Great Lakes Area Research Articles

Assessment of shoreline restoration using macroinvertebrates in a Great Lakes Area of Concern.

Macroinvertebrate community assemblages were examined in three areas of the littoral zone of an impacted, drowned river mouth lake in west Michigan, USA. Muskegon Lake has an extensive history of environmental abuse, resulting in its listing as a Great Lakes Area of Concern. A multi-organizational, shoreline restoration initiative was started in 2009 and completed in 2012. Despite pre- and post-restoration monitoring of water quality, fish assemblages, and macrophytes, no studies had examined the shifts in the littoral zone macroinvertebrate community. Using Hester-Dendy samplers, we collected macroinvertebrates monthly in submergent, emergent, and open macrophyte zones, at two restored sites and one reference site from August 2018 to October 2019. No pre-restoration samples were collected at these sites but we could examine the changes in restored vs. reference sites. In total, 22,931 individuals were observed, with Gammarus spp., Echinogammarus spp., Chironominae, and Dreissena polymorpha being among the most abundant taxa. NMDS results revealed overlap among macroinvertebrate communities between the two restored sites and separation from the reference site, with some overlapping seasonal differences and communities influenced by macrophyte habitat type. Principal components analysis revealed that the environmental factors were strongly influenced by seasonal changes and drove habitat-level differences, rather than spatial variations among sites. Our results indicate that although the macroinvertebrate community composition at the restored sites differed from that at the reference site, the macroinvertebrate assemblage at each site was dominated by tolerant generalist species. Pollution-sensitive macroinvertebrate taxa may have been reduced or eliminated in the lake due to decades of environmental abuse. Periodic monitoring is recommended to determine if these sensitive taxa return, as Muskegon Lake conditions continue to improve.

Assessing exposures to per- and polyfluoroalkyl substances in two populations of Great Lakes Basin fish consumers in Western New York State.

Fish and other seafood are an important dietary source of per- and polyfluoroalkyl substances (PFAS) exposure in many areas of the world, and PFAS were found to be pervasive in fish from the Great Lakes area. Few studies, however, have examined the associations between Great Lakes Basin fish consumption and PFAS exposure. Many licensed anglers and Burmese refugees and immigrants residing in western New York State consume fish caught from the Great Lakes and surrounding waters, raising their risk of exposure to environmental contaminants including PFAS. The aims of this study were to: 1) present the PFAS exposure profile of the licensed anglers and Burmese refugees and 2) examine the associations between serum PFAS levels and local fish consumption. Licensed anglers (n=397) and Burmese participants (n=199) provided blood samples and completed a detailed questionnaire in 2013. We measured 12 PFAS in serum. Multiple linear regression was used to assess associations between serum PFAS concentrations and self-reported consumption of fish from Great Lakes waters. Licensed anglers and Burmese participants reported consuming a median of 16 (IQR: 6-36) and 88 (IQR: 44-132) meals of locally caught fish in the year before sample collection, respectively (data for Burmese group restricted to 10 months of the year). Five PFAS were detected in almost all study participants (PFOS, PFOA, PFHxS, PFNA and PFDA; 97.5-100%). PFOS had the highest median serum concentration in licensed anglers (11.6ng/mL) and the Burmese (35.6ng/mL), approximately two and six times that of the U.S. general population, respectively. Serum levels of other PFAS in both groups were generally low and comparable to those in the general U.S. Among licensed anglers, Great Lakes Basin fish meals over the past year were positively associated with serum PFOS (P<0.0001), PFDA (P<0.0001), PFHxS (P=0.01), and PFNA (P=0.02) and the number of years consuming locally caught fish was positively associated with serum PFOS (P=0.01) and PFDA (P=0.01) levels. In the Burmese group, consuming Great Lakes Basin fish more than three times a week in the past summer was positively associated with serum PFOS (P=0.004) and PFDA (P=0.02) among the Burmese of non-Karen ethnicity, but not among those of Karen ethnicity, suggesting potential ethnic differences in PFAS exposure. Great Lakes Basin fish consumption was associated with an increase in blood concentrations of some PFAS, and especially of PFOS, among licensed anglers and Burmese refugees and immigrants in western New York State. In the Burmese population, there may be other important PFAS exposure routes related to residential history and ethnicity. Continued outreach efforts to increase fish advisory awareness and reduce exposure to contaminants are needed among these populations.

