Source: OSU Media
Attached algae, aquatic plants, and invertebrate animals driver water quality and fish disease dynamics in the Klamath River, but relatively little is known about how dam removal will affect these parts of the river ecosystem. The ecology team is researching relationships between water quality, fish disease risk, and the aquatic plants and animals (worms!) that influence them. We are investigating patterns and drivers of aquatic plants, algae, and worm proliferation before and after the dam removal to better understand how these components of the river ecosystem will respond to dam removal, with the goal of identifying specific mechanisms that contribute to poor water quality and fish disease risk . These components directly link to concepts of river health that are being examined with the Socio-Cultural interviews and through the Decision Modeling components of this project.
Algae and Rooted Aquatic Plants
Algae and aquatic plants provide the basis for aquatic food webs, influence water quality, and control carbon cycling in rivers. Despite the importance of algae and plants to freshwater ecosystems, increased growth and accumulation of algae, cyanobacteria, and aquatic plants beyond historic levels is a growing problem in rivers. Excess growth of algae and aquatic plants in the Klamath River impedes tribal fishing practices, prohibits river access, and causes extreme fluctuations in dissolved oxygen and pH. The conditions that promote high algae growth also promote toxin-producing taxa that lead to public health concerns, further exacerbating people’s ability to safely access the river.
We are documenting growth and accumulation of algal and aquatic plants before and after dam removal and investigating their seasonal growth to understand how dam removal will affect algae and aquatic plants. By linking habitat characteristics to areas of high plant and algae growth, we will increase understanding of what physical and chemical changes associated with dam removal will affect production. Linking biomass of aquatic plants to long-term records of daily primary production will facilitate understanding how algae and aquatic plant growth influences rates of production that control managed water quality parameters, including pH and dissolved oxygen in the river.
Source: OSU Media
Salmon parasites
The myxozoan parasite Ceratonova shasta (C.shasta) causes mortality (up to 90% in some years) in outmigrating juvenile salmon. The parasite alternately infects annelid (worm) and salmon hosts in order to complete its life cycle. The annelid hosts release the (short-lived) parasite stage that infects the salmon so understanding the factors that drive the distribution and density of infected annelids is central to managing of disease risk in juvenile and adult salmon. This study informs our knowledge of annelid host ecology by describing diets of the suspension feeding annelids, and how reservoir removal and subsequent changes in the algae and aquatic plants in the river in turn affect annelid host density or distribution.
Dissolved Oxygen
Dissolved oxygen is necessary for the survival of fish and other wildlife in rivers. In the Klamath River, the amount of dissolved oxygen can be affected my several environmental factors, such as temperature, primary production, turbulence, and sediment pulses.
During sediment pulses, large quantities of sand, silt, clay, and organic matter (like dead plants or algae) can get pushed through the river by landslides, fires, heavy rain, or the removal of dams. These sediment pulses can block sunlight from reaching the riverbed, inhibiting photosynthesis and affecting the amount of oxygen being produced in the river. Additionally, sediment pulses contain organic matter, such as plant and algae particles. These particles attract microorganisms, such as bacteria, that decompose the organic matter. These microorganisms breathe in oxygen just like us, and can consume significant quantities of oxygen from the river.
When the dam is removed, the sediment currently trapped behind the dam will be flushed into the river, and will remain the river for up to one year. This part of the study aims to quantify the amount of dissolved oxygen consumed by the sediment pulse and model the recovery of dissolved oxygen as the sediment pulse makes its way out of the Klamath River.
Meet the Ecology Team
Desiree Tullos, PhD, PE (OR)
Professor, Water Resources Engineering
Oregon State University
Julie Alexander, PhD
Assistant Professor (Senior Research)
Oregon State University, Department of Microbiology
Laurel Genzoli
PhD candidate
University of Montana
Kristine Alford
PhD StudentOregon
State University
