Improved stream food web function associated with stream simulation design culverts in northern Great Lakes streams
Typical goals of aquatic organism passage projects include providing adequate passage of aquatic organisms and rarely consider whether stream food web function is improved. We examined differences in habitat and food web responses (periphyton, organic matter, and invertebrates) in upstream, downstream, and culvert reaches at paired road-stream crossings in northern Wisconsin streams located within the Chequamegon-Nicolet National Forest. One culvert of each pair was constructed using the Stream Simulation Design (SSD) which mimics natural channel structure, while the other was left to fill on its own (non-SSD). Habitat characteristics within SSD crossings included shallower depths, faster velocities, and substrate dominated by cobble, pebble, and gravel, while silt dominated non-SSD crossings. Periphyton standing crop was greater in SSD crossings than non-SSD crossings. Fine benthic organic matter was significantly greater at non-SSD crossings than at all other reaches. Standing crops of coarse organic matter food resources (leaves/wood) and invertebrate abundances were significantly lower at non-SSD crossings compared to upstream and downstream reaches. Collector-gatherer chironomids dominated invertebrate communities at non-SSD crossings, while mayflies, stoneflies, and caddisflies dominated reaches at SSD sites. Food webs at SSD road-stream crossings more closely reflected reference reaches demonstrating that SSD can provide ecological functions beyond aquatic organism passage.
Minnesota Lake Superior Watershed Stream Science Symposium
Eggert, S. L.,
King, N. R.,
Improved stream food web function associated with stream simulation design culverts in northern Great Lakes streams.
Minnesota Lake Superior Watershed Stream Science Symposium,
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