Symbolic Use of Language as a Means to Demonstrate Accommodation

This paper reports on how a prominent American football player, Joe Burrow, from the state of Ohio adopts the Cajun English spelling system used in Louisiana, a southern state in the U.S., in a symbolic and innovative way during his short stay there when he relocated to Louisiana from Ohio for the final two years of his college career. In previous studies of language attitudes toward English dialects in the U.S., Michiganders evaluated the English used in the Great Lakes area (including Ohio) as the best variety while judging the English spoken in the South (including Louisiana) as the worst. Although Burrow may not carry such language attitude, it is implicitly demonstrated in media coverage related to his college football career. Despite the harsh folk evaluation and rather negative portrait from the media of the Southern U.S. English, Burrow’s accommodation to the Cajun English spelling was a means to express his gratitude to the state of Louisiana and resonated through the U.S. in various ways.

Analysis of incentive policies for phosphorus recovery at livestock facilities in the Great Lakes area

Livestock operations have been highly intensified over the last decades, resulting in the advent of large concentrated animal feeding operations (CAFOs). Intensification decreases production costs but also leads to substantial environmental impacts. Specifically, nutrient runoff from livestock waste results in eutrophication, harmful algal blooms, and hypoxia. The implementation of nutrient recovery systems in CAFOs can abate nutrient releases and negative ecosystem responses, although they might negatively affect the economic performance of CAFOs. We design and analyze potential incentive policies for the deployment of phosphorus recovery technologies at CAFOs considering the geospatial vulnerability to nutrient pollution. The case study demonstration consists of 2217 CAFOs in the U.S. Great Lakes area. The results reveal that phosphorus recovery is more economically viable in the largest CAFOs due to economies of scale, although they also represent the largest eutrophication threats. For small and medium-scale CAFOs, phosphorus credits progressively improve the profitability of nutrient management systems. The integration of biogas production does not improve the economic performance of phosphorus recovery systems at most of CAFOs, as they lack enough size to be cost-effective. Phosphorus recovery proves to be economically beneficial by comparing the net costs of nutrient management systems with the negative economic impact derived from phosphorus releases. The incentives necessary for avoiding up to 20.7.103 ton/year phosphorus releases and achieve economic neutrality in the Great Lakes area are estimated at $223 million/year. Additionally, the fair distribution of limited incentives is studied using a Nash allocation scheme, determining the break-even point for allocating monetary resources.

Environmental Justice and Great Lakes Areas of Concern: Addressing the Need for More Research

Environmental Justice and Great Lakes Areas of Concern: Addressing the Need for More Research

