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Effect of catchment properties on runoff coefficient in a karst area of southwest China

Journal Articles & Books
Dezembro, 2014
China

Frequent human activities and climate change in the karst region of southwest China since the 1950s have led to the investigation of response of runoff to climate and catchment properties. Runoff coefficient (Rc) as an expression variable of the catchment response to rainfall is important to describe runoff dynamics and to estimate available streamflow for utilization. In this study, the equations of Rc associated with its attributors of climate condition and catchment property were derived using the Budyko framework.

Acacia nilotica-based silvipastoral systems for resource conservation and improved productivity from degraded lands of the Lower Himalayas

Journal Articles & Books
Dezembro, 2014
Índia

High population density and unscientific land use practices have induced severe land degradation in the fragile Lower Himalayan ecosystem of India. Land cover management has been an effective strategy in managing land degradation through the reduction of water, soil and nutrient losses and improvement in soil fertility and quality.

Global albedo change and radiative cooling from anthropogenic land-cover change, 1700 to 2005 based on MODIS, land-use harmonization, radiative kernels and reanalysis

Journal Articles & Books
Dezembro, 2014
Global

Widespread anthropogenic land-cover change over the last five centuries has influenced the global climate system through both biogeochemical and biophysical processes. Models indicate that warming from carbon emissions associated with land cover conversion have been partially offset if not outweighed by cooling from elevated albedo, but considerable uncertainty remains partly because of uncertainty in model treatments of albedo.

approach for the long-term 30-m land surface snow-free albedo retrieval from historic Landsat surface reflectance and MODIS-based a priori anisotropy knowledge

Journal Articles & Books
Dezembro, 2014
Estados Unidos

Land surface albedo has been recognized by the Global Terrestrial Observing System (GTOS) as an essential climate variable crucial for accurate modeling and monitoring of the Earth’s radiative budget. While global climate studies can leverage albedo datasets from MODIS, VIIRS, and other coarse-resolution sensors, many applications in heterogeneous environments can benefit from higher-resolution albedo products derived from Landsat.

Operational Data Fusion Framework for Building Frequent Landsat-Like Imagery

Journal Articles & Books
Dezembro, 2014
Índia

An operational data fusion framework is built to generate dense time-series Landsat-like images for a cloudy region by fusing Moderate Resolution Imaging Spectroradiometer (MODIS) data products and Landsat imagery. The Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) is integrated in the framework. Compared to earlier implementations of STARFM, several improvements have been incorporated in the operational data fusion framework.

Long-term vegetation development on a wildfire slope in Innerzwain (Styria, Austria)

Journal Articles & Books
Dezembro, 2014
Áustria

Forest fires in mountainous areas can cause severe deforestation which can potentially trigger secondary natural hazards like debris falls and avalanches. We documented an extreme case study for the range of possible post-fire land cover (LC) dynamics. We investigated a 15-ha, steep (10°–65°) burnt slope in Styria (Austria) at elevation of 760°-113 m, which burned in 1946 and has not fully recovered to date. Seven 8-class legend LC maps were produced (1954, 1966, 1973, 1982, 1998, 2004, 2009) and integrated in a vector-based GIS, mainly by on-screen interpretation of aerial photos.

influence of land use patterns on water quality at multiple spatial scales in a river system

Journal Articles & Books
Dezembro, 2014
China

The influence of land use patterns on water quality in a river system is scale‐dependent. In this study, a four‐order hierarchical arrangement method was used to select water sampling sites and to delineate sub‐basins in the Daliao River Basin, China. The 20 sub‐basins were classified into four spatial scales that represented four different stream orders. Pearson correlation analysis was used to quantify relationships between land use composition and the river's physical‐chemical variables for all samples collected.

Pollinator body size mediates the scale at which land use drives crop pollination services

Journal Articles & Books
Dezembro, 2014

Ecosystem services to agriculture, such as pollination, rely on natural areas adjacent to farmland to support organisms that provide services. Native insect pollinators depend on natural or semi‐natural land surrounding farms for nesting and alternative foraging resources. Despite interest in conserving pollinators through habitat restoration, the scale at which land use affects pollinators and thus crop pollination services is not well understood. We measured abundance of native, wild bee pollinators and the pollination services they provided to highbush blueberry Vaccinium corymbosum L.

Impact of habitat alteration on endemic Afromontane chameleons: evidence for historical population declines using hierarchical spatial modelling

Journal Articles & Books
Dezembro, 2014
Tanzania

AIM: We map estimated historical population declines resulting from species‐specific models of sensitivity to habitat fragmentation for three forest‐dependent chameleons. LOCATION: East Usambara Mountains, Eastern Arc Mountains, Tanzania. METHODS: We surveyed three chameleon species (Rhampholeon spinosus, Rhampholeon temporalis and Trioceros deremensis) along 32.2� km of transects and used a hierarchical, distance‐sampling model to estimate densities. The model included habitat characteristics at the landscape (patch) and local (transect) scales while accounting for detectability.

Does estuarine health relate to catchment land-cover in the East Kleinemonde system, South Africa?

Journal Articles & Books
Dezembro, 2014
África do Sul
África austral

Temporarily open/closed estuaries in South Africa are being subjected to varying degrees of catchment land-cover transformation. Natural landscapes and hydrological functions are integral to the functioning of estuaries. The relationship between catchment land-cover and the health of the East Kleinemonde Estuary was investigated between 2011 and 2013, using geographic information system (GIS) techniques to delineate and quantify land-cover in the whole catchment, in the lower section of the catchment, and in the 1 km and 100 m buffer zones surrounding the estuary.

Shoreline Change Analysis along the Coast of South Gujarat, India, Using Digital Shoreline Analysis System

Journal Articles & Books
Dezembro, 2014
Índia

Shoreline changes along the south Gujarat coast has been analyzed by using USGS Digital Shoreline Analysis System (DSAS) version 4.3. Multi-temporal satellite images pertaining to 1972, 1990, 2001 and 2011 were used to extract the shoreline. The High water line (HTL) is considered as shoreline and visual interpretation of satellite imageries has been carried out to demarcate the HTL based on various geomorphology and land use & land cover features. The present study used the Linear Regression Method (LRR) to calculate shoreline change rate.