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Mapping attributes of Canada’s forests at moderate resolution through kNN and MODIS imagery

Journal Articles & Books
Décembre, 2014
Canada

Canada’s National Forest Inventory (NFI) sampling program is designed to support reporting on forests at the national scale. On the other hand, continuous maps of forest attributes are required to support strategic analyses of regional policy and management issues. We have therefore produced maps covering 4.03 × 10⁶ km² of inventoried forest area for the 2001 base year using standardised observations from the NFI photo plots (PP) as reference data.

Landscape dynamic characteristics using satellite data for a mountainous watershed of Abha, Kingdom of Saudi Arabia

Journal Articles & Books
Décembre, 2014
Arabie saoudite

The changes in land use/land cover (LULC) play a major role in the study of various aspects of environmental issues. Land use is the results of various socioeconomic activities taking place at various urban and regional setups. In this paper, landscape dynamic characteristics are investigated by using remote sensing and geographic information system in mountainous watershed of Abha, Saudi Arabia. Land use classes were mapped and assessed from a time series of maps of year 2000–2010. The LULC transformations were also analyzed according to elevation and slope.

Land‐use change: incorporating the frequency, sequence, time span, and magnitude of changes into ecological research

Journal Articles & Books
Décembre, 2014

The frequency and extent of human‐induced land‐cover changes is escalating worldwide. Recurrent turnover of land‐cover types will affect ecosystems over and above major, one‐time changes (eg deforestation). Here, we show how a deeper appreciation of the temporal dynamics of land‐cover change is needed to understand its effects on ecosystems.

Spatial variation of trace elements in the peri-urban soil of Madrid

Journal Articles & Books
Décembre, 2014

PURPOSE: The peri-urban region to the south east of Madrid contains a mixture of housing, manufacturing industry and farming, some of which disperse metals, in particular cadmium, copper, lead, and zinc, into the soil. We have mapped the concentrations of these elements and identified the major influences on their distributions. MATERIAL AND METHODS: We sampled the topsoil at 125 sites across 1,050� km² of peri-urban land to the south east of the city on two grids, one nested inside the other. At each site, we measured the current contents of the four trace elements in the soil.

Effects of topography on status and changes in land-cover patterns, Chongqing City, China

Journal Articles & Books
Décembre, 2014
Chine

Chongqing Municipality, located on the upper reaches of the Yangtze River, is one of China’s four largest megacities, comparable with Shanghai, Beijing, and Tianjin. In recent years, Chongqing and its surroundings have been experiencing severe environmental problems, such as urbanization, pollution, and deforestation, due to the rapid economic development of China’s inland region.

integrated methodology to assess future water resources under land use and climate change: an application to the Tahadart drainage basin (Morocco)

Journal Articles & Books
Décembre, 2014
Maroc

The assessment of freshwater resources in a drainage basin is not only dependent on its hydrologic parameters but also on the socio-economic system driving development in the watershed area; the socio-economic aspect, that is often neglected in hydrologic studies, is one of the novelties of this study. The aim of this paper is twofold: (1) presenting an integrated working methodology and (2) studying a local case of a North African watershed where scarce field data are available.

Relationships Between Land Cover and Dissolved Organic Matter Change Along the River to Lake Transition

Journal Articles & Books
Décembre, 2014

Dissolved organic matter (DOM) influences the physical, chemical, and biological properties of aquatic ecosystems. We hypothesized that controls over spatial variation in DOM quantity and composition (measured with DOM optical properties) differ based on the source of DOM to aquatic ecosystems. DOM quantity and composition should be better predicted by land cover in aquatic habitats with allochthonous DOM and related more strongly to nutrients in aquatic habitats with autochthonous DOM.

Assessment of uncertainties in the response of the African monsoon precipitation to land use change simulated by a regional model

Journal Articles & Books
Décembre, 2014
Afrique

Land use and land cover (LULC) over Africa have changed substantially over the last 60 years and this change has been proposed to affect monsoon circulation and precipitation. This study examines the uncertainties of model simulated response in the African monsoon system and Sahel precipitation due to LULC change using a set of regional model simulations with different combinations of land surface and cumulus parameterization schemes.

Impacts of landscape fragmentation on simulated precipitation fields in the Amazonian sub-basin of Ji-Paraná using the Eta model

Journal Articles & Books
Décembre, 2014

Numerical studies on impacts of landscape fragmentation due to land use and land cover change (LUCC) on precipitation fields over the Ji-Paraná basin in the Amazon region are carried out using atmospheric Eta model. Experiments consider historical data about LUCC over the basin from 1978 to 2000 and compare simulations under LUCC conditions with simulations under pristine conditions. In agreement with previous observational studies, model results do not show statistically significant impacts on precipitation in the region.

Closing the gap between plant ecology and Quaternary palaeoecology

Journal Articles & Books
Décembre, 2014

Ecology and Quaternary palaeoecology have largely developed as parallel disciplines. Although both pursue related questions, information exchange is often hampered by particularities of the palaeoecological data and a communication gap has been perceived between the disciplines. Based on selected topics and developments mainly in Quaternary palaeoecology, we show that both disciplines have converged somewhat during recent years, while we still see untapped potential for closer interactions.

Morphometry and land cover based multi-criteria analysis for assessing the soil erosion susceptibility of the western Himalayan watershed

Journal Articles & Books
Décembre, 2014

Complex mountainous environments such as Himalayas are highly susceptibility to natural hazards particular those that are triggered by the action of water such as floods, soil erosion, mass movements and siltation of the hydro-electric power dams. Among all the natural hazards, soil erosion is the most implicit and the devastating hazard affecting the life and property of the millions of people living in these regions.