Nonlinear Relationship of Near-Bed Velocity and Growth of Riverbed Periphyton
AbstractArtificial streams were set up to test the relationship between near-bed water velocity and periphyton growth. Periphyton community samples collected from a Japanese stream were incubated for 44 days under a light intensity of 252 ± 72 μmol·photons/m2·s, a temperature of 20–25 °C, and three near-bed water velocity classes: low (<17.9 cm/s), moderate (17.9–32.8 cm/s), and high (>32.8 cm/s). A logistic model was applied to estimate the maximum net growth rate (μmax) and carrying capacity (Bmax). A response surface method was also applied to estimate chlorophyll a (Chl-a) and ash-free dry mass (AFDM) with respect to the independent variables (i.e., time and water velocity). We detected both the highest μmax (1.99 d−1) and highest Bmax (7.01 mg/m2) for Chl-a at the moderate water velocity. For AFDM, we observed the highest μmax (0.57 d−1) and Bmax (1.47 g/m2) at the low and moderate velocity classes, respectively. The total algae density in the region of moderate velocity at the end of the experiment was 6.47 × 103 cells/cm2, corresponding to levels 1.7 and 1.3 times higher than those at lower and higher velocities, respectively. Our findings indicated that the moderate near-bed water velocity provided favorable conditions for algal growth and corresponding biomass accumulation. View Full-Text
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Ateia, M.; Nasr, M.; Ikeda, A.; Okada, H.; Fujii, M.; Natsuike, M.; Yoshimura, C. Nonlinear Relationship of Near-Bed Velocity and Growth of Riverbed Periphyton. Water 2016, 8, 461.
Ateia M, Nasr M, Ikeda A, Okada H, Fujii M, Natsuike M, Yoshimura C. Nonlinear Relationship of Near-Bed Velocity and Growth of Riverbed Periphyton. Water. 2016; 8(10):461.Chicago/Turabian Style
Ateia, Mohamed; Nasr, Mahmoud; Ikeda, Akira; Okada, Hisako; Fujii, Manabu; Natsuike, Masafumi; Yoshimura, Chihiro. 2016. "Nonlinear Relationship of Near-Bed Velocity and Growth of Riverbed Periphyton." Water 8, no. 10: 461.