Aquatic Ecosystems Research Articles

Sterilization mechanism of CuCeOx on fungus: Oxidative damage and energy metabolism disequilibrium

Pathogens in bioaerosols and aquatic environment cause epidemic outbreak frequently. Relative to bacteria and virus, fungi has not received attention enough. The development of sterilization materials and mechanism on fungi are limited. In this study, we proposed a non-noble metal sterilization material CuCeOx in order to investigate its sterilization mechanism on target fungal Hanseniaspora uvarum collected from the air. The active components of CuCeOx were uniformly distributed and induced the production of R·. The reactive oxygen species (ROS) changed from R· to RO· upon contact with fungal cells. Transcriptomics identified 1665 Differentially Expressed Genes (DEGs), including 1540 up-regulated and 125 down-regulated genes. The cell wall and external encapsulation structure were firstly damaged when the fungus contacted with CuCeOx, and the related DEGs were significantly down-regulated. CuCeOx could exert great impact on the energy metabolism of the cell, especially on the process of oxidative phosphorylation, which contained 59 up-regulated and 2 down-regulated genes. The cell is not sufficient to cope with the adverse environment caused by oxidative stress and metal ion homeostatic imbalance, which then modulates the intrinsic apoptotic pathway triggering apoptosis.

Ecotoxicological effects of pharmaceutical preparations and the possibility of removing them through phytoremediation: A review

From several decades, there was a significant increase in the production of pharmaceuticals due to their widespread use for both animal and human health. However, these pharmaceuticals also release large amounts of waste into the water environment, where they have been found at levels of ng/l to mg/l in wastewater and surface water. Additionally, because pharmaceuticals initially have biological effects such endocrine disruption, they may have a multitude of adverse effects. Hospitals are indicated or thought to be a significant and extremely variable source that is typically released into sewers immediately, without any kind of preparation. even if they only make up a minor portion of the influents of sewage treatment plants' overall effluent volume. One of the primary sources of pharmaceuticals that are present in every area of the environment is the hospitals. These medications were transferred to wastewater treatment plants (WWTPs), which lack the necessary equipment to effectively handle these kinds of substances. Pharmaceutical contamination of water is regarded as a growing pollution issue in developed nations as these pollutants and micropollutants have been introduced into drinking water sources. In order to raise awareness among physicians, patients, and pharmaceutical manufacturers that pharmaceutical materials may have side effects outside of the patient, certain countries have implemented a classification system for pharmaceutical drugs based on their propensity to accumulate in surface water and interfere with aquatic life. This program is assessed by yearly tests of pharmaceuticals in sewage treatment effluents. The results indicate the presence of numerous types of medicines, including trimethoprim, sulfamethoxazole, and metronidazole, in all analyzed sewer treatment plant effluents. The manufacturing and consumption of pharmaceuticals appear to have an impact on their presence in wastewater.

Public preferences for edible invasive alien marine species - The Atlantic blue crab in southern Italy

Since 2014, the provision of the aquatic ecosystem services has been gradually affected due to the biological invasion of Callinectes sapidus (Rathbun, 1896, Crustacea, Decapoda, Portunidae), commonly known as Atlantic blue crab, across several lagoon-like locations in Italy. In addition, this serious aquatic invasive species, native of North American coasts, has already inflicted economic damage of about EUR 100 million to the Italian fishing and farming communities over the past year. To counter their severe and rapid spread, the Italian Government has encouraged the fishing communities to catch as many as possible and commercially exploit them for human consumption in an attempt to manage their expansion. Since there is an ongoing promotion for the consumption of blue crab by forging novel food businesses in Italy, this paper aims to predict the public preferences and their willingness to pay (WTP) towards this biological invader. For this purpose, a discrete choice experiment approach is used, by means of a multinomial logit model (MNL) and latent class model (LCM). The social field survey involves a representative sample of 440 valid respondents in Apulia Region, southern Italy. The descriptive statistics results reveal that 67.50% of the local citizens interviewed know about the blue crab invasion, while 29.09% of them have already consumed this seafood species. In addition, the MNL results show that the most appreciated attributes of the blue crabs by respondents are freshness and large size. Further, the LCM findings reveal two representative classes of Apulian consumers; the first group of citizens (70.9% of total respondents) expresses positive appreciation for consuming blue crabs, while the second group (29.1% of total respondents) is not willing to pay a premium price regarding this potential commercial activity. Furthermore, the econometric results show that the average value that Apulian’s (i.e. those belonging to Class/Group I of respondents) WTP for blue crabs’ consumption is about EUR 18 per kilogram. In this regard, this research has public and private implications and may reasonably promote the commercial exploitation of blue crabs, enhancing the reduction of its population density through human consumption as a promised management control strategy and forging a novel profitable business mainly for local small-scale artisanal fisheries.

