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Vegetation change in Brazil’s dryland ecoregions and the relationship to crop production and environmental factors: Cerrado, Caatinga, and Mato Grosso, 2001–2009

Journal Articles & Books
Diciembre, 2013
Brasil

South America’s drylands remain some of the most threatened ecosystems on the planet. Yet, we know very little about the dynamics of land-use and land-cover change (LUCC) in these understudied regions. Our objective is to map vegetation change in Brazil’s three largest dryland ecoregions – the Cerrado, Caatinga, and Mato Grosso seasonal forests – using MODIS (Moderate Resolution Imaging Spectroradiometer) data from 2001 to 2009 at the scale of the municipality.

Assessing the spatio-temporal rates and patterns of land-use and land-cover changes in the Cerrados of southeastern Mato Grosso, Brazil

Journal Articles & Books
Diciembre, 2013
Brasil

The Cerrados of central Brazil have undergone profound landscape transformation in recent decades due to agricultural expansion, and this remains poorly assessed. The present research investigates the spatial-temporal rates and patterns of land-use and land-cover (LULC) changes in one of the main areas of agricultural production in Mato Grosso State (Brazil), the region of Primavera do Leste. To quantify the different aspects of LULC changes (e.g.

Patterns of forest vegetation responses to edge effect as revealed by a continuous approach

Journal Articles & Books
Diciembre, 2013
Francia

CONTEXT : Understanding the variability of vegetation distribution and its determinants is a central issue for addressing the effects of edges on ecological processes. Recent studies have revealed inconsistencies in the patterns of responses to edge effects that raise important questions about their determinants. We investigated the edge effect response patterns by adapting a recently proposed continuous approach to the case of small forest fragments in southwestern France.

Identifying potential areas of Cannabis sativa plantations using object-based image analysis of SPOT-5 satellite data

Journal Articles & Books
Diciembre, 2013
Brasil

The rapid and efficient detection of illicit drug cultivation, such as that of Cannabis sativa, is important in reducing consumption. The objective of this study was to identify potential sites of illicit C. sativa plantations located in the semi-arid, southern part of Pernambuco State, Brazil. The study was conducted using an object-based image analysis (OBIA) of Système Pour l'Observation de la Terre high-resolution geometric (SPOT-5 HRG) images (overpass: 31 May, 2007).

Use of fraction imagery, segmentation and masking techniques to classify land-use and land-cover types in the Brazilian Amazon

Journal Articles & Books
Diciembre, 2013

This work presents a procedure for classifying land-use and land-cover (LULC) types in the Brazilian Amazon. Fraction imagery representing proportions of green vegetation, soil, and shade was estimated using all six reflective bands of the Landsat-5 Thematic Mapper (TM1 to TM5 and TM7) through the linear spectral mixing model (LSMM).

Density fractionation and ¹³C reveal changes in soil carbon following woody encroachment in a desert ecosystem

Journal Articles & Books
Diciembre, 2013

Woody encroachment has dramatically changed land cover patterns in arid and semiarid systems (drylands) worldwide over the past 150 years. This change is known to influence bulk soil carbon (C) pools, but the implications for dynamics and stability of these pools are not well understood.

Interpolation-based super-resolution land cover mapping

Journal Articles & Books
Diciembre, 2013

Super-resolution mapping (SRM) is a technique to produce a land cover map with finer spatial resolution by using fractional proportion images as input. A two-step SRM approach has been widely used. First, a fine-resolution indicator map is estimated for each class from the coarse-resolution fractional image. All indicator maps are then combined to create the final fine-resolution land cover map.

Habitat suitability modelling for Gaur (Bos gaurus) using multiple logistic regression, remote sensing and GIS

Journal Articles & Books
Diciembre, 2013
India

The aim of this study is to produce georeferenced ecological information about the suitable habitats available for gaur Bos gaurus in Chandoli tiger reserve, India (17° 04′ 00″ N to 17° 19′ 54″ N and 73° 40′ 43″ E to 73° 53′ 09″ E). Habitat suitability index (H.S.I.) was developed using multiple logistic regression (MLR) integrated with remote sensing (RS) and geographic information system (GIS).

Species Distribution Models of Freshwater Stream Fishes in Maryland and Their Implications for Management

Journal Articles & Books
Diciembre, 2013
Estados Unidos de América

Species distribution models (SDMs) are often used in conservation planning, but their utility can be improved by assessing the relationships between environmental and species response variables. We constructed SDMs for 30 stream fishes of Maryland, USA, using watershed attributes as environmental variables and presence/absence as species responses. SDMs showed substantial agreement between observed and predicted values for 17 species.

Spatial patterns of soil moisture under forest and grass land cover in a suburban area, in Maryland, USA

Journal Articles & Books
Diciembre, 2013
Estados Unidos de América

Knowledge about the effects of changing environmental factors on stability of spatial structure of soil moisture is important in measurement design and spatial and land-atmosphere modeling, but was rarely considered. We examined the effects of soil temperature and moisture on spatial structure of daily soil moisture at 10-cm and 20-cm depth covering forest and grass sampling points (31 and 11, respectively) over 10months with a maximum between-point distance of 130m.

Trans-boundary infrastructure and land cover change: Highway paving and community-level deforestation in a tri-national frontier in the Amazon

Journal Articles & Books
Diciembre, 2013
Bolivia
Brasil
Perú

Economic globalization manifests in landscapes through regional integration initiatives involving trans-boundary infrastructure. While the relationships of roads, accessibility and land cover are well-understood, they have rarely been considered across borders in national frontier regions. We therefore pursue an analysis of infrastructure connectivity and land cover change in the tri-national frontier of the southwestern Amazon where Bolivia, Brazil and Peru meet, and where the Inter-Oceanic Highway has recently been paved.

tool for simulation and geo-animation of wildfires with fuel editing and hotspot monitoring capabilities

Journal Articles & Books
Diciembre, 2013
Europa

FLogA (Fire Logic Animation) is a set of methods and an interactive, Web-based, user-friendly software tool which allows the user to draw a forest area on the map anywhere in Europe, insert fire ignition points, generate on the fly all input data layers required for a wildfire simulation, and then simulate and animate the behavior of the evolving fireline under different weather conditions. FLogA utilizes only publicly available non-proprietary data, software libraries and Web services. It adopts a distributed, open, service oriented architecture that is easy to maintain and extend.