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Raptor Presence Along an Urban–Wildland Gradient: Influences of Prey Abundance and Land Cover

Journal Articles & Books
December, 2014

Native animals are affected differently by urbanization. Some species respond favorably and thrive in human-dominated landscapes, but others are extirpated. Raptors are often sensitive to changes in land cover and prey abundance. We therefore used a combination of broadcast surveys and incidental observations while spot-mapping to evaluate the influences of these two variables on the presence of raptors at 21 sites from 2004–2008 along an urban-to-wildland gradient in western Washington, U.S.A.

Soil erosion and sediment fluxes analysis: a watershed study of the Ni Reservoir, Spotsylvania County, VA, USA

Journal Articles & Books
December, 2014
United States of America

Anthropogenic forces that alter the physical landscape are known to cause significant soil erosion, which has negative impact on surface water bodies, such as rivers, lakes/reservoirs, and coastal zones, and thus sediment control has become one of the central aspects of catchment management planning. The revised universal soil loss equation empirical model, erosion pins, and isotopic sediment core analyses were used to evaluate watershed erosion, stream bank erosion, and reservoir sediment accumulation rates for Ni Reservoir, in central Virginia.

Assessing impact of urban impervious surface on watershed hydrology using distributed object-oriented simulation and spatial regression

Journal Articles & Books
December, 2014

In this study, we investigated the relationship between watershed characteristics and hydrology using high spatial resolution impervious surface area (ISA), hydrologic simulations and spatial regression. We selected 20 watersheds at HUC 12 level with different degrees of urbanization and performed hydrologic simulation using a distributed object-oriented rainfall and runoff simulation model. We extracted the discharge per area and ratio of runoff to base flow from simulation results and used them as indicators of hydrology pattern.

impacts of urbanization on air quality over the Pearl River Delta in winter: roles of urban land use and emission distribution

Journal Articles & Books
December, 2014

In this study, ideal but realistic numerical experiments are performed to explore the relative effects of changes in land use and emission distribution on air quality in the Pearl River Delta (PRD) region in winter. The experiments are accomplished using the Lagrangian particle transport and dispersion model FLEXPART coupled with the Weather Research and Forecasting model under different scenarios.

Importance of closed landfills as green space in urbanized areas: ecological assessment using carabid beetles

Journal Articles & Books
December, 2014

In a closed landfill, we investigated the diversity and ecological characters of carabid beetles to understand the ecological importance of closed landfills that have the potential as a multi-functional habitat for improving biodiversity in urbanized areas. In addition, we studied the influence of environmental factors (vegetation structure, soil) on distribution and diversity of carabid beetles. A total of 92,495 individuals representing 15 carabid species were collected from the closed landfill.

Relationship between land use classification and grass shrimp Palaemonetes spp. population metrics in coastal watersheds

Journal Articles & Books
December, 2014

Estuaries in the southeastern USA have experienced increased loading of contaminants from nonpoint source runoff as well as changes in habitat (e.g., loss of wetlands) due to urbanization. These changes may pose significant risks to estuarine fauna, including crustaceans. Several studies have shown relationships between land use classification and levels of stress in estuarine populations. The grass shrimp of the genus Palaemonetes is one of the dominant species found in estuarine tidal creeks, accounting for more than 50� % of all macropelagic fauna.

Potential Impacts and Management Implications of Climate Change on Tampa Bay Estuary Critical Coastal Habitats

Journal Articles & Books
December, 2014

The Tampa Bay estuary is a unique and valued ecosystem that currently thrives between subtropical and temperate climates along Florida’s west-central coast. The watershed is considered urbanized (42� % lands developed); however, a suite of critical coastal habitats still persists. Current management efforts are focused toward restoring the historic balance of these habitat types to a benchmark 1950s period. We have modeled the anticipated changes to a suite of habitats within the Tampa Bay estuary using the sea level affecting marshes model under various sea level rise (SLR) scenarios.

LAND RESOURCES OF THE MEDITERRANEAN: STATUS, PRESSURES, TRENDS AND IMPACTS ON FUTURE REGIONAL DEVELOPMENT

Journal Articles & Books
December, 2014
Algeria
Libya
Egypt
Western Asia
Northern Africa

The Mediterranean region covers about 854 million ha, but only 118 million (or 14 per cent) are suitable for agricultural production. In North Africa and the Middle East (MENA), agricultural land covers about 5 per cent; in Egypt and Algeria, it occupies less than 4 per cent and, in Libya, less than 2 per cent of the total national land area. Across the Mediterranean region land use divides between natural pastures/rangelands (ca. 15 per cent), forests and woodlands (ca. 8 per cent), with the ca.

novel building change index for automatic building change detection from high-resolution remote sensing imagery

Journal Articles & Books
December, 2014

In pace with rapid urbanization, urban areas in many countries are undergoing huge changes. The large spectral variance and spatial heterogeneity within the ‘buildings’ land cover class, as well as the similar spectral properties between buildings and other urban structures, make building change detection a challenging problem. In this work, we propose a set of novel building change indices (BCIs) by combining morphological building index (MBI) and slow feature analysis (SFA) for building change detection from high-resolution imagery.

Soil degradation in environmentally sensitive areas driven by urbanization: an example from Southeast Europe

Journal Articles & Books
December, 2014
Greece

Rapid urbanization together with policy ineffectiveness in controlling urban growth is often associated to soil and land degradation in both the developing and developed world. The present study analyses the relationship between urban expansion and soil degradation in an arid Mediterranean region (Attica, Greece) where the compact settlement pattern has been replaced by low‐density urban development. The study area is one of the most densely populated areas in the Mediterranean basin that has experienced an impressive growth in population during the last 60� yr.

equilibrium analysis of the land use structure in the Yunnan Province, China

Journal Articles & Books
December, 2014
China
Global

Global land use structure is changing rapidly due to unceasing population growth and accelerated urbanization, which leads to fierce competition between the rigid demand for built-up area and the protection of cultivated land, forest, and grassland. It has been a great challenge to realize the sustainable development of land resources.

Urban Morphology Drives the Homogenization of Tree Cover in Baltimore, MD, and Raleigh, NC

Journal Articles & Books
December, 2014

Heterogeneous land cover patterns contribute to unique ecological conditions in cities and little is known about the drivers of these patterns among cities. We studied tree cover patterns in relationship to urban morphology (for example, housing density, parcel size), socioeconomic factors (for example, education, income, lifestyle characteristics), and historical legacies in Baltimore, Maryland, and Raleigh, North Carolina.