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Harmful Algal Bloom Research Initiative Year 3 Report


The third-year report continues to show that the state of Ohio has benefited from the initiative.

Technical Bulletin

Harmful Algal Bloom Research Initiative Year 3 Report Executive Summary


Harmful Algal Bloom Research Initiative Year 3 Report Executive Summary

Technical Bulletin

Twine Line Spring/Summer 2018

Twine Line Spring/Summer 2018

Making Lake Erie Science Come Alive

Ohio Sea Grant celebrates its 40th anniversary with a special issue of Twine Line, packed with science, research and education stories from the past, present and future of the program.

VOLUME: 40 ISSUE: 2 LENGTH: 35 pages
Twine Line

Stone Lab Guest Lecture: Ohio EPA


Research Brief
Development of a Lake Erie cyanobacterial bloom toxicity forecast
Dr. Justin Chaffin, Senior Researcher & Research Coordinator, Stone Laboratory

Guest Lecture
Emerging Drinking Water Contaminants
Craig Butler, Director, Ohio Environmental Protection Agency (OEPA)

DURATION: ~ 1 hr, 44 mins
Broadcast, Podcast, Webinar

Stone Lab Guest Lecture: 2018 Lake Erie Harmful Algal Bloom Forecast


Stone Lab Guest Lecture: a 2018 update on the research and state of harmful algal blooms in Lake Erie.

DURATION: ~ 1 hr, 48 mins
Broadcast, Podcast, Webinar

2018 Lake Erie HABs Forecast


Dr. W. Russell Callender
Assistant Administrator, NOAA’s National Ocean Service
Partnering to Address the Impacts of Harmful Algal Blooms (HABs) to Lake Erie’s Communities and Economies

Dr. Laura Johnson
Director, National Center for Water Quality Research, Heidelberg University
Maumee River Loadings: March – July 2018

Dr. Rick Stumpf
Oceanographer, NOAA’s National Centers for Coastal Ocean Science
2018 Forecast of the Western Lake Erie Harmful Algal Bloom

Dr. Christopher Winslow
Director, Ohio Sea Grant & Stone Laboratory
An Overview of the Harmful Algal Bloom Research Initiative (HABRI) in Ohio

DURATION: ~ 2 hrs, 1 min
Broadcast, Podcast, Webinar

Charter Boat Captains Help Monitor Lake Erie Water Quality


Monitoring the health of Lake Erie is no small task, and it can’t be done alone. That’s why Stone Lab works with private charter captains on the lake to help collect water samples and monitor the algae and toxin levels in the water.

LENGTH: 1 page
Technical Summary

What Are Harmful Algal Blooms?


Ohio Sea Grant is discussing harmful algal blooms and their impact on Lake Erie as part of an ongoing video series. In this video, we cover what harmful algal blooms are, what makes them harmful, when they typically occur, their impact throughout the lake and what you should know to be aware of a bloom.

This project was partially funded by a Great Lakes HABs Collaboratory grant.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

What Are Harmful Algal Blooms?

Harmful algal blooms were all over the news after the Toledo drinking water crises of 2011 and 2014, but what actually causes these algal blooms and why are they problematic? This online fact sheet will provide you with answers about what makes up a harmful algal bloom, why they form, why they're an issue, and what you can do to help prevent them and keep yourself safe.
Fact Sheet

Early onset of a microcystin-producing cyanobacterial bloom in and agriculturally-influenced Great Lakes tributary