Performance of carbon felt as cathodes in magnesium corrosion method to recover phosphate from swine wastewater

With the large-scale development of the livestock and poultry breeding industries, swine wastewater with high nitrogen and phosphorus concentrations has become an urgent problem. Given the continuous demand for phosphorus resources in industrial production, the study of phosphate recovery in phosphorus-rich wastewater is of great value for the sustainable utilization of phosphorus resources and for alleviating the eutrophication of aquatic ecosystems. In this study, a magnesium metal corrosion method was used to recover phosphorus resources from swine wastewater using carbon felt as the cathode instead of traditional cathode materials such as graphite and titanium plates. The effects of different cathode materials on the corrosion potential of magnesium metal plates were compared, and the effects of carbon felt as a cathode plate on the removal rate and pH of phosphate from wastewater were discussed. Additionally, the economic feasibility of phosphate recovery from swine wastewater was evaluated. The experimental results showed that the effect of carbon felt on the corrosion potential of the magnesium metal plate was more evident than that of the graphite and titanium plates (Ecorr = −1.74676). When carbon felt was used as the cathode plate, the most energy-saving reaction conditions were as follows: reaction time T = 30 min, ratio of wastewater volume to plate area V: S = 500 cm3:50 cm2, aeration rate Re = 8 L/min, stirring rate r = 400 rpm, phosphate recovery rate = 92.3%, and pH = 8.83. The economic feasibility assessment shows that the proposed method is $2.047 g-1 PO4-P without considering the reuse of carbon felt. Carbon felt has good stability and can be recycled eight times or more, and the proposed method achieves a more efficient phosphate recovery rate at a relatively low cost.

Toxicological impacts of plastic microfibers from face masks on Artemia salina: An environmental assessment using Box-Behnken design

An increase in global plastic manufacturing and subsequent disposal has resulted in widespread increase in microplastic pollution. Particularly, the post-COVID surge in face mask usage has introduced significant volumes of synthetic plastic microfibers into the environment, posing new ecological risks. Present study examines the toxicological impacts of face mask derived microfibers on Artemia salina, a key marine zooplankton species, using the Box-Behnken design to assess the effects of microfiber dosage (0.1 mg/L- 5 mg/L), salinity (0.5 ppt–30 ppt), temperature (10 °C-45 °C), and cyst stocking density (10 cysts/L-100 cysts/L) on hatching efficiency and swimming competencies. Results demonstrated that higher microfiber dosages (2.5 mg/L-5 mg/L) significantly reduced the hatching efficiencies and swimming competencies, while temperature and cyst density also modulated these effects. Additionally, survival assays indicated a significant reduction in survival rates with increasing microfiber concentrations, attributed to the bioaccumulation, oxidative stress and developmental deformities in the organism. The study further explores the leaching of chromophoric dissolved organic matter and turbidity, revealing a direct correlation with microfiber dosage and exposure duration. These findings underscore the urgent need for mitigation strategies to address microfiber pollution and protect aquatic ecosystems. Data presented from the research provides valuable insights into the environmental impacts of plastic microfiber contamination, emphasizing the necessity for continued investigation into effective solutions for managing plastic waste.

