Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


Diesburg_Thesis_Final.pdf (6.32 MB)

ETD Abstract Container

Abstract Header

Consequences of terrestrial invaders for aquatic-riparian linkages

Diesburg, Kristen M
http://orcid.org/0000-0002-0346-0251
http://rave.ohiolink.edu/etdc/view?acc_num=osu1619139419375299

Abstract Details

2021, Doctor of Philosophy, Ohio State University, Environment and Natural Resources.
Biological invasions threaten biodiversity and ecosystem functions. Stream ecosystems and their adjacent riparian zones are connected via a complex network of direct and indirect linkages, presenting a unique setting for the study of invasion. I investigated the effects of two different riparian invaders on stream biota and stream-riparian trophic linkages: an invasive insect (hemlock woolly adelgid Adelges tsugae; hereafter HWA) and an invasive shrub (bush honeysuckles Lonicera maackii and L. tatarica). Both sets of studies used the same basic approach at >20 streams across a gradient of invasion intensity: record geomorphology and water chemistry, collect and assess in-stream biota, quantify reciprocal subsidies, and determine riparian spider density, relative reliance on aquatically-derived energy (i.e., nutritional subsidies originating from periphyton), and invertebrate food-chain length (using naturally-abundant stable isotopes) at each study reach. I also conducted a before-after, control-impact (BACI design) honeysuckle removal experiment. My results suggest that in-stream physical and chemical alterations (i.e., large-wood characteristics and nutrient concentrations) associated with HWA invasion and subsequent hemlock decline drove changes in stream invertebrate diversity and trophic relationships. Evidence for ecological consequences of this invader was strongest at lower trophic levels. For example, periphyton biomass was greater at uninvaded reference sites than at severely invaded sites (x̅ = 1.37 vs 0.52 mg cm-2), while relative abundance of herbivorous macroinvertebrates increased from 4 to 23% at the severely invaded sites. Spider (family Tetragnathidae) densities were 3.2 times higher at sites with severe hemlock decline and although density was not linked to emergent insect density overall, δ15N signatures of Araneidae and Pisauridae spider families tracked emergent insect δ15N (r2 = 0.42 and 0.78, respectively), suggesting a trophic linkage. Although honeysuckle density was related to lower relative abundance of herbivorous and small-bodied invertebrates (r2 = 0.46 and 0.39, respectively), it was a poor predictor of the benthic invertebrate community overall in both the observational and experimental portions of this study. Rather, I found that land use (i.e., impervious surface) and/or bankfull width (which incorporates both stream size and channel instability) were implicated as negative and positive drivers, respectively, of invertebrate density, diversity, and the relative abundance of the orders Ephemeroptera, Plecoptera, and Trichoptera. Honeysuckle presence was, however, associated with a lower reliance on aquatically-derived energy by tetragnathid spiders (r2 = 0.52), and trended with reductions in invertebrate food-chain length (r2 = 0.15; p = 0.051). In both studies, I demonstrate that riparian invaders in widely different settings influence stream-riparian trophic linkages. My work highlights the usefulness of a food-web approach and the importance of reach- and watershed-scale variables in describing impacts of biological invasions on stream-riparian structure and function. Understanding these interactions will improve our ability to manage invasive species and riparian zones, especially in a linked-ecosystem context.
S. Mazeika Sullivan (Advisor)
Lauren Pintor (Committee Member)
P. Charles Goebel (Committee Member)
324 p.
Ecology; Environmental Science; Freshwater Ecology
aquatic insects; aquatic-terrestrial linkages; invasive species; stream ecosystems; water chemistry; Hemlock woolly adelgid Adelges tsugae, subsidies, orb-weaving spiders, isotopes, emergence, stream; Amur honeysuckle Lonicera maackii

Recommended Citations

Citations

  • Diesburg, K. M. (2021). Consequences of terrestrial invaders for aquatic-riparian linkages [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1619139419375299

    APA Style (7th edition)

  • Diesburg, Kristen. Consequences of terrestrial invaders for aquatic-riparian linkages. 2021. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1619139419375299.

    MLA Style (8th edition)

  • Diesburg, Kristen. "Consequences of terrestrial invaders for aquatic-riparian linkages." Doctoral dissertation, Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1619139419375299

    Chicago Manual of Style (17th edition)

osu1619139419375299
80
© 2021, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.