Search results for " mappe"

A multi-temporal study of chlorophyll-a concentration in the Albufera lagoon of Valencia, Spain, using Thematic Mapper data

1990

Abstract A multi-temporal study of chlorophyll-a concentration, has been made by means of Landsat-5 Thematic Mapper (TM) band 1 (0·45-0·52μm) in the Albufera of Valencia, a hypertrophic lagoon of shallow depth. The relationship between this parameter and satellite data was set up from in situ measurements and concurrent satellite data obtained in a campaign from 22 July 1985. This relation has been applied to images of different dates by using a simple procedure of correction, which is based on the use of selected surfaces whose ground reflectance is assumed to be constant with time. Good results were obtained and chlorophyll-a concentrations have been determined with an error of 20 per cen…

Mapping Actual Evapotranspiration by Combining Landsat TM and NOAA-AVHRR Images: Application to the Barrax Area, Albacete, Spain

1998

Abstract A method that permits determination of actual evapotranspiration, ET, in heterogeneous areas has been proposed. It is based on the relation ET = ET m − B ( T s − T sm ), which combines meteorological, National Oceanic and Atmospheric Administration advanced very high resolution radiometer (NOAA-AVHRR), and Landsat thematic mapper (TM) data. Thus, the maximum evapotranspiration for each crop, ETm, is obtained from in situ measurements carried out in a meteorological station; the temperature difference between each pixel and the pixel that has the maximum evapotranspiration, Ts−Tsm, is calculated for each crop from NOAA-AVHRR data; and the crop distribution in the area is known throu…

Interannual vineyard crop variability in the Castilla–La Mancha region during the period 1991–1996 with Landsat Thematic Mapper images

2004

The vineyard crop is considered an indicator of vegetation cover processes in the Castilla–La Mancha region, as the crop has undergone far-reaching changes in the last ten years: abandonment, removal of vineyards and replacement with other crops such as cereal. The so-called ‘Change detection’ is a process that allows identification of differences in the state of the vineyard by observing it at different times. Essentially, it involves the ability to quantify temporal effects using multi-temporal datasets. The aim of this study is to analyse the vineyard variability during the period 1991–1996 using different Landsat-5 Thematic Mapper (TM) images belonging to an identified period that highl…

An alternative simple approach to estimate atmospheric correction in multitemporal studies

1989

Abstract Studies that use multitemporal images require the conversion of original digital data into the corresponding physical magnitudes. Atmospheric correction is one of the most important steps in this process, which is usually undertaken using atmospheric radiative transfer models. The main difficulty in these models is the need of atmospheric input data which are not usually available. An alternative approach to atmospheric correction is proposed in this Letter. It is based on the idea that the atmospheric effects over two or more dates can be determined in a relative way, by using the apparent reflectance values of surfaces whose ground reflectance can be considered unchangeable with …

Comment and Reply on “Mapping of serpentinites in the Eastern Desert of Egypt by using Landsat thematic mapper data”

1987

Relationships between climatic parameters and forest vegetation: application to burned area in Alicante (Spain)

2000

Abstract The main aims of this study is to examine the variability of normalized difference vegetation index (NDVI) on forest vegetation in Alicante (Spain) between 1984 and 1994 and to analyse the influence of climatic parameters in the regeneration of forest areas burned by fires. The zone of study is located between XUTM (m) 730400-760400 and YUTM (m) 4274000-4304000 and is characterised by a great topographic complexity that leads to diverse microclimatic conditions. In this area, the maximum annual rainfall of the Valencian Community is recorded, reaching 850 mm of average annual rainfall ( Belda, 1997 ). We examined the spatial and temporal analyse of rainfall and soil moisture over t…

Integrated satellite data fusion and mining for monitoring lake water quality status of the Albufera de Valencia in Spain

2015

Abstract Lake eutrophication is a critical issue in the interplay of water supply, environmental management, and ecosystem conservation. Integrated sensing, monitoring, and modeling for a holistic lake water quality assessment with respect to multiple constituents is in acute need. The aim of this paper is to develop an integrated algorithm for data fusion and mining of satellite remote sensing images to generate daily estimates of some water quality parameters of interest, such as chlorophyll a concentrations and water transparency, to be applied for the assessment of the hypertrophic Albufera de Valencia. The Albufera de Valencia is the largest freshwater lake in Spain, which can often pr…

Accuracy assessment of fraction of vegetation cover and leaf area index estimates from pragmatic methods in a cropland area

2009

The fraction of vegetation cover (FVC) and the leaf area index (LAI) are important parameters for many agronomic, ecological and meteorological applications. Several in-situ and remote sensing techniques for estimating FVC and LAI have been developed in recent years. In this paper, the uncertainty of in-situ FVC and LAI measurements was evaluated by comparing estimates from LAI-2000 and digital hemispherical photography (DHP). The accuracy achieved with a spectral mixture analysis algorithm and two vegetation indices-based methods was assessed using atmospherically corrected Landsat Thematic Mapper (TM) data over the Barrax cropland area where the European Space Agency (ESA) SENtinel-2 and …

A catalog of HLA type, HLA expression, and neo-epitope candidates in human cancer cell lines

2014

Cancer cell lines are a tremendous resource for cancer biology and therapy development. These multipurpose tools are commonly used to examine the genetic origin of cancers, to identify potential novel tumor targets, such as tumor antigens for vaccine devel-opment, and utilized to screen potential therapies in preclinical studies. Mutations, gene expression, and drug sensitivity have been determined for many cell lines using next-generation sequencing (NGS). However, the human leukocyte antigen (HLA) type and HLA expression of tumor cell lines, characterizations necessary for the development of cancer vaccines, have remained largely incomplete and, such information, when available, has been …

Using Landsat TM and field data to produce maps of predicted bird densities in Latvian farmland

2005

Models of farmland bird population densities established from field surveys were applied to classified satellite data for mapping of predicted bird numbers. The field survey system was based upon point counts of birds and descriptions of their habitat within a 200 m radius. The relationship between birds and habitats was analysed by means of multiple regression analysis. The resulting regression models were coded into classified Landsat Enhanced Thematic Mapper (ETM+) data which had similar land cover/use classes as the field observation data. With the use of a circular 200 m radius moving window approach, simulated maps of predicted bird population densities were produced. The results indi…