Solar powered integrated multi sensors to monitor inland lake water quality using statistical data fusion technique with Kalman filter

This study proposes a data-driven statistical model using multi sensor fusion and Kalman filtering for real-time water quality assessment in lakes. A recursive estimation technique, the Kalman Filter, is employed to handle uncertainties and enhance computational efficiency. The fusion process integrates data from sensors monitoring parameters like chlorophyll concentration, surface water elevation, temperature, and precipitation, producing Markov features to capture temporal transitions and environmental dynamics. Data synchronization and fusion are achieved through recursive KF methods, enabling real-time adaptive management in response to environmental fluctuations such as seasonal changes, precipitation (6–18%), and evaporation rates (1.2–11.9 mm/day). Over a 30-day evaluation period, the model accurately predicted chlorophyll concentrations, reaching 128 mg/m3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {mg}/\\hbox {m}^{3}$$\\end{document} in mid-level inflow regions (3.6 m water elevation) compared to 86 mg/m3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {mg}/\\hbox {m}^{3}$$\\end{document} in extreme inflow areas (5.5 m). The integration of Markov feature extraction and eigenvalue estimation enhanced prediction stability and sensitivity, with the KF maintaining computational efficiency at 7.8 ms per computation cycle. The model’s accuracy was validated by achieving a residual error of less than 0.05 with minimal noise interference. Overall, the system provides a resilient and precise framework for real-time lake water quality assessment, capable of handling multi-parameter uncertainties and dynamic environmental changes, thereby supporting informed decision-making for aquatic ecosystem management.

Surface microlayer-mediated virome dissemination in the Central Arctic

BackgroundAquatic viruses act as key players in shaping microbial communities. In polar environments, they face significant challenges such as limited host availability and harsh conditions. However, due to the restricted accessibility of these ecosystems, our understanding of viral diversity, abundance, adaptations, and host interactions remains limited.ResultsTo fill this knowledge gap, we studied viruses from atmosphere-close aquatic ecosystems in the Central Arctic and Northern Greenland. Aquatic samples for virus-host analysis were collected from ~60 cm depth and the submillimeter surface microlayer (SML) during the Synoptic Arctic Survey 2021 on icebreaker Oden in the Arctic summer. Water was sampled from a melt pond and open water before undergoing size-fractioned filtration, followed by genome-resolved metagenomic and cultivation investigations. The prokaryotic diversity in the melt pond was considerably lower compared to that of open water. The melt pond was dominated by a Flavobacterium sp. and Aquiluna sp., the latter having a relatively small genome size of 1.2 Mb and the metabolic potential to generate ATP using the phosphate acetyltransferase-acetate kinase pathway. Viral diversity on the host fraction (0.2–5 µm) of the melt pond was strikingly limited compared to that of open water. From the 1154 viral operational taxonomic units (vOTUs), of which two-thirds were predicted bacteriophages, 17.2% encoded for auxiliary metabolic genes (AMGs) with metabolic functions. Some AMGs like glycerol-3-phosphate cytidylyltransferase and ice-binding like proteins might serve to provide cryoprotection for the host. Prophages were often associated with SML genomes, and two active prophages of new viral genera from the Arctic SML strain Leeuwenhoekiella aequorea Arc30 were induced. We found evidence that vOTU abundance in the SML compared to that of ~60 cm depth was more positively correlated with the distribution of a vOTU across five different Arctic stations.ConclusionsThe results indicate that viruses employ elaborate strategies to endure in extreme, host-limited environments. Moreover, our observations suggest that the immediate air-sea interface serves as a platform for viral distribution in the Central Arctic.Dvb_jZZ1H7pg55rxrDSVb2Video

Impact of emerging pollutants mixtures on marine and brackish phytoplankton: diatom Phaeodactylum tricornutum and cyanobacterium Microcystis aeruginosa

