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Dynamics of a Community of Dominant Woody Riparian Species Along a Coastal River of Texas

Journal Articles & Books
декабря, 2013

Little is known about the structure of riparian communities within the central Gulf coast of Texas. We present a phytosociological description of the riparian corridor within two contiguous sites along the Mission River in Refugio County, Texas, that differ in respect to tidal influence along the river, and compare this woody riparian community to others in Texas. In summer 2009 and 2010, we established 33 transects perpendicular to the river after reviewing digital data from ArcMap 9.3.1 on elevation, edaphic characteristics, uses of land, and cover of land and wetland.

Forecasting crop yield using remotely sensed vegetation indices and crop phenology metrics

Journal Articles & Books
декабря, 2013
United States of America

We used data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) in association with county-level data from the United States Department of Agriculture (USDA) to develop empirical models predicting maize and soybean yield in the Central United States. As part of our analysis we also tested the ability of MODIS to capture inter-annual variability in yields. Our results show that the MODIS two-band Enhanced Vegetation Index (EVI2) provides a better basis for predicting maize yields relative to the widely used Normalized Difference Vegetation Index (NDVI).

Trade-offs between land use intensity and avian biodiversity in the dry Chaco of Argentina: A tale of two gradients

Journal Articles & Books
декабря, 2013
Argentina

Studies to assess the relationship between agriculture production and biodiversity conservation usually focus on one gradient ranging from a natural reference land cover type (typically forest) to an intensive productive land use. However, many semi-arid ecoregions such as the dry Chaco are characterized by a mosaic of different land covers, including natural grasslands and woody vegetation with different degrees of transformation, frequently aimed at meat production.

Spatial Variation of Eurasian Eagle-Owl Diets in Wetland and Non-Wetland Habitats in West-Central Korea

Journal Articles & Books
декабря, 2013

The diet of the Eurasian Eagle-Owl (Bubo bubo) was studied in two different land-cover types: wetlands and non-wetlands. We analyzed 1458 prey items obtained from 924 pellets and 534 prey remains collected in 34 territories in west-central Korea. Diet composition differed significantly between the two habitats: diet was mainly birds (68.9% by number; 85.3% by biomass) in wetlands, but was dominated by mammals (38.7% by number; 64.7% by biomass) in non-wetlands.

Sustaining protected areas: Identifying and controlling deforestation and forest degradation drivers in the Ankasa Conservation Area, Ghana

Journal Articles & Books
декабря, 2013
Ghana
Africa

Although protected areas in Africa contain possibly the highest repositories of carbon and thus can play a role in mitigating the effects of climate change through carbon sequestration, they are threatened due to increasing levels of deforestation and forest degradation (DFD). However, little information is available on the on-site causes of DFD in these areas. This paper estimates the levels of DFD and identifies the drivers in the Ankasa Conservation Area (ACA) in Ghana as a case study. A survey was used to identify both direct and underlying factors that promote the DFD.

Using algal metrics and biomass to evaluate multiple ways of defining concentration-based nutrient criteria in streams and their ecological relevance

Journal Articles & Books
декабря, 2013
United States of America

We examined the utility of nutrient criteria derived solely from total phosphorus (TP) concentrations in streams (regression models and percentile distributions) and evaluated their ecological relevance to diatom and algal biomass responses. We used a variety of statistics to characterize ecological responses and to develop concentration-based nutrient criteria (derived from ecological effects) for streams in Connecticut, USA, where urbanization is the primary cause of watershed alteration.

Mapping global land system archetypes

Journal Articles & Books
декабря, 2013

Land use is a key driver of global environmental change. Unless major shifts in consumptive behaviours occur, land-based production will have to increase drastically to meet future demands for food and other commodities. One approach to better understand the drivers and impacts of agricultural intensification is the identification of global, archetypical patterns of land systems. Current approaches focus on broad-scale representations of dominant land cover with limited consideration of land-use intensity.

Habitat selection by breeding rock ptarmigan Lagopus muta helvetica males in the western Italian Alps

Journal Articles & Books
декабря, 2013

Knowledge of resource selection patterns can provide important information for species conservation. During spring 2010 and 2011, we investigated habitat selection by territorial rock ptarmigan Lagopus muta helvetica males in a protected area of the western Italian Alps. We located males from 30 randomly selected survey points, and we measured the proportions of cover-type categories found within a 37-ha area surrounding each observed bird using three classification maps of differing information and resolution.

Assessment of groundwater vulnerability to nonpoint source pollution in a Mediterranean coastal zone (Mersin, Turkey) under conflicting land use practices

Journal Articles & Books
декабря, 2013
Turkey

Groundwater resources of the Tarsus coastal plain (Mersin, Turkey) are being exploited heavily for a variety of purposes and they are under a serious threat from nonpoint source pollution from the conflicting land use practices and saltwater intrusion due to overpumping. In this study, vulnerability of groundwater to nonpoint source pollution was assessed using GIS techniques and employing both Generic and Pesticide DRASTIC models. Calculated vulnerability indices ranged between 68–206 and 69–236 for Generic and Pesticide DRASTIC, respectively.

Coyote Land Use Inside and Outside Urban Parks

Journal Articles & Books
декабря, 2013

Coyotes (Canis latrans) have expanded to live in urban areas with limited natural habitat. A year long coyote howl survey combined with geospatial information systems (GIS) was applied to locate populations within a metropolitan region, to determine the habitats where coyotes most frequently occur, and to estimate group sizes within this urbanized region. Surveys were conducted along the perimeters of natural areas and urban-residential communities.

Assessing net carbon sequestration on urban and community forests of northern New England, USA

Journal Articles & Books
декабря, 2013
United States of America

Urban and community forests play an important role in the overall carbon budget of the USA. Accurately quantifying carbon sequestration by these forests can provide insight for strategic planning to mitigate greenhouse gas effects on climate change. This study provides a new methodology to estimate net forest carbon sequestration (FCS) in urban and community lands of northern New England using ground based forest growth rates, housing density data, satellite derived land cover and tree canopy cover maps at the county level.

Land subsidence and declining water resources in Quetta Valley, Pakistan

Journal Articles & Books
декабря, 2013
Pakistan
Afghanistan

Extensive groundwater withdrawals in urban areas may cause water shortages, land subsidence, and water quality problems. The Quetta Valley is the largest population center in Balochistan province in western Pakistan. This area is arid and groundwater is the main water source for domestic and agricultural use. This work presents global positioning system (GPS) data and assessment of spatial and temporal variations in water levels. GPS data from two stations from mid-2006 to the beginning of 2009 show subsidence rate of 10� cm\year.