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Informal institutions as mechanisms to address challenges in communal grazing land management in Tigray, Ethiopia

Journal Articles & Books
Diciembre, 2011
Etiopía

The role of institutions providing rules, norms and regulations, in addressing challenges in communal resources management has been debated for several decades. This article analyses the role of informal institutions for addressing shortage of grazing land, conflicts among users of communal grazing land and resistance among users to shift from free grazing to zero grazing in Tigray, Ethiopia. We used in depth interviews and focus group discussions for data collection.

Mediterranean water resources in a global change scenario

Journal Articles & Books
Diciembre, 2011
Europa
África septentrional

Mediterranean areas of both southern Europe and North Africa are subject to dramatic changes that will affect the sustainability, quantity, quality, and management of water resources. Most climate models forecast an increase in temperature and a decrease in precipitation at the end of the 21st century. This will enhance stress on natural forests and shrubs, and will result in more water consumption, evapotranspiration, and probably interception, which will affect the surface water balance and the partitioning of precipitation between evapotranspiration, runoff, and groundwater flow.

Post-wildfire soil erosion in the Mediterranean: Review and future research directions

Journal Articles & Books
Diciembre, 2011
Israel
España

Wildfires increased dramatically in frequency and extent in the European Mediterranean region from the 1960s, aided by a general warming and drying trend, but driven primarily by socio-economic changes, including rural depopulation, land abandonment and afforestation with flammable species. Published research into post-wildfire hydrology and soil erosion, beginning during the 1980s in Spain, has been followed by studies in other European Mediterranean countries together with Israel and has now attained a sufficiently large critical mass to warrant a major review.

integrated approach to modelling land-use change on continental and global scales

Journal Articles & Books
Diciembre, 2011

Land-use and land-cover change are important drivers of global environmental change, affecting the state of biodiversity, the global carbon cycle, and other aspects of the earth system. In this article we describe the development of the land-use model LandSHIFT, which aims to simulate land-use and land-cover change on the continental and global scale. The model is based on a “land-use systems” approach, which describes the interplay between anthropogenic and environmental system components as drivers of land-use change.

Desertification in China's Horquin area: a multi-temporal land use change analysis

Journal Articles & Books
Diciembre, 2011
China

China's Horquin area in the northern farming–pastoral transition zone is undergoing rapid land degradation and rangeland modification that is impacting far broader areas as the source of material for dust storms. Multi-temporal Landsat images of the Horquin core area were used to generate a time series of land use covering about a 30-year period, 1975–2003. We show that the physical environment in Horquin deteriorated between 1975 and 2000, although this situation was more controlled after 2000.

Quantifying Rhizosphere Respiration for Two Cool-Season Perennial Forages

Journal Articles & Books
Diciembre, 2011

Understanding the regulation of ecosystem CO2 flux from forage production systems requires knowledge of component fluxes, including photosynthetic uptake and respiratory loss. Experimental separation of soil respiration into heterotrophic and rhizosphere respiration has been difficult, complicating efforts to quantify management and environmental effects on grazing land C sequestration.

Rodent population management at Kansas City International Airport

Journal Articles & Books
Diciembre, 2011
Estados Unidos de América

Birds pose serious hazards at United States airports because of the potential for collisions with aircraft. Raptors, in particular, are hazardous to aircraft safety due to their size, hunting behavior, and hovering and soaring habits. Reduction of rodent populations at an airport may decrease raptor populations in the area and, therefore, reduce risk that raptors pose to aircraft. Rodent populations can be reduced by population management (i.e., use of rodenticides) or by habitat management (i.e., vegetation and land-use management) that reduces the area’s carrying capacity for rodents.

Halland's forests during the last 300 years: a review of Malmström (1939)

Journal Articles & Books
Diciembre, 2011
Suecia

Carl Malmström's historical forest maps of the province of Halland, in south-western Sweden, were published over 70 years ago, but are still important to science and conservation. They show the transformation of a seventeenth century landscape of temperate broadleaves to a landscape dominated by open land and heather (Calluna vulgaris) in the nineteenth century, and to a landscape of coniferous forest plantations in the twentieth century. This article summarizes and reviews the original research, first published in Swedish in 1939.

Cross-fence comparisons: Theory for spatially comprehensive, controlled variable assessment of treatment effects in managed landscapes

Journal Articles & Books
Diciembre, 2011

Historically monitoring of grazing impacts in rangelands has been seriously compromised by the small area, infrequency and variability of field-based sampling plots. Remote sensing of vegetation cover, which can be a surrogate for overall ecosystem condition, permits adequate spatial and temporal monitoring of land condition but can still be compromised by considerable inter and intra-paddock (field) variability. Cross-fence sample pairs control for local clines and patchiness in spatial and temporal variables such as vegetation, landform, soil type, surface-flows, and rainfall.

Denitrification and dissimilatory nitrate reduction to ammonium (DNRA) in a temperate re-connected floodplain

Journal Articles & Books
Diciembre, 2011

The relative magnitudes of, and factors controlling, denitrification and dissimilatory nitrate reduction to ammonium (DNRA) were measured in the soil of a re-connected temperate floodplain divided into four different land management zones (grazing grassland, hay meadow, fritillary meadow and a buffer zone). Soil samples were collected from each zone to measure their respective potentials for nitrate attenuation using ¹⁵N both at the surface and at depth in the soil column and additional samples were collected to measure the lability of the organic carbon.

Quantification of aboveground rangeland productivity and anthropogenic degradation on the Arabian Peninsula using Landsat imagery and field inventory data

Journal Articles & Books
Diciembre, 2011
Omán

The productivity of semi-arid rangelands on the Arabian Peninsula is spatially and temporally highly variable, and increasing grazing pressure as well as the likely effects of climatic change further threatens vegetation resources. Using the Al Jabal al Akhdar mountains in northern Oman as an example, our objectives were to analyse the availability and spatial distribution of aboveground net primary production (ANPP) and the extent and causes of vegetation changes during the last decades with a remote sensing approach.

Grazing intensity monitoring in Northern China steppe: Integrating CENTURY model and MODIS data

Journal Articles & Books
Diciembre, 2011
China

Steppe, an important belt to protect North China from dust storms, is vulnerable and has been degraded in recent decades because of climatic change and heavy grazing. In order to improve steppe management, this study presents a framework for the monitoring of grazing intensity in Xilingol steppe of middle Inner Mongolia, northern China, by integrating the CENTURY ecosystem model-based simulation and remotely sensed MODIS data-based inversion.