Abstract

Stream burial, the rerouting of streams into underground culverts, is common in industrialized and densely populated urban areas. While stream burial is common in urban environments, direct characterization of the within-culvert environment is rare and it is unclear if buried reaches reflect neighboring open reaches regarding habitat, biota, and water chemistry. Additionally, for a buried stream, the entrance and exit of the culvert are abrupt habitat transitions within the stream channel, and it is unknown if these transitions lead to similarly abrupt responses in biotic and abiotic characteristics or if responses are gradual. Quantifying the within-culvert environment and transitions upon entering/ exiting the culvert has rarely been done but can help inform management practices regarding how these systems are impacted and establish a baseline for evaluating daylighting or stream restoration projects. To understand how culverts affect longitudinal biotic and abiotic characteristics of urban streams, we evaluated longitudinal patterns of physical habitat characteristics, stream water physiochemistry, periphyton biomass, and macroinvertebrate density and diversity in two urban streams that included long (>100 m) culvert reaches. Abrupt transitions in a suite of abiotic and biotic variables were observed at the entrances and exits of the culverts whereas some variables showed no response to the culvert presence. Periphyton biomass and macroinvertebrate density were reduced by 98% and 92%, respectively, by culverts in the two streams. Within the culverts, we observed greater water depths (average of 10 cm outside vs 26 cm within the culvert), finer benthic substrate, and diversity of macroinvertebrates was reduced by 50%. Nutrient concentrations, in contrast, showed no response to the presence of a culvert. Within 60-90 m downstream of the culvert exits, most of the measured parameters returned to levels similar to those observed upstream of the culvert, suggesting that the ecosystem impacts of urban culverts, though dramatic, may be spatially constrained. Published by Elsevier B.V.

Keywords

Editor; Sergi Sabater; Urban streams; Buried streams; Transitions; Macroinvertebrates; Substrate; Culverts

Published in

Science of the Total Environment
2022, Volume: 819, article number: 153050
Publisher: ELSEVIER

SLU Authors

• Buffam, Ishi

  • Department of Landscape Architecture, Planning and Management, Swedish University of Agricultural Sciences
    
  • University of Cincinnati

Sustainable Development Goals

Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss
Make cities and human settlements inclusive, safe, resilient and sustainable


UKÄ Subject classification

Ecology
Landscape Architecture


Publication identifier

DOI: https://doi.org/10.1016/j.scitotenv.2022.153050

Permanent link to this page (URI)

https://res.slu.se/id/publ/116555