Orientation matters: Patch anisotropy controls discharge competence and hydroperiod in a patterned peatland

Abstract

[1] Identifying the mechanisms that drive development of self-organized patterned landscapes is essential for guiding ecosystem management and restoration. In this work, we modeled flow through real and geostatistically simulated landscapes to test the hypothesis that feedbacks between patch anisotropy and hydroperiod may be sufficient to explain development of the flow-parallel ridge-slough mosaic of the Everglades (Florida, USA). Results show patch anisotropy to be a strong predictor of hydroperiod, with ecologically significant increases in flooding duration (>40 days/year) in isotropic landscapes compared with areas of the Everglades with the best-conserved anisotropic patterning. Notably, hydroperiod differences among landscapes were largest in dry years, suggesting that low flow periods may be most influential in landscape pattern development, contrary to alternative models of pattern formation. This study demonstrates the potential for coupled feedbacks between landscape geometry and hydrology to drive anisotropic pattern formation via inundation frequency without requiring velocity-driven erosion and redistribution of particulates. © 2012. American Geophysical Union. All Rights Reserved.