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Landscape level patterns of grasshopper communities in Inner Mongolia: interactive effects of livestock grazing and a precipitation gradient

Journal Articles & Books
Décembre, 2015
Chine

CONTEXT: Grasshoppers are a dominant herbivore assemblage globally and play an important role for ecosystem nutrient cycling. Yet, we lack a strong understanding of the relationship between grasshopper diversity and plant community composition at the landscape scale. OBJECTIVE: Our aim was to test landscape scale relationships between plant and grasshopper communities. METHODS: We used a large-scale, replicated experiment at four sites, including grazed and protected pastures across a 350 km transect and 200–400 mm precipitation gradient in the steppes of Inner Mongolia, China.

Grazing impacts on the susceptibility of rangelands to wind erosion: The effects of stocking rate, stocking strategy and land condition

Journal Articles & Books
Décembre, 2015
Australie

An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid rangelands. Livestock production is thought to increase the susceptibility of the rangelands to wind erosion by reducing vegetation cover and modifying surface soil stability. However, research is yet to quantify the impacts of grazing land management on the erodibility of the Australian rangelands, or determine how these impacts vary among land types and over time.

Assessing gender roles in a changing landscape: diversified agro-pastoralism in drylands of West Pokot, Kenya

Journal Articles & Books
Décembre, 2015
Kenya

Previous studies in drylands have shown that while gender roles are becoming more flexible, privatization and formalization of land tenure tends to marginalize women in drylands while environmental degradation leads to differential changes in gender workload. Chepareria, a ward in West Pokot County, has undergone the above-mentioned tenure and environmental changes and is nowadays dominated by private enclosures as a land management approach.

What lies beneath: detecting sub‐canopy changes in savanna woodlands using a three‐dimensional classification method

Journal Articles & Books
Décembre, 2015

QUESTION: Increasing population pressure, socio‐economic development and associated natural resource use in savannas are resulting in large‐scale land cover changes, which can be mapped using remote sensing. Is a three‐dimensional (3D) woody vegetation structural classification applied to LiDAR (Light Detection and Ranging) data better than a 2D analysis to investigate change in fine‐scale woody vegetation structure over 2 yrs in a protected area (PA) and a communal rangeland (CR)? LOCATION: Bushbuckridge Municipality and Sabi Sand Wildtuin, NE South Africa.

Desertification, land use, and the transformation of global drylands

Journal Articles & Books
Décembre, 2015

Desertification is an escalating concern in global drylands, yet assessments to guide management and policy responses are limited by ambiguity concerning what this term means and what processes are involved. In order to provide greater clarity, we propose that desertification assessments be placed within a state change-land use change (SC-LUC) framework. SC-LUC views desertification as state change occurring within the context of particular land uses (such as rangeland or cropland) and interacting with land use change.

Integrated climate and land use change scenarios for California rangeland ecosystem services: wildlife habitat, soil carbon, and water supply

Journal Articles & Books
Décembre, 2015

CONTEXT: In addition to biodiversity conservation, California rangelands generate multiple ecosystem services including livestock production, drinking and irrigation water, and carbon sequestration. California rangeland ecosystems have experienced substantial conversion to residential land use and more intensive agriculture.

Pollen‐based quantitative reconstructions of Holocene regional vegetation cover (plant‐functional types and land‐cover types) in Europe suitable for climate modelling

Journal Articles & Books
Décembre, 2015
Irlande
Europe

We present quantitative reconstructions of regional vegetation cover in north‐western Europe, western Europe north of the Alps, and eastern Europe for five time windows in the Holocene [around 6k, 3k, 0.5k, 0.2k, and 0.05k calendar years before present (bp)] at a 1° × 1° spatial scale with the objective of producing vegetation descriptions suitable for climate modelling.

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.

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.

Dynamics of land use and land cover and its effects on hydrologic responses: case study of the Gilgel Tekeze catchment in the highlands of Northern Ethiopia

Journal Articles & Books
Décembre, 2015
Éthiopie

Unprecedented land use and land cover (LULC) changes in the Gilgel Tekeze catchment of the upper Nile River basin in Ethiopia may have far-reaching consequences for the long-term sustainability of the natural resources base. This study analyzed the dynamics and hydrologic effects of LULC changes between 1976 and 2003 as shown in satellite imagery. The effects of these LULC changes on the hydrologic response were investigated using the WetSpa model to estimate spatially distributed average annual evapotranspiration, surface runoff, and groundwater recharge.

Impacts of agricultural land-use dynamics on erosion risks and options for land and water management in Northern Mongolia

Journal Articles & Books
Décembre, 2015
Mongolie

In Mongolia, nomadic herders have successfully been grazing livestock for more than a millennium. However, in recent years, concerns have increased that changes in management and higher livestock stocking rates may negatively affect vegetation and increase soil erosion, overland flow and sediment load of rivers. In addition, ambitious agricultural policies increase the intensity of agricultural land use thus enforcing a conversion of grassland to agricultural land which is far more susceptible to erosion.

Serological evidence of camel exposure to peste des petits ruminants virus (PPRV) in Nigeria

Journal Articles & Books
Décembre, 2015
Nigéria
Afrique

Peste des petits ruminants (PPR), a viral disease of sheep and goats, is endemic in Nigeria. There are reports indicating the involvement of peste des petits ruminants virus (PPRV), the causative agent of PPR, in a camel respiratory syndrome in Africa. Considering that camels share the same grazing land and drinking points with other ruminants, this study was undertaken to determine the seroprevalence and extent of PPRV antibodies in Nigerian camels. A total of 1517 camel sera samples were collected from four states (Borno, Kano, Kastina and Sokoto).