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Issuescouverture du solLandLibrary Resource
There are 2, 240 content items of different types and languages related to couverture du sol on the Land Portal.

couverture du sol

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

Journal Articles & Books
Décembre, 2014
Chine

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.

Simulation of runoff and nutrient export from a typical small watershed in China using the Hydrological Simulation Program–Fortran

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

The Hydrological Simulation Program-Fortran (HSPF), which is a hydrological and water-quality computer model that was developed by the United States Environmental Protection Agency, was employed to simulate runoff and nutrient export from a typical small watershed in a hilly eastern monsoon region of China. First, a parameter sensitivity analysis was performed to assess how changes in the model parameters affect runoff and nutrient export. Next, the model was calibrated and validated using measured runoff and nutrient concentration data.

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

Journal Articles & Books
Décembre, 2014
États-Unis d'Amérique

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.

Spectral mixture analysis for bi-sensor wetland mapping using Landsat TM and Terra MODIS data

Journal Articles & Books
Décembre, 2012
États-Unis d'Amérique
Chine

Spatial and temporal resolution is essential for understanding the spatial and temporal characteristics and dynamics of wetland ecosystems. However, single satellite imagery with both high spatial resolution and high temporal frequency is currently unavailable. Instead, the development of a bi-sensor monitoring technique utilizing spatial details of middle-to-high resolution data and temporal details of coarse spatial resolution data is highly desirable.

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

Journal Articles & Books
Décembre, 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.

Fragmentation of forest communities in the eastern United States

Journal Articles & Books
Décembre, 2012
États-Unis d'Amérique

Forest fragmentation threatens the sustainability of forest communities in the eastern United States. Forest communities exhibiting either a low total area or low percentage of intact forest are subject to relatively higher risk of shifts in stand composition towards edge-adapted and invasive species. Such changes in stand composition could result in local extirpation of communities, homogenization of forest communities at broader spatial scales, and a consequential reduction of the biodiversity values of forestland.

Assessing ecological integrity: A multi-scale structural and functional approach using Structural Equation Modeling

Journal Articles & Books
Décembre, 2016
Canada

Facing increasing levels of ecosystem degradation, scientists and practitioners aim to preserve ecological integrity — to maintain structures and functions expected of ecosystems in a region. This requires an understanding of the relationship between structural components and functional integrity. In this paper we focused on the study forests of the Credit River Watershed (Southern Ontario, Canada).

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

Journal Articles & Books
Décembre, 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.

From the redwood forest to the Gulf Stream waters: human signature nearly ubiquitous in representative US landscapes

Journal Articles & Books
Décembre, 2010
États-Unis d'Amérique

What landscapes best represent the land uses and land covers (LU/LC) of the continental United States? Would the set include a cornfield? A forest? A backyard? Combining principles of landscape ecology and computer science, we identified a small set of “exemplar landscapes”, representing distinct LU/LC pattern types of the conterminous US. We first partitioned the 1992 US National Land Cover Dataset into 193 705 landscapes, and quantified patterns with standard measures of LU/LC composition and configuration.

Successional and seasonal variations in soil and litter microbial community structure and function during tropical postagricultural forest regeneration: a multiyear study

Journal Articles & Books
Décembre, 2015
Porto Rico

Soil microorganisms regulate fundamental biochemical processes in plant litter decomposition and soil organic matter (SOM) transformations. Understanding how microbial communities respond to changes in vegetation is critical for improving predictions of how land‐cover change affects belowground carbon storage and nutrient availability.

Understanding Human–Coyote Encounters in Urban Ecosystems Using Citizen Science Data: What Do Socioeconomics Tell Us?

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

The coyote (Canis latrans) has dramatically expanded its range to include the cities and suburbs of the western US and those of the Eastern Seaboard. Highly adaptable, this newcomer’s success causes conflicts with residents, necessitating research to understand the distribution of coyotes in urban landscapes. Citizen science can be a powerful approach toward this aim.

Distribution, Morphometry, and Land Use of Delmarva Bays

Journal Articles & Books
Décembre, 2014
États-Unis d'Amérique

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.