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Land-cover change and human population trends in the greater Serengeti ecosystem from 1984–2003

Journal Articles & Books
December, 2012
Africa

The growth of human populations around protected areas accelerates land conversion and isolation, negatively impacting biodiversity and ecosystem function, and can be exacerbated by immigration. It is often assumed that immigration around protected areas is driven by attraction in the form of economic benefits, but in many cases, people may be pushed from their areas of origin toward protected areas. Mitigating the effects of immigration around protected areas necessitates understanding the actual mechanisms causing it, which can be aided by analysis of patterns of land-cover change.

Multi-taxa population connectivity in the Northern Rocky Mountains

Journal Articles & Books
December, 2012

Effective broad-spectrum biodiversity conservation requires that conservation strategies simultaneously meet the needs of multiple species. However, little is known about how maintaining habitat connectivity for one species or species group may also act as an umbrella for other species. We evaluated the degree to which predicted connected habitat for each of 144 different hypothetical organisms expressing range of dispersal abilities and ecological responses to elevation, roads and land cover function as an indicators of connected habitat for the others in the U.S.

Habitat suitability modelling for species at risk is sensitive to algorithm and scale: A case study of Blanding's turtle, Emydoidea blandingii, in Ontario, Canada

Journal Articles & Books
December, 2012
Canada

Species distribution modelling (SDM) can help conservation by providing information on the ecological requirements of species at risk. We developed habitat suitability models at multiple spatial scales for a threatened freshwater turtle, Emydoidea blandingii, in Ontario as a case study. We also explored the effect of background data selection and modelling algorithm selection on habitat suitability predictions. We used sighting records, high-resolution land cover data (25m), and two SDM techniques: boosted regression trees; and maximum entropy modelling.

Landscape metrics as indicators of the structural landscape changes – two case studies from the Czech Republic after 1948

Journal Articles & Books
December, 2012
Czech Republic

The composition and configuration of landscape elements as well as their size and shape co-determine the character of the flows and processes in the landscape. Using remote sensing data and landscape metrics, this article sets out to analyse changes in the landscape structure at two different spatial scales, focusing on two study areas in the Czech Republic in the latter half of the twentieth century.

Assessment of Land use/land cover Change in the North-West District of Delhi Using Remote Sensing and GIS Techniques

Journal Articles & Books
December, 2012
India

Land is one of the prime natural resources. A city grows not only by population but also by changes in spatial dimensions. Urban population growth and urban sprawl induced land use changes and land transformation. The land transformation is a natural process and cannot be stopped but it can be regulated. Many geographical changes at the urban periphery are associated with the transfer of land from rural to urban purpose. There is an urgent need for fast growing areas like Delhi, which can be easily done by high-resolution remote sensing data.

Habitats of Suburban Barred Owls (Strix varia) and Red-Shouldered Hawks (Buteo lineatus) in Southwestern Ohio1

Journal Articles & Books
December, 2012

Little is known about the habitat and ecology of suburban Barred Owls (Strix varia), a species sometimes considered the nocturnal equivalent of Red-shouldered Hawks (Buteo lineatus). We compared nesting habitat of Barred Owls to that of Red-shouldered Hawks nesting in suburban and urban areas, in and near the city of Cincinnati, Ohio, to determine whether any features distinguished owl nest sites from hawk nest sites.

distance dependent contagion function for vector-based data

Journal Articles & Books
December, 2012

Landscape pattern is of primary interest to landscape ecologists and landscape metrics are used to quantify landscape pattern. Metrics are commonly defined and calculated on raster-based land cover maps. One metric is the contagion, existing in several versions, e.g., unconditional and conditional, used as a measure of fragmentation. However, mapped data is sometimes in vector-based format or there may be no mapped data but only a point sample. In this study a definition of contagion for such cases is investigated.

Long term analysis of PALS soil moisture campaign measurements for global soil moisture algorithm development

Journal Articles & Books
December, 2012

An important component of satellite-based soil moisture algorithm development and validation is the comparison of coincident remote sensing and in situ observations that are typically provided by intensive field campaigns. The planned NASA Soil Moisture Active Passive (SMAP) mission has unique requirements compared to previous soil moisture satellite programs because both active and passive microwave observations are needed. The primary source of these combined observations has been an aircraft-based SMAP simulator called PALS (Passive and Active L-band System).

effective approach for land-cover classification from airborne lidar fused with co-registered data

Journal Articles & Books
December, 2012

Airborne lidar provides accurate height information of objects on the earth and has been recognized as a reliable and accurate surveying tool in many applications. In particular, lidar data offer vital and significant features for urban land-cover classification, which is an important task in urban land-use studies. In this article, we present an effective approach in which lidar data fused with its co-registered images (i.e.

Land-cover classification of an intra-urban environment using high-resolution images and object-based image analysis

Journal Articles & Books
December, 2012
Brazil

Detailed, up-to-date information on intra-urban land cover is important for urban planning and management. Differentiation between permeable and impermeable land, for instance, provides data for surface run-off estimates and flood prevention, whereas identification of vegetated areas enables studies of urban micro-climates. In place of maps, high-resolution images, such as those from the satellites IKONOS II, Quickbird, Orbview and WorldView II, can be used after processing.

synthesis of rates and controls on elemental mercury evasion in the Great Lakes Basin

Journal Articles & Books
December, 2012

Rates of surface-air elemental mercury (Hg⁰) fluxes in the literature were synthesized for the Great Lakes Basin (GLB). For the majority of surfaces, fluxes were net positive (evasion). Digital land-cover data were combined with representative evasion rates and used to estimate annual Hg⁰ evasion for the GLB (7.7 Mg/yr). This value is less than our estimate of total Hg deposition to the area (15.9 Mg/yr), suggesting the GLB is a net sink for atmospheric Hg.

Piospheres and Pastoralists: Vegetation and Degradation in Steppe Grasslands

Journal Articles & Books
December, 2012
China
Mongolia
Eastern Asia

The Mongolian plateau in East Asia is part of a new hotspot of land cover change. Recent human activity and natural forces have degraded grasslands in northern China with the southern Mongolia steppe similarly vulnerable. Investigating vegetation patterns at piospheres (the area around water points) can identify herder influence on pasture conditions. Through fieldwork and remote sensing this paper examines plant density and species richness at water sources to establish land cover patterns in two Mongolian provinces where overgrazing is thought to be the major cause of degradation.