Macroinvertebrate communities in agriculturally impacted southern Illinois streams: patterns with riparian vegetation, water quality, and in-stream habitat quality

• Published in: Journal of environmental quality Vol. 34; no. 3; pp. 907 - 917
• Main Authors: Stone, M.L, Whiles, M.R, Webber, J.A, Williard, K.W.J, Reeve, J.D
• Format: Journal Article
• Language: English
• Published: Madison American Society of Agronomy, Crop Science Society of America, Soil Science Society 01.05.2005; Crop Science Society of America; American Society of Agronomy
• Subjects: agricultural land; Agriculture; Agronomy. Soil science and plant productions; Animals; Applied sciences; Biological and medical sciences; Biomass; Chironomidae; Copepoda; Creeks & streams; Ditches; drainage channels; Drainage ditches; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring; Environmental quality; Exact sciences and technology; Freshwater; Fundamental and applied biological sciences. Psychology; Habitats; Harbors; Illinois; indicator species; Insects; Invertebrates; Macroinvertebrates; Mollusca; Mollusks; Oligochaeta; Organic matter; Physella; Pollution; Pollution, environment geology; population density; Population Dynamics; rapid bioassessment; Riparian ecology; Riparian forests; Riparian land; Riparian vegetation; Rivers; Sphaerium; Streams; Trees; Water - chemistry; Water Pollutants; water pollution; Water quality; Illinois; United States; North America; America; United States > US; USA, Illinois; Chironomidae; Forests; Organic matter; Harbor; Insecta; Biomass; Multiple regression; Crustacea; Surveillance; Riparian; Arthropoda; Surface water; Water quality; Vegetation; Copepoda; Silt; Stream; Invertebrata; Diptera
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq2004.0305

Relationships between riparian land cover, in-stream habitat, water chemistry, and macroinvertebrates were examined in headwater streams draining an agricultural region of Illinois. Macroinvertebrates and organic matter were collected monthly for one year from three intensively monitored streams with a gradient of riparian forest cover (6, 22, and 31% of riparian area). Bioassessments and physical habitat analyses were also performed in these three streams and 12 other nearby headwater streams. The intensively monitored site with the least riparian forest cover had significantly greater percent silt substrates than the sites with medium and high forest cover, and significantly higher very fine organics in substrates than the medium and high forested sites. Macroinvertebrates were abundant in all streams, but communities reflected degraded conditions; noninsect groups, mostly oligochaetes and copepods, dominated density and oligochaetes and mollusks, mostly Sphaerium and Physella, dominated biomass. Of insects, dipterans, mostly Chironomidae, dominated density and dipterans and coleopterans were important contributors to biomass. Collector-gatherers dominated functional structure in all three intensively monitored sites, indicating that functional structure metrics may not be appropriate for assessing these systems. The intensively monitored site with lowest riparian forest cover had significantly greater macroinvertebrate density and biomass, but lowest insect density and biomass. Density and biomass of active collector-filterers (mostly Sphaerium) decreased with increasing riparian forest. Hilsenhoff scores from all 15 sites were significantly correlated with in-stream habitat scores, percent riparian forest, and orthophosphate concentrations, and multiple regression indicated that in-stream habitat was the primary factor influencing biotic integrity. Our results show that these "drainage ditches" harbor abundant macroinvertebrates that are typical of degraded conditions, but that they can reflect gradients of conditions in and around these streams.