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Issuescobertura do soloLandLibrary Resource
There are 2, 240 content items of different types and languages related to cobertura do solo on the Land Portal.

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Object-oriented classification of land use/cover using digital aerial orthophotography

Journal Articles & Books
Dezembro, 2012

In automatic/semiautomatic mapping of land use/cover using very high resolution remote-sensing imagery, the major challenge is that a single class of land use contains ground targets with varied spectral values, textures, geometries and spatial features. Here we present an object-oriented strategy for automatic/semiautomatic classifications of land use/cover using very high resolution remote-sensing data. The strategy consists of character detecting, object positioning and coarse classification, then refining the classification result step by step.

Soil inorganic carbon storage pattern in China

Journal Articles & Books
Dezembro, 2008
China

Soils with pedogenic carbonate cover about 30% (3.44 x 10⁶ km²) of China, mainly across its arid and semiarid regions in the Northwest. Based on the second national soil survey (1979-1992), total soil inorganic carbon (SIC) storage in China was estimated to be 53.3±6.3 PgC (1 Pg=10¹⁵ g) to the depth investigated to 2 m. Soil inorganic carbon storages were 4.6, 10.6, 11.1, and 20.8 Pg for the depth ranges of 0-0.1, 0.1-0.3, 0.3-0.5, and 0.5-1 m, respectively. Stocks for 0.1, 0.3, 0.5, and 1 m of depth accounted for 8.7%, 28.7%, 49.6%, and 88.9% of total SIC, respectively.

Clarity versus complexity: Land-use modeling as a practical tool for decision-makers

Journal Articles & Books
Dezembro, 2013

The last decade has seen a remarkable increase in the number of modeling tools available to examine future land-use and land-cover (LULC) change. Integrated modeling frameworks, agent-based models, cellular automata approaches, and other modeling techniques have substantially improved the representation of complex LULC systems, with each method using a different strategy to address complexity. However, despite the development of new and better modeling tools, the use of these tools is limited for actual planning, decision-making, or policy-making purposes.

Local Wood Demand, Land Cover Change and the State of Albany Thicket on an Urban Commonage in the Eastern Cape, South Africa

Journal Articles & Books
Dezembro, 2015
África do Sul
África austral

Understanding the rates and causes of land-use change is crucial in identifying solutions, especially in sensitive landscapes and ecosystems, as well as in places undergoing rapid political, socioeconomic or ecological change. Despite considerable concern at the rate of transformation and degradation of the biodiversity-rich Albany Thicket biome in South Africa, most knowledge is gleaned from private commercial lands and state conservation areas.

Spatial distribution of ultrafine particles in urban settings: A land use regression model

Journal Articles & Books
Dezembro, 2012
Espanha

BACKGROUND: The toxic effects of ultrafine particles (UFP) are a public health concern. However, epidemiological studies on the long term effects of UFP are limited due to lacking exposure models. Given the high spatial variation of UFP, the assignment of exposure levels in epidemiological studies requires a fine spatial scale. The aim of this study was to assess the performance of a short-term measurement protocol used at a large number of locations to derive a land use regression (LUR) model of the spatial variation of UFP in Girona, Spain.

Modelling trace metal background to evaluate anthropogenic contamination in arable soils of south-western France

Journal Articles & Books
Dezembro, 2013
França

The trace metal (TM) content in arable soils has been monitored across a region of France characterised by a large proportion of calcareous soils. Within this particular geological context, the objectives were to first determine the natural levels of trace metals in the soils and secondly, to assess which sites were significantly contaminated. Because no universal contamination assessment method is currently available, four different methods were applied and compared in order to facilitate the best diagnosis of contamination.

Integrating remotely sensed data, GIS and expert knowledge to update object-based land use/land cover information

Journal Articles & Books
Dezembro, 2012

Remote-sensing technology provides a powerful means for land use/land cover (LU/LC) monitoring at global and regional scales. However, it is more efficient and effective to combine remote-sensing measurements with a geographic information system (GIS) database and expert knowledge for change updating than to use remote-sensing technology alone. In this article, these different sources of information are integrated in the proposed framework, which is able to provide rapid updating of LU/LC information.

Dimensões humanas do uso e cobertura das terras na Amazônia: uma contribuição do LBA

Journal Articles & Books
Dezembro, 2005

An understanding of changes in Amazonian landscapes depends on documentation about alterations in land cover. This article highlights the efforts of the Large Scale Biosphere-Atmosphere Experiment in Amazônia (LBA) related to the topic. In particular, a longitudinal study has analyzed the social and biophysical dimensions of land use/land cover, using a multi-scalar georeferenced approach. The study areas represent a gradient of soil fertility in Amazônia and include distinct landscape mosaics, from the Amazon estuary and the Bragantina region to northeastern Rondônia.

Spatial distribution of greenhouse gas concentrations in arid and semi-arid regions: A case study in East Asia

Journal Articles & Books
Dezembro, 2013
China
Mongólia
Ásia Oriental

Land degradation and global warming are currently highly active research topics. Land degradation can both change land cover and surface climate and significantly influence atmospheric circulation. Researches have verified that carbon dioxide (CO₂) and methane (CH₄) are major greenhouse gases (GHG) in the atmosphere and are directly affected by human activity. However, to date, there is no research on the spatial distribution of GHG concentrations and also no research on how land degradations affect GHG concentrations in arid and semi-arid regions.

Streamflow regimes of the Yanhe River under climate and land use change, Loess Plateau, China

Journal Articles & Books
Dezembro, 2015
China

Soil and water conservation measures including terracing, afforestation, construction of sediment‐trapping dams, and the ‘Grain for Green Program’ have been extensively implemented in the Yanhe River watershed, of the Loess Plateau, China, over the last six decades, and have resulted in large‐scale land use and land cover changes. This study examined the trends and shifts in streamflow regime over the period of 1953–2010 and relates them to changes in land use and soil and water conservation and to the climatic factors of precipitation and air temperature.

Vegetation and climate of Anatolia and adjacent regions during the Last Glacial period

Journal Articles & Books
Dezembro, 2013

Reinterpretation of vegetation and climatic conditions of Anatolia and neighboring regions during Last Glacial (30–15 cal ka BP) have been done using a non-quantitative biomization approach based on previously published plant functional types. The results suggest that the climate was cold and humid before ∼25 cal ka BP and also during the period ∼23–19 cal ka BP (except East Anatolia). Forest vegetation was 80–90% of the land cover in the northwestern Anatolia and Black Sea coast, and 50–60% along the Mediterranean coast at the same period.

Introduced annual grass increases regional fire activity across the arid western USA (1980–2009)

Journal Articles & Books
Dezembro, 2013
Estados Unidos

Non‐native, invasive grasses have been linked to altered grass‐fire cycles worldwide. Although a few studies have quantified resulting changes in fire activity at local scales, and many have speculated about larger scales, regional alterations to fire regimes remain poorly documented. We assessed the influence of large‐scale Bromus tectorum (hereafter cheatgrass) invasion on fire size, duration, spread rate, and interannual variability in comparison to other prominent land cover classes across the Great Basin, USA.