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Appraising and selecting conservation measures to mitigate desertification and land degradation based on stakeholder participation and global best practices

Journal Articles & Books
Décembre, 2009

Most desertification research focuses on degradation assessments without putting sufficient emphasis on prevention and mitigation strategies, although the concept of sustainable land management (SLM) is increasingly being acknowledged. A variety of already applied conservation measures exist at the local level, but they are not adequately recognised, evaluated and shared, either by land users, technicians, researchers, or policy makers. Likewise, collaboration between research and implementation is often insufficient.

Future of Tropical Species on a Warmer Planet

Journal Articles & Books
Décembre, 2009
Afrique occidentale

Modern global temperature and land cover and projected future temperatures suggest that tropical forest species will be particularly sensitive to global warming. Given a moderate greenhouse gas emissions scenario, fully 75% of the tropical forests present in 2000 will experience mean annual temperatures in 2100 that are greater than the highest mean annual temperature that supports closed-canopy forest today. Temperature-sensitive species might extend their ranges to cool refuges, defined here as areas where temperatures projected for 2100 match 1960s temperatures in the modern range.

Land degradation and soil and water conservation in tropical highlands

Journal Articles & Books
Décembre, 2009
Éthiopie

Land degradation is not uniform, even in the same landscape, but nevertheless an overall consensus seems to grow on the fact that many areas are under way of rehabilitation. It is a debateable question whether the improving areas are improving because of interventions--or whether this has more to do with processes of innovation and adaptation.

Desertification? Northern Ethiopia re-photographed after 140 years

Journal Articles & Books
Décembre, 2009
Éthiopie

A collection of sepia photographs, taken during Great Britain's military expedition to Abyssinia in 1868, are the oldest landscape photographs from northern Ethiopia, and have been used to compare the status of vegetation and land management 140 years ago with that of contemporary times. Thirteen repeat landscape photographs, taken during the dry seasons of 1868 and 2008, were analyzed for various environmental indicators and show a significant improvement of vegetation cover.

Effects of crop abandonment and grazing exclusion on available soil water and other soil properties in a semi-arid Mongolian grassland

Journal Articles & Books
Décembre, 2009

Improper cropping and overgrazing have led to land degradation in semi-arid regions, resulting in desertification. During desertification, vegetation changes have been widely observed, and are likely controlled to some extent by soil water. The purpose of this study was to investigate changes in soil physical properties, organic C, and vegetation induced by land-use changes, with special reference to the dynamics of available soil water.

Land use and disturbance effects on the dynamics of natural ecosystems of the Monte Desert: Implications for their management

Journal Articles & Books
Décembre, 2009

The complex interactions between human activity and natural processes determine non-linear dynamics in ecosystems that can difficult their management. Human settlements in arid lands contribute to the modification of disturbance regimes, including the introduction of new disturbances and the elimination of others. In consequence, they can alter the functional mechanisms that allow systems to overcome limiting factors, leading to desertification.

Antibiotic resistance profiles of soil bacterial communities over a land degradation gradient

Journal Articles & Books
Décembre, 2009
Thaïlande

This study profiled soils over a land degradation gradient to obtain formulae as integrative measures for describing the gradient as a result of deforestation in Thailand. We applied antibiotic resistance most-probable-number profiling to the soil bacterial communities, and then described the gradient. Soil samples were collected on the gradient represented by dry evergreen forest (the original vegetation), dry deciduous forest (moderately disturbed) and bare ground (the most degraded) in February (dry season), March (shortly after temporal precipitation) and June (rainy season) 2001.

CLIMATIC NEEDS OF AUTUMN BARLEY AND CLIMATE CHANGE

Journal Articles & Books
Décembre, 2009

Munkánkban összehasonlító vizsgálatokat végeztünk az őszi árpa fejlődési szakasza¬inak klimatikus igényeiről. A becsült meteorológiai jellemzők átlagosan nem mutatnak nagy változást a közeljövőre – jóllehet a század végére már igen –, de eloszlásuk alakulása a mezőgazdaságban komoly következményekkel járhat. A növény szempontjából azonban az éves és havi átlaghőmérséklet, illetve csapadékösszegek elemzése helyett sokkal több információhoz juthatunk, ha a növény fejlődési szakaszait külön-külön vizsgáljuk.

Current and Potential Future Elevational Distributions of Birds Associated with Pinyon-Juniper Woodlands in the Central Great Basin, U.S.A

Journal Articles & Books
Décembre, 2009

We examined the relationship of breeding birds to elevation across and within four adjacent mountain ranges in the central Great Basin, a cold desert in western North America. Data came from 7 years of point counts at elevations from 1,915 to 3,145 m. We focused on eight passerine species that in this region are associated frequently with Pinus monophylla-Juniperus spp. (pinyon-juniper) woodland.

Spatial-based assessment of land use, soil erosion, and water protection in the Jeneberang valley, Indonesia

Journal Articles & Books
Décembre, 2009
Indonésie

Soil erosion by water is considered as one of the most significant forms of land degradation that affects sustained productivity of agricultural land use and water quality. It is influenced by a considerable number of factors (including climate, soil, topography, land use and types of land management), so that the information on the spatial distribution of soil erosion rate and its related effects can be effectively employed as a baseline data for land use development and water protection.

Efficacy of Integrating Herder Knowledge and Ecological Methods for Monitoring Rangeland Degradation in Northern Kenya

Journal Articles & Books
Décembre, 2009
Kenya

The world-wide debate on land degradation in arid lands, usually linked to local land use practices, does not reflect methodological advancements in terms of assessments and monitoring that integrate local communities' knowledge with ecological methods.