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Patterns of Tree Distribution within Small Communities of the Sudanian Savanna-Sahel

Peer-reviewed publication
december, 2014
Algeria
Sudan
Burkina Faso
Nigeria
Mauritania
Chad
Mali
Cameroon
Senegal
Central African Republic
South Sudan
Ethiopia
Niger
Eritrea
Africa

Crown diameter and tree density were measured in 52 communities in the Sudan-Sahel using satellite imagery to determine the relationships between rainfall and distance from community center to crown size diameter and tree density. As distance from the community center increased, tree density and crown diameter decreased. As rainfall increased, tree density decreased while crown diameter increased. Distance from the community center is a proxy for age since urbanization and our results indicate that older parts of communities show longer and more consistent tree management.

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.

Changing concepts of city and urban planning practices in Guangzhou (1949–2010): An approach to sustainable urban development

Journal Articles & Books
december, 2014
China

By focusing on Guangzhou, this paper examines how different concepts of city in terms of urban-rural relationships are shaped in transforming China since 1949, and explores how they influence the way in which urban planning are practiced. In the pre-reform era, the city was defined as a productive space under the system of urban-rural segregation established for securing rapid industrialization. Urban planning was thus only concerned with the development of urban areas.

Combining CLUE-S and SWAT models to forecast land use change and non-point source pollution impact at a watershed scale in Liaoning Province, China

Journal Articles & Books
december, 2014
China

Non-point source (NPS) pollution has become a major source of water pollution. A combination of models would provide the necessary direction and approaches designed to control NPS pollution through land use planning. In this study, NPS pollution load was simulated in urban planning, historic trends and ecological protection land use scenarios based on the Conversion of Land Use and its Effect at Small regional extent (CLUE-S) and Soil and Water Assessment Tool (SWAT) models applied to Hunhe-Taizi River Watershed, Liaoning Province, China.

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.