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Comprehensive evaluation of the climate-change implications of shifting land use between forest and grassland: New Zealand as a case study

Journal Articles & Books
Dezembro, 2012
Nova Zelândia

The transition of land between forest and grassland has important implications for greenhouse gas emissions and removals. In this paper, we use New Zealand as a case study to comprehensively assess, compare and quantify the net climate change impact of shifting land use between temperate forest and grassland. Forests store large amounts of carbon in their biomass, whereas grasslands contain relatively little biomass carbon. These biomass changes tend to dominate the carbon balance under land-use change.

Assessing the impacts of economic and climate changes on land-use in mountain regions: A spatial dynamic modeling approach

Journal Articles & Books
Dezembro, 2012
Suíça

Future land-use changes are predicted to be influenced by both climate-driven environmental changes and concomitant changes in local economic conditions. Assessing the impact of climate change on ecosystems, and the goods and services that they provide, therefore requires an understanding of the dynamic link between land-cover, ecosystem services and economic-driven land-use decisions. The economic land allocation model (ALUAM) simulates the competition between forest and a range of agricultural land-uses to estimate land-use conversions in a spatially explicit manner at high resolution.

Simulating urban growth processes incorporating a potential model with spatial metrics

Journal Articles & Books
Dezembro, 2012
China

Urbanization is one phenomena that drives land use pattern change. Persistent rapid urbanization is associated with depletion of natural resources and worsening conditions in the urban environment. Monitoring urban development is, therefore, an absolute necessity in order to assure sustainable cities in the future. The main objective of this paper is to develop and apply an urban growth potential model incorporating spatial metrics. The model has been tested in Jinan City, China. Firstly, two satellite images (1989 and 2004 SPOT) were used to extract the land-cover.

Paired-site approach for studying soil organic carbon dynamics in a Mediterranean semiarid environment

Journal Articles & Books
Dezembro, 2012

This work investigated the effects of land cover and land-use change (LUC) on the ability of a soil to store carbon (C) and reduce carbon dioxide (CO₂) emissions, in a Mediterranean area. Using a paired-site approach, we estimated the effect of land-cover change on the C stock from 1972 to 2008 in a natural reserve (Grotta di Santa Ninfa) in western Sicily. We selected 15 paired sites representative of five LUCs.

definition of potential infiltration areas in Guaratinguetá watershed, Paraíba do Sul Basin, Southeastern Brazil: an integrated approach using physical and land-use elements

Journal Articles & Books
Dezembro, 2012

This work describes the methodological approach used for mapping the potential infiltration areas of the Guaratinguetá watershed (160 km2), situated in Southeastern Brazil. The method is considered a qualitative approach, which takes into account thematic maps (geology, pedology, geomorphology, and land use/land cover) and the precipitation spatial distribution. A group of experts in Earth Sciences and Geotechnical Engineering has applied an infiltration potential scale factor that ranges from 5 (highest influence) to 1 (lowest influence).

Multinomial regression for analyzing macroinvertebrate assemblage composition data

Journal Articles & Books
Dezembro, 2012
Estados Unidos

Macroinvertebrate species composition data are often expressed as proportional abundances when assessing water-quality conditions or responses to disturbance. Proportional abundances represent the probability of belonging to one of many mutually exclusive and exhaustive groups (taxa). Proportional abundances have some unique properties that must be considered when analyzing these data: 1) the probabilities of group membership must sum to 1 and 2) a change in any 1 group affects all other groups.

multi-level analysis of the relationship between environmental factors and questing Ixodes ricinus dynamics in Belgium

Journal Articles & Books
Dezembro, 2012
Bélgica
Europa

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.

Optimal conservation investment for a biodiversity‐rich agricultural landscape

Journal Articles & Books
Dezembro, 2012

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.

Quality assessment of Landsat surface reflectance products using MODIS data

Journal Articles & Books
Dezembro, 2012

Surface reflectance adjusted for atmospheric effects is a primary input for land cover change detection and for developing many higher level surface geophysical parameters. With the development of automated atmospheric correction algorithms, it is now feasible to produce large quantities of surface reflectance products using Landsat images. Validation of these products requires in situ measurements, which either do not exist or are difficult to obtain for most Landsat images.

Evaluation of dynamic linkages between evapotranspiration and land-use/land-cover changes with Landsat TM and ETM+ data

Journal Articles & Books
Dezembro, 2012
China

Complexity embedded in coastal management leads to numerous questions as to how inherent spatial and temporal linkages among evapotranspiration (ET), depth to groundwater and land-use/land-cover change (LUCC) could affect the dynamics among these seemingly unrelated events. This article aims to address such unique dynamics in the nexus of physical geography and ecohydrology.

Hydrogeologic and landscape controls of dissolved inorganic nitrogen (DIN) and dissolved silica (DSi) fluxes in heterogeneous catchments

Journal Articles & Books
Dezembro, 2012
Luxemburgo

This paper examines the combined effects of catchment complexity in terms of physiography, land use patterns, and lithology on the export of dissolved inorganic nitrogen and dissolved silica from heterogeneous nested catchments in the Grand-Duchy of Luxembourg. Using results from water quality monitoring at 24 sampling sites, we determined the first-order controls on these fluxes.

LiDAR-Landsat data fusion for large-area assessment of urban land cover: Balancing spatial resolution, data volume and mapping accuracy

Journal Articles & Books
Dezembro, 2012
Estados Unidos

The structural characteristics of Light Detection and Ranging (LiDAR) data are increasingly used to classify urban environments at fine scales, but have been underutilized for distinguishing heterogeneous land covers over large urban regions due to high cost, limited spectral information, and the computational difficulties posed by inherently large data volumes.