In late May 2016, a cyanobacterial harmful algal bloom (cHAB) was detected in the Maumee River, the largest tributary to Lake Erie, the southernmost lake of the Laurentian Great Lakes system. Testing on 31 May identified Planktothrix agardhii as the dominant cyanobacterium with cell abundance exceeding 1.7×10 9 cells/L and total microcystins (MC) reaching 19 μg/L MC-LR equivalents, a level over 10-fold higher than the 2015 revised U.S. Environmental Protection Agency (EPA) national health advisory levels for drinking water exposure to adults. Low river discharge coincident with negligible precipitation through the latter half of May coincided with an 80% decline in river turbidity that likely favored bloom formation by a low-light adapted P. agardhii population. Also contributing to the cHAB were high initial nutrient loads and an increase of the river temperature from 13°C to 26°C over this same period. The bloom persisted through 5 June with microcystins exceeding 22 μg/L MC-LR equivalents at the bloom peak. By 6 June, the river had returned to its muddy character following a rain event and sampling on 7 June detected only low levels of toxin (<0.6 μg/L) at public water systems located near the bloom origin. The elevated toxin production associated with this early onset bloom was without precedent for the Maumee River and an unique attribute of the cHAB was the high proportion of potentially-toxic genotypes. Whereas Planktothrix spp. is common in lotic environments, and has been previously detected in the Maumee, blooms are not commonly reported. This early onset, microcystin-producing cHAB provided a rare opportunity to glean insights into environmental factors that promote bloom development and dominance by Planktothrix in lotic environments.

LENGTH: 13 pages
External Partner Publication

Nitrogen cycling in Sandusky Bay, Lake Erie: oscillations between strong and weak export and implications for harmful algal blooms


Recent global water quality crises point to an urgent need for greater understanding of cyanobacterial harmful algal blooms (cHABs) and their drivers. Nearshore areas of Lake Erie such as Sandusky Bay may become seasonally limited by nitrogen (N) and are characterized by distinct cHAB compositions (i.e., Planktothrix over Microcystis). This study investigated phytoplankton N uptake pathways, determined drivers of N depletion, and characterized the N budget in Sandusky Bay. Nitrate (NO3−) and ammonium (NH4+) uptake, N fixation, and N removal processes were quantified by stable isotopic approaches. Dissimilatory N reduction was a relatively modest N sink, with denitrification, anammox, and N2O production accounting for 84, 14, and 2% of sediment N removal, respectively. Phytoplankton assimilation was the dominant N uptake mechanism, and NO3− uptake rates were higher than NH4+ uptake rates. Riverine N loading was sometimes insufficient to meet assimilatory and dissimilatory demands, but N fixation alleviated this deficit. N fixation made up 23.7–85.4% of total phytoplankton N acquisition and indirectly supports Planktothrix blooms. However, N fixation rates were surprisingly uncorrelated with NO3− or NH4+ concentrations. Owing to temporal separation in sources and sinks of N to Lake Erie, Sandusky Bay oscillates between a conduit and a filter of downstream N loading to Lake Erie, delivering extensively recycled forms of N during periods of low export. Drowned river mouths such as Sandusky Bay are mediators of downstream N loading, but climate-change-induced increases in precipitation and N loading will likely intensify N export from these systems.

VOLUME: 15 LENGTH: 16 pages
External Partner Publication

Optimization of extraction methods for quantification of microcystin-LR and microcystin-RR in fish, vegetable, and soil matrices using UPLC–MS/MS


