Passar para o conteúdo principal

page search

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

AGROVOC URI:

Displaying 1753 - 1764 of 1964

Land-cover classification of an intra-urban environment using high-resolution images and object-based image analysis

Journal Articles & Books
Dezembro, 2012
Brasil

Detailed, up-to-date information on intra-urban land cover is important for urban planning and management. Differentiation between permeable and impermeable land, for instance, provides data for surface run-off estimates and flood prevention, whereas identification of vegetated areas enables studies of urban micro-climates. In place of maps, high-resolution images, such as those from the satellites IKONOS II, Quickbird, Orbview and WorldView II, can be used after processing.

Variation in NDVI values with change in spatial resolution for semi-arid savanna vegetation: a case study in northwestern South Africa

Journal Articles & Books
Dezembro, 2013
África do Sul
África austral

Natural vegetation and crop-greening patterns in semi-arid savannas are commonly monitored using normalized difference vegetation index (NDVI) values from low spatial resolution sensors such as the Advanced Very High Resolution Radiometer (AVHRR) (1 km, 4 km) and Moderate Resolution Imaging Spectroradiometer (MODIS) (250 m, 500 m). However, because semi-arid savannas characteristically have scattered tree cover, the NDVI values at low spatial resolution suffer from the effect of aggregation of near-infrared and red energy from adjacent vegetated and non-vegetated cover types.

Estimating Spatial Variability in Atmospheric Properties over Remotely Sensed Land Surface Conditions

Journal Articles & Books
Dezembro, 2008

This paper investigates the spatial relationships between surface fluxes and near-surface atmospheric properties (AP), and the potential errors in flux estimation due to homogeneous atmospheric inputs over heterogeneous landscapes. A large-eddy simulation (LES) model is coupled to a surface energy balance scheme with remotely sensed surface temperature Ts as a key boundary condition. Simulations were performed for different agricultural regions having major contrasts in Ts, canopy cover, and surface rough- ness z0 between vegetated/irrigated and bare soil areas.

Is cellular automata algorithm able to predict the future dynamical shifts of tree species in Italy under climate change scenarios? A methodological approach

Journal Articles & Books
Dezembro, 2011
Itália

In this paper is presented a methodological approach which integrates statistic modelling and 2-D cellular automata (CA) in order to describe tree species shifts responding to the climate changes foreseen for Italy in the 21st century. Five Italian tree species populations of Abies alba, Pinus sylvestris, Fagus sylvatica, Acer campestris and Quercus suber and their actual potential distributions (PDs) – represented by Importance Value (IV), have been considered.

Evaluating Source Area Contributions from Aircraft Flux Measurements Over Heterogeneous Land Using Large-Eddy Simulation

Journal Articles & Books
Dezembro, 2013

The estimation of spatial patterns in surface fluxes from aircraft observations poses several challenges in the presence of heterogeneous land cover. In particular, the effects of turbulence on scalar transport and the different behaviour of passive (e.g. water vapour) versus active (e.g. temperature) scalars may lead to large uncertainties in the source area/flux- footprint estimation for sensible (H) and latent (LE) heat-flux fields.

Assessment of sediment connectivity from vegetation cover and topography using remotely sensed data in a dryland catchment in the Spanish Pyrenees

Journal Articles & Books
Dezembro, 2014

PURPOSE: Many Mediterranean drylands are characterized by strong erosion in headwater catchments, where connectivity processes play an important role in the redistribution of water and sediments. Sediment connectivity describes the ease with which sediment can move through a catchment. The spatial and temporal characterization of connectivity patterns in a catchment enables the estimation of sediment contribution and transfer paths. Apart from topography, vegetation cover is one of the main factors driving sediment connectivity.

Surface energy fluxes over El Reno, Oklahoma, using high-resolution remotely sensed data

Journal Articles & Books
Dezembro, 2003

Accurate estimation of spatial distributions of evapotranspiration (ET) is a goal sought by hydrologists, agronomists, and meteorologists but is difficult to achieve. The usual approaches to estimating ET employ remote sensing observations and a surface energy flux model. However, resolution of remote sensing data, needed to observe patterns of biophysical variables, is commonly too coarse (>1 km) to distinguish between land cover types that constrain ET. Accuracy of ET estimates can be improved by using higher- resolution (

Long term analysis of PALS soil moisture campaign measurements for global soil moisture algorithm development

Journal Articles & Books
Dezembro, 2012

An important component of satellite-based soil moisture algorithm development and validation is the comparison of coincident remote sensing and in situ observations that are typically provided by intensive field campaigns. The planned NASA Soil Moisture Active Passive (SMAP) mission has unique requirements compared to previous soil moisture satellite programs because both active and passive microwave observations are needed. The primary source of these combined observations has been an aircraft-based SMAP simulator called PALS (Passive and Active L-band System).

remote sensing approach to monitor the conservation status of lacustrine Phragmites australis beds

Journal Articles & Books
Dezembro, 2013
Itália

Phragmites australis populations in native areas have been gradually declining since the mid-20th century. We developed a logical approach based on remote sensing to monitor the conservation status of P. australis beds in response to environmental gradients and orient future management actions in Lake Garda (northern Italy). During the 2010 growing season we collected data on: (i) the structural and functional status of seven P.

Water Scarcity in the Andes: A Comparison of Local Perceptions and Observed Climate, Land Use and Socioeconomic Changes

Journal Articles & Books
Dezembro, 2013
Colômbia
América do Sul

In the Andean region of South America, understanding communities’ water perceptions is particularly important for water management as many rural communities must decide by themselves if and how they will protect their micro-watersheds and distribute their water. In this study we examine how Water User Associations in the Eastern Andes of Colombia perceive water scarcity and the relationship between this perception and observed climate, land use, and demographic changes. Results demonstrate a complex relationship between perceptions and observed changes.

Evaluation of ecosystem health for the coastal wetlands at the Yangtze Estuary, Shanghai

Journal Articles & Books
Dezembro, 2013
China

Despite the growing awareness of the important ecological functions and values provided by coastal and estuarine wetlands, wetland degradation continues worldwide due to increasing anthropogenic disturbances. Chongming Dongtan wetlands, adjacent to Shanghai, the largest city and industrial and trading port in China in rapid urban expansion and socioeconomic development are currently threatened with biodiversity reduction, wetland loss, contamination, and invasion of exotic plant.

Happiness is greater in natural environments

Journal Articles & Books
Dezembro, 2013

Links between wellbeing and environmental factors are of growing interest in psychology, health, conservation, economics, and more widely. There is limited evidence that green or natural environments are positive for physical and mental health and wellbeing. We present a new and unique primary research study exploring the relationship between momentary subjective wellbeing (SWB) and individuals’ immediate environment within the UK.