A Methodology to Quantify the Topographic Characteristics of Wetland Landscapes
Loading...
Date
2018-01-19
Authors
Branton, Collin
Journal Title
Journal ISSN
Volume Title
Publisher
University of Waterloo
Abstract
Topography underpins natural processes ranging from incident solar radiation at a location to overland flow and water pooling. Despite the influence of topography on natural processes and subsequent ecosystem function, especially in wetland ecosystems reliant on surrounding topography for water inputs, topography has not been adequately incorporated into reclamation planning and permit closure requirements. Instead, wetland restoration and reclamation projects are typically guided by simple height-to-length ratios that produce little variation or resemblance to natural wetlands. We present a methodology to quantify the topographic characteristics in wetland landscapes to guide the creation of naturally appearing and self-sustaining reclaimed wetland landscapes. Topographic characteristics in 3,434 1km2 sample landscapes were quantified using terrain roughness and landform element composition and configuration. A large set of metrics were reduced to a parsimonious subset that was applied across three natural regions and a gradient of disturbance. Nonparametric statistical tests were used to compare landscapes across these two dimensions. We found that landscape-scale topographic characteristics can be represented by five roughness metrics and seven landform element pattern metrics. These metrics demonstrate that surface roughness and landform element patterns significantly differ among natural regions and that high disturbance landscapes significantly differ from other disturbance levels. Wetland reclamation plans should replicate the topographic characteristics found in the surrounding natural landscape. To do so, topographic characteristic benchmarks are required for reclamation design and regulatory approval of closure permits. The presented methodology and resulting metric values can be used as a step towards achieving this goal.
Description
Keywords
Topography, Terrain Analysis, Reclamation, Wetland Landscapes, GIS