Pharmaceuticals and ionic liquids (ILs) are emerging as significant micropollutants with environmental presence and potential ecological impacts. The possible simultaneous occurrence of these two groups of pollutants in aquatic environments raises complex challenges due to their diverse chemical properties and potential for interactive effects. Given the documented widespread presence of pharmaceuticals and the emerging concerns about ILs, the study aims to evaluate the adverse effects of binary mixtures of imidazolium ionic liquid IM1-8C(CN)3 and two representatives of pharmaceuticals: antibiotic oxytetracycline (OXTC) and metabolite carbamazepine 10,11 epoxide (CBZ-E) on the brackish cyanobacterium Microcystis aeruginosa and the marine diatom Phaeodactylum tricornutum during chronic exposure experiments. A comprehensive approach was employed, incorporating various endpoints including oxidative stress, chlorophyll a fluorescence, detailed photoprotective and photosynthetic pigment profiles of target microorganisms to assess modes of action and identify the mixture effects of the selected substances.The observed alterations in pigment production affecting carotenoids synthesis in both selected species may be attributed to the differential impacts of these substances on the photosynthetic pathways and metabolic processes in the cyanobacterial and diatom cells. Changes in chlorophyll a fluorescence-specific parameters suggest impairment of the photosynthetic activity, particularly affecting the efficiency of photosystem II.The application of Concentration Addition (CA) and Independent Action (IA) mathematical models, complemented by the evaluation of Model Deviation Ratios (MDR), revealed predominantly antagonistic interactions within the studied mixtures. The findings of this study provide important insights into the effects of mixtures of organic micropollutants and their potential impact on environment including brackish and marine waters.

Origin and evolution of the blue light receptor cryptochromes (CRY1/2) in aquatic angiosperms.

Cryptochromes (CRYs), which are responsible for sensing blue light in plants, play a critical role in regulating blue light signals and circadian rhythms. However, their functions extend beyond light detection, as they also aid plants in adapting to stress and potentially other regulatory mechanisms. Aquatic angiosperms, which independently evolved from various angiosperm lineages, have developed specific adaptations to unique light qualities and environmental stressors found in aquatic habitats compared to terrestrial ones. It was hypothesized that the sequences and regulatory networks of angiosperm CRY1/2 underwent adaptive evolution in different aquatic angiosperm lineages. To test this hypothesis, we compiled comprehensive datasets consisting of 55 green plant genomes (including 37 angiosperm genomes), 80 angiosperm transcriptomes, and 4 angiosperm expression networks. Through comparative analysis, we found that CRY1 originated from a common ancestor of seed plants, whereas CRY2 originated from a common ancestor of land plants. In angiosperms, the CRY1/2 sequences of aquatic lineages exhibited positive selection, and the conserved valine-proline (VP) motif of CRY2 showed a convergent loss in two aquatic species. Co-expressed genes associated with blue light receptors (CRY) showed adaptations to aquatic environments, specifically in relation to flooding and osmotic stress. These discoveries shed light on the adaptive evolution of CRY1/2, encompassing their origins, sequences, and regulatory networks. Furthermore, these results provide valuable insights for investigating the uncharacterized functions and regulatory pathways of CRY and offer potential targets for enhancing growth and adaptation in agricultural plants.

Ketone body oxidation and susceptibility to ethyl acetoacetate in a novel hemolytic multidrug-resistant strain Leptospira interrogans KeTo originated from sewage water

