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Public Water Supply Protection Value of Forests: A Watershed-Scale Ecosystem Services Analysis Based upon Total Organic Carbon

Journal Articles & Books
december, 2014

We developed a cost-based methodology to assess the value of forested watersheds to improve water quality in public water supplies. The developed methodology is applicable to other source watersheds to determine ecosystem services for water quality. We assess the value of forest land for source water mitigation of total organic carbon (TOC) through the use of linked watershed and reservoir simulation models and cost-based valuation economics. Watershed modeling results indicated that expected urbanization will increase TOC loads to Converse Reservoir (Mobile, AL).

Avian diversity in a suburban park system: current conditions and strategies for dealing with anticipated change

Journal Articles & Books
december, 2014
United States of America

A growing trend towards increased urbanization emphasizes the role of suburban parks in wildlife conservation. Spatial planning aimed at maintaining biological diversity and functionality must consider how changes at landscape and more local scales will influence the biotic structure of urban areas. From May 2006 to July 2010, bird surveys were conducted in three metropolitan parks in Cleveland, Ohio, USA.

Modifications in vegetation cover and surface albedo during rapid urbanization: a case study from South China

Journal Articles & Books
december, 2014

The green vegetation fraction (GVF) and surface albedo are important land surface parameters often used for validation of climate and land surface models that are influenced largely by environmental gradients and human activities. In this study, fine resolution GVF and albedo values derived from Landsat Thematic Mapper/Enhanced Thematic Mapper Plus images from 1990 to 2000 were used to examine the relationship of both GVF and albedo values to the spatial gradients of parameters related to dramatic urbanization in the Greater Guangzhou metropolitan area, Guangdong Province, in South China.

Fire Management, Managed Relocation, and Land Conservation Options for Long‐Lived Obligate Seeding Plants under Global Changes in Climate, Urbanization, and Fire Regime

Journal Articles & Books
december, 2014

Most species face multiple anthropogenic disruptions. Few studies have quantified the cumulative influence of multiple threats on species of conservation concern, and far fewer have quantified the potential relative value of multiple conservation interventions in light of these threats.

Land fragmentation and variation of ecosystem services in the context of rapid urbanization: the case of Taizhou city, China

Journal Articles & Books
december, 2014
China

This study analyzes land use dynamics, land fragmentation, variation of ecosystem service value (ESV), and the underlying driving forces in the context of rapid urbanization in Taizhou city, China. An integrated approach utilizing geographic information system and remote sensing was used to analyze land use/land cover change, spatiotemporal patterns of land fragmentation and variation of ESV over the period of 1995–2010.

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.