Martin Kappas

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Losses of biodiversity and ecosystem functioning due to rainforest destruction and agricultural intensification are prime concerns for science and society alike. Potentially, ecosystems show nonlinear responses to land-use intensification that would open management options with limited ecological losses but satisfying economic gains. However,(More)
In this work a new gap-fill technique entitled projection transformation has been developed and used for filling missed parts of remotely sensed imagery. In general techniques for filling missed area of an image are broken down into three main categories: multi-source techniques that take the advantages of other data sources (e.g. using cloud free images to(More)
The tropical rain forests in Indonesia are affected by socio-economic and ecological factors and processes that result in an increasing destabilisation of the rainforest margins. Optical satellite data have been explored to document changes in land cover throughout the past 30 years and to monitor the current status and dynamics of land cover and land cover(More)
The Landsat-7 Enhanced Thematic Mapper Plus (ETM+) is the sensor payload on the Landsat-7 satellite imager (launched on April 15th, 1999) that is a derivative of the Landsat-4 and 5 Thematic Mapper (TM) land imager sensors. Scan Line Corrector (SLC) malfunctioning appeared onboard on May 31, 2003. The SLC-Off problem was caused by failure of the SLC which(More)
BACKGROUND Deep vein thrombosis (DVT) is a common problem in clinical practice causing severe complications. In this retrospective study, the distribution and extent of DVT in the lower limb in symptomatic patients were evaluated. Certain risk factors were also investigated. METHODS The venograms of 187 symptomatic individuals (postoperative, medical, and(More)
Carbon sequestration was estimated in a semi-arid grassland region in Central Kazakhstan using an approach that integrates remote sensing, field measurements and meteorological data. Carbon fluxes for each pixel of 1 × 1 km were calculated as a product of photosynthetically active radiation (PAR) and its fraction absorbed by vegetation (fPAR), the light use(More)
A new multi-decade national-wide coarse-resolution data set of leaf area index (LAI) over the Republic of Kazakhstan has been developed based on data from the Advanced Very High Resolution Radiometer (AVHRR) and in situ measurements of vegetation structure. The Kazakhstan-wide LAI product has been retrieved using an algorithm based on a physical radiative(More)
The study investigates the vulnerability of vegetation over Africa to El-Niño Southern Oscillation (ENSO) events using the moving window statistical correlation analysis technique. The correlation analysis was done betweenNormalized Difference Vegetation Index (NDVI) data fromAdvanced VeryHigh Resolution Radiometer (AVHRR) and an ENSO index, namely(More)