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Crustacean and rotifer density and biomass were measured from 2014 to 2025 in five drinking water reservoirs in southwestern Virginia, USA. These reservoirs are: Beaverdam Reservoir (Vinton, Virginia), Falling Creek Reservoir (Vinton, Virginia), Carvins Cove Reservoir (Roanoke, Virginia), Gatewood Reservoir (Pulaski, Virginia), and Spring Hollow Reservoir (Salem, Virginia). Beaverdam, Falling Creek, Carvins Cove, and Spring Hollow Reservoirs are owned and operated by the Western Virginia Water Authority as primary or secondary drinking water sources for Roanoke, Virginia, and Gatewood Reservoir is a drinking water source for the Town of Pulaski, Virginia. The dataset consists of integrated vertical tow samples from the whole water column, just the epilimnion, and just the hypolimnion (as the difference between the full water column and epilimnion tows), as well as discrete depth measurements collected with a Schindler trap. Most samples were collected at the deepest site of each reservoir adjacent to the dam. Sampling frequency and duration varied among reservoirs and years and included weekly to monthly routine monitoring as well as intensive 24-hour sampling campaigns. In 2014-2016, zooplankton samples were collected approximately fortnightly in the spring, summer, and autumn months at Beaverdam Reservoir, Carvins Cove Reservoir, and Gatewood Reservoirs. Falling Creek Reservoir samples were collected weekly to monthly in spring and summer 2014, and Spring Hollow Reservoir samples were collected approximately fortnightly in the spring, summer, and autumn months of 2015 and 2016. In 2019, zooplankton samples were collected approximately weekly to monthly from April to November at Beaverdam Reservoir and April to September at Falling Creek Reservoir. In 2020, zooplankton samples were collected approximately weekly to monthly from May to December at Beaverdam Reservoir and June to September at Falling Creek Reservoir. In 2021, zooplankton were collected monthly from March to December in Beaverdam Reservoir. In 2022, zooplankton were collected monthly from January to May at Beaverdam Reservoir. In 2023-2025, zooplankton were collected approximately monthly from March or April to December in Beaverdam Reservoir. Falling Creek Reservoir zooplankton samples were sparsely collected during 2021 to 2025. During the 24-hour sampling campaigns conducted in Beaverdam Reservoir from 2019-2022, samples were collected from both the deepest pelagic site and a shallow littoral site.
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Zooplankton community variability in the South Atlantic Bight (2015–2017)
Abstract In the South Atlantic Bight (SAB), responses of zooplankton communities to physical dynamics were evaluated monthly at two sites on the continental shelf offshore from Savannah, GA, USA, between December 2015 and December 2017. Zooplankton were collected in oblique net tows (202-μm). Samples were collected in two regions of the middle shelf: inner edge (Site 1: 25 m isobath, n = 22) and outer edge (Site 2: 40 m isobath, n = 21). Samples were also collected at a third site on the 40 m isobath, ~20 nm south of Site 2 in July and August 2016. Temperature, salinity and fluorescence data were recorded at each site. Overall, 57 taxa were identified with total abundances varying from 1 × 103 to 81 × 103 ind.m−3. Small copepods predominated; notably Paracalanus spp. The highest abundance was recorded in October 2016 at Site 1, following deep mixing induced by Hurricane Matthew. Interannual variability of zooplankton abundance was significant, with higher abundances in 2016 compared with 2017, reflecting higher river runoff in 2016. Samples from Site 3 yielded the largest Dolioletta gegenbauri bloom documented in the SAB. This 2-year time-series, for the first time, suggests that zooplankton communities on the SAB middle shelf region are significantly influenced by continental precipitation patterns.
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- PAR ID:
- 10395216
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Plankton Research
- Volume:
- 45
- Issue:
- 2
- ISSN:
- 0142-7873
- Format(s):
- Medium: X Size: p. 312-324
- Size(s):
- p. 312-324
- Sponsoring Org:
- National Science Foundation
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