Terrestrial and aquatic environments contaminated with animal urine may contribute to the transmission of Leptospira, a causative agent of leptospirosis in humans and wild/domesticated animals. Although enormous amounts of work have been done decoding the ecophysiology, the factors governing the cell growth and virulence in Leptospires derived from environmental samples still remain elusive. Here, we show oxidation of a wide array of organic acids including acetoacetate by a new strain of Leptospira interrogans designated as KeTo, isolated from a sewage sample originating from a wildlife enclosure located at Mangalore, India. We further demonstrate the susceptibility of KeTo to ethyl ester of acetoacetate (ethyl acetoacetate, EA). A 4.7 Mbp genome of KeTo shared the highest relatedness to pathogenic L. interrogans RGAT (99.3%), followed by L. kirschneri 3522CT (91.3%) and other related species of Leptospira (80.8‒74.3%), and harbored genes encoding acetoacetyl-CoA synthetase and acetoacetate decarboxylase respectively involved in the acetoacetate utilization and acetone formation. In line with this, strain KeTo oxidized acetoacetate when supplied as a sole carbon. Aqueous EA suppressed biofilm formation (p < 0.0001) of KeTo in basal Ellinghausen–McCullough–Johnson–Harris (EMJH) medium. Similarly, significant inhibition in the growth/biofilm of Leptospira was recorded in semisolid EMJH with/without blood supplementation when exposed to volatile EA. The extent of ketone body oxidation and susceptibility to EA was found to vary with strain as evident through the analysis of L. interrogans serogroup Australis sv. Australis strain Ballico and L. interrogans serogroup Icterohaemorrhagiae sv. Lai Like strain AF61. In conclusion, our study demonstrated the ketone body metabolic ability and susceptibility to an esterified derivative of a major ketone body in the tested strains of L. interrogans. Molecular aspects governing EA-driven growth inhibition warrant further investigations to develop optimal therapeutics for leptospirosis.

Exploring the Potential of Fungal Biomass for Bisphenol A Removal in Aquatic Environments

Bisphenol A is a plastic component, which shows endocrine activity that is detrimental to humans and aquatic ecosystems. The elimination of BPA from the environment is one of the solutions for BPA contaminant management. Adsorption is a cost-effective, easy-to-use method generating low harmful byproducts; nevertheless, contaminant sorbent treatment is a challenge that still needs to be addressed. Fungal fruiting bodies biomass is rarely studied sorbent but is promising due to its high polysaccharide content and availability. Our preliminary studies showed BPA sorption (100 mg/L) by 50 cultivated and wild fungi. The cultivated species: Clitocybe maxima (82%), Pholiota nameko (77%), and Pleurotus columbinus (74%), and wild fungi Cantharellus cibarius (75%) and Lactarius deliciosus (72%) were the most efficient. The biomass was able to sorb BPA over a broad range of temperature and pH levels, with an optimum at 20 °C and pH 7. Although saturation of sorbents was rapid, the regeneration process using ethanol was effective and allowed to recover up to 75% of sorbents’ initial efficiency. A single use of 1 g of sorbent would allow the treatment of 8.86 to 10.1 m3 of wastewater effluent, 16.5 to 18.7 m3 of surface water, and 411 to 469 m3 of drinking water, assuming the concentrations of BPA reported in the literature.

Behavioral and biochemical effects of environmental concentrations of caffeine in zebrafish after long-term exposure

Caffeine (CAF) is widely detected in aquatic environments, serving as an indicator of anthropogenic contamination. Its high consumption, and persistence raise environmental concerns. This study was to evaluate the chronic effects in terms of growth rate, weight, behavior, and biochemical parameters of environmental concentrations of CAF on adult zebrafish. Adult zebrafish were exposed, for 30 d, to 0, 0.5, 1.5, and 300 µg L−1 CAF, with behavior (feeding latency, exploration, aggression, sociability, sound response) and biochemical endpoints (acetylcholinesterase (AChE), lactate dehydrogenase (LDH), and cortisol levels) assessed at the end of the exposure. CAF 0.5 µg L−1 increased feeding latency time, while 300 µg L−1 reduced growth and weight. Exposure to CAF affect fish behavior in terms of vertical exploration, aggressiveness, shoaling, and sound responses although were concentration specific. All concentrations tested increased social behavior, with fish swimming closer to the shoal. At a biochemical level, CAF exposed showed reduced AChE activity, while LDH activity, and cortisol levels increased at 300 µg L−1. Low concentrations of CAF caused neurotoxicity in zebrafish which may compromise their feeding behavior, and social interactions in the wild. These changes suggest potential ecological impacts of chronic exposure to CAF, such as impaired feeding and stress responses.

