Posted on behalf of Todd Wester, Director of Curriculum and Instruction, LPS
July 20, 2010
“Where have all the bugs gone?” Livingston, MT school students aim to find the cause and a solution to the disappearance of a once-diverse and abundant population of stream-bottom dwelling insects, crustaceans, mollusks, flatworms, and segmented worms from Fleshman Creek, an urban stream that flows through their south-central Montana town.
The study of these organisms, typically referred to as benthic macro-invertebrates, constitutes just one aspect of the comprehensive stream study program now offered in elementary, middle, and high school grades in Livingston Public Schools. In addition to tracking biological indicators of water quality, students regularly measure physical parameters such as temperature, flow, stream contour, and turbidity; and chemical parameters, including pH, phosphate and nitrate levels, and dissolved oxygen. For the past two years, high school agriculture and biology students have collected samples for laboratory chemical analysis.
Results indicate that chemical and physical parameters fall within normal limits at the times the measurements were taken; however, the lack of pollution-sensitive benthos in the urban reach of Fleshman reveals the occurrence of low water-quality events there in the recent past. Following a 2007 chemical spill in Fleshman Creek of undetermined origin, benthic macro-invertebrate populations declined dramatically, and have yet to return to historic levels. Typically, recolonization by species such as caddis and mayflies takes place quickly after water quality returns to normal. The continued absence of these organisms may signify repeated events.
New for 2010, students will analyze real-time data transmitted from remote sensing equipment installed in Fleshman Creek. The constant logging of temperature, depth, pH, dissolved oxygen, turbidity and conductivity data may indicate when low water quality events take place, and might provide some clues as to what causes them.
The water quality monitoring program in Livingston Public Schools began nearly two decades ago, and has involved dozens of teachers and hundreds of students. Project-based studies have included annual field trips to Suce Creek, Daly Lake, numerous reaches of Fleshman Creek, and the Yellowstone River. Through comparative sampling, students observe differences in physical, chemical and biological water quality indicators between watersheds and before and after restoration projects.
Today, the program is widespread through Livingston schools, with emphasis at grades 2, 4, 7, and in high school biology and agriculture classes. Younger students participate with mentors from older grades. Second- and fourth-grade students conduct mapping, classification, and identification exercises; at a recent fundraiser, several second-grade students operated a booth wherein they showed visitors how to sort macro-invertebrates according to pollution sensitivity. Seventh grade life science students carry out chemical sampling using kits, collect kick-net samples, label storm drains, and study cause-effect relationships between water quality parameters and effects on stream ecology. High school students collect grab samples for lab analysis, interpret results, and run significant aspects of restoration projects, including riparian management and weed control. A group of high school agriculture students is currently comparing the effects of sheep grazing vs. mechanical controls on weeds along a newly-restored reach of Fleshman.
As extensions of the monitoring program, students have participated in several stream restoration projects, including gathering baseline data and photo points, making recommendations about the engineering of new stream channels, planning and implementing riparian management plans, and labeling storm drains throughout town.
Todd A. Wester
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