Human-driven environmental change has increased the occurrence of harmful cyanobacteria blooms in
aquatic ecosystems. Concomitantly, exposure to microcystin (MC), a cyanobacterial toxin that can
accumulate in animals, edible plants, and agricultural soils, has become a growing public health concern.
For accurate estimation of health risks and timely monitoring, availability of reliable detection methods is
imperative. Nonetheless, quantitative analysis of MCs in many types of biological and environmental
samples has proven challenging because matrix interferences can hinder sample preparation and extraction procedures, leading to poor MC recovery. Herein, controlled experiments were conducted to
enhance the use of ultra-performance liquid-chromatography tandem-mass spectrometry (UPLC–MS/
MS) to recover MC-LR and MC-RR at a range of concentrations in seafood (fish), vegetables (lettuce), and environmental (soil) matrices. Although these experiments offer insight into detailed technical aspects of the MC homogenization and extraction process (i.e., sonication duration and centrifugation speed during homogenization; elution solvent to use during the final extraction), they centered on identifying the best (1) solvent system to use during homogenization (2–3 tested per matrix) and (2) single-phase extraction (SPE) column type (3 tested) to use for the final extraction. The best procedure consisted of the following, regardless of sample type: centrifugation speed = 4200 xg; elution volume = 8 mL; elution solvent = 80% methanol; and SPE column type = hydrophilic–lipophilic balance (HLB), with carbon also being satisfactory for fish. For sonication, 2 min, 5 min, and 10 min were optimal for fish, lettuce, and soil matrices, respectively. Using the recommended HLB column, the solvent systems that led to the highest recovery of MCs were methanol:water:butanol for fish, methanol:water for lettuce, and EDTA-Na4P2O7
for soils. Given that the recommended procedures resulted in average MC-LR and MC-RR recoveries that
ranged 93 to 98%, their adoption for the preparation of samples with complex matrices before UPLC–MS/
MS analysis is encouraged.

VOLUME: 76 LENGTH: 10 pages
External Partner Publication

Twine Line Winter/Spring 2018

Twine Line Winter/Spring 2018

Twine Line Winter/Spring 2018. Twine Line gets ready for summer. Learn how travel benefits our state and the ways that research at Stone Lab is improving the quality of our drinking water, plus lots more in this issue of Twine Line.

VOLUME: 40 ISSUE: 1 LENGTH: 19 pages
Twine Line

Summary of Findings and Strategies to Move Toward a 40% Phosphorus Reduction


White Paper: Summary of Findings and Strategies to Move Toward a 40% Phosphorus Reduction

LENGTH: 13 pages
External Partner Publication

Attached Algae: The Cryptic Base of Inverted Trophic Pyramids in Freshwaters


It seems improbable that a thin veneer of attached algae coating submerged surfaces in lakes and rivers could be the foundation of many freshwater food webs, but increasing evidence from chemical tracers supports this view. Attached algae grow on any submerged surface that receives enough light for photosynthesis, but animals often graze attached algae down to thin, barely perceptible biofilms. Algae in general are more nutritious and digestible than terrestrial plants or detritus, and attached algae are particularly harvestable, being concentrated on surfaces. Diatoms, a major component of attached algal assemblages, are especially nutritious and tolerant of heavy grazing. Algivores can track attached algal productivity over a range of spatial scales and consume a high proportion of new attached algal growth in high-light, low-nutrient ecosystems. The subsequent efficient conversion of the algae into consumer production in freshwater food webs can lead to low-producer, high-consumer biomass, patterns that Elton (1927) described as inverted trophic pyramids. Human perturbations of nutrient, sediment, and carbon loading into freshwaters and of thermal and hydrologic regimes can weaken consumer control of algae and promote nuisance attached algal blooms.

External Partner Publication

Intercomparison of Approaches to to the Empirical Line Method for Vicarious Hyperspectral Reflectance Calibration


