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Broad-Scale Relationships between Shorebirds and Landscapes in the Southern Great Plains

Journal Articles & Books
декабря, 2013

Stopover use by migrating shorebirds is affected by patch-level characteristics of habitat, but the relative influence of broad-scale factors is poorly understood. We conducted surveys of ten 10-km-radius landscapes in north-central Oklahoma from 2007 through 2009 to examine the influence of the amount and composition of wetland habitats and surrounding land cover on shorebird use during migration.

Seroprevalence and risk factors associated with zoonotic parasitic infections in small ruminants in the Greek temperate environment

Journal Articles & Books
декабря, 2013
Greece

A cross-sectional serological study was carried out to screen the sheep and goat population of Thessaly, Greece for evidence of infection with Toxoplasma, Toxocara, Leishmania, and Echinococcus and to determine the risk factors related to herd characteristics, herd management practices, farmer status, and the bioclimatic variables associated with these zoonotic parasitic infections. A total of 540 sheep and goat serum samples were examined. The seroprevalence of infection in all examined animals was 24.5% for Toxoplasma, 32% for Toxocara, 0% for Leishmania and 85.9% for Echinococcus.

Measuring impacts of community forestry program through repeat photography and satellite remote sensing in the Dolakha district of Nepal

Journal Articles & Books
декабря, 2013
Nepal

During the 1990's community-based forest management gained momentum in Nepal. This study systematically evaluates the impacts that this had on land cover change and other associated aspects during the period 1990–2010 using repeat photography and satellite imagery in combination with interviews with community members.

Changes of land cover in the Yarlung Tsangpo River basin from 1985 to 2005

Journal Articles & Books
декабря, 2013

Land cover is closely related to environmental changes and socioeconomic development. Land-cover change in the Tibetan Plateau (TP) is different from that in the lowlands; however, a detailed land-cover change in areas such as the Yarlung Tsangpo River (YTR) basin in the TP has not been reported. To fill this gap, the current study explores the land-cover change between 1985 and 2005 in the YTR basin. The results show that only 1 % of the land cover in the YTR basin changed during this time period.

Complex transformation of the geomorphic regime of channels in the forefield of the Moravskoslezské Beskydy Mts.: Case study of the Morávka River (Czech Republic)

Journal Articles & Books
декабря, 2013
Czech Republic

This paper presents a complex analysis of both the contemporary and the historic development of the geomorphic regime of the transformed reach of the Morávka River in the Czech Carpathians. The assessment concentrates on the conditions and causes of the channel development in the last c. 200years compared with the state of European channels, especially those of the Carpathian zone. The Morávka R. pattern has undergone a rapid change in the last 50years, particularly in connection with the active channel narrowing and massive incision.

Environmental determinants of the spatial distribution of Alaria alata in Hungary

Journal Articles & Books
декабря, 2013
Hungary

Alaria alata is a potential zoonotic parasite, which is widely distributed in Eurasia. To assess the risk of human infection, it is important to know the spatial distribution pattern of the parasite and factors influencing this pattern. To investigate these relationships, 1612 red fox (Vulpes vulpes) carcasses were randomly collected from the whole Hungarian territory, and the intestines were examined by sedimentation and counting technique. The spatial distribution of the parasite was highly clumped.

2010 map estimate of annually tilled cropland within the conterminous United States

Journal Articles & Books
декабря, 2013
United States of America

A ca. 2010, 30m resolution map depicting annually tilled areas across the conterminous United States was developed. Input sources included fouryears, spanning 2008–2011, of annual national-level coverage Cropland Data Layer (CDL) land cover classifications as produced by the National Agricultural Statistics Service. Derived total land area under tillage from the aggregate CDL product equaled 112.8million hectares (278.7million acres).

impacts of shrimp farming on land use, employment and migration in Tumbes, northern Peru

Journal Articles & Books
декабря, 2013
Peru

Export-oriented shrimp aquaculture appeared in the coastal landscape of Peru in the late 1970s. Its rapid development has entailed both positive and negative environmental and socioeconomic impacts across the newly emerging shrimp farming territory of the Tumbes river delta. Here we combine ground surveys and interviews with remote sensing analysis of the transformed environment in order to characterize and quantify the nature, origin and scale of the environmental and social impacts caused by the intrusion of aquaculture.

Land Transitions in Northwest Vietnam: An Integrated Analysis of Biophysical and Socio-Cultural Factors

Journal Articles & Books
декабря, 2013
Vietnam

This paper discusses transitions in land use evidenced by the case of the Suoi Muoi catchment area in NW mountain of Vietnam. Land use transitions were detected from LANDSAT and SPOT satellite images taken over the last 40 years. The maps showing changes in land use were linked with biophysical properties of the land such as slope gradient, elevation and soil type, and cultural characteristic of various ethnic groups by means of logistic regression model.

Spectral similarity-preserving hyperspectral band selection

Journal Articles & Books
декабря, 2013

Due to the high spectral resolution, hyperspectral images (HSI) have been widely used in land cover classification and material identification. Band selection is one of the necessary preprocessings to reduce the data volume and the redundancy therein for the subsequent analysis. Aiming at speeding up the search-based band selection process, this letter proposes a new technique from the perspective of spectral curve shape similarity.

added complications of climate change: understanding and managing biodiversity and ecosystems

Journal Articles & Books
декабря, 2013

Ecosystems around the world are already threatened by land‐use and land‐cover change, extraction of natural resources, biological disturbances, and pollution. These environmental stressors have been the primary source of ecosystem degradation to date, and climate change is now exacerbating some of their effects. Ecosystems already under stress are likely to have more rapid and acute reactions to climate change; it is therefore useful to understand how multiple stresses will interact, especially as the magnitude of climate change increases.

Automated cloud and shadow detection and filling using two-date Landsat imagery in the USA

Journal Articles & Books
декабря, 2013
United States of America

A simple, efficient, and practical approach for detecting cloud and shadow areas in satellite imagery and restoring them with clean pixel values has been developed. Cloud and shadow areas are detected using spectral information from the blue, shortwave infrared, and thermal infrared bands of Landsat Thematic Mapper or Enhanced Thematic Mapper Plus imagery from two dates (a target image and a reference image).