Uncertainty Characterization in PM2.5 Estimates Across the Contiguous US

BACKGROUND AND AIM: Accurate PM2.5 exposure assessment, often performed using statistical prediction models, is a critical component of health studies and regulatory action. Ensemble modeling is becoming increasingly popular as it improves accuracy by combining the unique strengths of different models. Identifying where prediction uncertainty is greatest can inform monitor deployment and model development. We fit an ensemble model integrating multiple existing PM2.5 prediction models, estimated location-specific uncertainty in predictions, and then identified factors contributing to uncertainty. METHODS: We predicted 2015 annual PM.5 concentrations at 0.01°×0.01° resolution across the contiguous US by combining three well-validated prediction models with the Bayesian Non-parametric Ensemble (BNE). Training data came from the US Environmental Protection Agency's Air Quality System database. We estimated model uncertainty, which captures disagreement between models, uncertainty of weights, and random error, as the standard deviations of predictions’ location-specific posterior predictive distribution. We analyzed how predicted PM2.5, AQS monitor count within a 50-km radius, summer- and winter-mean temperature, and population density vary with uncertainty via a generalized additive mixed model, with penalized splines and a random intercept for state. RESULTS:Mean (standard deviation; SD) predicted PM2.5 was 6.37 μg/m3 (1.78), with a spatial RMSE of 0.71 μg/m^3, and mean (SD) uncertainty was 0.47 (0.20) μg/m^3. We observed greater uncertainty in the Midwest and Great Lakes areas. Predicted concentration had a complex relationship with uncertainty, with a generally positive association above ~8 μg/m^3. Monitor density had a negative association. Winter temperature below 0°C was positively associated with uncertainty, and summer temperature was positively associated below 19°C and negatively above 19°C. Very high population density was associated with lower uncertainty. CONCLUSIONS:PM2.5 prediction uncertainty varied across space; uncertainty was greater in areas with more pollution, fewer monitors, colder winters, more moderate summers, and lower population density. Subsequent monitoring and prediction model development should consider prioritizing these areas. KEYWORDS: Exposure assessment, particulate matter, spatial statistics

A geospatial environmental and techno-economic framework for sustainable phosphorus management at livestock facilities

Nutrient pollution of waterbodies is a major worldwide water quality problem. Excessive use and discharge of nutrients can lead to eutrophication and algal blooms in fresh and marine waters, resulting in environmental problems associated with hypoxia, public health issues related to the release of toxins and freshwater scarcity. A promising option to address this problem is the recovery of nutrient releases prior to being discharged into the environment. Driven by the sustainable materials management concept, the COW2NUTRIENT (Cattle Organic Waste to NUTRIent and ENergy Technologies) framework is developed for the techno-economic evaluation and selection of nutrient recovery systems at livestock facilities. Environmental vulnerability to nutrient pollution determined through a geographic information system (GIS)-based model and techno-economic information of different state-of-the-art nutrient management technologies are combined in a multi-criteria decision analysis (MCDA) model, resulting in the selection and economic analysis of the most suitable process for each studied livestock facility. This framework has been employed for studying the implementation of sustainable phosphorus management systems at 2,217 livestock facilities in the Great Lakes area, resulting in capital expenses of 2.5 billion USD if only phosphorus recovery technologies are installed, and up to 5.2 billion USD if nutrient management is combined with biogas and power production. However, considering potential economic incentives for the recovery of phosphorus, net revenues up to 230 million USD per year can be achieved. Therefore, the framework presented reveals the potential of implementing nutrient management systems at regional scale for the abatement of phosphorus releases from livestock facilities.

Sea lamprey control in the Great Lakes: A Tribal/First Nations Representative’s perspective

Sea lamprey control has been a dominant feature in the Great Lakes since the Great Lakes Fishery Commission (GLFC) formation in 1955. Review and recommendations on the sea lamprey control program are undertaken by a Sea Lamprey International Symposium (SLIS) held every twenty years beginning in 1979. In the forty-year history of the SLIS, this is the first paper on Indigenous perspectives in the published outputs and is an important inaugural step for the SLIS. However, one singular paper does not represent the viewpoints of the many independent Indigenous communities of the Great Lakes area. Willingness to understand the Indigenous perspective is the first step toward trust responsibility obligations and consultation with Tribes in the U.S. and engagement with First Nations in Canada. Indigenous peoples’ belief systems can include kinship ties between human and nature. In turn, this dictates respectful relationships toward all life forms. As such sea lamprey (Petromyzon marinus) can be considered a life form to merit respect which can be incongruent with contemporary sea lamprey control strategies. Perhaps it is time to consider future reviews of sea lamprey control within an Indigenous context and knowledge framework to assist in an equitable and sustainable future for the Great Lakes.

