Aller au contenu principal

page search

Issuesutilisation des terresLandLibrary Resource
There are 9, 801 content items of different types and languages related to utilisation des terres on the Land Portal.
Displaying 1837 - 1848 of 4598

Assessment of the MODIS global evapotranspiration algorithm using eddy covariance measurements and hydrological modelling in the Rio Grande basin

Journal Articles & Books
Décembre, 2013
Brésil
Global

Remote sensing is considered the most effective tool for estimating evapotranspiration (ET) over large spatial scales. Global terrestrial ET estimates over vegetated land surfaces are now operationally produced at 1-km spatial resolution using data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the MOD16 algorithm. To evaluate the accuracy of this product, ground-based measurements of energy fluxes obtained from eddy covariance sites installed in tropical biomes and from a hydrological model (MGB-IPH) were used to validate MOD16 products at local and regional scales.

Environmental Cognitions, Land Change and Social-Ecological Feedbacks: Local Case Studies of Forest Transition in Vietnam

Journal Articles & Books
Décembre, 2013
Viet Nam

Forest transition — i.e., the shift from decreasing to expanding forest cover — in the northern mountains of Vietnam was analyzed at the local scale in four villages from the 1970s to 2007–2008 to understand feedbacks from local environmental degradation on land uses, the conditions under which such feedbacks occur, and their possible roles in the transition. Remote sensing data were combined with field surveys including interviews, group discussions, mental and participatory mapping, observations and secondary sources.

Retaining Open Space with Purchasable Development Rights Programs

Journal Articles & Books
Décembre, 2003

This paper examines the preservation of farmland through purchasable development rights. In a comparison of the estimated costs and benefits associated with the development of open space from 1982 to 1992, we show that these programs may provide a net benefit to society. An econometric model is employed to address the question of what factors explain both the creation of these programs and the magnitude of farmland preservation.

Landscape fragmentation, land-use legacy and propagule pressure promote plant invasion on coastal dunes: a patch-based approach

Journal Articles & Books
Décembre, 2014
Europe

Coastal dunes and sand areas are reported to be among the habitats most invaded by alien species in Europe. Landscape pattern could be a significant driver in invasion processes in parallel with land-use legacy. Fragmentation of natural habitats combined with the availability of propagules from the surrounding matrix may enhance the invisibility of ecological communities.

critical re-evaluation of controls on spatial and seasonal variations in nitrate concentrations in river waters throughout the River Derwent catchment in North Yorkshire, UK

Journal Articles & Books
Décembre, 2016

Since mean nitrate concentration along single river channels increases significantly with percent arable land use upstream of sampling points and autumn/early winter flushes in nitrate concentration are widespread, it is generally concluded that farmers contribute most of the nitrate. For the River Derwent in North Yorkshire, the correlation between nitrate concentration and percent arable land use is much poorer when tributary data are included in the equation, because of greater variations in dilution by water draining upland areas and in other N input sources.

Large herbivore responses to surface water and land use in an East African savanna: implications for conservation and human-wildlife conflicts

Journal Articles & Books
Décembre, 2014
Kenya

Water, forage and predation constrain ungulate distributions in savannas. To understand these constraints, we characterized distributions of 15 herbivore species from water, locations of peak density and degree of clustering around the peaks using zero-inflated count data models and mapping census data collected in the Mara reserve and the adjoining pastoral ranches in Kenya during a wet and dry year.

Irrigated land retirement

Journal Articles & Books
Décembre, 2002

Land retirement is ceasing irrigation with the goal of reducing load, in general, of dissolved constituents and, in particular, of trace elements, present in subsurface drainage generated from irrigated lands. Retirement is achieved through a process of goal setting, strategy development and determining effects, developing land selection criteria, implementation, and monitoring. In this study, effects of land retirement are evaluated using hydrologic,soil and economic models as well as results from a field demonstration study.

Understanding species persistence for defining conservation actions: A management landscape for jaguars in the Atlantic Forest

Journal Articles & Books
Décembre, 2013
Amérique du Sud

Habitat models constitute useful instruments for understanding species-habitat interactions and can constitute helpful conservation tools. The Upper Paraná Atlantic Forest (UPAF) of South America still holds the world’s southernmost jaguar (Panthera onca) population.

Simple models of carbon and nitrogen cycling in New Zealand hill country pastures: exploring impacts of intensification on soil C and N pools

Journal Articles & Books
Décembre, 2011
Nouvelle-Zélande

Concerns about climate change and water quality make it necessary to have a better understanding of the cycling of carbon (C) and nitrogen (N) within landscapes. In New Zealand, pastoral farming on hill country is a major land use, and there is little information available at a landscape level on the cycling of C and N within these systems, particularly the impacts of land use intensification.

Hierarchical mapping of Northern Eurasian land cover using MODIS data

Journal Articles & Books
Décembre, 2011

The Northern Eurasian land mass encompasses a diverse array of land cover types including tundra, boreal forest, wetlands, semi-arid steppe, and agricultural land use. Despite the well-established importance of Northern Eurasia in the global carbon and climate system, the distribution and properties of land cover in this region are not well characterized. To address this knowledge and data gap, a hierarchical mapping approach was developed that encompasses the study area for the Northern Eurasia Earth System Partnership Initiative (NEESPI).

Uso de las tierras, fisiografía y degradación, en el noreste del departamento Aluminé, Neuquén

Journal Articles & Books
Décembre, 2009

Kilca River basin is one of the major river systems before the mountain region, located in the center of the province of Neuquen. In this zone, humid climates, the dominant land use is "veranada", which consists of three annual steps of one type of livestock transhumance, based on the exploitation of natural grassland forage. Given the physiographic formation of these landscapes, there is in them a high propensity to develop geomorphological processes of erosion and landslides.