Analysis of visible remote sensing data research requires removing atmospheric effects by conversion from radiance to at-surface reflectance. This conversion can be achieved through theoretical radiative transfer models, which yield good results when well-constrained by field observations, although these measurements are often lacking. Additionally, radiative transfer models often perform poorly in marine or lacustrine settings or when complex air masses with variable aerosols are present. The empirical line method (ELM) measures reference targets of known reflectance in the scene. ELM methods require minimal environmental observations and are conceptually simple. However, calibration coefficients are unique to the image containing the reflectance reference. Here we compare the conversion of hyperspectral radiance observations obtained with the NASA Glenn Research Center Hyperspectral Imager to at-surface reflectance factor using two reflectance reference targets. The first target employs spherical convex mirrors, deployed on the water surface to reflect ambient direct solar and hemispherical sky irradiance to the sensor. We calculate the mirror gain using near concurrent at-sensor reflectance, integrated mirror radiance, and in situ water reflectance. The second target is the Lambertian-like blacktop surface at Maumee Bay State Park, Oregon, OH, where reflectance was measured concurrently by a downward looking, spectroradiometer on the ground, the aerial hyperspectral imager and an upward looking spectroradiometer on the aircraft. These methods allows us to produce an independently calibrated at-surface water reflectance spectrum, when atmospheric conditions are consistent. We compare the mirror and blacktop-corrected spectra to the in situ water reflectance, and find good agreement between methods. The blacktop method can be applied to all scenes, while the mirror calibration method, based on direct observation of the light illuminating the scene validates the results. The two methods are complementary and a powerful evaluation of the quality of atmospheric correction over extended areas. We decompose the resulting spectra using varimax-rotated, principal component analysis, yielding information about the underlying color producing agents that contribute to the observed reflectance factor scene, identifying several spectrally and spatially distinct mixtures of algae, cyanobacteria, illite, haematite, and goethite. These results have implications for future hyperspectral remote sensing missions, such as PACE, HyspIRI, and GeoCAPE.

LENGTH: 20 pages

Ohio Sea Grant eNewsletter August 2017


Ever wonder what the inside of and island lab looks like? Come take a look at this year’s Stone Lab Open house!


2017 Lake Erie Harmful Algal Bloom Forecast Summary


Stone Lab gives it’s 2017 forecast for Harmful Algal Blooms in lake Erie, and provides information on HABs.

Broadcast, Podcast, Webinar

Stone Lab Guest Lecture: Shale Development in Ohio


Jiyoung Lee, The Ohio State University

Shale Development in Ohio and a Case Study of Horizontal Drilling – Rover Pipeline
Craig Butler, Ohio EPA

DURATION: ~ 1 hr, 54 mins
Broadcast, Podcast, Webinar

2017 HABs Using Bateria to Degrade Microcystin (Huntley)


Jason Huntley explores how we might be able to use bacteria to help deal with harmful algal blooms in Lake Erie.

External Partner Publication

2017 HABs Lake Erie HABs Forecast System (Kavanaugh)


Slideshow explaining NOAA’s Harmful Algal Bloom Forecast System.

External Partner Publication

Forecast for Harmful Algal Blooms in Lake Erie in 2017


Ohio Sea Grant and Stone Laboratory hosted a public webinar to explain NOAA’s 2017 Seasonal Forecast of Harmful Algal Blooms for Lake Erie. The event featured expert commentary, a discussion of the history of this issue on Lake Erie, and the U.S. response to the problem.

DURATION: ~ 2 hrs, 1 min
Broadcast, Podcast, Webinar

Stone Lab Guest Lecture: Monitoring Cyanobacterial Blooms


Harmful algal bloom (HAB) experts from NOAA’s 2017 Harmful Algal Bloom Forecast shared some of the forecast information and background on algal blooms.

DURATION: ~ 1 hr, 40 mins
Broadcast, Podcast, Webinar

Harmful Algal Bloom Research Initiative Year 2 Report Executive Summary


Harmful Algal Bloom Research Initiative Year 2 Report Executive Summary

LENGTH: 14 pages
Technical Bulletin

Community Biological Ammonium Demand: A Conceptual Model for Cyanobacteria Blooms in Eutrophic Lakes


Cyanobacterial harmful algal blooms (Cyano-HABs) are enhanced by anthropogenic pressures, including excessive nutrient (nitrogen, N, and phosphorus, P) inputs and a warming climate. Severe eutrophication in aquatic systems is often manifested as non-N2-fixing CyanoHABs (e.g., Microcystis spp.), but the biogeochemical relationship between N inputs/dynamics and CyanoHABs needs definition. Community biological ammonium (NH4+) demand (CBAD) relates N dynamics to total microbial productivity and NH4+ deprivation in aquatic systems. A mechanistic conceptual model was constructed by combining nutrient cycling and CBAD observations from a spectrum of lakes to assess N cycling interactions with CyanoHABs. Model predictions were supported with CBAD data from a Microcystis bloom in Maumee Bay, Lake Erie, during summer 2015. Nitrogen compounds are transformed to reduced, more bioavailable forms (e.g., NH4+ and urea) favored by CyanoHABs. During blooms, algal biomass increases faster than internal NH4+ regeneration rates, causing high CBAD values. High turnover rates from cell death and remineralization of labile organic matter consume oxygen and enhance denitrification. These processes drive eutrophic systems to NH4+ limitation or colimitation under warm, shallow conditions and support the need for dual nutrient (N and P) control.