Remote Sensing Evaluation of Trophic Status in the Daihai Lake Based on Fuzzy Classification

Trophic state index (TSI) is a critical ecological and environmental issue in water resource management that has garnered significant attention. Given the complexity of optical characteristics in aquatic environments, this study employs fuzzy classification methods (FCM) and composite nutrient status indices to meticulously classify in-situ remote sensing reflectance data, aiming to develop evaluation models for different nutrient status categories to facilitate the assessment of the Daihai River in Inner Mongolia, China. Subsequently, we applied this model to MSI data to analyze the nutrient status of Daihai Lake from 2016 to 2021. Furthermore, a structural equation model (SEM) was utilized to explore the primary driving factors influencing nutrient status. The results indicated that the water bodies in Daihai Lake can be broadly classified into three categories, with the nutrient status models demonstrating robust performance for each category (R2 = 0.80, R2 = 0.83, and R2 = 0.74). Comparisons were made between nutrient status accuracies obtained through the NCM and FCM based on measured data, yielding R2 values of 0.74 and 0.85, respectively. Furthermore, the TSI results derived from MSI inversion were validated, with NCM achieving an R2 of 0.49, RMSE of 6.88, and MAPE of 10.36%, while FCM exhibited an R2 of 0.55, RMSE of 8.89, and MAPE of 13.18%. An SEM–based analysis revealed that over the long term, human activities exerted a more substantial impact on eutrophication in Daihai Lake, while climatic factors played an accelerating and reinforcing role. These results are consistent with prior research in the Daihai area, indicating a state of mild eutrophication and the potential of the fuzzy classification method and comprehensive trophic status index method in eutrophication assessment.

A Novel BiOBr/CAU-17 Composite with Enhanced Photo-Catalytic Performance for Dye Degradation and Removal of Tetracycline Antibiotic Under Visible Light.

In order to improve the low specific surface area and high recombinant light generation carriers of BiOBr, loading BiOBr onto suitable Metal Organic Frameworks (MOFs) is an effective strategy to unleash its efficient visible light response and intrinsic catalytic activity. In this study, using classic MOF CAU-17 as a precursor, using a straightforward co-precipitation technique, four BiOBr/CAU-17 composites with distinct MOF contents values BCAU-1, BCAU-2, BC, AU-3, and BCAU-4 were created, and their photo-catalytic characteristics were examined. The BCAU-2 composite exhibited much higher photo-catalytic degradation efficiency for Rhodamine B (RhB) and Tetracycline (TC) than the pristine materials, counter compositions, and early reported materials. XRD, SEM, TEM, XPS, and EDX results revealed the strong synergistic photo-catalytic effect of BiOBr and CAU-17. The photocatalytic degradation of TC was significantly enhanced by the BiOBr bimetal modification, with the 2 wt.% BiOBr/CAU-17 nanocomposite achieving an 87.2 % degradation of TC and 82 % Total Organic Carbon (TOC) removal within 60 min. The high photo-degradation efficiency of BCAU-2 composite should be attributed to the efficient transfer of photo-generated carriers at interfaces and the synergistic effect between BiOBr/CAU-17. Furthermore, the experiments on the capture of the active species proved that the main active free radicals involved in the degradation of RhB and TC are attributed to the photo-induced holes h+ and ⋅ O2 - under visible light. The catalyst's efficacy is corroborated by the outcomes of photoluminescence spectroscopy and photo current response. This study offers a new understanding for the design of green synthesis schemes for photo-catalytic dye degradation and removal of certain antibiotics from the aquatic environment.

