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Urban permeability for birds: An approach combining mobbing-call experiments and circuit theory

Journal Articles & Books
December, 2016

The urban matrix was recently shown to be a mosaic of heterogeneous dispersal habitats. We conducted a playback experiment of mobbing calls to examine the probabilities of forest birds to cross a distance of 50m over urban matrix with different land-cover types in an urban area. We treated the reciprocal of the crossing probabilities as a movement resistance for forest birds. We drew resistance surfaces based on the land-cover maps of urban XXX.

Evaluation of soil erosion risk for watershed management in Shenmu watershed, central Taiwan using USLE model parameters

Journal Articles & Books
December, 2016
Taiwan

This study compiles the latest regional topographic data from field investigation and remote-sensing images to recalculate parameters of the universal soil loss equation (USLE) model of the Shenmu watershed; also to compensate for reduced accuracy of this model on small-scale slopes, this study incorporates soil erosion pin data which were collected periodically to measure the extent of soil erosion.

Aphid parasitoids respond to vegetation heterogeneity but not to fragmentation scale: An experimental field study

Journal Articles & Books
December, 2016

How animal populations respond to habitat manipulations is a central theme in ecology. In recent years, the role that vegetation heterogeneity plays in regulating arthropod populations has received particular attention in both conservation science and agricultural ecology. Numerous observational studies have demonstrated that herbivores and their natural enemies are sensitive to vegetation heterogeneity, but the individual effects of percentage land cover, degree of fragmentation and patch size remain little understood.

multifaceted view on the impacts of shrub encroachment

Journal Articles & Books
December, 2016

Shrub encroachment, a global phenomenon with management implications, is examined in two papers in the current issue of Applied Vegetation Science. Barbosa da Silva et al. show that encroachment simplifies the herbaceous community, and Pittarello et al. illustrate how pastoral practices can restore encroached grasslands. While detrimental effects of shrub encroachment on grassland vegetation are often reported, we argue for a more holistic view when assessing this land‐cover change.

Landscape genetics of a tropical rescue pollinator

Journal Articles & Books
December, 2016
Brazil

Pollination services are increasingly threatened by the loss and modification of natural habitats, posing a risk to the maintenance of both native plant biodiversity and agricultural production. In order to safeguard pollination services, it is essential to examine the impacts of habitat degradation on the population dynamics of key pollinators and identify potential “rescue pollinators” capable of persisting in these human-altered landscapes.

EDITOR'S CHOICE: Coho salmon spawner mortality in western US urban watersheds: bioinfiltration prevents lethal storm water impacts

Journal Articles & Books
December, 2016

Adult coho salmon Oncorhynchus kisutch return each autumn to freshwater spawning habitats throughout western North America. The migration coincides with increasing seasonal rainfall, which in turn increases storm water run‐off, particularly in urban watersheds with extensive impervious land cover. Previous field assessments in urban stream networks have shown that adult coho are dying prematurely at high rates (>50%).

Relating landscape to stream nitrate-N levels in a coastal eastern-Atlantic watershed (Portugal)

Journal Articles & Books
December, 2016
Portugal

We apply a linear regression mixed effects model to explore the influence of landscape factors on nitrate-N concentrations in a coastal watershed of Portugal. Landscape composition and configuration metrics, together with variables assessing the physical characteristics of the study area, were used. The analysis was performed using seasonal data from the years 2001 and 2006. The seasonal influence was included as a random effect to account for temporal correlations. Together, the fixed and the random factors explain 78% of the variance, whereas the fixed factors alone explain 10%.

Quantification and assessment of changes in ecosystem service in the Three-River Headwaters Region, China as a result of climate variability and land cover change

Journal Articles & Books
December, 2016
China

Rapid and periodic assessment of the impact of land cover change and climate variability on ecosystem services at regional levels is essential to understanding services and sustainability of ecosystems. This study focused on quantifying and assessing the changes in multiple ecosystem services in the Three-River Headwaters Region (TRHR), China in 2000–2012.

Representing composition, spatial structure and management intensity of European agricultural landscapes: A new typology

Journal Articles & Books
December, 2016
Europe

Comprehensive maps that characterize the variation in agricultural landscapes across Europe are lacking. In this paper we present a new Europe-wide, spatially-explicit typology and inventory of the diversity in composition, spatial structure and management intensity of European agricultural landscapes. Agricultural landscape types were characterized at a 1km2 resolution based on Europe-wide datasets that represent land cover, landscape structure and land management intensity.

Analysis of GPS trajectories to assess spatio-temporal differences in grazing patterns and land use preferences of domestic livestock in southwestern Madagascar

Journal Articles & Books
December, 2016
Madagascar

In order to investigate spatial and temporal characteristics of the purely grazing-based livestock husbandry system in southwestern Madagascar, individual animals from 12 cattle and 12 goat herds that were equally distributed across four villages were fitted with GPS tracking collars and their behaviour during pasturing was directly observed to identify seasonal variations in land use and movement patterns along the regional altitude and vegetation gradient.

In Vitro and In Vivo Assessment of Endocrine Disruptive Activity in a Major South African River

Journal Articles & Books
December, 2016
Mozambique
South Africa
Southern Africa

Endocrine-disrupting contaminant (EDC) loads in rivers, and the associated risk to wildlife, may be linked to different anthropogenic stressors occupying river catchments. The aims of this study were to evaluate seasonal and spatial variation in steroid estrogen loads, and (anti)estrogenic and (anti)androgenic activity in a river catchment (upper Olifants River, South Africa), subject to a diversity of anthropogenic impacts. In addition, Mozambique tilapia, Oreochromis mossambicus, was applied as African-endemic sentinel and source of in vivo biomarkers.

Rainfall-induced nutrient losses from manure-fertilized farmland in an alluvial plain

Journal Articles & Books
December, 2016

Nutrient transport and loss in farmlands are affected by factors such as land cover, fertilization, soil type, rainfall, and management practices. We investigated the temporal and spatial changes in macronutrient transport and loss after fertilization and precipitation in manure-fertilized eggplant farmland in an alluvial plain. Upon adding topical fertilizer, concentrations of most nutrients in runoff and groundwater increased, and nitrogen runoff increased from 22.11 to 35.81 kg/ha, although eggplant yield did not increase correspondingly.