PLOS ONE: [sortOrder=DATE_NEWEST_FIRST, sort=Date, newest first, q=subject:"Aquatic environments"]PLOShttps://journals.plos.org/plosone/webmaster@plos.orgaccelerating the publication of peer-reviewed sciencehttps://journals.plos.org/plosone/search/feed/atom?sortOrder=DATE_NEWEST_FIRST&unformattedQuery=subject:%22Aquatic+environments%22&sort=Date,+newest+firstAll PLOS articles are Open Access.https://journals.plos.org/plosone/resource/img/favicon.icohttps://journals.plos.org/plosone/resource/img/favicon.ico2024-03-28T16:29:15ZCharacterization of geological and lithological features in the area proximal to tritium-contaminated groundwater at the Semipalatinsk test siteMedet AktayevSergey SubbotinAssan AidarkhanovAlmira AidarkhanovaLyubov TimonovaNatalya Larionova10.1371/journal.pone.03009712024-03-22T14:00:00Z2024-03-22T14:00:00Z<p>by Medet Aktayev, Sergey Subbotin, Assan Aidarkhanov, Almira Aidarkhanova, Lyubov Timonova, Natalya Larionova</p>
The article presents the results of a study of groundwater contaminated with tritium in the vicinity of the ‘Atomic Lake’ - a crater filled with water as a result of a thermonuclear explosion on the territory of the former Semipalatinsk test site. This crater was created as part of an experimental thermonuclear explosion in 1965 with the aim of creating an artificial reservoir in arid areas. The study was carried out to identify the source of groundwater contamination near the crater formed from a thermonuclear test. There were two possible factors of pollution: the influence of contaminated water from the crater on the groundwater of the adjacent area, or groundwater polluting the water in the crater. It was necessary to find out the source of groundwater contamination and its connection with the water in the funnel. For this purpose, a study of the geological and lithological conditions of the territory adjacent to the funnel was carried out, which was carried out using drilling operations and hydrological measurements. Drilling work made it possible to study the depth of distribution of groundwater, hydrological work made it possible to determine the conditions of distribution of groundwater, as well as to take samples of groundwater. The assessment of the degree of groundwater contamination was carried out through water sampling and laboratory analysis. As a result, it was established that the geological and lithological conditions of the area limit the flow of contaminated groundwater to the water in the crater - the ‘Atomic Lake’. Despite the fact that the waters in the crater from a thermonuclear explosion and the groundwater of the adjacent territory are contaminated with the radionuclide tritium, they have different sources of contamination and are not interconnected. Radionuclide analysis of groundwater showed that increased concentrations of tritium with a specific activity of up to 95 000 Bq/l are found in groundwater near the river bed. Shagan and this is due to the influence of the flow of groundwater coming from other parts of the landfill.Spatio-temporal patterns of whiting (<i>Merlangius merlangus</i>) in the Adriatic Sea under environmental forcingEmanuele AsciuttoFederico MaioliChiara ManfrediAlessandra AnibaldiJacopo CiminiIgor IsailovićBojan MarčetaMichele Casini10.1371/journal.pone.02899992024-03-22T14:00:00Z2024-03-22T14:00:00Z<p>by Emanuele Asciutto, Federico Maioli, Chiara Manfredi, Alessandra Anibaldi, Jacopo Cimini, Igor Isailović, Bojan Marčeta, Michele Casini</p>
Understanding how environmental factors affect species distribution is crucial for the conservation and management of marine organisms, especially in the face of global changes. Whiting (<i>Merlangius merlangus</i>) is a demersal cold-temperate fish, considered a ‘relict species’ in the Adriatic Sea. Despite its significance to commercial fisheries in the region, the specific drivers behind its spatial and temporal patterns have not been thoroughly examined. Here, we fitted a set of Generalized Linear Mixed Effects Models to data collected in the Northern and Central Adriatic from 1999 to 2019 during the Mediterranean International Trawl Survey to investigate the potential influence of depth, seafloor temperature and seafloor dissolved oxygen on the annual biomass density and spatial distribution of whiting in the spring-summer season. Our results showed that depth, and to a lesser degree temperature and oxygen, are important predictors of whiting distribution in this period, with preferences for depths of ~ 45 m, temperature of ~ 15.4°C and dissolved oxygen > 5.5 ml L<sup>-1</sup>. We predicted