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Assessment of forest disturbances by selective logging and forest fires in the Brazilian Amazon using Landsat data

Journal Articles & Books
Décembre, 2013

The rapid environmental changes occurring in the Brazilian Amazon due to widespread deforestation have attracted the attention of the scientific community for several decades. A topic of particular interest involves the assessment of the combined impacts of selective logging and forest fires. Forest disturbances by selective logging and forest fires may vary in scale, from local to global changes, mostly related to the increase of carbon dioxide released into the atmosphere.

Uncertainty in hydromorphological and ecological modelling of lowland river floodplains resulting from land cover classification errors

Journal Articles & Books
Décembre, 2013
Pays-Bas

Land cover maps provide essential input data for various hydromorphological and ecological models, but the effect of land cover classification errors on these models has not been quantified systematically. This paper presents the uncertainty in hydromorphological and ecological model output for a large lowland river depending on the classification accuracy (CA) of a land cover map.

Modelling catchment hydrological responses in a Himalayan Lake as a function of changing land use and land cover

Journal Articles & Books
Décembre, 2013

In this paper, we evaluate the impact of changing land use/land cover (LULC) on the hydrological processes in Dal lake catchment of Kashmir Himalayas by integrating remote sensing, simulation modelling and extensive field observations. Over the years, various anthropogenic pressures in the lake catchment have significantly altered the land system, impairing, inter-alia, sustained biotic communities and water quality of the lake.

approach for characterizing the distribution of shrubland ecosystem components as continuous fields as part of NLCD

Journal Articles & Books
Décembre, 2013
États-Unis d'Amérique

Characterizing and quantifying distributions of shrubland ecosystem components is one of the major challenges for monitoring shrubland vegetation cover change across the United States. A new approach has been developed to quantify shrubland components as fractional products within National Land Cover Database (NLCD). This approach uses remote sensing data and regression tree models to estimate the fractional cover of shrubland ecosystem components.

Drought vulnerability drives land-use and land cover changes in the Rift Valley dry lands of Ethiopia

Journal Articles & Books
Décembre, 2013
Éthiopie

The Ethiopian Rift Valley is a dry land zone where for a long time pastoral communities have made their living from acacia-based woodlands. But many pastoralists have changed from a pastoral way of life to mixed farming over time. The aim of this study was to evaluate land-use and land cover (LULC) changes in the Central Rift Valley dry lands of Ethiopia, and determine the role of drought vulnerability as a driver. A combination of GIS/remote sensing techniques, drought vulnerability analyses, field observation and surveying were employed.

Potential ecological distribution of Cytauxzoon felis in domestic cats in Oklahoma, Missouri, and Arkansas

Journal Articles & Books
Décembre, 2013

The ecological distribution of Cytauxzoon felis, an often-fatal tick-borne apicomplexan that infects domestic cats, has not been evaluated or identified despite its continued emergence. Infection of C. felis is characterized by lethargy, icterus, fever, anorexia, anemia, and death. The natural vertebrate reservoir of C. felis is the bobcat (Lynx rufus). To determine the possible distribution of C. felis in three states where infection is common (Oklahoma, Missouri, and Arkansas), two separate approaches to ecological niche modeling were implemented.

Climatic and land cover influences on the spatiotemporal dynamics of Holocene boreal fire regimes

Journal Articles & Books
Décembre, 2013
États-Unis d'Amérique

Although recent climatic warming has markedly increased fire activity in many biomes, this trend is spatially heterogeneous. Understanding the patterns and controls of this heterogeneity is important for anticipating future fire regime shifts at regional scales and for developing land management policies. To assess climatic and land cover controls on boreal forest fire regimes, we conducted macroscopic‐charcoal analysis of sediment cores and GIS analysis of landscape variation in south‐central Alaska, USA.

Recent decadal growth of the Atchafalaya River Delta complex: Effects of variable riverine sediment input and vegetation succession

Journal Articles & Books
Décembre, 2013

The Mississippi River Delta Plain has experienced substantial wetland loss from subsidence, erosion, and sea level rise, threatening coastal communities and the ecosystems that support them. The Atchafalaya River, the largest distributary of the Mississippi River, has one of the few prograding delta features along the ~200-km deltaic coastline. Understanding changes in the Atchafalaya River Delta complex (ARDC) development has critical implications for future prediction and management strategy for the Mississippi River Delta Plain.

Sensitivity of spectral reflectance values to different burn and vegetation ratios: A multi-scale approach applied in a fire affected area

Journal Articles & Books
Décembre, 2013
Grèce

The aim of our study was to explore the spectral properties of fire-scorched (burned) and non fire-scorched (vegetation) areas, as well as areas with different burn/vegetation ratios, using a multisource multiresolution satellite data set. A case study was undertaken following a very destructive wildfire that occurred in Parnitha, Greece, July 2007, for which we acquired satellite images from LANDSAT, ASTER, and IKONOS. Additionally, we created spatially degraded satellite data over a range of coarser resolutions using resampling techniques.

hierarchical patch mosaic ecosystem model for urban landscapes: Model development and evaluation

Journal Articles & Books
Décembre, 2013

Urbanization effects on ecosystem functions are both important and complex, characterized by scale multiplicity, spatial heterogeneity, and intensive human disturbances. Integrating the hierarchical structure of urban landscape pattern with ecosystem processes through simulation modeling can facilitate our understanding of human–environment interactions in urban environment.

Estimation and comparision of curve numbers based on dynamic land use land cover change, observed rainfall-runoff data and land slope

Journal Articles & Books
Décembre, 2013

The CN represents runoff potential is estimated using three different methods for three watersheds namely Barureva, Sher and Umar watershed located in Narmada basin. Among three watersheds, Sher watershed has gauging site for the runoff measurements. The CN computed from the observed rainfall-runoff events is termed as CN₍PQ₎, land use and land cover (LULC) is termed as CN₍LU₎ and the CN based on land slope is termed as SACN₂. The estimated annual CN₍PQ₎ varies from 69 to 87 over the 26years data period with median 74 and average 75.

Validating the BERMS in situ Soil Water Content Data Record with a Large Scale Temporary Network

Journal Articles & Books
Décembre, 2013

Calibration and validation of soil moisture satellite products requires data records of large spatial and temporal extent and for diverse land cover types. Obtaining this data, especially for forests, can be challenging. These challenges can include the remoteness of the locations, and expense of equipment. A location with a long record of soil water content data and the potential provide this important data is the Boreal Ecosystem Research and Monitoring Sites (BERMS) in Saskatchewan Canada. In and around the BERMS study area, there are five long-term soil water content profile stations.