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The structural complexity of oyster reef canopy plays a major role in promoting biodiversity, balancing the sediment budget, and modulating hydrodynamics in estuarine systems. Although oyster canopy structure is both spatially and temporally heterogeneous, oyster canopies are generally characterized using simple first‐order quantities, like oyster density, which may lack the ability to sufficiently parameterize reef roughness. In this study, a novel laser‐scan approach was used to map the surface of intact reference and restored reefs (restoration age: 1–4 years) during low tide, when the oyster canopy was fully exposed. Measurements were used to estimate hydrodynamically relevant roughness characteristics over the entire reef surface (>140 m2; 0.50 m resolution), providing estimates of the canopy height (hc), standard deviation (), rugosity index (R), and fractal dimension (D). Average canopy heights ranged from 3.6 to 4.9 cm, with canopy height standard deviations between 1.4 and 2.0 cm. Mean rugosity indices and fractal dimensions were relatively low on the youngest (1 year) restored reef (R = 1.28;D = 2.67), with substantial increases observed for more mature reef canopies (4 years:R = 1.56;D = 2.71). Structural complexity was consistently greater on reef margins than in reef interiors. Increases in complexity were linked to restoration age, with older reefs exhibiting more complex oyster canopies. The highest fractal dimension was observed on the intact reference reef, highlighting the importance of sustained reef growth for maintaining higher‐order structural complexity. Results provide spatially explicit surface roughness characterizations for healthy, intertidal oyster reefs, with applications in both restoration science and natural and nature‐based feature design.
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Mean flow and turbulence observations on reference and restored oyster reefs in Mosquito Lagoon - Florida from 2018-06-01 to 2018-11-15 (NCEI Accession 0225430)
Hydrodynamic experiments were conducted on reference and restored oyster reefs in Mosquito Lagoon, Florida (USA) between June and November 2018. Measurements were collected on intact, degraded, and restored (restoration age: 6month, 2years, 4years) oyster reefs (Crassostrea virginica) to investigate differences in flow and turbulence characteristics related to restoration age. The dataset presented herein includes hydrodynamic observations (timeseries) from experiments conducted on five different oyster reefs (Reference, R-2017, R-2016, R-2014, Degraded), with measurements that include: (1) forcing characteristics (wave heights, water depths, wind speeds, channel velocities), (2) reef characteristics (oyster densities, solid volume fractions), and (3) near-bed flow and turbulence observations (flow speeds, turbulent energy, turbulent kinetic energy dissipation, shear production) from within and above the oyster canopy on sample reefs. Data are presented as timeseries (column vectors) in nine .txt files, with one file for each experiment.
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- PAR ID:
- 10327364
- Publisher / Repository:
- NOAA National Centers for Environmental Information
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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