VOLUME: 51 LENGTH: 8 pages
External Partner Publication

Old Habits are Hard to Break: Modern HABs, Nitrogen, Lake Management


Researchers Dr. Mark J. McCarthy, Justin A. Myers, and Dr. Silvia E. Newell discuss the roles that nitrogen and phosphorous play in creating harmful algal blooms, methods for tracking Nitrogen, and ways to reduce their loading into water sources, thus reducing harmful algal blooms (HABs).

LENGTH: 3 pages
External Partner Publication

The Cuyahoga River Area of Concern


The Cuyahoga River isn’t at risk of catching fire anymore, but that doesn’t mean it’s in great shape either. The Cuyahoga River is a designated Area of Concern. This fact sheet explains what that means, and what’s being done to fix it.

LENGTH: 1 page
Fact Sheet

Multiple Models Guide Strategies for Agricultural Nutrient Reductions


In response to degraded water quality, federal policy makers in the US and Canada called for a 40% reduction in phosphorus (P) loads to Lake Erie, and state and provincial policy makers in the Great Lakes region set a load-reduction target for the year 2025. Here, we configured five separate SWAT (US Department of Agriculture’s Soil and Water Assessment Tool) models to assess load reduction strategies for the agriculturally dominated Maumee River watershed, the largest P source contributing to toxic algal blooms in Lake Erie. Although several potential pathways may achieve the target loads, our results show that any successful pathway will require large-scale implementation of multiple practices. For example, one successful pathway involved targeting 50% of row cropland that has the highest P loss in the watershed with a combination of three practices: subsurface application of P fertilizers, planting cereal rye as a winter cover crop, and installing buffer strips. Achieving these levels of implementation will require local, state/provincial, and federal agencies to collaborate with the private sector to set shared implementation goals and to demand innovation
and honest assessments of water quality-related
programs, policies, and partnerships.

DOI: 10.1002/fee.1472 VOLUME: 15 ISSUE: 3 LENGTH: 6 pages

Microcystis Rising: Why Phosphorus Reduction Isn’t Enough to Stop CyanoHABs


Toxic Microcystis blooms have become a regular summertime event on Lake Erie; this 2011 bloom was particularly bad. Microcystis is well adapted to the high nutrient loads that affect Erie and other lakes and estuaries. Researchers are studying the role of nitrogen in controlling the growth and toxin production of this hardy cyanobacterium.

DOI: 10.1289 VOLUME: 125 ISSUE: 2 LENGTH: 5 pages

Fertilizer Placement and Application Timing as Strategies to Reduce Phosphorus Loading to Lake Erie


To reduce the intensity and frequency of harmful algal blooms in western Lake Erie, it has been recommended to reduce the phosphorus load, contributed by the Maumee River watershed (MRW) in northwest Ohio. As the largest contributor of phosphorus to Lake Erie, the dominantly agricultural MRW in northwest Ohio has been recommended to reduce phosphorus loads by 40%. To achieve such reductions, three agricultural nutrient management practices, (1) fertilizer placement within the soil, (2) adjusted seasonal timing of fertilizer application, and (3) adjusted date of fertilizer application to drier days have been recommended. To determine the potential phosphorus load reduction from implementing these three management practices, a SWAT model of the MRW was developed to evaluate the effectiveness of each practice for reducing SRP and total phosphorus (TP) load to the lake. Management scenarios were modeled with variations of the three practices from 2007 to 2012, and compared to historical data. Overall, maximum fertilizer placement had the greatest potential to influence SRP and TP loads; reducing spring SRP and TP loading by 42% and 27%, respectively compared to baseline levels. Seasonal fertilizer application timing also impacted spring SRP and TP loads, but to a lesser degree. Changing the date of application from wetter days to drier days across the watershed did not significantly affect SRP or TP loads, but this result is likely due to limitations of the SWAT simulation. These results indicate that maximizing fertilizer placement has a great potential to reduce TP and SRP runoff from the MRW.

