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Linking Land Cover Changes in the Sub‐Alpine and Montane Belts to Changes in a Torrential River

Journal Articles & Books
Diciembre, 2016

Channel changes are the consequence of changes in sediment yield from the slopes and in the connectivity between slopes and channels because of distinct land use and climate impacts. In this study, we investigated the characteristics and evolution of a short reach in the headwater of the Ijuez River, central–southern Pyrenees. Assessment of a series of sedimentary and geomorphic structures confirmed major changes to the valley bottom, mainly related to changes in the intensity of human activity.

Spatial Assessment of Land Degradation Risk for the Okavango River Catchment, Southern Africa

Journal Articles & Books
Diciembre, 2016
África austral
África

The Okavango catchment in southern Africa is subject to environmental as well as socio‐economic transformation processes such as population growth and climate change. The degradation of soil and vegetation by deforestation and overgrazing is one of the downsides of this development, reducing the capacity of the land to provide ecosystem functions and services. In this study, climate simulations are brought together with secondary socioeconomic, pedologic and remote‐sensing data in a GIS‐based assessment of the factors commonly associated with land degradation risk.

Removal efficiency of particulate matters at different underlying surfaces in Beijing

Journal Articles & Books
Diciembre, 2016

Particulate matter (PM) pollution has been increasingly becoming serious in Beijing and has drawn the attention of the local government and general public. This study was conducted during early spring of 2013 and 2014 to monitor the concentration of PM at three different land surfaces (bare land, urban forest, and lake) in the Olympic Park in Beijing and to analyze its effect on the concentration of meteorological factors and the dry deposition onto different land cover types.

Simulating range-wide population and breeding habitat dynamics for an endangered woodland warbler in the face of uncertainty

Journal Articles & Books
Diciembre, 2016

Population viability analyses provide a quantitative approach that seeks to predict the possible future status of a species of interest under different scenarios and, therefore, can be important components of large-scale species’ conservation programs. We created a model and simulated range-wide population and breeding habitat dynamics for an endangered woodland warbler, the golden-cheeked warbler (Setophaga chrysoparia). Habitat-transition probabilities were estimated across the warbler's breeding range by combining National Land Cover Database imagery with multistate modeling.

Evaluation of the Effects of Climate Change on Groundwater Recharge Using a Hybrid Method

Journal Articles & Books
Diciembre, 2016

In this study, a new framework was developed for the estimation of groundwater recharge based on a hybrid method. In this regard, the homogeneous recharge zones were determined by the analytical hierarchy process (AHP). The recharge rates in these zones were calculated using the Thornthwaite and Mather’s method. These zones and their recharge rates were entered into the MODFLOW model. Next, the modeling processes, modification of recharge, and calibration of empirical models were interactively continued in the MODFLOW.

Indicators for spatial–temporal comparisons of ecosystem service status between regions: A case study of the Taihu River Basin, China

Journal Articles & Books
Diciembre, 2016
China

With the development of ecological science, the demand to integrate ecosystem services into ecological management is increasing. Stakeholders are interested in comparing stocks and ability to supply ecosystem services in different regions. However, different areas may have different primary ecosystem services and knowledge of the aggregated value of ecosystem services may be lacking, making comparisons difficult. Relevant indicators that can integrate a group of ecosystem services for comparison are therefore needed.

Monitoring changes in landscape pattern: use of Ikonos and Quickbird images

Journal Articles & Books
Diciembre, 2016
Turquía

This paper aimed to analyze short-term changes in landscape pattern that primarily results from building development in the east coast of Mersin Province (Turkey). Three sites were selected. Ikonos (2003) and Quickbird (2009) images for these sites were classified, and land cover transformations were quantitatively analyzed using cross-tabulation of classification results. Changes in landscape structure were assessed by comparing the calculated values of area/edge and shape metrics for the earlier and later dates.

Site-scale isotopic variations along a river course help localize drainage basin influence on river food webs

Journal Articles & Books
Diciembre, 2016

In human-impacted rivers, nutrient pollution has the potential to disrupt biodiversity organisation and ecosystem functioning, prompting calls for effective monitoring and management. Pollutants, together with natural variations, can modify the isotopic signature of aquatic organisms. Accordingly, we explored the potential of isotopic variations as an indicator of drainage basin influences on river food webs. We assessed stable N and C isotopes within six food webs along a river affected by multiple pollution sources.

critical re-evaluation of controls on spatial and seasonal variations in nitrate concentrations in river waters throughout the River Derwent catchment in North Yorkshire, UK

Journal Articles & Books
Diciembre, 2016

Since mean nitrate concentration along single river channels increases significantly with percent arable land use upstream of sampling points and autumn/early winter flushes in nitrate concentration are widespread, it is generally concluded that farmers contribute most of the nitrate. For the River Derwent in North Yorkshire, the correlation between nitrate concentration and percent arable land use is much poorer when tributary data are included in the equation, because of greater variations in dilution by water draining upland areas and in other N input sources.

Patterns of parasite community dissimilarity: the significant role of land use and lack of distance‐decay in a bat–helminth system

Journal Articles & Books
Diciembre, 2016

Increasing community dissimilarity across geographic distance has been described for a wide variety of organisms and understanding its underlying causes is key to understanding mechanisms driving patterns of biodiversity. Both niche‐based and neutral processes may produce a distance decay relationship; however, disentangling their relative influence requires simultaneous examination of multiple potential drivers.

Predicting species richness and distribution ranges of centipedes at the northern edge of Europe

Journal Articles & Books
Diciembre, 2016
Noruega
Europa

In recent decades, interest in understanding species distributions and exploring processes that shape species diversity has increased, leading to the development of advanced methods for the exploitation of occurrence data for analytical and ecological purposes. Here, with the use of georeferenced centipede data, we explore the importance and contribution of bioclimatic variables and land cover, and predict distribution ranges and potential hotspots in Norway.

Impact of Land Cover on Temperature and Moisture Sensitivity of Soil Organic Matter Mineralization in Subtropical Southeastern China

Journal Articles & Books
Diciembre, 2016
China

Understanding the temperature and moisture sensitivity of soil organic matter (SOM) mineralization variations with changes in land cover is critical for assessing soil carbon (C) storage under global change scenarios. We determined the differences in the amount of SOM mineralization and the temperature and moisture sensitivity of soils collected from six land-cover types, including an orchard, a cropland, and four forests, in subtropical southeastern China.