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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.

cobertura do solo

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Impact of sample size allocation when using stratified random sampling to estimate accuracy and area of land-cover change

Journal Articles & Books
Dezembro, 2012

The ground reference data obtained to assess map accuracy can be simultaneously used to estimate area (extent). This dual-purpose use of ground reference data is examined for the special case of a two-class map of ‘change’ and ‘no change’. To assess the accuracy of a change map, stratified sampling is often implemented with a disproportionately larger sample size allocated to the map change stratum. But this allocation targeting user's accuracy of change is not necessarily effective for the competing objective of estimating the area of change.

Land cover in Upper Egypt assessed using regional and global land-cover products derived from MODIS imagery

Journal Articles & Books
Dezembro, 2012

Irrigation along the Nile River has resulted in dramatic changes in the biophysical environment of Upper Egypt. In this study we used a combination of Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m Normalized Difference Vegetation Index data and Landsat imagery to identify areas that changed from 2001 to 2008 as a result of irrigation and water-level fluctuations in the Nile River and nearby waterbodies.

Impact of reference datasets and autocorrelation on classification accuracy

Journal Articles & Books
Dezembro, 2011
Estados Unidos

Reference data and accuracy assessments via error matrices build the foundation for measuring success of classifications. An error matrix is often based on the traditional holdout method that utilizes only one training/test dataset. If the training/test dataset does not fully represent the variability in a population, accuracy may be over – or under – estimated. Furthermore, reference data may be flawed by spatial errors or autocorrelation that may lead to overoptimistic results.

Phenological dynamics of irrigated and natural drylands in Central Asia before and after the USSR collapse

Journal Articles & Books
Dezembro, 2012
Turquemenistão
Usbequistão
Ásia
Ásia Central

Central Asia has experienced drastic socio-economic, geopolitical, and ecological transitions within the last few decades. The USSR collapse in 1991 has led to widespread changes in land cover and land use due to economic and political transformations within the region. Management practices during and after the Soviet era have intensified ecological problems and demands on resources.

Earthquake-induced landslide mapping in the western Himalayas using medium resolution ASTER imagery

Journal Articles & Books
Dezembro, 2011
Paquistão

On 8 October 2005, a devastating earthquake struck northern Pakistan and several parts of Pakistani- and Indian-controlled Kashmir. The severely hit areas lie in close proximity to the most tectonically active region of the western Himalayas. The earthquake destroyed close to 400 000 houses and over 75 000 people lost their lives. The intensity of the earthquake was such that it triggered widespread landslides, which caused considerable destruction of the area's forests, and blocked the mountain roads and rivers.

Assessing the conservation value of a human-dominated island landscape: Plant diversity in Hawaii

Journal Articles & Books
Dezembro, 2008

The conversion of native habitats to pasture and other working lands, unbuilt lands modified by humans for production, is one of the greatest threats to biodiversity. While some human-dominated landscapes on continents support relatively high native biodiversity, this capacity is little studied in oceanic island systems characterized by high endemism and vulnerability to invasion.

Monitoring forest changes in Borneo on a yearly basis by an object-based change detection algorithm using SPOT-VEGETATION time series

Journal Articles & Books
Dezembro, 2012

Monitoring land cover over large areas on a yearly basis is challenging. The spatial and temporal consistency of an object-based change detection algorithm was tested through a multi-year application on the forest of Borneo, using SPOT-VEGETATION time series from 2000 to 2008. Continuous change thresholds allowed the tuning of the algorithm according to specific requirements in terms of omission and commission errors.

Effects of land cover on runoff coefficient

Journal Articles & Books
Dezembro, 2011
Tailândia

Land cover is considered to have significant influence on the hydrologic response of a river basin. In this study, we assessed how changes in land cover over time affected flood behaviour from 1988 to 2005, in the Upper Ping River Basin, northern Thailand. We correlated the types of land cover with rainfall–runoff behaviour for smaller and larger flood events taking place during this period. To quantify land cover, nine Landsat 5 TM images taken during the dry season (January or February) were obtained and processed to examine inter-annual land cover changes.

Improving 30 m global land-cover map FROM-GLC with time series MODIS and auxiliary data sets: a segmentation-based approach

Journal Articles & Books
Dezembro, 2013

FROM-GLC (Fine Resolution Observation and Monitoring of Global Land Cover) is the first 30 m resolution global land-cover map produced using Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data. Due to the lack of temporal features as inputs in producing FROM-GLC, considerable confusion exists among land-cover types (e.g. agriculture lands, grasslands, shrublands, and bareland). The Moderate Resolution Imaging Spectrometer (MODIS) provides high-temporal frequency information on surface cover.

Soil panning by drive systems of agricultural machines

Policy Papers & Briefs
Dezembro, 2010
Bielorrússia

The results of the field research studying the effects of aggregates with heavy payload machines on the soil are presented. The influence of maximum tire pressure on soil while changing the pressure in a wide range is analyzed. The main characteristics of the machines, such as total mass; running gear load level; tire air pressure; maximal pressure on soil; soil density and the dip of the machine's track are shown. The experiment has been made on different soil types. Changes of relative strain of loose and solid sandy clay are displayed.

multi-modeling approach to evaluating climate and land use change impacts in a Great Lakes River Basin

Journal Articles & Books
Dezembro, 2010

River ecosystems are driven by linked physical, chemical, and biological subsystems, which operate over different temporal and spatial domains. This complexity increases uncertainty in ecological forecasts, and impedes preparation for the ecological consequences of climate change. We describe a recently developed “multi-modeling” system for ecological forecasting in a 7600 km² watershed in the North American Great Lakes Basin.

Climate Change and Agricultural Development: Adapting Polish Agriculture to Reduce Future Nutrient Loads in a Coastal Watershed

Journal Articles & Books
Dezembro, 2014
Polônia

Currently, there is a major concern about the future of nutrient loads discharged into the Baltic Sea from Polish rivers because they are main contributors to its eutrophication. To date, no watershed-scale studies have properly addressed this issue. This paper fills this gap by using a scenario-modeling framework applied in the Reda watershed, a small (482� km²) agricultural coastal area in northern Poland. We used the SWAT model to quantify the effects of future climate, land cover, and management changes under multiple scenarios up to the 2050s.