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Issuescouverture du solLandLibrary Resource
There are 2, 238 content items of different types and languages related to couverture du sol on the Land Portal.

couverture du sol

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Landscape effects on large scale abundance patterns of turtle doves Streptopelia turtur in Portugal

Journal Articles & Books
Décembre, 2013
Portugal

The European turtle dove is both a highly valued game species and a species of conservation concern, which is declining due probably to a combination of habitat degradation and unsustainable hunting. Although declines seem to be less severe in the Mediterranean region, it remains uncertain the extent to which ongoing land use changes will negatively affect this species. This study examined this issue, by estimating the effects of landscape composition on the broad scale abundance pattern of breeding turtle doves in continental Portugal.

Cover Estimations Using Object-Based Image Analysis Rule Sets Developed Across Multiple Scales in Pinyon-Juniper Woodlands

Journal Articles & Books
Décembre, 2014

Numerous studies have been conducted that evaluate the utility of remote sensing for monitoring and assessing vegetation and ground cover to support land management decisions and complement ground measurements. However, few comparisons have been made that evaluate the utility of object-based image analysis (OBIA) to accurately classify a landscape where rule sets (models) have been developed at various scales. In this study, OBIA rule sets used to estimate land cover from high–spatial resolution imagery (0.06-m pixel) on Pinus L. (pinyon) and Juniperus L.

Stability of environmental reference conditions as indicated by stream macroinvertebrate communities: a case study in the central United States

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

We examined macroinvertebrate community data from Missouri reference streams collected approximately 12 years apart to evaluate whether substantial changes in community metrics and/or taxonomic composition occurred over that period. We used analysis of variance to test whether metrics differed between years or between other variables and used non-metric multidimensional scaling to examine compositional differences among samples and the environmental variables that were most associated with these differences.

Managing landscape heterogeneity in different socio-ecological contexts: contrasting cases from central Loess Plateau of China and southern Finland

Journal Articles & Books
Décembre, 2015
Finlande
Chine

CONTEXT: Landscape transition drives environmental change across the globe. However, landscape and its change are complex with high spatial heterogeneity, which challenges strategic decision-making. OBJECTIVES: This paper aims to derive management meaningful units based on landscape status and change analysis and the generalization of landscape spatial heterogeneity. METHODS: Based on contrasting cases from Finland (Vanajavesi) and China (Baota District), this paper analyzed the landscape attributes and change since 2000.

Effect of Forward/Inverse Model Asymmetries Over Retrieved Soil Moisture Assessed With an OSSE for the Aquarius/SAC-D Mission

Journal Articles & Books
Décembre, 2014

An Observing System Simulation Experiment (OSSE) for the Aquarius/SAC-D mission that includes different models for forward and retrieval processes is presented. This OSSE is implemented to study the errors related to the use of simple retrieval models in passive microwave applications. To this end, a theoretical forward model was introduced, which is suitable to reproduce some of the complexities related to canopy vegetation scattering.

Monitoring Spatial and Temporal Land Use/Cover Changes; a Case Study in Western Black Sea Region of Turkey

Journal Articles & Books
Décembre, 2013
Turquie

Rapid land use/land cover changes have taken place in many cities of Turkey. Land use and land cover changes are essential for wide range of applications. In this study, Landsat TM satellite imageries date from 1987, 1993, 2000 and 2010 were used to analyse temporal and spatial changes in the Western Black Sea Region of Turkey. Zonguldak and Eregli two largest and economic important cities which have been active coal mining and iron fabric areas.

Changing hydrologic connectivity due to permafrost thaw in the lower Liard River valley, NWT, Canada

Journal Articles & Books
Décembre, 2014
Canada

Flows from river basins in northwestern Canada have been rising in the last two decades as a result of climate warming. In the wetland‐dominated basins that characterise the southern margin of permafrost, permafrost thaw and disappearance, and resulting land‐cover change, is occurring at an unprecedented rate. The impact of this thaw on runoff generation in headwater basins is poorly understood.

Spatio‐Temporal Patterns of Land Use/Cover Changes Over the Past 20 Years in the Middle Reaches of the Tarim River, Xinjiang, China

Journal Articles & Books
Décembre, 2015
Chine

The interaction between land use/cover change and landscape pattern is pivotal in research concerning global environmental change. This study uses three different Landsat images of 1989, 1998 and 2009 to study the land use/cover and landscape pattern changes in the middle reaches of the Tarim River basin. envi®, erdas®, ArcGIS® and fragstats® software were used to analyse the land use/cover changes. The objectives of study were to map and study the changes in land use/cover and landscape pattern, and propose some possible factors in making the land use/cover changes from 1989 to 2009.

Variogram Fractal Dimension Based Features for Hyperspectral Data Dimensionality Reduction

Journal Articles & Books
Décembre, 2013

In this paper a new approach for fractal based dimensionality reduction of hyperspectral data has been proposed. The features have been generated by multiplying variogram fractal dimension value with spectral energy. Fractal dimension bears the information related to the shape or characteristic of the spectral response curves and the spectral energy bears the information related to class separation.

Dealing with vagueness in complex forest landscapes: A soft classification approach through a niche-based distribution model

Journal Articles & Books
Décembre, 2011

The increasing interest in biodiversity conservation has led to the development of new approaches to facilitate ecologically based conservation policies and management plans. In this context, the development of effective methods for the classification of forest types constitutes a crucial issue as forests represent the most widespread vegetation structure and play a key role in ecosystem functioning. In this study a maximum entropy approach (Maxent) to forest type classification in a complex Mediterranean area, has been investigated.

Hydrology under change: an evaluation protocol to investigate how hydrological models deal with changing catchments

Journal Articles & Books
Décembre, 2015
Suède

Testing hydrological models under changing conditions is essential to evaluate their ability to cope with changing catchments and their suitability for impact studies. With this perspective in mind, a workshop dedicated to this issue was held at the 2013 General Assembly of the International Association of Hydrological Sciences (IAHS) in Göteborg, Sweden, in July 2013, during which the results of a common testing experiment were presented.