scholarly journals Plastic Microbead Accumulation in our Freshwaters: North American Great Lakes Assessments and Perspective

Author(s):  
Mary Torrance ◽  
Emma Gillies ◽  
Tristan Borchers ◽  
Avery Shoemaker ◽  
Christopher Barrett

The authors review recent studies conducted across the Great Lakes of North America to assess the quantity and type of microplastic waste found in these waters, sediments, and beaches. Findings from their own studies are shared, sampling plastic pollution from remote and secluded Nature Reserves in Lake Erie (ON), and the Ottawa River watershed (QC), showing significant accumulation of microbeads. Spherical ‘microbeads’ made of plastics are now ubiquitous in a wide range of personal healthcare and cleansing products, used by the average North American consumer now at upwards of quadrillions per day. Designed to be flushable, these plastic microbeads inevitably end up in municipal wastewater streams, and then to a large extent leak into our freshwater ecosystems. Recent studies throughout the important Great Lakes system of North America have reported microbeads at essentially all locations examined. On the shorelines, in surface waters, throughout water columns, and in sediments of these freshwater systems, microbeads are now ever-present, and are accumulating in significant amounts. Their small and stable shape and composition, and limited pathways to degradation produce a long lifespan, with the capacity to remain in the freshwater environment for potentially hundreds of years. This review collects and compares initial microbead studies between 2013–2021 in the Great Lakes region to provide a snapshot of the current levels and locations, and to serve as a baseline for future tracking to assess progress as the microbead contamination and accumulation problem is addressed. We as well present findings from our own local study of microplastic/bead accumulation downstream of the Great Lakes, in the St. Lawrence and Ottawa rivers near Montreal. Aspects of microbead contamination represent a unique subset of the worldwide microplastic problem, in that much control remains over their life cycle and eventual fate. Consequently, the power to address this microbead problem can rest with polymer chemists and engineers, who, armed with a better understanding of the relevant physical polymer properties of the beads that govern their movement into the aquatic environment, hold the ability to rationally redesign microbead composition and develop removal techniques.

2017 ◽  
Vol 79 (03) ◽  
pp. 289-296 ◽  
Author(s):  
Jamie Van Gompel ◽  
R. Wiet ◽  
Nicole Tombers ◽  
Anand Devaiah ◽  
Devyani Lal ◽  
...  

Background Very few studies have examined vestibular schwannoma (VS) management trends across centers and between providers. The objective of this study is to examine current practice trends, variance in treatment philosophies, and nuanced or controversial aspects of VS care across North America. Methods This is a cross-sectional survey of North American Skull Base Society (NASBS) members who report regular involvement in VS care. Results A total of 57 completed surveys were returned. Most respondents claimed to have over 20 years of experience and the majority reported working in an academic practice with an affiliated otolaryngology and/or neurosurgery residency program. Sixty-three percent of respondents claimed to evaluate VS patients in clinic with both an otolaryngologist and neurosurgeon involved. Eighty-six percent of respondents claimed to operate on VS with both an otolaryngologist and neurosurgeon involved, while only 18% of neurosurgeons and 9% of otolaryngologists performed surgery alone. There was a wide range in the number of cases evaluated at each center annually. Similarly, there was wide variation in the number of patients treated with microsurgery and radiation at each center. Additional details regarding management preferences for microsurgery, stereotactic radiosurgery, stereotactic radiotherapy, and conservative observation are presented. Conclusion VS management practices vary between providers and centers. Overall, most centers employ a multidisciplinary approach to management with collaboration between otolaryngology and neurosurgery. Overall, survey responses concur with previous studies suggesting a shift toward conservatism in management.


2021 ◽  
Vol 23 (5) ◽  
pp. 1563-1576 ◽  
Author(s):  
Phillip J. Haubrock ◽  
Gordon H. Copp ◽  
Iva Johović ◽  
Paride Balzani ◽  
Alberto F. Inghilesi ◽  
...  

AbstractThe North American channel catfish Ictalurus punctatus has been introduced to several locations in Europe but has received little or no scientific study despite its invasive attributes, including prolific reproduction, tolerance to a wide range of conditions, opportunistic feeding, at least partial ‘predator release’, and some evidence of environmental impacts (e.g. disease transmission). To assess the species’ potential invasiveness and the likely risks to native species and ecosystems in Europe, available literature from both North America and Europe was reviewed and used to carry out risk screenings of the species for the risk assessment areas, North and South Italy, using the Aquatic Invasiveness Screening Kit (AS-ISK), which was followed by a more detailed evaluation (for both North America and Europe) of the species’ potential impacts using the Environmental Impact Classification of Alien Taxa (EICAT) assessment protocol. The AS-ISK score indicated that channel catfish is likely to pose a high risk of being invasive in both North and South Italy, with EICAT scores indicating “Major” impacts for both North America and Europe, at high and medium confidence levels, respectively. The present results emphasise the urgent need to carry out in-depth studies on introduced populations of this species to understand better its invasive potential so as to inform management decisions on the appropriate control or eradication measures for invaded water bodies.