Toxic Effect of Heavy Metal Poisoning on Living Organisms in Water and Health Risk: A Central India Study

The main causes of this environmental catastrophe are pollutants such as iron, zinc, lead, nickel, and chromium that have entered the water system as a result of uncontrolled industrial effluent discharge in the area. This study finds resistant bacteria and shows the toxicity of heavy metals in industrial effluent near the steel industry. Five separate locations were used for water sampling, and 16s RNA sequencing of the microorganisms that were found was done along with physicochemical parameter analysis and atomic absorption spectrophotometer use. Different water samples’ conductivity, TDS, salinity, DO, turbidity, and pH levels indicate changes in the quality of the water. In addition to having higher values for each of these characteristics, Sample D3’s water samples had greater concentrations of heavy metals, suggesting contamination. Aspergillus niger and Aspergillus terreus were identified in all samples. Both Gram-negative and Gram-positive Bacilli’s resistance to heavy metals has been found to be a sign of microbial adaptation to exposure to heavy metals. 16s rRNA sequencing of microorganisms revealed their roles in heavy metal bioremediation processes. The delicate balance between the flora and fauna in the affected water bodies has been upset by the devastating losses in aquatic life. In this study, we presented the biological methods for eliminating heavy metals, which comprised both metabolically dependent and independent techniques.

EDNA-Based Survey of Fish Species in Water Bodies Using Loop-Mediated Isothermal Amplification (LAMP) for Application of Developing Automatic Sampler.

The monitoring of species in a habitat is important to ensure biological diversity. Environmental DNA (eDNA) can infer the presence-absence of species and enable rapid action to avoid threatening factors in ecosystems in the case of non-indigenous species. Loop-mediated isothermal amplification (LAMP) assays for molecular amplification are rapidly gaining popularity in species detection, but LAMP remains an underutilized method for eDNA-based monitoring practices. The most effective combination for successful species monitoring may be the collection of eDNA or biological traces collected by nanofiltration followed by LAMP-based species detection initiatives. Here, we used LAMP analysis to detect the eDNA of Esox lucius (Northern Pike), Anguilla anguilla (European Eel), and Salmo salar (Atlantic Salmon) in Borre Lake and in the Drammen River. The selection of species is based on the categories of regionally invasive species, endangered species, and species of least concern. Two target genes were considered for each species and LAMP primers were designed. Our study showed that LAMP is an effective tool for discovering specific fish eDNA (analysis) to maintain aquatic ecosystems.

Rice Response to Struvite and Other Phosphorus Fertilizers in a Phosphorus-Deficient Soil Under Simulated Furrow-irrigation

AbstractWastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to decreasing rock-phosphate reserves. Struvite can be generated via precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice (Oryza sativa) cultivar grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)]. Rice was grown in tubs in controlled environmental conditions in a greenhouse for a full growing season in a P-deficient, silt-loam soil (Typic Glossaqualfs). Plant nutrients (i.e., N. P. K. Mg, Zn) were determined at the end of the growing season through Mehlich-3 extraction. Below- and aboveground rice dry matter (DM), root-P concentration and uptake, aboveground tissue-P uptake, total aboveground and total plant DM, grain yield, and grain P uptake from CPST and ECST did not differ from DAP or TSP. However, aboveground tissue-P concentration was greater (P &lt; 0.05) from TSP (0.05%) than from ECST, CPST, and the unamended control (UC). Total aboveground (i.e., vegetative plus grain) tissue-P uptake was largest (P &lt; 0.05) from TSP (4.8 g m− 2), which did not differ from DAP or CPST, and was at least 1.1 times greater than from ECST and the UC. Despite only a few differences from the UC, the many similar rice responses among struvite and other common fertilizer-P sources suggest that struvite, especially ECST, is a potential alternative fertilizer-P source that warrants further research into struvite’s role in food production.

