Relationship between Sediment Transport and Primary Production

Estimating productivity in headwater streams is challenging. This study presents a method using dissolved oxygen saturation (DOsat) and photosynthetically active radiation (PAR) to create DOsat–PAR curves, similar to photosynthesis–irradiance curves, for estimating gross primary productivity (GPP). Data from two Oregon streams were used—one for model development and the other for validation. The slope of the DOsat–PAR relationship varied widely but showed strong correlations with GPP (r² > 0.78). The model captured productivity responses to a storm event and aligned well with estimates from a Bayesian model. This approach offers a simple, effective tool for assessing headwater stream productivity (Pub 47).

In a study we investigated how channel bed disturbance influences benthic chlorophyll a (Chl-a) accrual in rivers in Colorado and Oregon. Using hydraulic modeling and sediment analysis, researchers found that disturbance occurs even at low flows. In Colorado, Chl-a increased with time but was limited by local disturbance, low temperatures, and nutrient availability. In Oregon, shear stress explained nearly half of Chl-a variability, with biomass patterns driven by disturbance magnitude and recovery stage. Low-shear zones resisted scour but recovered slowly, while high-shear zones recovered quickly. Findings emphasize the complex interplay between hydrodynamic forces and algal dynamics across spatial and temporal scales (Pub 33)

Early efforts explored how channel bed disturbance affects benthic chlorophyll a (Chl-a) in rivers in Colorado and Oregon. Hydraulic modeling and sediment data showed that disturbance occurs even at low flows. In Colorado, periphyton biomass increased exponentially but was limited by disturbance, cold temperatures, and low nutrients. In Oregon, mean shear stress explained 49% of Chl-a variation, with biomass depending on both disturbance intensity and recovery stage. Low-shear areas resisted disturbance but recovered slowly, while high-shear zones showed rapid loss and faster recovery. Results highlight the complex relationship between geomorphic processes and algal dynamics across space and time (Pubs 4, 17).

Publications

47. *Villamizar S., Segura, C., &  Warren, D. Using stream dissolved oxygen and light relationships to estimate stream primary production on mountainous headwater streams ecosystems. Ecohydrology, e2699. https://doi.org/10.1002/eco.2699

33. *Cargill, S., Segura, C., *Villamizar, S., and Warren., D. 2021. The influence of lithology on stream metabolism in headwater systems, Ecohydrology;e2284. https://doi.org/10.1002/eco.2284

32. Heaston, E.D., Segura, C. and Warren, D.R. 2020, Do electrofishing activities impact stream biofilm standing stocks? An assessment from two headwater streams in western Oregon. North American Journal of Fisheries Management. Accepted Author Manuscript. https://doi.org/10.1002/nafm.10549

17. *Katz S, Segura C, Warren DR.  2018.  The influence of channel bed disturbance on benthic Chlorophyll a: A high resolution perspective. Geomorphology 305 141-153.

4.  Segura C, McCutchan JH, Lewis Jr WM, Pitlick J.  2011.  The influence of channel bed disturbance on algal biomass in a Colorado mountain stream. Ecohydrology. 4, 411-421.