a persistent core area of distribution in front of the Po River Delta, in the Northern Adriatic Sea, while the density progressively declined towards the Central and Southern Adriatic Sea along the Italian coast. Additionally, the temporal trend exhibited high fluctuations over the years, occurring in cycles of 3 to 4 years. Finally, by comparing the biomass density estimates obtained under optimal conditions with those derived from the actual values for each variable, our analysis revealed that temperature had a pronounced and general impact on biomass density in the northern survey area (predictions revealed a density reduction of approximately two-thirds), while oxygen displayed a minor and more localized influence. This work deepens the current knowledge about the ecology of whiting in the Adriatic Sea and provides support for the conservation and management of this species.Study on the methodology of emergency decision-making for water transfer project contingencies: A case-based reasoning and regret theory approachFeng LiXuewan DuXin HuangXiaoxia Fei10.1371/journal.pone.03002722024-03-21T14:00:00Z2024-03-21T14:00:00Z<p>by Feng Li, Xuewan Du, Xin Huang, Xiaoxia Fei</p>
To tackle the global water imbalance problem, a multitude of inter-basin water transfer projects have been built worldwide in recent decades. Nevertheless, given the complexity and safety challenges associated with project operation, effective emergency decision-making is crucial for addressing unforeseen incidents. Hence, this research has developed a two-stage emergency decision-making framework to tackle the uncertainty in the development trends of emergencies in inter-basin water transfer projects. (1) The first stage mainly utilizes case-based reasoning techniques to extract historical case information and disposal plans for inter-basin water transfer projects. Subsequently, a holistic similarity model is built by employing structural similarity and local attribute similarity algorithms to identify highly similar historical cases. (2) The second stage involves the optimization and adjustment of decision-making plans based on the dynamic evolution characteristics of emergencies. It utilizes the theory of decision-makers regret psychology and combines it with practical case studies to verify the scientific rationality of the method. This enables it to achieve effective multidimensional expression and rapid matching of scenarios, satisfying the decision-making requirements of "scenario response". Finally, this study compares the results obtained from this method with those computed using the traditional TOPSIS method and fuzzy comprehensive evaluation method, further validating its feasibility and effectiveness. In practice, this method can provide effective support for decision-makers work.Natural disasters, livelihood, and healthcare challenges of the people of a riverine island in Bangladesh: A mixed-method explorationAhmed HossainAnika Tasneem ChowdhuryMasum MahbubMahmuda KhanTaifur RahmanAzaz Bin SharifHeba HijaziMohamad Alameddine10.1371/journal.pone.02988542024-03-21T14:00:00Z2024-03-21T14:00:00Z<p>by Ahmed Hossain, Anika Tasneem Chowdhury, Masum Mahbub, Mahmuda Khan, Taifur Rahman, Azaz Bin Sharif, Heba Hijazi, Mohamad Alameddine</p>
Background <p>Bangladesh’s islands, because of their geographical location, frequently encounter crises like floods and river erosion, which pose significant threats to the residents’ well-being and livelihoods. To delve into the effects of these disasters on livelihood and healthcare challenges, a mixed-method study was undertaken in a riverine-island near a major river of Bangladesh.</p> Methodology <p>Between February 15th and February 28th, 2023, a cross-sectional study was conducted on an island in Bangladesh. The quantitative method involved conducting a survey of 442 households, with a total of 2921 participants. Additionally, 10 in-depth interviews and 10 key-informant interviews were conducted using semi-structured guidelines. Qualitative interviews were audio-recorded, transcribed verbatim, and analyzed using a thematic analysis. Triangulation was employed in this study through the integration of qualitative and quantitative analysis, resulting in the presentation of findings that offer an in-depth comprehension of the phenomenon being investigated.