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Identification of Potential Sites for Groundwater Recharge Using a GIS-Based Decision Support System in Jazan Region-Saudi Arabia

Journal Articles & Books
Décembre, 2014

In arid and semi-arid environments, the amount of recharge received by aquifers is far more critical to the sustainable use of water than it is in humid regions. Groundwater recharge (GWR) is critical to maintain the abundance of groundwater. In the present study, suitable areas for GWR in Jazan region have been identified by using a GIS-based decision support system (DSS). The DSS was implemented to obtain suitability maps and to evaluate the existing GWR in the study area.

Evaluating the Impact of Distance Measures on Deforestation Simulations in the Fluvial Landscapes of Amazonia

Journal Articles & Books
Décembre, 2014

Land use and land cover change (LUCC) models frequently employ different accessibility measures as a proxy for human influence on land change processes. Here, we simulate deforestation in Peruvian Amazonia and evaluate different accessibility measures as LUCC model inputs. We demonstrate how the selection, and different combinations, of accessibility measures impact simulation results. Out of the individual measures, time distance to market center catches the essential aspects of accessibility in our study area.

Effects of the large-scale atmospheric circulation on the onset and strength of urban heat islands: a case study

Journal Articles & Books
Décembre, 2014

Air temperature was monitored at 13 sites across the urban perimeter of a Brazilian midsize city in winter 2011. In this study, we show that the urban heat island (UHI) develops only at night and under certain weather conditions, and its intensity depends not only on the site's land cover but also on the meteorological setting. The urban heat island intensity was largest (6.6� °C) under lingering high-pressure conditions, milder (3.0� °C) under cold anticyclones and almost vanished (1.0� °C) during the passage of cold fronts.

new index for mapping built-up and bare land areas from Landsat-8 OLI data

Journal Articles & Books
Décembre, 2014
Chine

Remote sensing is a useful technology for monitoring the spatial distribution and expansion of built-up and bare land areas. One effective approach, known as the normalized difference built-up index (NDBI), has been promoted for identifying built-up areas based on Landsat Thematic Mapper (TM)/Enhanced Thematic Mapper (ETM+) data.

Predicting climate change effects on surface soil organic carbon of Louisiana, USA

Journal Articles & Books
Décembre, 2014
États-Unis d'Amérique

This study aimed to assess the degree of potential temperature and precipitation change as predicted by the HadCM3 (Hadley Centre Coupled Model, version 3) climate model for Louisiana, and to investigate the effects of potential climate change on surface soil organic carbon (SOC) across Louisiana using the Rothamsted Carbon Model (RothC) and GIS techniques at the watershed scale.

Framework to Predict the Impacts of Shale Gas Infrastructures on the Forest Fragmentation of an Agroforest Region

Journal Articles & Books
Décembre, 2014
Canada
États-Unis d'Amérique

We propose a framework to facilitate the evaluation of the impacts of shale gas infrastructures (well pads, roads, and pipelines) on land cover features, especially with regards to forest fragmentation. We used a geographic information system and realistic development scenarios largely inspired by the PA (United States) experience, but adapted to a region of QC (Canada) with an already fragmented forest cover and a high gas potential.

Importance of closed landfills as green space in urbanized areas: ecological assessment using carabid beetles

Journal Articles & Books
Décembre, 2014

In a closed landfill, we investigated the diversity and ecological characters of carabid beetles to understand the ecological importance of closed landfills that have the potential as a multi-functional habitat for improving biodiversity in urbanized areas. In addition, we studied the influence of environmental factors (vegetation structure, soil) on distribution and diversity of carabid beetles. A total of 92,495 individuals representing 15 carabid species were collected from the closed landfill.

Quantification des Changements Récents à 'Écotone forêt-Toundra à Partir de 'Analyse Numérique de Photographies Aériennes

Journal Articles & Books
Décembre, 2014
Canada

Arctic ecosystems at the forest-tundra ecotone are particularly sensitive to climate-driven vegetation changes. Many recent studies have observed shifts in vegetation cover, particularly an increase in shrub growth. Here, vegetation changes were assessed at the local scale near Umiujaq, northern Quebec (Canada, 56.55°N, 76.55°W) using colour aerial photographs (1994 and 2010). By applying semi-automated image classification methods and change-detection analysis, we were able to detect and map the dominant vegetation cover changes.

Assessing the influence of geography, land cover and host species on the local abundance of a generalist brood parasite, the brown‐headed cowbird

Journal Articles & Books
Décembre, 2014
États-Unis d'Amérique

AIM: The brown‐headed cowbird is an obligate brood parasite known to exploit a large number of host species and use a variety of habitats. Much attention has been directed towards uncovering the fundamental factors that affect cowbird abundance; however, no study has evaluated these factors in the context of a biogeographic‐scale analysis that takes into account spatial autocorrelation. Our primary objective was to compare the relative influence of geography, land cover and host species on the local abundance of cowbirds. LOCATION: Great Plains region of the USA.

Suitable, reachable but not colonised: seasonal niche duality in an endemic mountainous songbird

Journal Articles & Books
Décembre, 2014

The realized distribution of animals is often delimited by climatic factors which define, next to the specific habitat and food availability, their species-specific potential distribution. We studied the environmental limitations affecting the realized breeding and wintering distributions of the Citril Finch (Carduelis citrinella), one of the few endemic bird species of European mountain ranges. To assess the environmental limits that shape the seasonal distribution, we used species distribution models (SDMs) derived from macroclimate in combination with land cover information.

Modeling the Landscape Drivers of Fire Recurrence in Sardinia (Italy)

Journal Articles & Books
Décembre, 2014
Italie

Although recurrent fire events with very short return periods have the most dangerous effects on landscape degradation, only a few papers have explored the landscape ecological factors that drive the probability of fire recurrence. In this paper we apply a habitat suitability model for analyzing the spatial relationship between a selected set of landscape factors (mainly land use types) and fire recurrence in Sardinia (Italy) in the years 2005–2010.

Assessment of some remote sensing techniques used to detect land use/land cover changes in South-East Transilvania, Romania

Journal Articles & Books
Décembre, 2014
Roumanie

This paper assesses the image differencing technique for the Normalized Difference Vegetation Index (NDVI), the second principal component (PC2), and the TM 4 band (TM 4), as well as the post-classification comparison (PCC) in order to analyze the land use/land cover changes in the South-East Transilvania, Romania. The analysis was performed using two frames from Landsat 5 TM satellite images acquired on August 5, 1993 and July 24, 2009. After applying the NDVI, PC2, and TM 4 image differencing techniques, the images obtained were transformed into change/no change maps.