Biomonitoring of toxic metals, organochlorine pesticides, and polybrominated biphenyl 153 in Michigan urban anglers

The 32-mile Detroit River and surrounding tributaries have been designated as a Great Lakes Area of Concern due to pollution from decades of municipal and industrial discharges, sewer overflows and urban development. The Agency for Toxic Substances and Disease Registry and the Michigan Department of Health and Human Services conducted a biomonitoring study to assess exposures to persistent toxic substances in Detroit urban shoreline anglers who may be at high exposure risk due to consumption of locally caught fish. Using a modified venue-based sampling approach, 287 adult shoreline anglers along the Detroit River were recruited and participated in the program. Study participants provided blood and urine specimens and completed a questionnaire interview. In this report, we examine percentile estimates for blood lead, blood manganese, urine arsenic, urine mercury, urine cadmium, organochlorine pesticides in serum (mirex, hexachlorobenzene, chlordane), and serum polybrominated biphenyl 153 (PBB 153) concentrations among study participants. Multiple linear regression was used to identify predictors of contaminant concentrations. The Detroit urban anglers' blood lead concentrations were 2 times higher than the general adult U.S. population (median (95% CI): 2.9 μg/dL (1.8–2.3) vs. 0.94 μg/dL (0.90–0.98)). PBB 153 levels were 1.8 times higher than the general adult U.S. population at the 95th percentile (95th percentile, 95% CI: 62.7 ng/g of lipid, 53.2–75.2 vs. 34.6 ng/g of lipid, 12.8–66.8). Percentile estimates of the other study pollutants were similar to background levels found in the general U.S. population. Eating more locally caught fish was not associated with increased body burdens for any of the contaminants examined in this report. Higher blood lead was associated with increased age, male sex, current smoking, residing in a home built before 1960, an annual income less than $25,000, and a work history of lead paint removal. Evidence of PBB exposure in our study cohort likely reflects the continued effect of a widespread contamination of livestock feed in 1973 among Michigan's lower peninsula population. These study results help determine if the pollutants examined warrant further consideration in subsequent population-based biomonitoring of frequent consumers of fish from the Detroit River and surrounding waterways. The biomonitoring data from this study also served to inform public health officials regarding the potential need for environmental public health actions to reduce harmful exposures.

Cold and wet: Diatoms dominate the phytoplankton community during a year of anomalous weather in a Great Lakes estuary

As sentinels of climate change and other anthropogenic forces, freshwater lakes are experiencing ecosystem disruptions at every level of the food web, beginning with the phytoplankton, a highly responsive group of organisms. Most studies regarding the effects of climate change on phytoplankton focus on a potential scenario in which temperatures continuously increase and droughts intersperse heavy precipitation events. Like much of the conterminous United States in 2019, the Muskegon River watershed (Michigan, USA) experienced record-breaking rainfall accompanied by unusually cool temperatures, affording an opportunity to explore how an alternate potential climate scenario may affect phytoplankton. We conducted biweekly sampling of environmental variables and phytoplankton in Muskegon Lake, a Great Lakes Area of Concern that connects to Lake Michigan. We compared environmental variables in 2019 to the previous eight years using long-term data from the Muskegon Lake Observatory buoy, and annual monitoring excursions provided historical phytoplankton data. Under cold and wet conditions, diatoms were the single dominant division throughout the entire growth season – an unprecedented scenario in Muskegon Lake. In 10 of the 13 biweekly sampling days in 2019, diatoms comprised over 75% of the phytoplankton community in the lake by count, indicating that the spring diatom bloom persisted through the fall. Additionally, phytoplankton seasonal succession and abundance patterns typically seen in this lake were absent. In a world experiencing reduced predictability, increased variability, and regional climate anomalies, studying periods of extreme weather events may offer insight into how natural systems will be affected and respond under future climate scenarios.