2020 ◽  
Vol 11 ◽  
Author(s):  
Fang Wu ◽  
Shou-Jian Li ◽  
Cai-Hong Dong ◽  
Yu-Cheng Dai ◽  
Viktor Papp

The fungus “Fuling” has been used in Chinese traditional medicine for more than 2000 years, and its sclerotia have a wide range of biological activities including antitumour, immunomodulation, anti-inflammation, antioxidation, anti-aging etc. This prized medicinal mushroom also known as “Hoelen” is resurrected from a piece of pre-Linnean scientific literature. Fries treated it as Pachyma hoelen Fr. and mentioned that it was cultivated on pine trees in China. However, this name had been almost forgotten, and Poria cocos (syn. Wolfiporia cocos), originally described from North America, and known as “Tuckahoe” has been applied to “Fuling” in most publications. Although Merrill mentioned a 100 years ago that Asian Pachyma hoelen and North American P. cocos are similar but different, no comprehensive taxonomical studies have been carried out on the East Asian Pachyma hoelen and its related species. Based on phylogenetic analyses and morphological examination on both the sclerotia and the basidiocarps which are very seldomly developed, the East Asian samples of Pachyma hoelen including sclerotia, commercial strains for cultivation and fruiting bodies, nested in a strongly supported, homogeneous lineage which clearly separated from the lineages of North American Wolfiporia cocos and other species. So we confirm that the widely cultivated “Fuling” Pachyma hoelen in East Asia is not conspecific with the North American Wolfiporia cocos. Based on the changes in Art. 59 of the International Code of Nomenclature for algae, fungi, and plants, the generic name Pachyma, which was sanctioned by Fries, has nomenclatural priority (ICN, Art. F.3.1), and this name well represents the economically important stage of the generic type. So we propose to use Pachyma rather than Wolfiporia, and subsequently Pachyma hoelen and Pachyma cocos are the valid names for “Fuling” in East Asia and “Tuckahoe” in North America, respectively. In addition, a new combination, Pachyma pseudococos, is proposed. Furthermore, it seems that Pachyma cocos is a species complex, and that three species exist in North America.


2002 ◽  
Vol 59 (6) ◽  
pp. 1078-1084 ◽  
Author(s):  
Jaimie T.A Dick ◽  
Dirk Platvoet ◽  
David W Kelly

To assess the increasing threats to aquatic ecosystems from invasive species, we need to elucidate the mechanisms of impacts of current and predicted future invaders. Dikerogammarus villosus, a Ponto–Caspian amphipod crustacean, is invading throughout Europe and predicted to invade the North American Great Lakes. European field studies show that populations of macroinvertebrates decline after D. villosus invasion. The mechanism of such impacts has not been addressed empirically; however, D. villosus is known to prey upon and replace other amphipods. Therefore, in this study, we used microcosm and mesocosm laboratory experiments, with both single and mixed prey species scenarios, to assess any predatory impact of D. villosus on a range of macroinvertebrate taxa, trophic groups, and body sizes. Dikerogammarus villosus predatory behaviour included shredding of prey and infliction of "bite" injuries on multiple victims. Dikerogammarus villosus killed significantly greater numbers of macroinvertebrates than did the native Gammarus duebeni, which is currently being replaced by D. villosus. This invader thus appears to impact on freshwater ecosystems through its exceptional predatory capabilities. We predict that future invasions by D. villosus will have serious direct and indirect effects on freshwaters, with its invasion facilitated in a larger "invasional meltdown" in regions like the North American Great Lakes.


Rangifer ◽  
1996 ◽  
Vol 16 (4) ◽  
pp. 7
Author(s):  
Kent Brown et al. (iss. eds.)

The Sixth North American Caribou workshop was attended by over 200 people from across North America, as well as four special guests from Russia. Participants were very surprised to see and hear about caribou living in large cedar forests and on mountain-tops where snow depths exceeded several meters, and the only available forage was the lichens growing on trees. We believe that the workshop was a major success with many excellent presentations and posters, as well as opportunities for the participants to meet and discuss caribou research, ecology, and management with their counterparts from across North America. These proceedings include a wide range of excellent papers that provide a permanent record of the workshop. The editors thank the authors and reviewers for their efforts to produce and review these papers.


