A5015860443- Aquatic Ecosystems and Phytoplankton Dynamics
- Marine and coastal ecosystems
- Soil and Water Nutrient Dynamics
- Microbial Community Ecology and Physiology
- Aquatic Invertebrate Ecology and Behavior
- Fish Ecology and Management Studies
- Aquatic Ecosystems and Biodiversity
- Isotope Analysis in Ecology
- Freshwater macroinvertebrate diversity and ecology
- Biocrusts and Microbial Ecology
- Water Quality and Pollution Assessment
- Environmental DNA in Biodiversity Studies
- Marine Toxins and Detection Methods
- Constructed Wetlands for Wastewater Treatment
- Diatoms and Algae Research
- Ecology and biodiversity studies
- Groundwater and Isotope Geochemistry
- Bacteriophages and microbial interactions
- Heavy metals in environment
- Genomics and Phylogenetic Studies
- Peatlands and Wetlands Ecology
- Oceanographic and Atmospheric Processes
- Protist diversity and phylogeny
- Algal biology and biofuel production
- Atmospheric and Environmental Gas Dynamics
Ohio Sea Grant College Program
2016-2025
The Ohio State University
2016-2025
Bowling Green State University
2023
University of Toledo
2009-2014
Science Applications International Corporation (United States)
2006
In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends agricultural practices are consistent increasing phosphorus loading to western basin of lake, and these trends, coupled meteorological conditions spring produced record-breaking nutrient loads. An extended period weak lake circulation then led abnormally long residence incubated bloom,...
Phosphorus (P) is generally considered to be the main limiting nutrient freshwater phytoplankton productivity. However, recent research drawing attention importance of nitrogen (N) in eutrophication and N often constrains growth cyanobacteria small lakes. In this study we determined limitation a large lake, Lake Erie during two growing seasons. During 2010 2011, enrichment bioassays (+P, +N and, +P N) were conducted monthly from June through September with water collected Maumee Bay (site...
Cyanobacterial Harmful Algal Blooms (CyanoHABs) commonly increase water column pH to alkaline levels ≥9.2, and as high 11. This elevated has been suggested confer a competitive advantage cyanobacteria such Microcystis aeruginosa . Yet, there is limited information regarding the restrictive effects bloom-induced may impose on this cyanobacterium’s competitors. Due pH-dependency of biosilicification processes, diatoms (which seasonally both precede proceed blooms in many fresh waters) be...
Cyanobacterial harmful algal blooms (cyanoHABs) degrade freshwater ecosystems globally. Microcystis aeruginosa often dominates cyanoHABs and produces microcystin (MC), a class of hepatotoxins that poses threats to human animal health. Microcystin toxicity is influenced by distinct structural elements across diversity related molecules encoded variant
Cyanobacteria harmful algal blooms produce many toxic secondary metabolites called cyanotoxins. The most studied group of cyanotoxins are microcystins (MC), with over 300 congeners reported. MC-LR is the congener because its abundance and toxicity. Recent toxicology studies suggest that more hydrophobic MC such as MC-LA, MC-LF, MC-LW may be less abundant but up to seven times than MC-LR, whereas, MC-RR's toxicity only one-fifth MC-LR. Hence, understanding environmental stressors change...
Abstract Hypoxia, defined as dissolved oxygen (DO) < 2 mg/L, in the central basin of Lake Erie has been studied since mid‐1900s. Even so, spatial patterns hypoxia, and episodic hypoxia nearshore areas where drinking water plant intakes are located, not well characterized owing to limited observations short‐term dynamics. We evaluated a physically based, DO model with respect observed Erie. The used assigned rates sediment column demand that were temperature dependent but otherwise...
Abstract The rediscovery of diatom blooms embedded within and beneath the Lake Erie ice cover (2007–2012) ignited interest in psychrophilic adaptations winter limnology. Subsequent studies determined vital role plays ecophysiology as diatoms partition to underside ice, thereby fixing their location photic zone. Yet, climate change has led widespread decline across Great Lakes, with presenting a nearly “ice-free” state several recent winters. It been hypothesized that resultant turbid,...
Cyanobacterial harmful algal bloom (CyanoHAB) proliferation is a global problem impacting ecosystem and human health. Western Lake Erie (WLE) typically endures two highly toxic CyanoHABs during summer: Microcystis spp. in Maumee Bay that extends throughout the western basin, Planktothrix Sandusky Bay. Recently, USA Canada agreed to 40% phosphorus (P) load reduction lessen severity of WLE blooms. To investigate nitrogen (N) limitation biomass toxin production CyanoHABs, we conducted situ...
Abstract. Recent global water quality crises point to an urgent need for greater understanding of cyanobacterial harmful algal blooms (cHABs) and their drivers. Nearshore areas Lake Erie such as Sandusky Bay may become seasonally limited by nitrogen (N) are characterized distinct cHAB compositions (i.e., Planktothrix over Microcystis). This study investigated phytoplankton N uptake pathways, determined drivers depletion, the budget in Bay. Nitrate (NO3-) ammonium (NH4+) uptake, fixation,...
We discuss the uncertainty associated with a commonly used method for measuring concentration of microcystin, group toxins cyanobacterial blooms. Such is rarely reported and accounted in important drinking water management decisions. Using monitoring data from Ohio Environmental Protection Agency City Toledo, we document sources measurement recommend Bayesian hierarchical modeling approach reducing uncertainty. Our analysis suggests that (1) much result highly uncertain "standard curve"...
Abstract Cyanobacterial biomass forecasts currently cannot predict the concentrations of microcystin, one most ubiquitous cyanotoxins that threaten human and wildlife health globally. Mechanistic insights into how microcystin production biodegradation by heterotrophic bacteria change spatially throughout bloom season can aid in toxin concentration forecasts. We quantified during two growth seasons western Lake Erie sites with different physicochemical properties commonly plagued summer...
Cyanobacterial blooms in the western basin of Lake Erie have been well studied with a focus on planktonic Microcystis and cyanotoxin microcystin, but recent research has shown that are not entirely Microcystis. Previous studies documented other taxa capable producing cyanotoxins. Furthermore, benthic cyanobacteria historically overlooked Erie. Saxitoxin is emerging concern freshwater, sxtA gene which encodes its production found Maumee River central Collectively, these points indicated...
Abstract Toxic harmful algal blooms produce public health hazards in freshwater systems around the world. There is a need for forecast that can mitigate risk of exposure to toxins. We improved an approach predict spatially and temporally resolved probability microcystins (MCs) exceeding threshold level (6 μg L −1 ) western Lake Erie. This combines 5‐day chlorophyll‐a model, weekly updated regression model predicting MCs from chlorophyll‐a, empirical relationship between predicted observed...