Characterisation and geodynamic setting of the 1 Ga granitoids of the Karagwe-Ankole belt (KAB), Rwanda

The Karagwe-Ankole belt (KAB) is a poorly understood deformation belt in the Great Lakes area of Central Africa, with several hypotheses put forward to explain the emplacement of the various generations of granites. The youngest generation of granites (G4; 1000 Ma) are spatially associated with Sn-W-Ta ore deposits, and are considered as the parental granites. The paragenesis of these mineral resources have been extensively scrutinised, but the geodynamic context and characterisation of these parental granites has been neglected. Tectonic models for the formation of this plutonic suite range from an intra-cratonic to full-scale continent–continent collision setting.In this study, the G4 intrusive suite of the KAB granites, are characterised based on whole-rock geochemical analysis and U-Pb zircon dating.Two main populations of U-Pb zircon ages are identified in the G4 granites at 1370–1420 Ma and 950–1020 Ma. The older population is attributed to inheritance of the bimodal magmatic Kibaran event, while the younger population is ascribed to the new crystallisation. G4 granites contain xenocrystic zircon, indicating inheritance of older granites or basement rocks. G4 granites are, however, much more differentiated compared to older Kibaran granites, containing higher K and Rb and lower Ca, Sr and Ba concentrations, which implicates recycling of older crustal material. The variable geochemistry, as well as the different proportions of xenocrystic zircons in the different granite bodies, suggest melting was highly localised and derived from a highly heterogeneous source region, for which an intracontinental setting is favoured. The Th/U ratios of the parental granites are lower than 0.1, which would suggest a metamorphic origin of the granites. Together with the low luminescence signal of these zircons an anatectic origin of the melt is considered, implying that the parental granites could be considered more like migmatites rather than actual granites formed by fractionation out of large magma chambers.

Evolving Institutional Arrangements for use of an ecosystem approach in restoring Great Lakes Areas of Concern.

The 1987 Canada-U.S. Great Lakes Water Quality Agreement required Remedial Action Plans (RAPs) be collaboratively generated between local stakeholders and government agencies to implement an ecosystem approach in cleaning up 43 historically polluted Areas of Concern (AOCs) throughout the Laurentian Great Lakes. The institutional arrangements that have emerged over the past 35 years to foster an ecosystem approach in RAPs are expected to have changed over time and be varied in some aspects—reflecting unique socio-ecological contexts of each AOC—while also sharing some characteristics that were either derived from the minimally prescribed framework or developed convergently. Here we surveyed institutional arrangements to describe changes over time relevant to advancing an ecosystem approach in restoring beneficial uses in the 43 AOCs. While eight AOCs evidenced little institutional change, the remaining 35 AOCs demonstrated a growing involvement of local organizations in RAPs, which has enhanced local capacity and ownership and helped strengthen connections to broader watershed initiatives. We also noted an expansion of strategic partnerships that has strengthened science-policy-management linkages and an increasing emphasis on sustainability among RAP institutions. Our study details how institutional arrangements in a decentralized restoration program have evolved to implement an ecosystem approach and address new challenges

The Shattered Cross: French Catholic Missionaries on the Mississippi River, 1698-1725 by Linda Carol Jones