DOI: 10.1016/j.jglr.2016.07.002 VOLUME: 42 ISSUE: 6 LENGTH: 7 pages

It Takes Two to Tango: When and Where Dual Nutrient (N & P) Reductions Are Needed to Protect Lakes and Downstream Ecosystems


Preventing harmful algal blooms (HABs) is needed to protect lakes and downstream ecosystems. Traditionally, reducing phosphorus (P) inputs was the prescribed solution for lakes, based on the assumption that P universally limits HAB formation. Reduction of P inputs has decreased HABs in many lakes, but was not successful in others. Thus, the “P-only” paradigm is overgeneralized. Whole-lake experiments indicate that HABs are often stimulated more by combined P and nitrogen (N) enrichment rather than N or P alone, indicating that the dynamics of both nutrients are important for HAB control. The changing paradigm from P-only to consideration of dual nutrient control is supported by studies indicating that (1) biological N fixation cannot always meet lake ecosystem N needs, and (2) that anthropogenic N and P loading has increased dramatically in recent decades. Sediment P accumulation supports long-term internal loading, while N may escape via denitrification, leading to perpetual N deficits. Hence, controlling both N and P inputs will help control HABs in some lakes and also reduce N export to downstream N-sensitive ecosystems. Managers should consider whether balanced control of N and P will most effectively reduce HABs along the freshwater-marine continuum.

DOI: 10.1021/acs.est.6b02575 VOLUME: 50 ISSUE: 20 LENGTH: 8 pages

Forecast for Harmful Algal Blooms in Lake Erie in 2016


Forecast of Harmful Algal Blooms in Lake Erie for 2016. Consists of commentary from numerous involved scientists and features eight speakers.

LENGTH: 141 pages
Broadcast, Podcast, Webinar

HABs FAQs: Are Fish Caught in a Harmful Algal Bloom Safe to Eat?


Dr. Stuart Ludsin answers the question “Are fish caught in or near a harmful algal bloom safe to eat?”

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: How is drinking water treated to remove microcystin?


Ohio Sea Grant Special Advisor Dr. Jeffery Reutter answers the question “How is drinking water treated to remove microcystin?”

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: What level of exposure to microcystin in drinking water is dangerous?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffry Reutter answers the question “What level of exposure to microcystin in drinking water is dangerous?”

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: Is the air near an algae bloom dangerous to inhale?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffrey Reutter answers the question “Is the air near an algae bloom dangerous to inhale?”

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: How can I help lower the amount of phosphorus runoff?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffrey Reutter gives advice for helping reduce the amount of phosphorous that runs into Lake Erie.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: What is the difference between microcystis and microcystin?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffrey Reutter explains the difference between microcysis and microcystin.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: How quickly will Lake Erie recover if we reduce phosphorus runoff?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffry Reutter answers the question “How quickly will Lake Erie recover if we reduce phosphorus runoff?”

LENGTH: 1 page
Broadcast, Podcast, Webinar

HABs FAQs: What Conditions Cause a Harmful Algal Bloom?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffrey Reutter explains what conditions facilitate a harmful algal bloom.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

HABs FAQs: What Steps Can We Take to Reduce or Eliminate Harmful Algal Blooms?


Frequently Asked Questions Harmful Algal Blooms — Ohio Sea Grant Special Advisor Dr. Jeffrey Reutter explains the main steps we need to take to prevent harmful algal blooms.

