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Doubly segmented proxy images for multi-scale landscape ecology and ecosystem health

Journal Articles & Books
декабря, 2003

Multi-band remotely sensed image data contain information on landscape pattern and temporal changes that are greatly underutilized in this technological era when monitoring of disturbance and ecological dynamics is increasingly important to address questions regarding sustainability of ecosystem health and climate change.

Potentials and constraints of the farmer-to-farmer programme for environmental protection in Nicaragua

Journal Articles & Books
декабря, 2003
Nicaragua

The natural environment in Nicaragua has been damaged by rural development policies geared for the export of cash crops, by uneven land distribution and the near absence of concerns about the environmental effects of the prevailing model of development. The demands made by market forces for the export of primary materials have been reasons for land degradation in the big farms, and the need to survive a poverty stricken existence has forced the peasantry to damage the marginal and fragile land they worked.

Rangeland development of the Mu Us Sandy Land in semiarid China: an analysis using Landsat and NOAA remote sensing data

Journal Articles & Books
декабря, 2003
China

Degradation of the dry semiarid ecosystems in the Mu Us Sandy Land of north central China was explored using high-resolution satellite images from 1978, 1987 and 1996. This study monitored both changes in grassland biomass production and reclamation activities to detect the nature and scale of land degradation since major economic reforms were introduced in 1978. The position of the high-resolution images within the vegetation cycles was inspected from National Oceanographic and Atmospheric Administration (NOAA) NDVI images at 10-day repetition and seasonal precipitation patterns.

causes and spatial pattern of land degradation risk in southern Mauritania using multitemporal AVHRR-NDVI imagery and field data

Journal Articles & Books
декабря, 2003
Mauritania
Chad

Multitemporal 1 km NOAA/AVHRR Normalized Difference Vegetation Index (NDVI) maximum composite imagery was utilized in combination with rainfall, soil types, and field survey data on dominant rural activities to assess the risk of land degradation in southern Mauritania. Mauritania is one of eight continental West African Sahel countries that stretch from Chad to the northwestern Atlantic coast, and from the southern fringe of the Sahara Desert to the northern limit of the Sudanian climatic zone.

Accessibility as a determinant of landscape transformation in western Honduras: linking pattern and process

Journal Articles & Books
декабря, 2003
Honduras

This study evaluates the relationship between landscape accessibility and land cover change in Western Honduras, and demonstrates how these relationships are influenced by social and economic processes of land use change in the region. The study area presents a complex mosaic of land cover change processes that involve approximately equal amounts of reforestation and deforestation.

From social-enquiry to decision support tools: towards an integrative method in the mediterranean rural environment

Journal Articles & Books
декабря, 2003

Policy-relevant approaches to assessing land-use change must be based upon a number of transdisciplinary mechanisms. This approach demands a number of skills—social enquiry, modelling and soft complex systems thinking, which are necessary to facilitate an effective cross-disciplinary dialogue. Underpinning the development of these transdisciplinary skills, and the acceptance of systems as complex and subject to multiple interpretations, is the need to move away from the desire to predict and towards enhancing the capacity to adapt.

Factors contributing to the marginalization of shifting cultivation in north-east India: micro-scale issues

Journal Articles & Books
декабря, 2003
India

Shifting cultivation, locally known as jhum, is the predominant agricultural practice for most communities inhabiting the uplands of north-east India. The negative impacts of the practice on forest and biological resources, soil erosion and land degradation have been a serious concern for several decades now to administrators and planners as well as to the academic community. In the current context, the practice has undergone drastic changes and has become increasingly unviable, gradually leading to the marginalization of farmers practising it.

Scale-dependent effects of grazing on rangeland degradation in northern Kenya: a test of equilibrium and non-equilibrium hypotheses

Journal Articles & Books
декабря, 2003
Kenya

This study employs scale-dependence as an analytical approach to understanding effects of livestock grazing on rangeland degradation in northern Kenya. It used extensive datasets previously collected from 13 200 km2 rangelands where grazing pressure gradients of livestock (varied from none, light, moderate, heavy and very heavy grazing) in conjunction with seasonality across different ecological scales influenced plant responses and probably contributed to land degradation.

investigation of the physical and socioeconomic determinants of soil erosion in the Hararghe Highlands, eastern Ethiopia

Journal Articles & Books
декабря, 2003
Ethiopia

The vicious poverty–environmental spiral commonly exists due to the interconnectedness of the socioeconomic aspects of farmers and land degradation. The socioeconomic situation of farmers affects their capabilities to implement environmentally viable soil and water conservation measures. These situations include farm practices and attitudes toward rational use of resources. An observational study was conducted to have an insight of the perception of farmers about the danger of gully erosion and their willingness to adopt new improved soil and water conservation measures.

relationship between land use and soil erosion in the communal lands near Peddie town, Eastern Cape, South Africa

Journal Articles & Books
декабря, 2003
South Africa
Southern Africa

The origins and development of severe forms of erosion are traced in the communal villages located in a part of the dividing ridge between the Great Fish and Keiskamma rivers near Peddie town, Eastern Cape, South Africa. Progressive changes in land use and soil erosion distribution are reconstructed by analysing sequential aerial photographs of the area between 1938 and 1988. The distributions of the two phenomena are mapped and quantified at the different dates using PC ARC/INFO GIS. Observable soil erosion is confined to the communal lands at all the dates.

Case studies in the conservation of biodiversity: degradation and threats

Journal Articles & Books
декабря, 2003

The rating of biodiversity in arid and semiarid regions on the basis of ecological function and genetic traits of adaptation to severe environmental stresses produces significantly higher values, than that based solely on the commonly applied structural criteria of forms of life and levels of organization.