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Source populations and roads affect American black bear recolonization

Journal Articles & Books
Décembre, 2015
États-Unis d'Amérique

Understanding species distributions and population responses to environmental parameters is important for addressing landscape-level species conservation. We assessed American black bear (Ursus americanus) resource selection based on spatial distribution of a recolonizing population in Mississippi, USA. Given the philopatric behavior of female bears and the risk-disturbance hypothesis, we predicted that bears recolonizing Mississippi would occupy areas close to their source population but avoid areas near roads and with greater human population density.

index of human alteration of lake shore morphology

Journal Articles & Books
Décembre, 2015
Europe

Morphological degradation constitutes one of the most severe threats to the ecological integrity of lakes. The development of biotic assessment methods for human lake shore alterations using littoral macroinvertebrates requires quantification of the degree of degradation by a stressor index and is complicated through simultaneous physical pressures that alter natural habitat structure.

Impact of land‐use changes on soil hydraulic properties of Calcaric Regosols on the Loess Plateau, NW China

Journal Articles & Books
Décembre, 2015
Chine

Vegetation restoration efforts (planting trees and grass) have been effective in controlling soil erosion on the Loess Plateau (NW China). Shifts in land cover result in modifications of soil properties. Yet, whether the hydraulic properties have also been improved by vegetation restoration is still not clear. The objective of this paper was to understand how vegetation restoration alters soil structure and related soil hydraulic properties such as permeability and soil water storage capacity.

Feasibility of Inter-Comparing Airborne and Spaceborne Observations of Radar Backscattering Coefficients

Journal Articles & Books
Décembre, 2015

This paper investigates the feasibility of using an airborne synthetic aperture radar (SAR) to validate spaceborne SAR data. This is directed at soil moisture sensing and the recently launched soil moisture active passive (SMAP) satellite. The value of this approach is related to the fact that vicarious targets such as rain forests and oceans calibrate only the extrema of backscattering coefficients (σ0) and that the relationship between soil moisture and σ0 is nonlinear.

Woody Plant-Cover Dynamics in Argentine Savannas from the 1880s to 2000s: The Interplay of Encroachment and Agriculture Conversion at Varying Scales

Journal Articles & Books
Décembre, 2015
Argentine

Woody plant-cover dynamics can alter the provisioning of ecosystem services that humans rely on. However, our understanding of such dynamics today is often limited by the availability of reliable and detailed land-cover information in the past, before the onset of remote sensing technologies. In this study, we carefully extracted information from historical maps of the Caldenal savannas of central Argentina in the 1880s to generate a woody cover map that we compared to a 2000s dataset. Over about the last 120 years, woody cover increased across approximately 12,200 km²(14.2% of the area).

Mapping hotspots of malaria transmission from pre-existing hydrology, geology and geomorphology data in the pre-elimination context of Zanzibar, United Republic of Tanzania

Journal Articles & Books
Décembre, 2015
Tanzania

BACKGROUND: Larval source management strategies can play an important role in malaria elimination programmes, especially for tackling outdoor biting species and for eliminating parasite and vector populations when they are most vulnerable during the dry season. Effective larval source management requires tools for identifying geographic foci of vector proliferation and malaria transmission where these efforts may be concentrated.

Littoral macroinvertebrate communities of dune lakes in the far north of New Zealand

Journal Articles & Books
Décembre, 2015
Nouvelle-Zélande

The littoral macroinvertebrate faunas of 17 dune lakes on the Aupouri Peninsula in northern New Zealand were examined. Land cover of individual catchments was principally sand dunes and scrub, plantation forest, pasture, or a mixture of plantation forest and pasture. Sampling was concentrated in the sedge beds, submerged macrophytes and surface sediment layers of the littoral zone. Sixty-eight invertebrate taxa were recorded, 11–30 per lake. Relative abundance of major faunal groups differed considerably among lakes but a core group of common species was found in three quarters of them.

How resilient are African woodlands to disturbance from shifting cultivation?

Journal Articles & Books
Décembre, 2015
Tanzania
Afrique

Large parts of sub‐Saharan Africa are experiencing rapid changes in land use and land cover, driven largely by the expansion of small‐scale shifting cultivation. This practice creates complex mosaic landscapes with active agricultural fields and patches of mature woodland, interspersed with remnant patches in various stages of regrowth.

Functional diversity enhances the resistance of ecosystem multifunctionality to aridity in Mediterranean drylands

Journal Articles & Books
Décembre, 2015

We used a functional trait‐based approach to assess the impacts of aridity and shrub encroachment on the functional structure of Mediterranean dryland communities (functional diversity (FD) and community‐weighted mean trait values (CWM)), and to evaluate how these functional attributes ultimately affect multifunctionality (i.e. the provision of several ecosystem functions simultaneously). Shrub encroachment (the increase in the abundance/cover of shrubs) is a major land cover change that is taking place in grasslands worldwide.

To fledge or not to fledge: factors influencing the number of eggs and the eggs-to-fledglings rate in White Storks Ciconia ciconia in an agricultural environment

Journal Articles & Books
Décembre, 2015

Numerous studies have explored the relationship between environmental factors and White Stork Ciconia ciconia reproduction, mainly expressing breeding success as the number of fledglings. Nonetheless, one of the most critical life-history stages in birds falls between egg-laying and fledging, and identifying the factors causing offspring mortality during this period provides valuable knowledge. We quantified the number of laid White Stork eggs and the proportion of eggs that turned into fledglings in an agriculture-dominated region in Eastern Germany.

Estimating upper soil horizon carbon stocks in a permafrost watershed of Northeast Siberia by integrating field measurements with Landsat-5 TM and WorldView-2 satellite data

Journal Articles & Books
Décembre, 2015

Arctic soils contain three times as much carbon (C) as all aboveground biomass distributed globally, much of which is stored in permafrost soils. Here, we (1) determine the predictability of estimating soil organic carbon (SOC) using different satellite data, classifications, and methods; (2) estimate the quantity and distribution of SOC for the top 10 cm for the Ambolikha River watershed (~121 km ²) in northeast Siberia, a sub-watershed of the Kolyma River; and (3) produce a hybrid SOC map through data fusion, combining the strengths of each data type.

Comparing the effects of an NLCD-derived dasymetric refinement on estimation accuracies for multiple areal interpolation methods

Journal Articles & Books
Décembre, 2015

Comparability among population data enumerated within different time periods may be complicated by changing enumeration boundaries over time. Areal interpolation methods are commonly used to solve such zoning incompatibilities, but are frequently based on the questionable assumption of homogeneous population density within the different zones. To achieve more accurate estimates, land cover or other ancillary data may be used to better characterize the underlying source zone population density surface prior to areal interpolation.