DURATION: ~ 1 min
Broadcast, Podcast, Webinar

Characterization of The Persistent Cyanobacterial Bloom, Planktothrix in Sandusky Bay, Lake Erie


Planktothrix sp. is less studied than other bloom-forming cyanobacteria. The aim of this study was to determine characteristics of the Planktothrix bloom in Sandusky Bay. Using the 2013 Sandusky Bay metagenome and 2014 summer samples, it was found that the bloom in Sandusky Bay has limited diversity and is continuously dominated by Planktothrix. Nutrient profiles of the Bay suggest nitrogen limitation throughout the bloom season. Physical parameters recorded in Sandusky Bay are suboptimal for many known bloom-forming cyanobacteria. Given this information, it is not yet understood how Planktothrix survives and dominates Sandusky Bay. Future work will look further at community members playing a role in the nitrogen cycle in the Bay. Additionally, the succession of genotypes will be determined over time as the environmental parameters will be monitored over a longer period of time to determine how survival of Planktothrix is supported.

Thesis / Dissertation

Stone Lab Guest Lecture: Great Lakes Water Quality Agreement


Stone Lab Guest Lecture
Tinka Hyde, Water Division Director, US Environmental Protection Agency Region 5
Great Lakes Water Quality Agreement: Annex 4 Recommendations to Address HAB, Hypoxia, and Cladophora Problems on Lake Erie

Research Brief
Justin Chaffin, Ohio Sea Grant & Stone Lab
The Role of Nitrogen in Regulating Cyanobacterial Bloom Toxicity

DURATION: ~ 2 hrs, 5 mins
Broadcast, Podcast, Webinar

National Oceanic and Atmospheric Administration Harmful Algal Blooms Forecast 2015 Webinar


On July 9, 2015, Ohio Sea Grant’s Stone Laboratory hosted a public webinar to explain NOAA’s 2015 Seasonal Forecast of Harmful Algal Blooms for Lake Erie. The event featured expert commentary, a discussion of the history of this issue on Lake Erie, and Ohio’s response to the problem.

DURATION: ~ 1 hr, 52 mins
Broadcast, Podcast, Webinar

Harmful Algal Blooms Primer 2015


Harmful Algal Blooms (HABs) in Lake Erie and other Ohio lakes impact water quality, public health and recreation. This 3-part overview introduces the basics of the problem, as well as some solutions currently in the works at Ohio State and its partner institutions.

DURATION: 53 mins
Broadcast, Podcast, Webinar

Harmful Algal Blooms Kiosk Panel


Ever wonder why Lake Erie looks…like that?

It’s the algae! This tabletop dispay has info all about the harmful algal blooms that plague Lake Erie.

LENGTH: 1 page

Effects of Increasing Nitrogen and Phosphorus Concentrations on Phytoplankton Community Growth and Toxicity During Planktothrix Blooms in Sandusky Bay, Lake Erie


Sandusky Bay experiences annual toxic cyanobacterial blooms dominated by Planktothrix agardhii/suspensa. To further understand the environmental drivers of these events, we evaluated changes in the growth response and toxicity of the Planktothrix-dominated blooms to nutrient amendments with orthophosphate (PO4) and inorganic and organic forms of dissolved nitrogen (N; ammonium (NH4), nitrate (NO3) and urea) over the bloom season (June – October). We complemented these with a metagenomic analysis of the planktonic microbial community. Our results showed that bloom growth and microcystin (MC) concentrations responded more frequently to additions of dissolved N than PO4, and that the dual addition of NH4 + PO4 and Urea + PO4 yielded the highest MC concentrations in 54% of experiments. Metagenomic analysis confirmed that P. agardhii/suspensa was the primary MC producer. The phylogenetic distribution of nifH revealed that both heterocystous cyanobacteria and heterotrophic proteobacteria had the genetic potential for N2 fixation in Sandusky Bay. These results suggest that as best management practices are developed for P reductions in Sandusky Bay, managers must be aware of the negative implications of not managing N loading into this system as N may significantly impact cyanobacterial bloom size and toxicity.

