Land use, spatial scale, and stream systems: lessons from an agricultural region.
We synthesized nine studies that examined the influence of land use at different spatial scales in structuring biotic assemblages and stream channel characteristics in southeastern Minnesota streams. Recent studies have disagreed about the relative importance of catchment versus local characteristics in explaining variation in fish assemblages. Our synthesis indicates that both riparian- and catchment-scale land use explained significant variation in water quality, channel morphology, and fish distribution and density. Fish and macroinvertebrate assemblages can be positively affected by increasing the extent of perennial riparian and upland vegetation. Our synthesis is robust; more than 425 stream reaches were examined in an area that includes a portion of three ecoregions. Fishes ranged from coldwater to warmwater adapted. We suggest that efforts to rehabilitate stream system form and function over the long term should focus on increasing perennial vegetation in both riparian areas and uplands and on managing vegetation in large, contiguous blocks.
Vondracek
Bruce
B
U.S. Geological Survey Minnesota Cooperative Fish and Wildlife Research Unit, University of Minnesota, 1980 Folwell Avenue, St. Paul, MN, 55108, USA. bvondrac@umn.edu
Blann
Kristen L
KL
Cox
Carson B
CB
Nerbonne
Julia Frost
JF
Mumford
Karen G
KG
Nerbonne
Brian A
BA
Sovell
Laurie A
LA
Zimmerman
Julie K H
JK
D000383:Agriculture; D000818:Animals; D003247:Conservation of Natural Resources; D017753:Ecosystem; D004777:Environment; D005399:Fishes; D007448:Invertebrates; D008910:Minnesota; D010944:Plants; D045483:Rivers; D014881:Water Supply