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Representing ecological processes in agent-based models of land use and cover change
Agent-based models of land use and cover change (ABMs/LUCC) have traditionally represented land-use and land-cover changes as arising from social, economic and demographic conditions, while spatial ecological models have tended to simulate the environmental impacts of spatially aggregated human decisions.
Impact of Topography on Accuracy of Land Cover Spectral Change Vector Analysis Using AWiFS in Western Himalaya
The present paper discusses the impact of topography on accuracy for land cover classification and “from-to class change using improved spectral change vector analysis suggested by Chen et al. (2003). Two AWiFS sensor images of different dates are used. Double Window Flexible Pace Search (DFPS) is used to estimate threshold of change magnitude for change/no change classes. The topographic corrections show accuracy of 90% (Kappa coefficient 0.7811) for change/no change area as compared to 82% (Kappa coefficient 0.6512) in uncorrected satellite data.
Using MERIS fused images for land-cover mapping and vegetation status assessment in heterogeneous landscapes
In this paper we evaluate the potential of ENVISAT–Medium Resolution Imaging Spectrometer (MERIS) fused images for land-cover mapping and vegetation status assessment in heterogeneous landscapes. A series of MERIS fused images (15 spectral bands; 25 m pixel size) is created using the linear mixing model and a Landsat Thematic Mapper (TM) image acquired over the Netherlands. First, the fused images are classified to produce a map of the eight main land-cover types of the Netherlands. Subsequently, the maps are validated using the Dutch land-cover/land-use database as a reference.
Vegetation change in Brazil’s dryland ecoregions and the relationship to crop production and environmental factors: Cerrado, Caatinga, and Mato Grosso, 2001–2009
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.
Characterizing changes in urban landscape of Nairobi city, Kenya
Landscapes in urban areas especially in developing countries are under pressure due to increasing population of urban dwellers and un-directed spread of city boundaries. Sound urban environment plays important aesthetic, ecological, cultural, social and engineering roles beneficial to the people. To support better management of vegetated sites, it is necessary to understand the spatial configuration at the landscape scale and changes that have occurred.
Realistic Assessment of the Indicator Potential of Butterflies and Other Charismatic Taxonomic Groups
Charismatic groups of animals and plants often are proposed as sentinels of environmental status and trends. Nevertheless, many claims that a certain taxonomic group can provide more-general information on environmental quality are not evaluated critically. To address several of the many definitions of indicator species, we used butterflies to explore in some detail the attributes that affect implementation of indicators generically.
Meta-analysis for the transfer of economic benefits of ecosystem services provided by wetlands within two watersheds in Quebec, Canada
Climate change will cause major changes in ecosystems. Therefore, it is crucial that climate change policy consider the value of all services that are provided by watershed ecosystems. For this purpose, geospatial data and economic analysis are combined to determine a monetary value for wetland ecosystem goods and services (EGSs) in the watersheds of the Yamaska and Bécancour Rivers (Quebec, Canada). From published studies of wetland economic evaluations, we selected 51 relevant studies from 21 countries and performed a benefit transfer using meta-analysis.
multi-level analysis of the relationship between environmental factors and questing Ixodes ricinus dynamics in Belgium
BACKGROUND: Ticks are the most important pathogen vectors in Europe. They are known to be influenced by environmental factors, but these links are usually studied at specific temporal or spatial scales. Focusing on Ixodes ricinus in Belgium, we attempt to bridge the gap between current “single-sided” studies that focus on temporal or spatial variation only. Here, spatial and temporal patterns of ticks are modelled together. METHODS: A multi-level analysis of the Ixodes ricinus patterns in Belgium was performed.
Land Change in Eastern Mediterranean Wood-Pasture Landscapes: The Case of Deciduous Oak Woodlands in Lesvos (Greece)
In Mediterranean Europe, wood-pasture landscapes with oak woodlands as emblematic ecosystems are undergoing rapid land-use change, which may threaten their legacy as hotspots of biodiversity, ecosystem services, and cultural heritage. The objective of this study was to quantify land cover changes and transitions as well as the dynamics of oak woodland patterns and densities over 50 years in two municipalities at the center and edges of Quercus macrolepis distribution in Northern Lesvos (Greece).
Effect of cutting height on forage production of Brachiaria sp. in the piedmont Plains of Colombia
To determine the effect of cutting height on forage production of the grass species Brachiaria decumbens, Brachiaria humidicola, Brachiaria dictyoneura, and Brachiaria brizantha this experiment was carried out at Corpoica’s La Libertad Research Center (Villavicencio, Colombia), under typical conditions found in the piedmont region heights were evaluated 0, 5, 10 and 20 cm in pastures B. decumbens, B. humidicola, B. dityoneura cv. Llanero and 0, 10, 20 and 30 cm for B. brizantha cv. Toledo. The evaluations were conducted during the rainy and dry seasons of 2009 and 2010.
Optimal conservation investment for a biodiversity‐rich agricultural landscape
This study develops a theoretical and empirical framework for optimal conservation planning using satellite land cover data and economic data from a farm survey. A case study is presented for a region within the South‐west Australia Biodiversity Hotspot (Nature 403, 853). This Biodiversity Hotspot is a focus for conservation investment as it combines a relatively high level of biodiversity with severe threat to the biodiversity from agriculture. The conservation planning model developed determines the optimal set of bush fragments for conservation.