</p> Results <p>River erosions and floods are common and recurring natural disasters that significantly impact the lives of the riverine island inhabitants. These disasters often disrupted their livelihoods, forced many residents to endure substandard living conditions or relocated during flood events. The island faced a low diagnostic prevalence of chronic diseases (e.g., 5.1% of adults were hypertension and 2.5% are diabetes) because of the absence of diagnostic facilities and a shortage of certified doctors. A significant number of chronic illness people in the community turned to alternative medicine sources (39.3%) such as homeopathy, Kabiraj, and Ayurvedic medicine, especially it gets increased during periods of natural disasters. Moreover, reproductive aged women revealed that 79.4% of them gave birth at home, with 6.0% of these home deliveries resulting in miscarriage or infant death. The destruction of crops, unstable job opportunities, an inadequate educational system, and a deficient healthcare delivery system exacerbated the hardships faced by the population affected by these disasters.</p> Conclusion <p>The failure to seek treatment for chronic diseases and undiagnosed diseases is a significant health issue among the aging adults on the island. Island residents face the challenge of establishing effective prevention strategies for the well-being of older adults especially at the period of natural disasters. It is crucial for the government and non-governmental organizations (NGOs) to collaborate to prevent the negative effects of floods and river erosions. This should include efforts to enhance the quality of education, healthcare services, job opportunities, and financial assistance for rebuilding homes.</p>Persistent long-term habitat use by Florida manatees at Fort Pierce, Florida from 1997 to 2020Rachel TennantBeth BradyKim LoveEric RamosRyan Schloesser10.1371/journal.pone.02976362024-03-21T14:00:00Z2024-03-21T14:00:00Z<p>by Rachel Tennant, Beth Brady, Kim Love, Eric Ramos, Ryan Schloesser</p>
To survive cold winters, Florida manatees (<i>Trichechus manatus latirostris</i>) depend on artificial (i.e., power plants) and natural warm water sources such as springs and passive thermal basins. Passive thermal basins can provide critical habitat for manatees for short or extended periods of time. The Henry D. King Powerplant in Fort Pierce, Florida discharged warm water into Moore’s Creek until it went offline in 1995. However, it is unknown to what degree manatees continue to occupy this area and how environmental factors influence their occurrence in the creek. To explore this, we examined the habitat use of Florida manatees in Moore’s Creek after the shutdown from November 1997 to March 2020 from daily counts of manatees. In addition, we correlated local environmental data (ambient air, temperature, salinity) to assess if Moore’s Creek had properties indicative of a passive thermal basin. Results indicated there was not an increase or decrease in habitat use over twenty years in the Creek. The consistent use of Moore’s Creek over the study period suggests that this habitat possesses thermal and freshwater resources to support manatee occurrence long-term. These findings provide robust support for the importance of this habitat and passive thermal basins for Florida manatees.Latitudinal variation in seagrass communities with special emphasis on post-tsunami status in the Andaman and Nicobar archipelago, IndiaSwapnali GoleNehru PrabakaranSumit PrajapatiSohini DudhatHimansu DasSivakumar KuppusamyJeyaraj Antony Johnson10.1371/journal.pone.03006542024-03-20T14:00:00Z2024-03-20T14:00:00Z<p>by Swapnali Gole, Nehru Prabakaran, Sumit Prajapati, Sohini Dudhat, Himansu Das, Sivakumar Kuppusamy, Jeyaraj Antony Johnson</p>
We studied spatial variation in seagrass communities in the Andaman and Nicobar archipelago (ANI), India using latitude as a surrogate variable. We classified the ANI into five latitudinally distinct island groups: North & Middle Andaman, Ritchie’s archipelago, South Andaman, Little Andaman, and the Nicobar archipelago. We evaluated the Importance Value Index (IVI) for species to determine the ecologically dominant seagrasses within each Island group. Later, we related our findings to investigate the three decadal pre- and post-tsunami status of seagrass habitats in the ANI which were severely impacted by the Indian Ocean tsunami of 2004. Six of the 11 observed species, such as <i>Halophila ovalis</i>, <i>Halophila beccarii</i>, <i>Halophila minor</i>, <i>Halodule pinifolia</i>, <i>Thalassia hemprichii</i>, and <i>Cymodocea rotundata</i>, dominated the seagrass population among all island groups. Seagrass composition significantly varied across the five investigated latitudinal gradients. Seagrass communities in ’Ritchie’s Archipelago and Nicobar’ and ’South Andaman and Little Andaman’ revealed the highest and lowest variation. Further, Ritchie’s Archipelago and Nicobar had the highest species richness (n = 10), followed by North & Middle Andaman (n = 8), and the lowest in South and Little Andaman (n = 6). Despite similar species richness and composition, Nicobar contributed to the highest seagrass coverage compared to the lowest recorded in the Ritchie’s Archipelago. Our observations on the re-colonization of disturbed areas by early successional and historical species suggest recovery of the seagrass population in the ANI post-disturbance. Lastly, co-variates associated with latitude as a surrogate warrant further investigation.CO<sub>2</sub> and CH<sub>4</sub> dynamics in a eutrophic tropical Andean reservoirEliana Bohórquez-BedoyaJuan Gabriel León-HernándezAndreas LorkeAndrés Gómez-Giraldo10.1371/journal.pone.02981692024-03-20T14:00:00Z2024-03-20T14:00:00Z<p>by Eliana Bohórquez-Bedoya, Juan Gabriel León-Hernández, Andreas Lorke, Andrés Gómez-Giraldo</p>
We studied the dynamics of methane (CH<sub>4</sub>) and carbon dioxide (CO<sub>2</sub>) in a eutrophic tropical reservoir located in the Colombian Andes. Temporal and spatial dynamics were addressed through sampling during six field campaigns conducted throughout a two-year period. We monitored fluxes at the air-water interface, dissolved gas concentrations, physical and chemical properties of the water column, microstructure profiles of turbulence, and meteorological conditions. Throughout the study period, the reservoir was a persistent source of CH<sub>4</sub> to the atmosphere with higher emissions occurring in the near inflow region. During periods of low water levels, both the emissions and surface concentrations of CH<sub>4</sub> were higher and more spatially heterogeneous. The measured CO<sub>2</sub> fluxes at the air-water interface changed direction depending on the time and location, showing alternating uptake and emissions by the water surface. Mass balances of dissolved CH<sub>4</sub> in the surface mixed layer revealed that biochemical reactions and gas evasion were the most significant processes influencing the dynamics of dissolved CH<sub>4</sub>, and provided new evidence of possible oxic methane production. Our results also suggest that surface CH<sub>4</sub> concentrations are higher under more eutrophic conditions, which varied both spatially and temporally.Obtaining accurate population estimates with reduced workload and lower fish mortality in multi-mesh gillnet sampling of a large pre-alpine lakeSteffen BaderJulia Gaye-SiesseggerBarbara ScholzMário Mota-FerreiraAlexander Brinker10.1371/journal.pone.02997742024-03-18T14:00:00Z2024-03-18T14:00:00Z<p>by Steffen Bader, Julia Gaye-Siessegger, Barbara Scholz, Mário Mota-Ferreira, Alexander Brinker</p>
The EU Water Framework Directive requires monitoring of the ecological status of lakes, with fish as a relevant class of biotic quality indicator, but monitoring fish populations in large lakes is demanding. This study evaluated use in Lake Constance of a novel multi-mesh gillnet modified to reduce catch numbers. In direct comparison with conventional European Committee for Standardization (CEN) nets we achieved 48% reduction in fish mortality with 38% less labour for tasks directly influenced by fish catch numbers, while maintaining comparable species composition and catch per unit effort. Comparison of mesh sizes indicated no significant reduction in species detection in area-reduced panels of the small mesh sizes, while total observed species richness was greater when using the modified nets. Differences in benthic species communities among depth strata were common, while those of pelagic zones were more homogeneous and did not differ significantly with depth. Catches of different net types from the same depth stratum did not exhibit significant differences. The dominance structure of the most common species, relevant to lake assessment, was similar in catches of both net types, suggesting overall superiority of the modified nets in Lake Constance. Sampling conducted according to standard European CEN protocol, while deploying 60% fewer nets, yielded sufficiently precise abundance estimates for monitoring shallow areas of the benthic zone. A 50% difference in the abundance of dominant species was detected among sampling events with a certainty of 95%. The sample did not provide comparable accuracy in deep benthic strata or the pelagic zone, but was adequate to record complete inventories of species present. Based on this trial data, a new