2007
Warnaars, T.; Hondzo, M.; Power, M. E.
Abiotic controls on periphyton accrual and metabolism in streams: Scaling by dimensionless numbers Journal Article
In: Water Resources Research, vol. 43, no. 8, 2007.
Abstract | Links | BibTeX | Tags: Metabolism, periphyton, scaling
@article{Warnaars2007,
title = {Abiotic controls on periphyton accrual and metabolism in streams: Scaling by dimensionless numbers},
author = {T. Warnaars and M. Hondzo and M. E. Power},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Warnaars_2007_WaterResRes.pdf},
doi = {10.1029/2006WR005002},
year = {2007},
date = {2007-08-23},
journal = {Water Resources Research},
volume = {43},
number = {8},
abstract = {[1] Increasingly available high-resolution topographic data from remote sensing motivates the search for topographic features that predict abiotic controls on the distribution and performance of biota. We investigated the extent to which periphyton distribution and stream ecosystem metabolism in a steep upland river drainage network could be predicted from physical conditions that varied with local topography. During the summers of 2003 and 2004, we measured periphyton standing crops and gross primary production and ecosystem respiration rates along a 5 km reach of the South Fork Eel River and six of its tributaries in northern California (39°44′N, 123°39′W). We also measured wetted stream width (B), cross-sectionally averaged stream velocity (U), and streambed photosynthetically active solar radiation (PAR) at each site to investigate the degree to which periphyton abundance and metabolism were related to these indicators, which in turn are partially predictable from models relating environmental parameters to the topographic settings. Dimensional analysis, a technique widely used in the field of fluid mechanics, was used to investigate how biotic and abiotic variables may be interconnected in stream environments. Nondimensional groups of variables were formulated on the basis of our field estimates of chosen biotic and abiotic variables. Periphyton biomass was controlled by B9/5, exposure to light PAR1/5, nutrient concentration N5/6, and inverse stream depth H−5/6 and U−1/2. The autotrophic-heterotrophic balance, quantified by the gross primary production to ecosystem respiration rate, scaled with the stream aspect ratio (B/H)equation image and Peclet number Pe = (UB/u*H)equation image, where u* is the shear stress velocity. The scaling relationships were validated against reported field measurements from other geographical areas. The results show nonlinear dependencies among periphyton biomass, stream metabolism, and abiotic variables. These nonlinear relationships point to a need for detailed quantification of biotic and abiotic variables over a range of scales.},
keywords = {Metabolism, periphyton, scaling},
pubstate = {published},
tppubtype = {article}
}
[1] Increasingly available high-resolution topographic data from remote sensing motivates the search for topographic features that predict abiotic controls on the distribution and performance of biota. We investigated the extent to which periphyton distribution and stream ecosystem metabolism in a steep upland river drainage network could be predicted from physical conditions that varied with local topography. During the summers of 2003 and 2004, we measured periphyton standing crops and gross primary production and ecosystem respiration rates along a 5 km reach of the South Fork Eel River and six of its tributaries in northern California (39°44′N, 123°39′W). We also measured wetted stream width (B), cross-sectionally averaged stream velocity (U), and streambed photosynthetically active solar radiation (PAR) at each site to investigate the degree to which periphyton abundance and metabolism were related to these indicators, which in turn are partially predictable from models relating environmental parameters to the topographic settings. Dimensional analysis, a technique widely used in the field of fluid mechanics, was used to investigate how biotic and abiotic variables may be interconnected in stream environments. Nondimensional groups of variables were formulated on the basis of our field estimates of chosen biotic and abiotic variables. Periphyton biomass was controlled by B9/5, exposure to light PAR1/5, nutrient concentration N5/6, and inverse stream depth H−5/6 and U−1/2. The autotrophic-heterotrophic balance, quantified by the gross primary production to ecosystem respiration rate, scaled with the stream aspect ratio (B/H)equation image and Peclet number Pe = (UB/u*H)equation image, where u* is the shear stress velocity. The scaling relationships were validated against reported field measurements from other geographical areas. The results show nonlinear dependencies among periphyton biomass, stream metabolism, and abiotic variables. These nonlinear relationships point to a need for detailed quantification of biotic and abiotic variables over a range of scales.
2003
Finlay, Jacques C.
Controls of streamwater dissolved inorganic carbon dynamics in a forested watershed Journal Article
In: Biogeochemistry, vol. 62, no. 3, pp. 231-252, 2003, ISSN: 1573-515X.
