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Changes in the fragmentation and ecological stability of the Morava River floodplain forest in the course of the 20th century

Policy Papers & Briefs
Março, 2009
República Checa

This paper presents the results of an analysis of the changes in the fragmentation and ecological stability of the floodplain forest geobiocoenoses in the Protected Landscape Area Litovelske Pomoravi, Czech Republic. Using GIS methods, it was determined that the fragmentation within the study area had increased slightly and the ecological stability of the landscape had decreased slightly between the years 1938 and 2006, although the latter remained on a fairly high level.

An evaluation of the accuracy of DEM-derived altitude and slope values

Reports & Research
Dezembro, 1995
Colômbia
América Central
América do Sul

This project was set up to investigate the level of accuracy which can be expected for slope and altitude values derived from low-cost Digital Elevation Models (DEMs). Eight gridded DEMs were generated from digitized contour maps at a range of scales:1:10,000 1:25,000 1:100,000 1:200,000 - and using a range of contour intervals 25m, 50m and 100m. A Control DEM was then produced using large scale aerial photographs (1:28,000) which were registered for auto-extraction of z-values using Helava software and accuracy tested using 91 differentially measured GPS ground control points.

An irrigated area map of the world (1999) derived from remote sensing

Reports & Research
Dezembro, 2006

This document summarizes the materials and methods used to create a series of maps of irrigated areas of the world using remote sensing approaches. These maps are complementary to existing statistics (FAO-Aquastat) and the GISderived maps (FAO/University of Frankfurt Global irrigated area map). The document also provides details of how the estimates of global irrigated areas in one main season (net) and more than one season (intensity or annualized) were derived.