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Issuesutilisation des terresLandLibrary Resource
There are 9, 789 content items of different types and languages related to utilisation des terres on the Land Portal.
Displaying 841 - 852 of 4598

National Assessment of Stressors to Estuarine Fish Habitats in the Contiguous USA

Journal Articles & Books
Décembre, 2015
États-Unis d'Amérique

Estuaries provide vital habitat to a wide variety of fish species, so understanding how human activities impact estuarine habitats has important implications for management and conservation of fish stocks. We used nationwide datasets on anthropogenic disturbance to perform a quantitative assessment of habitat stressors in US estuaries. Habitat stressors were characterized by four categories of indicator datasets: (1) land cover/land use, (2) alteration of river flows, (3) pollution sources, and (4) eutrophication.

Population spatialization in China based on night-time imagery and land use data

Journal Articles & Books
Décembre, 2011
Chine

Population is a key indicator of socioeconomic development, urban planning and environmental protection, particularly for developing countries like China. But, census data for any given area are neither always available nor adequately reflect the internal differences of population. The authors tried to overcome this problem by spatializing the population across China through utilizing integer night-time imagery (Defense Meteorological Satellite Program/Operational Linescan System, DMSP/OLS) and land-use data.

From Metaphor to Measurement: Resilience of What to What?

Journal Articles & Books
Décembre, 2001

Resilience is the magnitude of disturbance that can be tolerated before a socioecological system (SES) moves to a different region of state space controlled by a different set of processes. Resilience has multiple levels of meaning: as a metaphor related to sustainability, as a property of dynamic models, and as a measurable quantity that can be assessed in field studies of SES. The operational indicators of resilience have, however, received little attention in the literature.

Flood regulating ecosystem services—Mapping supply and demand, in the Etropole municipality, Bulgaria

Journal Articles & Books
Décembre, 2012
Bulgarie

Floods exert significant pressure on human societies. Assessments of an ecosystem's capacity to regulate and to prevent floods relative to human demands for flood regulating ecosystem services can provide important information for environmental management. In this study, the capacities of different ecosystems to regulate floods were assessed through investigations of water retention functions of the vegetation and soil cover.

Forest fire risk assessment in parts of Northeast India using geospatial tools

Journal Articles & Books
Décembre, 2011
Inde

Forest fire is a major cause of changes in forest structure and function. Among various floristic regions, the northeast region of India suffers maximum from the fires due to age-old practice of shifting cultivation and spread of fires from jhum fields. For proper mitigation and management, an early warning of forest fires through risk modeling is required. The study results demonstrate the potential use of remote sensing and Geographic Information System (GIS) in identifying forest fire prone areas in Manipur, southeastern part of Northeast India.

Land use and land cover variation and soil properties of Cankırı-Eldivan Karataşbağı river basin

Policy Papers & Briefs
Décembre, 2007
Turquie

The main objective of this study was to investigate changing of land uses and land covers and to compare current conditions of the basin with project results that were performed in 1961-2006 and to determine some soil properties of the basin. Stand relating to 1995 and 2006, geological and topographical maps and climatic data were used in this study. According to results, while forest area covered 14.5 % of the total area in 1955 was increased (35.8 %), degraded coppice, degraded blackpine and agricultural lands were decreased 5.7, 1.8 and 15.8% respectively.

Carbon management of commercial rangelands in Australia: Major pools and fluxes

Journal Articles & Books
Décembre, 2012
Australie

Land-use emissions accompanying biomass loss, change in soil organic carbon (ΔSOC) and decomposing wood-products, were comparable with fossil fuel emissions in the late 20th century. We examine the rates, magnitudes and uncertainties for major carbon (C) fluxes for rangelands due to commercial grazing and climate change in Australia. Total net C emission from biomass over 369Mha of rangeland to-date was 0.73 (±0.40)Pg, with 83% of that from the potentially forested 53% of the rangelands. A higher emission estimate is likely from a higher resolution analysis.

Legacy Effects of Different Land-Use Histories Interact with Current Grazing Patterns to Determine Grazing Lawn Soil Properties

Journal Articles & Books
Décembre, 2015

Pastoralism and agriculture have affected rangeland ecosystems over the past millennia, including many ecosystems that are currently protected as reserves. However, the legacy of these land-use practices on current ecosystem functioning remains unclear. We studied legacy effects of former human land use on soil physical and chemical properties in a South African savanna.

Combining solar photovoltaic panels and food crops for optimising land use: Towards new agrivoltaic schemes

Journal Articles & Books
Décembre, 2011

The need for new sources of renewable energies and the rising price of fossil fuels have induced the hope that agricultural crops may be a source of renewable energy for the future. We question in this paper the best strategies to convert solar radiation into both energy and food. The intrinsic efficiency of the photosynthetic process is quite low (around 3%) while commercially available monocristalline solar photovoltaic (PV) panels have an average yield of 15%. Therefore huge arrays of solar panels are now envisaged.

Comparison of the USGS 2001 NLCD to the 2002 USDA Census of Agriculture for the Upper Midwest United States

Journal Articles & Books
Décembre, 2008
États-Unis d'Amérique

The U.S. Geological Survey (USGS) 2001 National Land Cover Database (NLCD) was compared to the U.S. Department of Agriculture (USDA) 2002 Census of Agriculture. We compared areal estimates for cropland at the state and county level for 14 States in the Upper Midwest region of the United States. Absolute differences between the NLCD and Census cropland areal estimates at the state level ranged from 1.3% (Minnesota) to 37.0% (Wisconsin). The majority of counties (74.5%) had differences of less than 100km². 7.2% of the counties had differences of more than 200km².