Reviewed by: The Shattered Cross: French Catholic Missionaries on the Mississippi River, 1698-1725 by Linda Carol Jones Kenneth C. Carstens Linda Carol Jones. The Shattered Cross: French Catholic Missionaries on the Mississippi River, 1698-1725. Baton Rouge: LSU Press, 2020. Pp. 297. Figures. Index. Maps. Notes. Cloth: $50.00. I have been fascinated by early (colonial) New World Catholic missionaries since 1959, when my parents first took me to Fort Michilimackinac at the tip of Michigan's Lower Peninsula, then farther north to St. Ignace and Sault Ste. Marie, both in the Upper Peninsula. There, I learned firsthand about the work of the early Jesuit fathers, and their attempts (some successful, some not) to bring Native Americans to Christianity. By the mid-1960s, I had read Vernon Kinietz's book Indian Life in the Upper Great Lakes, 1615-1760 (1965), which further fostered my interest about the assimilation and acculturation process behind culture change. As a budding anthropologist, I read Reuben Thwaites's seventy-three-volume work Jesuit Relations and Allied Documents, 1610-1791 (1853-1915) through my college years at Central Michigan University. Now, added to these noted works, is a new book written by Linda Carol Jones. Jones, an associate professor of language area studies at the University of Arkansas, has further documented the influence of Jesuits from the Great Lakes area into the middle and lower Mississippi River valley. After reading Jones's work, I am confident her book will be considered of equal importance to the writings of Kinietz and Thwaites whenever studies about early colonial Jesuit history of the pays d'en haut are mentioned. Jones details the extraordinary, often reciprocal, and dynamic interactions (both good and bad) among different Native and European groups along the Mississippi River during the colonial (contact period) era. These dynamic cultural interactions might be Natives (various Illini groups and groups located further south along the Mississippi, like the Tamarois, Quapaw, Chickasaw, Natchez, or others) with other Natives; Natives and Europeans—the world of European traders (both French and English), coureurs de bois, and metis—and Europeans with other Europeans (e.g., Jesuits with various political leaders such as Cadillac, Iberville, or Bienville), explorers (e.g., LaSalle and Tonti), religious leaders (whether back in Montreal with the Petit Séminaire de Québec, in Paris, or with the Holy See at the Vatican), or different missionary sects also vying for Native converts to baptize. Indeed, Jones's book details the significant, and extremely complex, ideological and political considerations Jesuit fathers needed to "stay alive" (although martyrdom was not a bad thing if done for the right reasons), and how best to convert Natives to Christianity: force-feeding Christianity and European values to Native Americans in what Jones calls "Frenchification" (that is, forcefully [End Page 151] making Natives French men and women), or finding ways (linguistically or culturally) that Native Americans themselves selected to adopt; that is, letting the choice of acceptance or rejection be a Native one, whether for what the idea was, or a modification of the idea as it would best fit a Native cultural need or understanding. Indeed, when Frenchification was forced on Natives, the results ended in a "shattered cross." Although I considered my background in Jesuit history in North America better than average, I learned so much more about Colonial Jesuit history that I did not know previously, especially regarding the political climate between Jesuits and church leadership (that is, "Jesuits in the field" versus church leadership in Montreal, Paris, or the Vatican). Nor was I aware that the idea to begin missionary work among Native Americans along the Mississippi River had its origin in seventeenth-century Jesuit fathers in China. And although church philosophy in the late 1600s and early 1700s was to force "Frenchification" on the Natives, Jesuits who were the most successful as Christian missionaries were those who practiced love, allowing Natives to accept or reject on their own terms what part of French culture and Catholicism best served their needs. Colonialism, including intentional forms of assimilation, acculturation, and—yes—genocide, is not to be condoned in today's world. But it did happen. Ignoring that it happened presents an incomplete...

Codium-like taxa from the Silurian of North America: morphology, taxonomy, paleoecology, and phylogenetic affinity

AbstractA 1901 report by the Smithsonian Custodian of Paleozoic Plants noted that the nonbiomineralized taxaButhotrephis divaricataWhite, 1901,B. newliniWhite, 1901, andB. lesquereuxiGrote and Pitt, 1876, from the upper Silurian of the Great Lakes area, shared key characteristics in common with the extant green macroalgaCodium. A detailed reexamination of theseCodium-like taxa and similar forms from the lower Silurian of Ontario, New York, and Michigan, including newly collected material ofThalassocystis striataTaggart and Parker, 1976, aided by scanning electron microscopy and stable carbon isotope analysis, provides new data in support of an algal affinity. Crucially, as withCodium, the originally cylindrical axes of all of these taxa consist of a complex internal array of tubes divided into distinct medullary and cortical regions, the medullary tubes being arranged in a manner similar to those of livingPseudocodium. In view of these findings, the three study taxa originally assigned toButhotrephis, together withChondrites verusRuedemann, 1925, are transferred to the new algal taxonInocladusnew genus, thereby establishingInocladus lesquereuxinew combination,Inocladus newlininew comb.,Inocladus divaricatanew comb., andInocladus verusnew comb. Morphological and paleoecological data point to a phylogenetic affinity forInocladusn. gen. andThalassocystiswithin theCodium-bearing green algal order Bryopsidales, but perhaps nested within an extinct lineage. Collectively, this material fits within a large-scale pattern of major macroalgal morphological diversification initiated in concert with the Great Ordovician Biodiversification Event and apparently driven by a marked escalation in grazing pressure.UUID:http://zoobank.org/97c5c737-b291-41a2-aceb-f398cac9537a

