of northern China since the mid‐1980s. This paper reviews three common measures used to combat and control aeolian desertification in such regions. In addition, it introduces a case study on the recovery of a degraded semi‐arid ecosystem to provide regional lessons and support theoretical and practical approaches to desertification prevention and reversal on a global scale.

repeat photograph analysis of long‐term vegetation change in semi‐arid South Africa in response to land use and climate

Journal Articles & Books
Dezembro, 2015
África do Sul
África austral

QUESTIONS: How has the vegetation of the major biomes (Grassland, Nama‐karoo, Albany Thicket, Azonal) of southeastern South Africa changed over the course of the 20th century? How do changes in climate and land‐use drivers relate to long‐term changes in vegetation? What are the implications of these findings for land degradation hypotheses and future climate change projections for the region? LOCATION: The biogeographically complex semi‐arid, Karoo Midlands region of the southeastern part of South Africa.

Multi‐Scale Anthropogenic Driving Forces of Karst Rocky Desertification in Southwest China

Journal Articles & Books
Dezembro, 2015
China

Karst rocky desertification (KRD) is a type of land degradation especially prominent in southwest China. This article analyzes the anthropogenic driving forces of KRD at two scales: rural locality and its macro socio‐economic circumstances. At the rural locality scale, the intensive human pressure on land because of a large and fast growing population and unsustainable land use are identified to be the reason for KRD. However, more radical driving forces lie in the farmers' disadvantages in social‐economic circumstances, which compel them to overuse rural land.

Mapping of regional soil salinities in Xinjiang and strategies for amelioration and management

Journal Articles & Books
Dezembro, 2015
China

Information on the spatial distribution of soil salinity can be used as guidance in avoiding the continued degradation of land and water resources by better informing policy makers. However, most regional soil-salinity maps are produced through a conventional direct-linking method derived from historic observations. Such maps lack spatial details and are limited in describing the evolution of soil salinization in particular instances.

Dynamics of soil organic carbon stock in a typical catchment of the Loess Plateau: comparison of model simulations with measurements

Journal Articles & Books
Dezembro, 2015

Land use changes are known to significantly affect the soil C balance by altering both C inputs and losses. Since the late 1990s, a large area of the Loess Plateau has undergone intensive land use changes during several ecological restoration projects to control soil erosion and combat land degradation, especially in the Grain for Green project. By using remote sensing techniques and the Yasso07 model, we simulated the dynamics of soil organic carbon (SOC) stocks in the Yangjuangou catchment of the Loess Plateau.

Agricultural drought trends and mitigation in Tillaberí, Niger

Journal Articles & Books
Dezembro, 2015
Níger
Global

Whether aggravated agricultural drought in the Sahel is related to a changing climate (meteorological drought, i.e., deficit of rainfall or unfavourable rainfall distribution) or to land use and land degradation (soil-water drought, i.e., decreased water infilitration and water holding capacity) is a much-debated issue.

Pollution, habitat loss, fishing, and climate change as critical threats to penguins

Journal Articles & Books
Dezembro, 2015

Cumulative human impacts across the world's oceans are considerable. We therefore examined a single model taxonomic group, the penguins (Spheniscidae), to explore how marine species and communities might be at risk of decline or extinction in the southern hemisphere. We sought to determine the most important threats to penguins and to suggest means to mitigate these threats. Our review has relevance to other taxonomic groups in the southern hemisphere and in northern latitudes, where human impacts are greater.

Adoption intensity of soil and water conservation technologies: a case of South Western Uganda

Journal Articles & Books
Dezembro, 2015
Uganda

Important signs of agricultural land quality deterioration are apparent in many countries, including declining yields and a switch to crops that demand fewer nutrients. This is despite efforts to curb land degradation rates through the years, including the attempt to promote use of soil and water conservation (SWC) technologies. This study was done in Kabale district in the South Western highlands of Uganda. Data analysis was done using cross-sectional data from 338 households.

Long-term impacts of season of grazing on soil carbon sequestration and selected soil properties in the arid Eastern Cape, South Africa

Journal Articles & Books
Dezembro, 2015
África do Sul
África austral

BACKGROUND AND AIMS: The Karoo biomes of South Africa are major feed resources for livestock farming, yet soil nutrient depletion and degradation is a major problem. The objective of this study was to assess impacts of long-term (>75 years) grazing during spring (SPG), summer (SUG), winter (WG) and exclosure (non-grazed control) treatments on soil nutrients, penetration resistance and infiltration tests.

Hydrosalinity and environmental land degradation assessment of the East Nile Delta region, Egypt

Journal Articles & Books
Dezembro, 2015
Egito

Environmental land degradation is a major impediment to the utilization of land in many arid and semi-arid regions of the World and is a major issue in the East Nile Delta (END), Egypt. Waterlogging and salt-affected soil problems have serious implications for irrigated areas leading to socio-economic and agricultural development problems.

Carbon management in dryland agricultural systems. A review

Journal Articles & Books
Dezembro, 2015

Dryland areas cover about 41 % of the Earth’s surface and sustain over 2 billion inhabitants. Soil carbon (C) in dryland areas is of crucial importance to maintain soil quality and productivity and a range of ecosystem services. Soil mismanagement has led to a significant loss of carbon in these areas, which in many of them entailed several land degradation processes such as soil erosion, reduction in crop productivity, lower soil water holding capacity, a decline in soil biodiversity, and, ultimately, desertification, hunger and poverty in developing countries.

Assessment of land degradation and its impact on crop production in the Dry Zone of Myanmar

Journal Articles & Books
Dezembro, 2015
Myanmar

Land degradation in terms of soil degradation is a major environmental issue posing threat to sustainable livelihood in the semi-arid region of Central Myanmar. However, the studies on soil degradation status and its impacts in this region are very scanty. The objective of this study was to determine the impact of land degradation on crop production both in terms of area and yield in the Dry Zone of Myanmar. Remote sensing and geographic information system-based modelling was utilized to assess and map soil erosion rates.