AgNPs break the wall cell in Chlorella vulgaris by oxidative stress generation

Silver nanoparticles are used commercially due in part to its antibacterial power. However, due to their nanoscale size, these may not be retained by filters wastewater reaching the aquatic environment, which could affect microorganisms of initial food-chain as microalgae. The purpose of this study was to elucidate the cytotoxic effects of silver nanoparticles (3-7nm) in freshwater phytoplankton (Chlorella vulgaris) ex situ. Silver nanoparticles synthesis was performed according to silver nitrate chemical reduction, they were characterized by scanning electron microscope. C. vulgaris collected from Chapala Lake, Jalisco, México, was kept under laboratory conditions. C. vulgaris, grown in Bristol broth, were exposed to different concentrations of silver nanoparticles (0.01, 0.1 and 1mg L-1) for 24 hours. An important cytotoxic effect was determined in C. vulgaris exposed to silver nanoparticles, manifested by decrement in Chlorophyll-a contents, morphological changes, prominent perforations in cell walls, important decrement of lipid contents and oxidative stress generation, that corresponding to the nanoparticle concentration.

Biogenic silica dynamics in coastal wetland sediments: A key driver of silicon and carbon biogeochemical cycling

AbstractBiogenic silica (biogenic Si) is a bioactive component crucial for the biogeochemical cycling of Si in terrestrial and aquatic ecosystems. Its formation and dissolution dynamics are intricately linked to carbon (C) cycling. However, knowledge about the source, composition, and factors controlling the distribution of biogenic Si in coastal wetland sedimentary environments is still limited. To address this lack of knowledge, we introduced a suite of geometric models for biogenic Si biovolume calculation and investigated biogenic Si assemblages, along with biogenic Si and biogenic Si‐occluded C contents, in sediments from representative coastal wetlands along the west coast of Bohai Bay. Our analysis showed that sedimentary biogenic Si predominantly derived from phytoliths (78.1% ± 5.8%), diatoms (18.2% ± 4.8%), and sponge spicules (3.7% ± 2.9%). Notably, phytolith assemblages were primarily composed of forms derived from the Poaceae family. The biogenic Si‐occluded C content (0.035–1.870 g kg−1) within these wetland sediments was consistent across both sites, accounting for 0.97–5.71% of the total organic C pool. Structural equation modeling indicated that total organic C, pH, and amorphous aluminum oxides either directly or indirectly influenced the biogenic Si content in coastal wetlands sediments. These results demonstrate the critical role that biogenic Si plays in the Si biogeochemical cycle and provide valuable information that advances our understanding of the biogeochemical interactions between Si and C in coastal wetland ecosystems.

Ubiquitous genome streamlined Acidobacteriota in freshwater environments

Abstract Acidobacteriota are abundant in soil, peatlands and sediments, but their ecology in freshwater environments remains understudied. UBA12189, an Acidobacteriota genus, is an uncultivated, genome-streamlined lineage with small genome size found in aquatic environments, in which detailed genomic analyses are lacking. Here, we analyzed 66 MAGs of UBA12189 (including 1 complete genome) from freshwater lakes and rivers in Europe, North America and Asia. UBA12189 have small genome sizes (&amp;lt; 1.4Mbp), low GC content and a highly diverse pangenome. In freshwater lakes, this bacterial lineage is abundant from the surface waters (epilimnion) down to 300 meters depth (hypolimnion). UBA12189 appears to be free-living from CARD-FISH analysis. When compared to other genome-streamlined bacteria such as Nanopelagicales and Methylopumilus, genome reduction has caused UBA12189 to have a more limited metabolic repertoire in carbon, sulfur and nitrogen metabolisms, limited numbers of membrane transporters, as well as a higher degree of auxotrophy for various amino acids, vitamins and reduced sulfur. Despite having reduced genomes, UBA12189 encodes proteorhodopsin, complete biosynthesis pathways for heme and vitamin K2, cbb3-type cytochrome c oxidases and heme-requiring enzymes. These genes may give a selective advantage during the genome streamlining process. We propose the new genus Acidiparvus, with two new species named “A. lacustris” and “A. fluvialis”. Acidiparvus is the first described genome streamlined lineage under the phylum Acidobacteriota, which is a free-living, slow-growing scavenger in freshwater environments.