DOI: 10.1021/acs.est.5b00799 VOLUME: 49 ISSUE: 12 LENGTH: 10 pages

An Automated Approach to Agricultural Tile Drain Detection and Extraction Utilizing High Resolution Aerial Imagery and Object-based Image Analysis


Subsurface drainage from agricultural fields in the Maumee River watershed is suspected
to adversely impact the water quality and contribute to the formation of harmful algal
blooms (HABs) in Lake Erie. In early August of 2014, a HAB developed in the western
Lake Erie Basin that resulted in over 400,000 people being unable to drink their tap water
due to the presence of a toxin from the bloom. HAB development in Lake Erie is aided
by excess nutrients from agricultural fields, which are transported through subsurface tile
and enter the watershed. Compounding the issue within the Maumee watershed, the trend
within the watershed has been to increase the installation of tile drains in both total extent
and density. Due to the immense area of drained fields, there is a need to establish an
accurate and effective technique to monitor subsurface farmland tile installations and
their associated impacts.
This thesis aimed at developing an automated method in order to identify subsurface tile
locations from high resolution aerial imagery by applying an object-based image analysis
(OBIA) approach utilizing eCognition. This process was accomplished through a set of
algorithms and image filters, which segment and classify image objects by their spectral
and geometric characteristics. The algorithms utilized were based on the relative location
of image objects and pixels, in order to maximize the robustness and transferability of the
final rule-set. These algorithms were coupled with convolution and histogram image
filters to generate results for a 10km² study area located within Clay Township in Ottawa
County, Ohio.
The eCognition results were compared to previously collected tile locations from an
associated project that applied heads-up digitizing of aerial photography to map field tile.
The heads-up digitized locations were used as a baseline for the accuracy assessment.
The accuracy assessment generated a range of agreement values from 67.20% – 71.20%,
and an average agreement of 69.76%. The confusion matrices calculated a range of
kappa values from 0.273 – 0.416 with an overall K value of 0.382, considered fair in
strength of agreement. This thesis provides a step forward in the ability to automatically
identify and extract tile drains, and will assist future research in subsurface agricultural
drainage modeling.

LENGTH: 77 pages
Thesis / Dissertation

National Oceanic and Atmospheric Administration Harmful Algal Blooms Forecast 2014 Webinar


Recording of NOAA’s 2014 harmful algal blooms forecast, issued from Stone Lab.


NOAA and its research partners predict that western Lake Erie will have a significant bloom of cyanobacteria, a toxic blue-green algae, during the 2014 bloom season in late summer. However, the predicted bloom is expected to be smaller than last year’s intense bloom, and considerably less than the record-setting 2011 bloom. Bloom impacts will vary across the lake’s western basin and are classified by an estimate of both its concentration and how far it spreads.

DURATION: ~ 1 hr, 3 mins
Broadcast, Podcast, Webinar

Climate Change and Harmful Algal Blooms in Maumee Bay Webinar


This webinar covers the potential for future algal blooms in Lake Erie’s western basin.


Harmful algal blooms (HABs) are a global problem and have reemerged as a concern in Lake Erie during the last decade. While some have hypothesized HABs in Lake Erie will become more frequent and larger, there are few studies linking predicted climate and watershed models to examine this issue. This talk will describe the methods and results of an ongoing project that links climate models, watershed models and HABs models to predict the frequency and magnitude of HABs through 2099.
This webinar will describe:

Predicted climate for the Maumee Basin through 2099
How climate change is likely to affect river discharge and harmful algal blooms in western Lake Erie
Modeling tools that can help people understand and manage the impacts of extreme weather events and climate change

DURATION: ~ 1 hr, 4 mins
Broadcast, Podcast, Webinar
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