1989 ◽  
Vol 67 (11) ◽  
pp. 3134-3152 ◽  
Author(s):  
Clark L. Ovrebo

Fifteen species of Tricholoma, subgenus Tricholoma, section Albidogrisea, are described and illustrated. All species occur in the Great Lakes region and many are distributed elsewhere in eastern North America. Four species are new: Tricholoma argenteum, Tricholoma atrodiscum, Tricholoma insigne, and Tricholoma pullum. Keys are provided to the sections of subg. Tricholoma and to the species and stirpes of sect. Albidogrisea.


Paleobiology ◽  
2017 ◽  
Vol 43 (4) ◽  
pp. 642-655 ◽  
Author(s):  
Meaghan M. Emery-Wetherell ◽  
Brianna K. McHorse ◽  
Edward Byrd Davis

AbstractThe late Pleistocene megafaunal extinctions may have been the first extinctions directly related to human activity, but in North America the close temporal proximity of human arrival and the Younger Dryas climate event has hindered efforts to identify the ultimate extinction cause. Previous work evaluating the roles of climate change and human activity in the North American megafaunal extinction has been stymied by a reliance on geographic binning, yielding contradictory results among researchers. We used a fine-scale geospatial approach in combination with 95 megafaunal last-appearance and 75 human first-appearance radiocarbon dates to evaluate the North American megafaunal extinction. We used kriging to create interpolated first- and last-appearance surfaces from calibrated radiocarbon dates in combination with their geographic autocorrelation. We found substantial evidence for overlap between megafaunal and human populations in many but not all areas, in some cases exceeding 3000 years of predicted overlap. We also found that overlap was highly regional: megafauna had last appearances in Alaska before humans first appeared, but did not have last appearances in the Great Lakes region until several thousand years after the first recorded human appearances. Overlap in the Great Lakes region exceeds uncertainty in radiocarbon measurements or methodological uncertainty and would be even greater with sampling-derived confidence intervals. The kriged maps of last megafaunal occurrence are consistent with climate as a primary driver in some areas, but we cannot eliminate human influence from all regions. The late Pleistocene megafaunal extinction was highly variable in timing and duration of human overlap across the continent, and future analyses should take these regional trends into account.


1858 ◽  
Vol 2 ◽  
pp. 203-212
Author(s):  
Daniel Wilson ◽  
Robert Chambers

The author, having visited North America, describes the copper deposits found on the shores of the Great Lakes and the techniques used by the native peoples of these regions to work this metal into tools and weaponry. He also discusses the discovery of tropical conch shells in this area and the burial practices of some of the native peoples. It is noted that the native Americans hammered the copper into shape while it was cold as they did not use smelting. He concludes by contrasting the geographical factors that he believes affected European and North American history and making some generalisations about the racial characteristics of European and native American peoples.


1994 ◽  
Vol 126 (1) ◽  
pp. 135-181 ◽  
Author(s):  
D.J. Larson

AbstractSpecies of Agabus of the lutosus-, obsoletus-, and fuscipennis-groups, as defined by Larson (1989), are revised. Members of the lutosus- and obsoletus-groups are restricted to the Cordilleran and Great Plains regions of temperate western North America. Within this region, the species of each group are largely parapatric. Three species are assigned to the lutosus-group: A. lutosus LeConte along the Pacific Coast; A. griseipennis LeConte in the Great Basin, Rocky Mountain, and Great Plains regions; and A. rumppi Leech in the southern deserts. Agabus lutosus and A. griseipennis hybridize in the Pacific Northwest; A. lutosus mimus Leech is synonymized with A. lutosus. The obsoletus-group contains five species: A. obsoletus LeConte, A. morosus LeConte, and A. ancillus Fall along the Pacific Coast and the Sierra Nevada Mountains; A. hoppingi Leech in the Sierra Nevada Mountains; and A. obliteratus LeConte, containing two subspecies, A. o. obliteratus and A. o. nectris Leech, new status, with a wide range including the Great Plains and Cordillera but not reaching the Pacific Coast. The four species of the fuscipennis-group, A. ajax Fall, A. coxalis Sharp, A. fuscipennis (Paykull), and A. infuscatus Aubé, are boreal and all except A. ajax are Holarctic. Agabus coxalis is restricted to northwestern North America, the other three species are transcontinental.For each species the following information is provided: synonymy, description, and illustrations of taxonomically important characters; notes on relationships, variation, distribution, and ecology; and a map of North American collection localities. Group diagnoses and keys to the species of each group are presented. A correction to the key to species groups of North American Agabus (Larson 1989) is made with the addition of a couplet to include the obsoletus-group. Lectotypes are designated for A. discolor LeConte and A. obliteratus LeConte.


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