Ruptured stream anticline pools as Portage Escarpment habitat features



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Introduction On Cleveland's urbanized Portage Escarpment, small Lake Erie tributary ravines show degraded anthropogenic aquatic habitats. Escarpment ravines also have small geological features called stream anticlines which, when naturally ruptured, produce channel pools that tend to improve habitat. Problem At the base of deep ravines within the local Devonian shale sedimentary sequence, small, non-tectonic stream anticlines are notable upwarp deformation features. As exposed anticline crests naturally rupture and erode, aquatic pools form within the resident stream channel. Watershed scientists assess such pools as healthy habitat features but do not link them with discreet geological process. Synthesizing from both sciences, a significant Portage Escarpment habitat feature type is proposed. Results In the escarpment ravines of Cleveland's urban Heights, flashy stream flows reduce aquatic habitat to scoured bedrock channels and isolated gravel bars. Nevertheless, where ruptured stream anticlines produce channel pools, habitat assessments (HHEI, QHEI) show higher than expected scores. Ruptured anticline features are herein identified for Devonian sedimentary units within the Doan Brook-Frontal Lake Erie administrative watershed. Significant pool habitat features are enumerated. Conclusion In Portage Escarpment ravines, ruptured stream anticline channel pools are underappreciated aquatic habitat features. When appearing in scoured bedrock channels typical of local urban hydrology, such pools can enhance habitat health. With the systematics of anticline pools in hand, escarpment ravine habitat restorations can better build upon local natural conditions. In any event, ruptured anticline pools should be preserved as natural components in aquatic habitat health.