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Development of a GIS-based failure investigation system for highway soil slopes

Journal Articles & Books
Dezembro, 2015

A framework for preparation of an early warning system was developed for Maryland, using a GIS database and a collective overlay of maps that highlight highway slopes susceptible to soil slides or slope failures in advance through spatial and statistical analysis. Data for existing soil slope failures was collected from geotechnical reports and field visits. A total of 48 slope failures were recorded and analyzed. Six factors, including event precipitation, geological formation, land cover, slope history, slope angle, and elevation were considered to affect highway soil slope stability.

Assessing the impact of urbanization on net primary productivity using multi-scale remote sensing data: a case study of Xuzhou, China

Journal Articles & Books
Dezembro, 2015
China

An improved Carnegie Ames Stanford Approach (CASA) model based on two kinds of remote sensing (RS) data, Landsat Enhanced Thematic Mapper Plus (ETM +) and Moderate Resolution Imaging Spectro-radiometer (MODIS), and climate variables were applied to estimate the Net Primary Productivity (NPP) of Xuzhou in June of each year from 2001 to 2010. The NPP of the study area decreased as the spatial scale increased. The average NPP of terrestrial vegetation in Xuzhou showed a decreasing trend in recent years, likely due to changes in climate and environment.

Effects of land cover conversion on soil properties and soil microbial activity in an alpine meadow on the Tibetan Plateau

Journal Articles & Books
Dezembro, 2015
China

Land cover conversion intensively occurred in the Tibetan Plateau of China during the past decades. However, responses of soil properties and soil microbial activities to land cover conversion under different land cover types have not been fully understood. The objective was to assess the effects of land cover conversion on soil C and N stocks and soil microbial properties of topsoil of an alpine meadow in the Tibetan Plateau. Soil cores of surface soil (0–20 cm) were collected from three adjacent land cover types: native alpine meadow, artificial grassland and mound-shaped denuded land.

Landscape Prediction and Mapping of Game Fish Biomass, an Ecosystem Service of Michigan Rivers

Journal Articles & Books
Dezembro, 2015

The increased integration of ecosystem service concepts into natural resource management places renewed emphasis on prediction and mapping of fish biomass as a major provisioning service of rivers. The goals of this study were to predict and map patterns of fish biomass as a proxy for the availability of catchable fish for anglers in rivers and to identify the strongest landscape constraints on fish productivity.

Implications of genetics and current protected areas for conservation of 5 endangered primates in China

Journal Articles & Books
Dezembro, 2015
China

Most of China's 24–28 primate species are threatened with extinction. Habitat reduction and fragmentation are perhaps the greatest threats. We used published data from a conservation genetics study of 5 endangered primates in China (Rhinopithecus roxellana, R. bieti, R. brelichi, Trachypithecus francoisi, and T. leucocephalus); distribution data on these species; and the distribution, area, and location of protected areas to inform conservation strategies for these primates. All 5 species were separated into subpopulations with unique genetic components.

Hydrologic changes resulting from urban cover in seasonally snow‐covered catchments

Journal Articles & Books
Dezembro, 2015
Canadá

There are few multibasin analyses of the effects of urban land cover on seasonal stream flow patterns within northern watersheds where winter snow cover is the norm. In this study, the effects of urban cover on stream flow were evaluated at nine catchments in southern Ontario, Canada, which vary greatly in urban impervious cover (1–84%) but cluster into two groups having ≥54% urban impervious area (‘urban’) and ≤11% impervious cover (‘rural’), respectively.

Anticipated climate and land‐cover changes reveal refuge areas for Borneo's orang‐utans

Journal Articles & Books
Dezembro, 2015

Habitat loss and climate change pose a double jeopardy for many threatened taxa, making the identification of optimal habitat for the future a conservation priority. Using a case study of the endangered Bornean orang‐utan, we identify environmental refuges by integrating bioclimatic models with projected deforestation and oil‐palm agriculture suitability from the 1950s to 2080s. We coupled a maximum entropy algorithm with information on habitat needs to predict suitable habitat for the present day and 1950s.

Landslide susceptibility mapping along Kolli hills Ghat road section (India) using frequency ratio, relative effect and fuzzy logic models

Journal Articles & Books
Dezembro, 2015
Índia

This article emphasizes landslide susceptibility mapping along Ghat road of Kolli hills, Tamil Nadu, India, using frequency ratio, relative effect and fuzzy gamma operator models with the help of remote sensing data and GIS technique. The purpose of the study is to generate, compare and validate landslide susceptibility zones. Landslide inventory was done with data collected from the State Highways department.

Land cover recognition using min-cut/max-flow segmentation and orthoimages

Conference Papers & Reports
Dezembro, 2015
Letónia

The geospatial information is significant for many socio-technical activities like urban planning, the prediction of natural hazards, the monitoring of land use, weather forecasting, cadastral surveys etc. It is possible to acquire geospatial information from a distance using remote sensing technologies, but remotely sensed images don’t have semantics without a previous recognition. The classification of geospatial information is expensive and time consuming process. The paper describes the automatic land cover recognition method, which is based on min-cut/max-flow segmentation.

High-resolution maps of forest-urban watersheds present an opportunity for ecologists and managers

Journal Articles & Books
Dezembro, 2015
Estados Unidos

CONTEXT: Green infrastructure may improve water quality and mitigate flooding in forest-urban watersheds, but reliably quantifying all benefits is challenging because most land cover maps depend on moderate- to low-resolution data. Complex and spatially heterogeneous landscapes that typify forest-urban watersheds are not fully represented with these types of data. Hence important questions concerning how green infrastructure influences water quality and quantity at different spatial scales remain unanswered.

What are hot and what are not in an urban landscape: quantifying and explaining the land surface temperature pattern in Beijing, China

Journal Articles & Books
Dezembro, 2015
China

CONTEXT: Understanding how landscape components affect the urban heat islands is crucial for urban ecological planning and sustainable development. OBJECTIVE: The purpose of this study was to quantify the spatial pattern of land surface temperatures (LSTs) and associated heat fluxes in relation to land-cover types in Beijing, China, using portable infrared thermometers, thermal infrared imagers, and the moderate resolution imaging spectroradiometer.

Assessing bundles of ecosystem services from regional to landscape scale: insights from the French Alps

Journal Articles & Books
Dezembro, 2015

Assessments of ecosystem services (ES) and biodiversity (hereafter ecological parameters) provide a comprehensive view of the links between landscapes, ecosystem functioning and human well‐being. The investigation of consistent associations between ecological parameters, called bundles, and of their links to landscape composition and structure is essential to inform management and policy, yet it is still in its infancy.