Assessing terrestrial wildlife populations in the Toronto and Region Area of Concern

Beneficial use impairments (BUIs) under the Great Lakes Water Quality Agreement identify environmental issues requiring remedial action within the Great Lakes Areas of Concern (AOCs). We conducted this study to support the assessment of the wildlife component of BUI 3: degradation of fish and wildlife populations. We compared bird and amphibian (frogs and toads) data from the Toronto and Region Conservation Authority’s Terrestrial Long-term Monitoring Program in the Toronto and Region AOC to an adjacent, but otherwise similar, reference watershed, Duffins Creek. Twelve of 13 targets were met within the AOC for forest bird, wetland bird, meadow bird and amphibian populations based on averages of mean annual values at sites within the AOC that were within two standard deviations of averages at sites in the Duffins Creek reference watershed between 2008 and 2017. Even though wildlife populations within the AOC were within the normal range of variability expected from a reference watershed, they were often at lower levels than within the Duffins Creek reference watershed. In addition, forest bird and amphibian populations were negatively affected by urbanization within the AOC and meadow bird indices declined. We conclude that while wildlife populations within the AOC currently meet targets for BUI 3, they continue to be negatively impacted by numerous stressors that are primarily related to past and ongoing urbanization. Thus, continued restoration of wildlife habitat and protection of existing habitat within the AOC is highly recommended.

Watershed or bank-to-bank? Scales of governance and the geographic definition of Great Lakes Areas of Concern.

Much recent scholarship has addressed the rise of the watershed as the preferred scale for the governance of water quality. Although the watershed remains widely perceived as an ideal, “natural” scale of freshwater governance, arguments for the merits of alternative scales and multi-scalar approaches are gaining prominence. The Great Lakes Areas of Concern program, managed jointly by the United States and Canada, represents an important case in which the watershed has not prevailed as the default local scale of governance, at least in the 31 Areas of Concern located in the United States or straddling the international border. Based on a review of documents and analysis of a survey and interviews with key actors from local Areas of Concern, we find considerable variation among U.S. states in the designation of Areas of Concern as watersheds and partial watersheds, bank-to-bank watercourse segments, or hybrids of both. This variation depends not only on the differing biophysical conditions at Areas of Concern but also on differences in the latitude that state agencies gave to local stakeholder groups when the geographical extent of each Areas of Concern was designated and negotiated. In several cases, questions about the appropriate scale of the Areas of Concern led to controversy, with implications for subsequent remediation. We contend that understanding the uneven embrace of the watershed as a scale of water governance requires attending not only to specific governance objectives but also to variations in the relationships between local and subnational scales in governance programs.

