HR: 14:15h
AN: NB23A-04    [Abstracts]
TI: Increased Use of No-till Cropping Systems Improves Stream Ecosystem Quality
AU: * Yates, A G
EM: ayates@uwo.ca
AF: Department of Biology, University of Western Ontario , London, ON N6A 5B7 Canada
AU: Bailey, R C
EM: Drbob@uwo.ca
AF: Department of Biology, University of Western Ontario , London, ON N6A 5B7 Canada
AU: Schwindt, J A
EM: schwindtj@thamesriver.on.ca
AF: Department of Biology, University of Western Ontario , London, ON N6A 5B7 Canada
AB: Release of sediments to streams from tilled lands has been a significant stressor to streams in agro-ecosystems for decades and has been shown to impact aquatic biota in a variety of ways. To limit soil erosion from cultivated lands, conservation tillage techniques, including the use of no-till systems, have been developed and widely adopted throughout the region. However, there haves been no tests of the effects of no-till systems on stream quality at a watershed scale. We measured habitat and water quality and sampled the benthic macroinvertebrate (BMI) and fish communities in 32 small (100-1400 ha) subwatersheds along a gradient of the proportion of land under no-till cropping systems to determine relationships between the use of no-till and stream quality. Our results demonstrate that with increasing proportions of no-till, habitat scores improve, the quantities of sediment and sediment associated stressors in the water decline, the BMI community exhibits reduced dominance by Oligocheata and Sphaeriidae, as well as improved Family Biotic Index (FBI) scores, and fish species richness increases. We concluded that increased use of no-till cropping systems by farmers does contribute to improved quality of streams in agro-ecosystems.
DE: 9820 Techniques applicable in three or more fields
DE: 9902 NABS Student Award Applied Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly