36 research outputs found

    The use of biochar and pyrolysed materials to improve water quality through microcystin sorption separation

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    Unidad de excelencia María de Maeztu CEX2019-000940-MHarmful algal blooms have increased globally with warming of aquatic environments and increased eutrophication. Proliferation of cyanobacteria (blue-green algae) and the subsequent flux of toxic extracellular microcystins present threats to public and ecosystem health and challenges for remediation and management. Although methods exist, there is currently a need for more environmentally friendly and economically and technologically feasible sorbents. Biochar has been proposed in this regard because of its high porosity, chemical stability, and notable sorption efficiency for removing of cyanotoxins. In light of worsening cyanobacterial blooms and recent research advances, this review provides a timely assessment of microcystin removal strategies focusing on the most pertinent chemical and physical sorbent properties responsible for effective removal of various pollutants from wastewater, liquid wastes, and aqueous solutions. The pyrolysis process is then evaluated for the first time as a method for sorbent production for microcystin removal, considering the suitability and sorption efficiencies of pyrolysed materials and biochar. Inefficiencies and high costs of conventional methods can be avoided through the use of pyrolysis. The significant potential of biochar for microcystin removal is determined by feedstock type, pyrolysis conditions, and the physiochemical properties produced. This review informs future research and development of pyrolysed materials for the treatment of microcystin contaminated aquatic environments

    Preparation and characterization of novel magnesium composite/walnut shells-derived biochar for as and p sorption from aqueous solutions

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    Unidad de excelencia María de Maeztu CEX2019-000940-MElevated or unnatural levels of arsenic (As) and phosphorus (P) concentrations in soils and waterbodies from anthropogenic sources can present significant hazards for both natural ecosystems and human food production. Effective, environmentally friendly, and inexpensive materials, such as biochar, are needed to reduce mobility and bioavailability of As and P. While biochar features several physicochemical properties that make it an ideal contaminant sorbent, certain modifications such as mineral-impregnation can improve sorption efficiencies for targeted compounds. Here, we conducted sorption experiments to investigate and quantify the potential utility of magnesium (Mg) for improving biochar sorption efficiency of P and As. We synthesized a Mg-modified walnut shells-derived biochar and characterized its ability to remove As and P from aqueous solutions, thereby mitigating losses of valuable P when needed while, at the same time, immobilizing hazardous As in ecosystems. SEM-EDX, FTIR and elemental analysis showed morphological and functional changes of biochar and the formation of new Mg-based composites (MgO, MgOHCl) responsible for improved sorption potential capacity by 10 times for As and 20 times for P. Sorption efficiency was attributed to improved AEC, higher SSA, chemical forms of sorbates and new sorption site formations. Synthetized Mg-composite/walnut shell-derived biochar also removed >90% of P from real samples of wastewater, indicating its potential suitability for contaminated waterbody remediation

    Identifying invasive species threats, pathways, and impacts to improve biosecurity

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    Managing invasive species with prevention and early-detection strategies can avert severe ecological and economic impacts. Horizon scanning, an evidence-based process combining risk screening and consensus building to identify threats, has become a valuable tool for prioritizing invasive species management and prevention. We assembled a working group of experts from academic, government, and nonprofit agencies and organizations, and conducted a multi-taxa horizon scan for Florida, USA, the first of its kind in North America. Our primary objectives were to identify high-risk species and their introduction pathways, to detail the magnitude and mechanism of potential impacts, and, more broadly, to demonstrate the utility of horizon scanning. As a means to facilitate future horizon scans, we document the process used to generate the list of taxa for screening. We evaluated 460 taxa for their potential to arrive, establish, and cause negative ecological and socioeconomic impacts, and identified 40 potential invaders, including alewife, zebra mussel, crab-eating macaque, and red swamp crayfish. Vertebrates and aquatic invertebrates posed the greatest invasion threat, over half of the high-risk taxa were omnivores, and there was high confidence in the scoring of high-risk taxa. Common arrival pathways were ballast water, biofouling of vessels, and escape from the pet/aquarium/horticulture trade. Competition, predation, and damage to agriculture/forestry/aquaculture were common impact mechanisms. We recommend full risk analysis for the high-risk taxa; increased surveillance at Florida's ports, state borders, and high-risk pathways; and periodic review and revision of the list. Few horizon scans detail the comprehensive methodology (including list-building), certainty estimates for all scoring categories and the final score, detailed pathways, and the magnitude and mechanism of impact. Providing this information can further inform prevention efforts and can be efficiently replicated in other regions. Moreover, harmonizing methodology can facilitate data sharing and enhance interpretation of results for stakeholders and the general public.</p

    The use of biochar and pyrolysed materials to improve water quality through microcystin sorption separation

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    Unidad de excelencia María de Maeztu CEX2019-000940-MHarmful algal blooms have increased globally with warming of aquatic environments and increased eutrophication. Proliferation of cyanobacteria (blue-green algae) and the subsequent flux of toxic extracellular microcystins present threats to public and ecosystem health and challenges for remediation and management. Although methods exist, there is currently a need for more environmentally friendly and economically and technologically feasible sorbents. Biochar has been proposed in this regard because of its high porosity, chemical stability, and notable sorption efficiency for removing of cyanotoxins. In light of worsening cyanobacterial blooms and recent research advances, this review provides a timely assessment of microcystin removal strategies focusing on the most pertinent chemical and physical sorbent properties responsible for effective removal of various pollutants from wastewater, liquid wastes, and aqueous solutions. The pyrolysis process is then evaluated for the first time as a method for sorbent production for microcystin removal, considering the suitability and sorption efficiencies of pyrolysed materials and biochar. Inefficiencies and high costs of conventional methods can be avoided through the use of pyrolysis. The significant potential of biochar for microcystin removal is determined by feedstock type, pyrolysis conditions, and the physiochemical properties produced. This review informs future research and development of pyrolysed materials for the treatment of microcystin contaminated aquatic environments

    The Effects of Algaecides and Herbicides on a Nuisance <i>Microcystis wesenbergii</i>-Dominated Bloom

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    Microcystis-dominated cyanobacterial harmful algal blooms (cyanoHABs) are a reoccurring problem globally, resulting in widespread economic and health impacts. As public awareness of the risks of blooms increases, there is an urgent need for studies on both short-term and long-term management of cyanoHABs. In order to provide science-based best management practices and treatment options, we tested various concentrations and combinations of USEPA-registered algaecides and herbicides on a Microcystis wesenbergii-dominated bloom. The bloom material was exposed to fifteen different algaecides, herbicides, or combinations, using four different concentrations. Cell abundance and morphology as well as microscopic analyses were undertaken at the time of collection and 72 h post-treatment. Overall, the effectiveness of the chemicals varied with the most efficacious treatments being SeClear®, and a combination of Hydrothol® 191 and GreenClean® Liquid 5.0, both of which resulted in a significant decrease at all tested concentrations after 72 h. Interestingly, Microcystis wesenbergii is more resistant to algaecides than M. aeruginosa. Results from this study provide valuable data for treating cyanoHABs and show the varied efficacy of different algaecidal formulations

    The ‘cyanobiome’ of Svalbard, High Arctic

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    Over the last decades, the Arctic has experienced a warming trend that is nearly twice as high as the global average, a phenomenon known as ‘Arctic amplification’. The impact of warmer temperatures on Arctic ecosystems is still unclear. Cyanobacteria are the key primary producers in freshwater and terrestrial Arctic ecosystems, where they are the driver for numerous ecological functions. For a better understanding of the impacts of climate change on Arctic ecosystems, baseline knowledge on cyanobacterial diversity and distribution is crucial. Here we investigate, for the first time, the biogeographic patterns of cyanobacterial communities across Svalbard, using 454 pyrosequencing of partial 16S rRNA gene sequences. Samples were taken from distinct ecosystems and biogeographic zones. We also compare the studied communities with similar Antarctic communities.Cyanobacterial diversity in Svalbar

    OG# to Protein List

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    An excel file listing the protein name, abbreviation, found KEGG function (if known), and the corresponding OG5 number of the alignment for all 58 presence/absence lateral gene transfers found. Each animo acid sequence alignment file is labeled with a unique OG5#
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