Digital terrain models (DTM’s) are widely used in coastal engineering. Reliable height information is necessary for different purposes such as calculating flood risk scenarios, change detection of morphological objects and hydrographic numeric modelling. In this specific field light detection and ranging (lidar) replaces step by step other methods such as terrestrial surveying. However, some ne...

A simple vegetation model for polarimetric covariance and coherency matrix elements is presented. The model aims to represent vegetation characteristics which are observable by radar polarimetry, including the average particle anisotropy, the main orientation of the volume, the degree of orientation randomness in the volume, and the terrain slopes. The decomposition consists, in analogy to the ...

1. introductionhumans have actively managed and transformed the world’s landscapes for millennia. after the industrial revolution (between 1820 and 1840) with increase in sanitation, food security and quality of life the human population increased tremendously. urbanization, the demographic transition from rural to urban, is associated with shifts from an agriculture-based economy to mass indus...

Soil properties are well known to affect vegetation, but the role of soil heterogeneity in the patterning of vegetation dynamics is poorly documented. We asked whether the location of an ecotone separating grass-dominated and sparsely vegetated areas reflected only historical variation in degradation or was related to variation in inherent soil properties. We then asked whether changes in the c...

Generating and visualizing large areas of vegetation that look natural makes terrain surfaces much more realistic. However, this is a challenging field in computer graphics, because ecological systems are complex and visually appealing plant models are geometrically detailed. This work presents Silva (System for the Instantiation of Large Vegetated Areas), a system to generate and visualize lar...

The rapid growth in urban population is seen to create a need for the development of more urban infrastructures. In order to meet this need, natural surfaces such as vegetation are been replaced with non-vegetated surfaces such as asphalt and bricks which has the ability to absorb heat and release it later. This change in land cover is seen to increase the land surface temperature. Previous stu...

land use changes are one of the important consequences of urban spatial extent. regarding the role of green space as one of important land use classes in urban ecosystems, the investigations of its changes seem to be crucial. in this study, to estimate the changes of green space, the ndvi index was applied to tm and irs images of 1990 and 2006 and green space maps of district 1 of tehran munici...

The Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) is one of the most complete and frequently used global-scale DEM products in various applications. However, previous studies have shown that the SRTM DEM is systematically higher than the actual land surface in vegetated mountain areas. The objective of this study is to propose a procedure to calibrate the SRTM DEM over l...