Abstract | Links | BibTeX | Tags: CO2, Dissolved inorganic carbon, Metabolism, Stable carbon isotopes, streams, Weathering
@article{Finlay2003,
title = {Controls of streamwater dissolved inorganic carbon dynamics in a forested watershed},
author = {Jacques C. Finlay},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/Controls-of-streamwater-dissolved-inorganic-carbon-dynamics-in-a-forested-watershed_Finlay_2002.pdf},
doi = {10.1023/A:1021183023963},
issn = {1573-515X},
year = {2003},
date = {2003-03-01},
journal = {Biogeochemistry},
volume = {62},
number = {3},
pages = {231-252},
abstract = {I investigated controls of stream dissolved inorganic carbon (DIC) sources andcycling along a stream size and productivity gradient in a temperate forestedwatershed in northern California. Dissolved CO2 (CO2(aq))dynamics in heavily shaded streams contrasted strongly with those of larger,open canopied sites. In streams with canopy cover > 97%, CO2 (aq)was highest during baseflow periods (up to 540 μM) and wasnegatively related to discharge. Effects of algal photosynthesis on CO2(aq) were minimal and stream CO2 (aq) was primarily controlledby groundwater CO2 (aq) inputs and degassing losses to theatmosphere. In contrast to the small streams, CO2 (aq) in larger,open-canopied streams was often below atmospheric levels at midday duringbaseflow and was positively related to discharge. Here, stream CO2(aq) was strongly influenced by the balance between autotrophic andheterotrophic processes. Dynamics of HCO3 − werelesscomplex. HCO3 − and Ca2+ were positivelycorrelated, negatively related to discharge, and showed no pattern with streamsize. Stable carbon isotope ratios of DIC (i.e. δ13C DIC)increased with stream size and discharge, indicating contrasting sources of DICto streams and rivers. During summer baseflows, δ13C DIC were13C-depleted in the smallest streams (minimum of−17.7‰) due to the influence of CO2 (aq) derived frommicrobialrespiration and HCO3 − derived from carbonateweathering. δ13C DIC were higher (up to −6.6‰)inthe larger streams and rivers due to invasion of atmospheric CO2enhanced by algal CO2 (aq) uptake. While small streams wereinfluenced by groundwater inputs, patterns in CO2 (aq) and evidencefrom stable isotopes demonstrate the strong influence of stream metabolism andCO2 exchange with the atmosphere on stream and river carbon cycles.},
keywords = {CO2, Dissolved inorganic carbon, Metabolism, Stable carbon isotopes, streams, Weathering},
pubstate = {published},
tppubtype = {article}
}
I investigated controls of stream dissolved inorganic carbon (DIC) sources andcycling along a stream size and productivity gradient in a temperate forestedwatershed in northern California. Dissolved CO2 (CO2(aq))dynamics in heavily shaded streams contrasted strongly with those of larger,open canopied sites. In streams with canopy cover > 97%, CO2 (aq)was highest during baseflow periods (up to 540 μM) and wasnegatively related to discharge. Effects of algal photosynthesis on CO2(aq) were minimal and stream CO2 (aq) was primarily controlledby groundwater CO2 (aq) inputs and degassing losses to theatmosphere. In contrast to the small streams, CO2 (aq) in larger,open-canopied streams was often below atmospheric levels at midday duringbaseflow and was positively related to discharge. Here, stream CO2(aq) was strongly influenced by the balance between autotrophic andheterotrophic processes. Dynamics of HCO3 − werelesscomplex. HCO3 − and Ca2+ were positivelycorrelated, negatively related to discharge, and showed no pattern with streamsize. Stable carbon isotope ratios of DIC (i.e. δ13C DIC)increased with stream size and discharge, indicating contrasting sources of DICto streams and rivers. During summer baseflows, δ13C DIC were13C-depleted in the smallest streams (minimum of−17.7‰) due to the influence of CO2 (aq) derived frommicrobialrespiration and HCO3 − derived from carbonateweathering. δ13C DIC were higher (up to −6.6‰)inthe larger streams and rivers due to invasion of atmospheric CO2enhanced by algal CO2 (aq) uptake. While small streams wereinfluenced by groundwater inputs, patterns in CO2 (aq) and evidencefrom stable isotopes demonstrate the strong influence of stream metabolism andCO2 exchange with the atmosphere on stream and river carbon cycles.