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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 1825 - 1836 of 4598

Effect of changing groundwater levels caused by land-use changes on greenhouse gas fluxes from tropical peat lands

Journal Articles & Books
Décembre, 2005
Indonésie
Global

Monthly measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes in peat soils were carried out and compared with groundwater level over a year at four sites (drained forest, upland cassava,upland and lowland paddy fields) located in Jambi province, Indonesia. Fluxes from swamp forest soils were also measured once per year as the native state of this investigated area.

Indicators for spatial–temporal comparisons of ecosystem service status between regions: A case study of the Taihu River Basin, China

Journal Articles & Books
Décembre, 2016
Chine

With the development of ecological science, the demand to integrate ecosystem services into ecological management is increasing. Stakeholders are interested in comparing stocks and ability to supply ecosystem services in different regions. However, different areas may have different primary ecosystem services and knowledge of the aggregated value of ecosystem services may be lacking, making comparisons difficult. Relevant indicators that can integrate a group of ecosystem services for comparison are therefore needed.

Land use and climate changes and their impacts on runoff in the yarlung zangbo river basin, china

Journal Articles & Books
Décembre, 2014
Chine

Impacts of land use and climate change on runoff were investigated by studying the runoff in the Yarlung Zangbo River basin, China. Trends in precipitation, mean air temperature, and runoff were analysed by non‐parametric Mann‐Kendall tests. Land‐use changes were examined with land‐use transition matrix and geographic information system tools. Land‐use and climate changes showed several characteristics, including increased reforestation, decreased grassland, retreat of glaciers and increased desertification.

Site-scale isotopic variations along a river course help localize drainage basin influence on river food webs

Journal Articles & Books
Décembre, 2016

In human-impacted rivers, nutrient pollution has the potential to disrupt biodiversity organisation and ecosystem functioning, prompting calls for effective monitoring and management. Pollutants, together with natural variations, can modify the isotopic signature of aquatic organisms. Accordingly, we explored the potential of isotopic variations as an indicator of drainage basin influences on river food webs. We assessed stable N and C isotopes within six food webs along a river affected by multiple pollution sources.

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.

Land change variability and human–environment dynamics in the United States Great Plains

Journal Articles & Books
Décembre, 2012
États-Unis d'Amérique

Land use and land cover changes have complex linkages to climate variability and change, biophysical resources, and socioeconomic driving forces. To assess these land change dynamics and their causes in the Great Plains, we compare and contrast contemporary changes across 16 ecoregions using Landsat satellite data and statistical analysis. Large-area change analysis of agricultural regions is often hampered by change detection error and the tendency for land conversions to occur at the local-scale.

Ecohydrological feedback mechanisms in arid rangelands: Simulating the impacts of topography and land use

Journal Articles & Books
Décembre, 2009

The interaction between ecological and hydrological processes is particularly important in arid and semi-arid regions. Often the interaction between these processes is not completely understood and they are studied separately. We developed a grid-based computer model simulating the dynamics of the four most common vegetation types (perennial grass, annuals, dwarf shrubs and shrubs) and related hydrological processes in the region studied.

Application of Tabu Search Algorithm With a Coupled AnnAGNPS-CCHE1D Model to Optimize Agricultural Land Use

Journal Articles & Books
Décembre, 2008

Abstract: A principal contributor to soil erosion and nonpoint source pollution, agricultural activities have a major influence on the environmental quality of a watershed. Impact of agricultural activities on the quality of water resources can be minimized by implementing suitable agriculture land-use types. Currently, land uses are designed (location, type, and operational schedule) based on field study results, and do not involve a science-based approach to ensure their efficiency under particular regional, climatic, geological, and economical conditions.