Premium
Use of Stable Isotopes to Trace Municipal Wastewater Effluents into Food Webs within a Highly Developed River System
Author(s) -
Loomer H. A.,
Oakes K. D.,
Schiff S. L.,
Taylor W. D.,
Servos M. R.
Publication year - 2015
Publication title -
river research and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.679
H-Index - 94
eISSN - 1535-1467
pISSN - 1535-1459
DOI - 10.1002/rra.2826
Subject(s) - outfall , effluent , environmental science , δ15n , wastewater , aquatic ecosystem , invertebrate , isotope analysis , food chain , δ13c , estuary , water quality , hydrology (agriculture) , ecology , stable isotope ratio , environmental engineering , biology , geology , physics , geotechnical engineering , quantum mechanics
Many anthropogenic inputs, such as municipal wastewater effluents (MWWEs), affect stable isotope signatures (δ 13 C and δ 15 N) at the base of exposed food webs creating spatial patterns reflecting their incorporation into aquatic food webs. The Grand River in southern Ontario, Canada, is a heavily modified, rapidly urbanizing river that assimilates wastewater from 30 municipal wastewater treatment plants. Stable isotope analysis was applied to resident aquatic invertebrates and fish influenced by three different wastewater outfalls in early, middle, and late summer to determine how values shifted seasonally and with differing effluent quality. There was a slight increase in δ 13 C in both invertebrates and fish in late summer downstream from the three outfalls, but it is difficult to separate effects of the effluents from downstream gradients. Downstream of two of the three outfalls, the δ 15 N tended to increase relative to upstream, while the remaining effluent, of the poorest quality, decreased δ 15 N values of both invertebrates and fish. Spatial trends in stable isotopes became more pronounced as the summer progressed with the greatest between‐site differences occurring in late summer. This study reflects the complex nutrient dynamics associated with MWWE inputs to rivers and contributes to our understanding and application of stable isotope analysis in impacted lotic ecosystems. Copyright © 2014 John Wiley & Sons, Ltd.