Author(s): L. E. Bertassello; P. S. C. Rao; A. F. Aubeneau
Linked Author(s):
Keywords: DEM analysis; Fractal Dimension; Probability Density Function; Size distribution; Wetland Identification
Abstract: Wetlands are ubiquitous topographic depressions on landscapes and form critical elements of the mosaic of aquatic habitats. The role of wetlands in the global hydrological and biogeochemical cycles is intimately tied to their geometric characteristics. We used DEM analysis and local search algorithms to identify wetland attributes (maximum stage, surface area and storage volume) in four wetlandscapes across the United States. We then derived the exceedance cumulative density functions (cdfs) of these attributes for the identified wetlands, applied the concept of fractal dimension to investigate the variability in wetland’shapes. Exponentially tempered Pareto distributions were fitted to DEM derived wetland attributes. In particular, the scaling exponents appear to remain constant through the progressive water-filling of the landscapes, suggesting self-similarity of wetland geometrical attributes. This tendency is also reproduced by the fractal dimension (D) of wetland shorelines, which remains constant across different water-filling levels. In addition, the variability in D is constrained within a narrow range (1< D< 1.33) in all the four wetlandscapes. Finally, the comparison between wetlands identified by the DEM-based model are consistent with actual data.
Year: 2018