Pasar al contenido principal

page search

Displaying 817 - 828 of 2218

Hierarchical Community Occurrence Model for North Carolina Stream Fish

Journal Articles & Books
Diciembre, 2014
Estados Unidos de América
América Septentrional

The southeastern USA is home to one of the richest—and most imperiled and threatened—freshwater fish assemblages in North America. For many of these rare and threatened species, conservation efforts are often limited by a lack of data. Drawing on a unique and extensive data set spanning over 20 years, we modeled occurrence probabilities of 126 stream fish species sampled throughout North Carolina, many of which occur more broadly in the southeastern USA.

Modelling snow water equivalent and spring runoff in a boreal watershed, James Bay, Canada

Journal Articles & Books
Diciembre, 2014
Canadá

The hydrology of boreal regions is strongly influenced by seasonal snow accumulation and melt. In this study, we compare simulations of snow water equivalent (SWE) and streamflow by using the hydrological model HYDROTEL with two contrasting approaches for snow modelling: a mixed degree‐day/energy balance model (small number of inputs, but several calibration parameters needed) and the thermodynamic model CROCUS (large number of inputs, but no calibration parameter needed).

Incorporating Risk of Reinvasion to Prioritize Sites for Invasive Species Management

Journal Articles & Books
Diciembre, 2014
Estados Unidos de América
Global

The relationship between landscape pattern and the distribution and spread of exotic species is an important determinant of where and when management actions are best applied. We have developed an interdisciplinary approach for prioritizing treatment of harmful, nonnative, invasive plants in National Park landscapes of the Mid-Atlantic USA.

Badger (Taxidea taxus) Resource Selection and Spatial Ecology in Intensive Agricultural Landscapes

Journal Articles & Books
Diciembre, 2014

American badgers (Taxidea taxus) are a prairie obligate species, but badger resource selection and space use is poorly understood, particularly east of the Mississippi River where anthropogenic land uses have replaced most native prairie. We assessed badger multi-scale resource selection and space use in intensive agricultural areas in Illinois and Ohio. We predicted that badgers would select for pasture and prairie, and higher elevations, and riparian areas because these habitats likely favor burrowing and foraging.

Modelling habitat suitability in the Aquatic Warbler wintering ground Djoudj National Park area in Senegal

Journal Articles & Books
Diciembre, 2014
Senegal

The only well-studied wintering ground of the globally threatened Aquatic Warbler Acrocephalus paludicola is the ‘Djoudj area’ in Senegal. This study identifies potential Aquatic Warbler habitats within that area and gives an estimate of the size of the local wintering population. A land-cover map was generated by classifying high-resolution satellite images. Overlaying it with presence–absence data from field surveys and using logistic regression models (GLMM), we derived the presence probability of the Aquatic Warbler in the study area.

Integrated approach for understanding spatio-temporal changes in forest resource distribution in the central Himalaya

Journal Articles & Books
Diciembre, 2014

Intense anthropogenic exploitation has altered distribution of forest resources. This change was analyzed using visual interpretation of satellite data of 1979, 1999 and 2009. Field and interactive social surveys were conducted to identify spatial trends in forest degradation and data were mapped on forest cover and land use maps. Perceptions of villagers were compiled in a pictorial representation to understand changes in forest resource distribution in central Himalaya from 1970 to 2010. Forested areas were subject to degradation and isolation due to loss of connecting forest stands.

relationships between land cover, climate and cave copepod spatial distribution and suitability along the Carpathians

Journal Articles & Books
Diciembre, 2014

The distribution of subterranean copepods may reflect the persistence of cave assemblages in relation to the environmental health of the overlying landscape. Areas supporting groundwater fauna were established by modelling the persistence of seven copepod species using a geographical information system (GIS). Environmental drivers were found to influence subterranean copepod distribution in the caves of the Romanian Carpathians.

Invasion of an Exotic Shrub into Forested Stands in an Agricultural Matrix

Journal Articles & Books
Diciembre, 2014

We investigated the relative importance of stand and landscape characteristics in the invasion of a nonnative shrub, Amur honeysuckle, in 40 woodlots in an agricultural matrix in southwest Ohio. We quantified stand characteristics that could influence invasibility, the intrinsic susceptibility of an area to invasion, including woodlot size, perimeter-to-area ratio, tree basal area, and stand age.

Implications of uncertainty and scale in carbon emission estimates on locally appropriate designs to reduce emissions from deforestation and degradation (REDD+)

Journal Articles & Books
Diciembre, 2014
Indonesia

This study combined uncertainty analysis of carbon emissions with local stakeholders' perspectives to develop an effective Reducing Emission from Deforestation and Degradation (REDD+) scheme at the district level. Uncertainty of carbon emission estimates depends on scale while local stakeholders' views on plausible REDD+ schemes influence and limit transaction costs. The uncertainty analysis formed the basis for determining an appropriate scale for monitoring carbon emission estimates as performance measures for REDD+ incentives.

Current European corn borer, Ostrinia nubilalis, injury levels in the northeastern United States and the value of Bt field corn

Journal Articles & Books
Diciembre, 2014
Estados Unidos de América

BACKGROUND: Recent evidence indicates that some populations of European corn borer (ECB), Ostrinia nubilalis (Hübner), have declined to historic lows owing to widespread adoption of Bt corn hybrids. To understand current ECB populations in Pennsylvania field corn, the authors assessed larval damage in Bt and non‐Bt corn hybrids at 29 sites over 3 years. The influence of Bt adoption rates, land cover types and moth activity on levels of ECB damage was also considered.

Still a one species genus? Strong genetic diversification in the world’s largest living odonate, the Neotropical damselfly Megaloprepus caerulatus

Journal Articles & Books
Diciembre, 2014

Mesoamerican biodiversity is increasingly threatened by anthropogenic destruction of natural land cover. Habitat degradation and climate change are primary threats to specialized forest odonate species that are important model organisms for forest health and defining conservation units. The extreme niche specialization of Megaloprepus caerulatus, the world’s largest extant odonate, makes it well suited as an indicator for changing environmental conditions.

Factors Associated with Flammulated Owl and Northern Saw-Whet Owl Occupancy in Southern Idaho

Journal Articles & Books
Diciembre, 2014

Spatially explicit models depicting species occupancy offer a useful conservation tool for land managers. Using occurrence data collected in 2009 and 2010 from the Boise National Forest, Idaho, we developed distribution models for Flammulated Owls (Psiloscops flammeolus) and Northern Saw-whet Owls (Aegolius acadicus) to explore associations between habitat factors and owl occupancy. We then spatially applied these models in a Geographic Information System.