Portland State University PDXScholar Dissertations and Theses Dissertations and Theses Spring 6-6-2014 Macroinvertebrates and Excessive Fine Sediment Conditions in Oregon Coastal Streams Patrick Michael Edwards Portland State University Follow this and additional works at: https://pdxscholar.library.pdx.edu/open_access_etds Part of the Fresh Water Studies Commons, and the Sedimentology Commons Let us know how access to this document benefits ou.y Recommended Citation Edwards, Patrick Michael, "Macroinvertebrates and Excessive Fine Sediment Conditions in Oregon Coastal Streams" (2014). Dissertations and Theses. Paper 1831. https://doi.org/10.15760/etd.1830 This Dissertation is brought to you for free and open access. It has been accepted for inclusion in Dissertations and Theses by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. Macroinvertebrates and Excessive Fine Sediment Conditions in Oregon Coastal Streams by Patrick Michael Edwards A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Environmental Sciences and Resources Dissertation Committee: Yangdong Pan, Chair Ian Waite Heejun Chang Sherri Johnson Alan Yeakley Portland State University 2014 i Abstract The Pacific Coastal ecoregion contains large tracts of economically important forestlands that also serve as critical stream habitat for endangered Salmonids. Excessive fine sediment deposition in streams of this region is a major environmental concern in the region but difficult to measure directly. The use of stream invertebrates to monitor fine sediment conditions in streams requires careful consideration of several important factors that complicate their use as bioindicators including high spatial and temporal variability and covariance with other environmental variables. To evaluate the use of stream invertebrates as bioindicators of excessive fine sediment, three hypotheses were tested. The first hypothesis was that invertebrates would be related to broad-scale climate variables (Chapter 2). The second hypothesis was that functional aspects of the invertebrate community would serve as useful indicators of excessive fine sediment condition. (Chapter 3). The third hypothesis was that invertebrates in streams with naturally high levels of sediment would be tolerant to fine sediment (<2 mm, Chapter 4). Hypotheses were tested using a temporal data set at two streams in western Oregon, spatial data from 214 sites across the Oregon Coast Range, and in-situ experiment conducted in streams with erosive or resistant geologies. In the temporal study, both invertebrate density and functional traits were positively related to El Niño strength (R2 range = 0.22-0.36, ρ range = 0.008-0.04) and air temperature (R2 range = 0.32-0.49, ρ range = 0.002-0.01). The spatial study identified several environmental and hydrological factors that exhibited strong negative controls on both fine sediment (Mantel r range 0.14-0.25, ρ range = 0.001-0.01) and invertebrate i Scrapers (R2 range = 0.11-0.14, ρ range = 0.001-0.04). The result of the experimental study provide evidence that invertebrates in streams with erosive geologies exhibit tolerance to sediment addition when compared to invertebrates in resistant geologies (mean loss=15%, ρ <0.01) and that invertebrate grazing traits were most strongly associated with fine sediment dosing frequency (ρ <0.05). The findings of this research demonstrate the role of geology in shaping invertebrate communities and their functional response to fine sediment addition and identify functional indicators that may be useful in different geologic settings. For environmental managers in the Pacific Coastal ecoregion, these findings are of potential value in assisting with the identification of biologically-relevant changes in stream fine sediment conditions and support efforts to balance economic needs in the region while protecting critical Salmonid habitat. ii Acknowledgements Many thanks to my advisor, Dr. Yangdong Pan. Dr. Pan provided thoughtful advice and support through every step of my degree. I would also like to thank my committee members: Dr. Heejun Chang, Dr. Sherri Johnson, Dr. Ian Waite and Dr. Alan Yeakley, all of whom provided many insightful suggestions and advice about my research. The Oregon Department of Environmental Quality provided me the data for Chapter 3 and Shannon Hubler was always happy to answer questions and give helpful advice about the data. I would also like to thank the graduate students of Dr. Pan’s lab. Without their help, I could not have finished this work. I’m also grateful for the financial support I have received from Portland State University and the Cascades to Coast GK-12 Program. Data and facilities were provided by the HJ Andrews Experimental Forest research program, funded by the National Science Foundation's Long-Term Ecological Research Program (DEB 0823380), US Forest Service Pacific Northwest Research Station, and Oregon State University. And finally, I’d like to thank my family and friends for their encouragement and support. iii Table of Contents Abstract ................................................................................................................................i Acknowledgements ............................................................................................................iii List of Tables .................................................................................................................... vi List of Figures ..................................................................................................................viii Chapter 1: Introduction .......................................................................................................1 SEDIMENT POLLUTION OF SMALL STREAMS IN THE UNITED STATES ...........1 THE OREGON COAST RANGE STUDY AREA ............................................................3 FINE SEDIMENT DYNAMICS IN OREGON COAST RANGE STREAMS .................3 ECOLOGICAL FRAMEWORK ........................................................................................4 ABIOTIC AND BIOTIC CONTROLS OF INVERTEBRATE ASSEMBLAGE IN STREAMS...........................................................................................................................4 HIERARCHICAL CONTROLS OF INVERTEBRATE ASSEMBLAGE.........................6 BIOME LEVEL ..................................................................................................................6 BASIN LEVEL ...................................................................................................................8 REACH LEVEL ...............................................................................................................10 PATCH LEVEL ................................................................................................................13 LITERATURE SYNTHESIS AND GAP ANALYSIS ....................................................15 IMPACT OF EXCESSIVE FINE SEDIMENT ON INVERTEBRATE...........................15 MECHANISMS OF FINE SEDIMENT IMPACTS ON INVERTEBRATES AT MULTIPLE SCALES .......................................................................................................16 INVERTEBRATE MOUTHPARTS AS INDICATORS OF EXCESSIVE FINE SEDIMENT IN STREAMS ..............................................................................................19 GAP IN THE LITERATURE ...........................................................................................22 Chapter 2: Stream Invertebrate and Climate Relationships in the Pacific Coastal Ecoregion of Oregon .........................................................................................................31 ABSTRACT ......................................................................................................................31 INTRODUCTION ............................................................................................................32 METHODS .......................................................................................................................35 iv RESULTS .........................................................................................................................41 DISCUSSION ...................................................................................................................44 Chapter 3: Invertebrate Indicators of Excessive Fine Sediment in Streams of the Oregon Coast Range ......................................................................................................................67 ABSTRACT ......................................................................................................................67 INTRODUCTION ............................................................................................................68 METHODS .......................................................................................................................72 RESULTS .........................................................................................................................78 DISCUSSION ...................................................................................................................84 Chapter 4: An in-situ experiment to test the effect of natural sediment supply on stream invertebrate response to fine sediment addition in naturally colonized mesocosms ......103 ABSTRACT ....................................................................................................................103