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Accounting for tree line shift, glacier retreat and primary succession in mountain plant distribution models

Journal Articles & Books
December, 2014

AIM: To incorporate changes in alpine land cover (tree line shift, glacier retreat and primary succession) into species distribution model (SDM) predictions for a selection of 31 high‐elevation plants. LOCATION: Chamonix Valley, French Alps. METHODS: We fit linear mixed effects (LME) models to historical changes in forest and glacier cover and projected these trends forward to align with 21st century IPCC climate scenarios. We used a logistic function to model the probability of plant establishment in glacial forelands zones expected to become ice free between 2008 and 2051–2080.

Effects of seasonal variation and land cover on riparian denitrification along a mid-sized river

Journal Articles & Books
December, 2014
United States of America

Urban areas contribute disproportional nitrogen (N) loads to downstream aquatic ecosystems resulting in potential hypoxic ‘dead’ zones. Riparian areas along streams and rivers reduce inorganic N concentrations through denitrification, an anaerobic microbial process. Our study objective was to investigate the denitrification potential of riparian areas with differing land cover composition along the Licking River in Kentucky, USA – a tributary of the Ohio River. For one year we collected monthly samples from four sites along a 60 km reach of the Licking River.

Influence of catchment land cover on stoichiometry and stable isotope compositions of basal resources and macroinvertebrate consumers in headwater streams

Journal Articles & Books
December, 2014

Anthropogenic land use affects aquatic landscapes. For example, landscape-level conversion to urban or agricultural land can heavily influence nutrient cycles in headwater streams via increased nutrient loading and altered hydrologic patterns. Recent studies in headwater streams have found that the stoichiometry and stable isotope compositions of basal resources and consumers can vary as a result of landscape-level change.

Land fragmentation and variation of ecosystem services in the context of rapid urbanization: the case of Taizhou city, China

Journal Articles & Books
December, 2014
China

This study analyzes land use dynamics, land fragmentation, variation of ecosystem service value (ESV), and the underlying driving forces in the context of rapid urbanization in Taizhou city, China. An integrated approach utilizing geographic information system and remote sensing was used to analyze land use/land cover change, spatiotemporal patterns of land fragmentation and variation of ESV over the period of 1995–2010.

Object-Based Image Analysis of Pinyon and Juniper Woodlands Treated to Reduce Fuels

Journal Articles & Books
December, 2014

Mechanical and prescribed fire treatments are commonly used to reduce fuel loads and maintain or restore sagebrush steppe rangelands across the Great Basin where pinyon (Pinus) and juniper (Juniperus) trees are encroaching and infilling. Geospatial technologies, particularly remote sensing, could potentially be used in these ecosystems to (1) evaluate the longevity of fuel reduction treatments, (2) provide data for planning and designing future fuel-reduction treatments, and (3) assess the spatial distribution of horizontal fuel structure following fuel-reduction treatments.

Raptor Presence Along an Urban–Wildland Gradient: Influences of Prey Abundance and Land Cover

Journal Articles & Books
December, 2014

Native animals are affected differently by urbanization. Some species respond favorably and thrive in human-dominated landscapes, but others are extirpated. Raptors are often sensitive to changes in land cover and prey abundance. We therefore used a combination of broadcast surveys and incidental observations while spot-mapping to evaluate the influences of these two variables on the presence of raptors at 21 sites from 2004–2008 along an urban-to-wildland gradient in western Washington, U.S.A.

Distribution, Morphometry, and Land Use of Delmarva Bays

Journal Articles & Books
December, 2014
United States of America

Delmarva Bays are depressional wetlands that are elliptical in shape with sandy rims, and occur mainly in the central portion of the Delmarva Peninsula within the Mid- Atlantic United States. Situated in a region with abundant agriculture, Delmarva Bays and other wetlands may enhance water quality by reducing nutrient and sediment levels in local waters. A significant portion have been drained and converted from forested wetlands to agriculture.

effect of forest fire on mass movement in Lebanese mountainous areas

Journal Articles & Books
December, 2014
Lebanon

Mass movements are major hazards that threaten natural and human environments. In Lebanon, the occurrence of mass movements increased by almost 60% between 1956 and 2008. Forest fire has emerged as an additional hazard: it destroyed over 25% of Lebanon’s forests in a period less than 40 years. This paper investigates the potential effect of forest fire on the occurrence of mass movements in the Damour and Nahr Ibrahim watersheds of Lebanon. Mass movement and forest fire inventory maps were produced through remote sensing using aerial and satellite images.

Monitoring dynamic changes of global land cover types: fluctuations of major lakes in China every 8� days during 2000–2010

Journal Articles & Books
December, 2014
China

Remote sensing images can be used to delineate variations in the area of lakes and to assess the influence of environmental changes and human activities. However, because lakes are dynamic, results obtained from individual images acquired on a single date are not representative and do not accurately reflect ongoing changes. In this study, we used 8-day moderate resolution imaging spectroradiometer (MODIS) composite data from 2000 to 2010 to map water surface changes over 629 lakes in China.

Can trait‐based analyses of changes in species distribution be transferred to new geographic areas?

Journal Articles & Books
December, 2014
Belgium

AIM: Anthropogenic environmental change is having a major impact on biodiversity. By identifying traits that correlate with changes in species range, comparative studies can shed light on the mechanisms driving this change; but such studies will be more useful for conservation if they have true predictive power, i.e. if their trait‐based models can be transferred to new regions. We aim to examine the ability of trait‐based models to predict changes in plant distribution across seven geographic regions that varied in terms of land cover and species composition.

global 1‐km consensus land‐cover product for biodiversity and ecosystem modelling

Journal Articles & Books
December, 2014
Antarctica

AIM: For many applications in biodiversity and ecology, existing remote sensing‐derived land‐cover products have limitations due to among‐product inconsistency and their typically non‐continuous nature. Here we aim to help address these shortcomings by generating a 1‐km resolution global product that provides scale‐integrated and accuracy‐weighted consensus land‐cover information on an approximately continuous scale. LOCATION: Global. METHODS: Using a generalized classification scheme and an accuracy‐based integration approach, we integrated four global land‐cover products.

GIS based mapping of land cover changes utilizing multi-temporal remotely sensed image data in Lake Hawassa Watershed, Ethiopia

Journal Articles & Books
December, 2014
Ethiopia

Classifying multi-temporal image data to produce thematic maps and quantify land cover changes is one of the most common applications of remote sensing. Mapping land cover changes at the regional level is essential for a wide range of applications including land use planning, decision making, land cover database generation, and as a source of information for sustainable management of natural resources.