Perfluoroalkyl Substances in U.S. market basket fish and shellfish

Over the past two decades the class of per- and polyfluoroalkyl substances (PFAS) has emerged as a widespread contaminant in environmental media globally. As awareness and understanding of its prevalence, persistence, and potential health risks grows, so have concerns about human exposure. While drinking water has received substantial attention, dietary intakes have also been reported to contribute significantly to total exposure, with fish consumption in particular. Most studies of U.S. fish have targeted sport fish from areas of known or suspected contamination. This study was undertaken to improve data on PFAS levels in the U.S. commercial seafood supply. A total of 70 samples of finfish and shellfish were purchased at U.S. grocery stores and fish markets and analyzed for 26 PFAS compounds. The samples included a range of marine and freshwater species from four regions of the U.S. and seven countries with significant imports to the U.S. Up to ten PFAS were detected in 21 samples, with PFOS the predominant compound. There were no detections in the remaining 49 samples (detection limits of approximately 0.4–0.5 ppb). Total PFAS concentrations in most samples were single digit or sub-ppb levels. The exception was commercial finfish from the Great Lakes area, for which higher levels (up to 22 ppb) were observed in whitefish, walleye, and yellow perch fillet. Study findings suggest PFAS is present at low or non-detect levels in the U.S. commercial seafood supply and exposure is low for consumers of market basket fish and shellfish.

Speciation and bioavailability of particulate phosphorus in forested karst watersheds of southern Ontario during rain events

Understanding riverine phosphorus (P) dynamics, its transport, and transformation mechanisms from sources in the watersheds to receiving water bodies are essential for the development of effective strategies to decrease excess P loading and reduce eutrophication. Karst watersheds are thought to be especially vulnerable to P pollution due to their geomorphological features. In this study, we investigated the dynamics of particulate P (PP) chemical phases in two karst watersheds from a Great Lakes Area of Concern in southern Ontario (Bay of Quinte, Canada). Suspended solids were collected during different hydrological regimes representing storm events with low and high discharge, and particulate P binding forms were measured using extraction techniques. Our results show that in these karst watersheds, particulate P is dominated by chemical species that are likely to be highly bioavailable and contribute 62–75% to total PP. Concentrations of these bioavailable P binding forms in suspended solids increase two- to three-fold on dry mass basis during periods of high river flow. Electron microprobe and energy dispersive X-ray spectroscopy suggest that the primary carriers of particulate P are aggregates of Fe oxyhydroxides and Al-silicates. Our results underscore the influence of particulate P sources on the ongoing eutrophication in the Bay of Quinte Area of Concern.

Quantifying surface severity of the 2014 and 2015 fires in the Great Slave Lake area of Canada

The focus of this paper was the development of surface organic layer severity maps for the 2014 and 2015 fires in the Great Slave Lake area of the Northwest Territories and Alberta, Canada, using multiple linear regression models generated from pairing field data with Landsat 8 data. Field severity data were collected at 90 sites across the region, together with other site metrics, in order to develop a mapping approach for surface severity, an important metric for assessing carbon loss from fire. The approach utilised a combination of remote sensing indices to build a predictive model of severity that was applied within burn perimeters. Separate models were created for burns in the Shield and Plain ecoregions using spectral data from Landsat 8. The final Shield and Plain models resulted in estimates of surface severity with 0.74 variance explained (R2) for the Plain ecoregions and 0.67 for the Shield. The 2014 fires in the Plain ecoregion were more severe than the 2015 fires and fires in both years in the Shield ecoregion. In further analysis of the field data, an assessment of relationships between surface severity and other site-level severity metrics found mixed results.

Collection of Anthropogenic Litter from the Shores of Lake Malawi: Characterization of Plastic Debris and the Implications of Public Involvement in the African Great Lakes.

Anthropogenic debris is an environmental problem that affects beaches and coastlines worldwide. The abundance of beach debris is often documented with the use of public volunteers. To date, such community participations have been largely confined to the marine environment, but the presence and impact of anthropogenic debris on freshwater shorelines has been increasingly recognized. Our study presents the first such information from the African Great Lakes, specifically Lake Malawi. A total of 490,064 items of anthropogenic litter were collected by over 2000 volunteers in a clean-up campaign that took place annually between 2015 and 2018. Approximately 80% of the anthropogenic debris was comprised of plastic litter, with plastic carrier bags being the most common item. The dominance of plastic litter, and in particular the presence of plastic bags, which have subjected to bans in some African countries, is discussed. The broader implications of citizen science in the African Great Lakes area is also discussed.