Browsing by Author "Cianciolo, Thomas R."

Now showing 1 - 6 of 6
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    Assessing Flow-driven Effects on Local and Downstream Water Quality in Central Appalachian Headwater Streams Influenced by Surface Coal Mining
    Schoenholtz, Stephen H.; McLaughlin, Daniel L.; Entrekin, Sally A.; Hotchkiss, Erin R.; Timpano, Anthony J.; Cianciolo, Thomas R.; Word, Clayton S. (Virginia Tech. Powell River Project, 2020-10)
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    Comparison of benthic macroinvertebrate assessment methods along a salinity gradient in headwater streams
    Pence, Rachel A.; Cianciolo, Thomas R.; Drover, Damion R.; McLaughlin, Daniel L.; Soucek, David J.; Timpano, Anthony J.; Zipper, Carl E.; Schoenholtz, Stephen H. (Springer, 2021-12-01)
    Benthic macroinvertebrate community assessments are used commonly to characterize aquatic systems and increasingly for identifying their impairment caused by myriad stressors. Yet sampling and enumeration methods vary, and research is needed to compare their abilities to detect macroinvertebrate community responses to specific water quality variables. A common assessment method, rapid bioassessment, uses subsampling procedures to identify a fixed number of individual organisms regardless of total sample abundance. In contrast, full-enumeration assessments typically allow for expanded community characterization resulting from higher numbers of identified organisms within a collected sample. Here, we compared these two sampling and enumeration methods and their abilities to detect benthic macroinvertebrate response to freshwater salinization, a common stressor of streams worldwide. We applied both methods in headwater streams along a salinity gradient within the coal-mining region of central Appalachia USA. Metrics of taxonomic richness, community composition, and trophic function differed between the methods, yet most metrics exhibiting significant response to SC for full-enumeration samples also did for rapid bioassessment samples. However, full-enumeration yielded taxonomic-based metrics consistently more responsive to the salinization gradient. Full-enumeration assessments may potentially provide more complete characterization of macroinvertebrate communities and their response to increased salinization, whereas the more cost-effective and widely employed rapid bioassessment method can detect community alterations along the full salinity gradient. These findings can inform decisions regarding such tradeoffs for assessments of freshwater salinization in headwater streams and highlight the need for similar research of sampling and enumeration methodology in other aquatic systems and for other stressors.
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    Hydrologic variability in black ash wetlands: Implications for vulnerability to emerald ash borer
    Cianciolo, Thomas R.; Diamond, Jacob S.; McLaughlin, Daniel L.; Slesak, Robert A.; D'Amato, Anthony W.; Palik, Brian J. (Wiley, 2021-04)
    Black ash (Fraxinus nigra) wetlands are widespread, forested landscape features in the western Great Lakes region. However, the future of these ecosystems is threatened due to impending spread of the invasive emerald ash borer (EAB), which results in tree mortality, decreased transpiration, and potential shifts to wetter, non-forested conditions. The vulnerability to such ecohydrologic shifts likely varies according to local hydrologic regimes controlled by landscape settings, but this site-dependent vulnerability and our ability to predict it is unknown. Here, we assessed vulnerability potential as a function of site hydrology in 15 undisturbed black ash wetlands from their three most common hydrogeomorphic settings in northern Minnesota: lowland, depression, and transition. Further, we used high-resolution (1-cm) surface elevation models to assess spatial variability of water levels at a subset of 10 sites. Although we observed similar ET and groundwater exchange rates among settings, lowland sites were generally drier because of elevated landscape position and greater water level drawdowns (via lower specific yield). We predict that such drier sites will exhibit greater water level increases following EAB-induced ash mortality, compared to wetter sites where open water evaporation and shallow-rooted understory transpiration will offset losses in tree transpiration. Moreover, compared to wetter sites, drier sites exhibited minimal microtopographic variation, limiting the number of elevated microsites for tree establishment and eventual canopy recovery after ash loss. These results suggest that site wetness is a simple and effective predictor of black ash wetland vulnerability to hydrologic regime change. To that end, we assessed the ability of common terrain metrics to predict site wetness, providing a potential tool to target vulnerable areas for active management efforts.
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    Long-term Trends in Specific Conductance, Dissolved Ion Matrix, and Benthic Macroinvertebrate Communities in Central Appalachian Coalfield Streams
    Cianciolo, Thomas R.; Schoenholtz, Stephen H.; McLaughlin, Daniel L. (Virginia Tech. Powell River Project, 2018-08-24)
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    Spatiotemporal Trends in Water Chemistry and Benthic Macroinvertebrates of Headwater Streams Influenced by Surface Coal Mining in Central Appalachia
    Cianciolo, Thomas R.; Schoenholtz, Stephen H.; McLaughlin, Daniel L. (Virginia Tech. Powell River Project, 2019-08-16)
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    Temporal and longitudinal extent of surface coal mining influences on water quality and benthic macroinvertebrate communities in central Appalachian headwater streams
    Cianciolo, Thomas R. (Virginia Tech, 2019-06-18)
    Increased loading of dissolved ions (salinization) and trace elements from surface coal mining is a common alteration to headwater streams in the central Appalachian region. However, temporal and spatial trends of water quality and associated influences on biota in these stream systems have not been well-studied. To address this research need, I analyzed temporal trends in specific conductance, ion matrix, and benthic macroinvertebrate communities in 24 headwater streams, including 19 influenced by surface mining, from 2011-2019. There was limited evidence of recovery of water chemistry or macroinvertebrate communities in these streams, indicating lasting impacts from surface coal mining. Among benthic macroinvertebrates, Ephemeroptera and the scraper functional feeding group were most-impacted by chronic salinization in study streams. In addition, I analyzed spatial patterns of water chemistry in a subset of these streams using synoptic sampling of multiple constituents under baseflow and highflow conditions. Study results indicate that water chemistry is spatially dynamic and can be influenced by both groundwater dilution and inputs from tributaries. Lastly, I investigated patterns in selenium bioaccumulation across and within streams, from particulate matter to top trophic levels (i.e. fish and salamanders). I found that benthic macroinvertebrates had the highest concentrations of selenium in these ecosystems, with lower concentrations in salamander and fish species. However, there was limited evidence of longitudinal trends in bioaccumulation dynamics downstream of mining impacts. Collectively, this work indicates long-term (ca. decades) coal-mining influences but also highlights future research needs to better understand downstream impacts to water quality and biotic communities.