stratified sampling design is proposed for monitoring large lake fish communities for ecological assessment. Depth-dependent fish communities were used to calculate the required number of nets, which resulted in a 69% reduction for the entire lake compared to the CEN calculation method. Using the modified nets increases the feasibility of performing WFD surveys, by reducing effort and cost, while the simultaneous halving of fish mortality minimises the negative impact of fish surveys.The impact of rivers and lakes on urban transportation expansion: A case study of the century-long evolution of the road network in Wuhan, ChinaRan PengKeyuan DingHaixu GuoXueliang LiuYehao LiuHuaiyang WengRui Li10.1371/journal.pone.02986782024-03-18T14:00:00Z2024-03-18T14:00:00Z<p>by Ran Peng, Keyuan Ding, Haixu Guo, Xueliang Liu, Yehao Liu, Huaiyang Weng, Rui Li</p>
Throughout history, rivers and lakes have wielded a profound influence on the dynamics of urban transportation expansion. To illustrate this phenomenon, we turn to the century-long evolution of the road network in Wuhan, China, as a case study. The study aims to explore the relationship framework between water bodies and urban transportation, characterized by the sequence of “strong connection” to “weakened connection”, then to “mutual restriction”, and ultimately to “mutual benefit”. Additionally, the analysis of the impact mechanisms of rivers and lakes on urban transportation at different stages of development is also a key research objective. To facilitate our exploration, we select the road networks in Wuhan from four years of 1922, 1969, 1995, and 2023 as the primary research subjects. By establishing water buffers, we scrutinize the evolving characteristics of riverside and lakeside transportation amidst the city’s expansion. Based on the modified shortest path model, we introduce the innovative concepts of “Detour Index” and “Weighted Detour Index” to assess the road accessibility of each node in the city based on its inherent environmental conditions. This allows for the effective analysis of the potential impact of water bodies as “obstacles” on the road network at different stages of urban development. The study found that in the areas adjacent to the rivers and lakes in Wuhan, there is insufficient road accessibility based on their inherent environmental conditions. Particularly, some areas along the rivers may become “terminals” in the urban road network. Furthermore, during the process of urban expansion, the correlation between the urban road network and rivers continues to weaken, while the correlation with lakes continues to strengthen. These conclusions can provide valuable insights for the planning of urban roads near water bodies.Digital image processing: A new tool for morphological measurements of freshwater turtles under rehabilitationAshish Kumar PandaVikas VermaAnupam SrivastavRuchi BadolaSyed Ainul Hussain10.1371/journal.pone.03002532024-03-14T14:00:00Z2024-03-14T14:00:00Z<p>by Ashish Kumar Panda, Vikas Verma, Anupam Srivastav, Ruchi Badola, Syed Ainul Hussain</p>
Freshwater fauna is facing an uphill task for survival in the Ganga Basin, India, due to a range of factors causing habitat degradation and fragmentation, necessitating conservation interventions. As part of the ongoing efforts to conserve the freshwater fauna of the Basin, we are working on rehabilitating rescued freshwater chelonians. We carry out various interventions to restore rescued individuals to an apparent state of fitness for their release in suitable natural habitats. Morphometric measurements are crucial to managing captive wild animals for assessing their growth and well-being. Measurements are made using manual methods like vernier caliper that are prone to observer error experience and require handling the specimens for extended periods. Digital imaging technology is rapidly progressing at a fast pace and with the advancement of technology. We acquired images of turtles using smartphones along with manual morphometric measurements using vernier calipers of the straight carapace length and straight carapace width. The images were subsequently processed using ImageJ, a freeware and compared with manual morphometric measurements. A significant decrease in the time spent in carrying out morphometric measurements was observed in our study. The difference in error in measurements was, however, not significant. A probable cause for this may have been the extensive experience of the personnel carrying out the measurements using vernier caliper. Digital image processing technology can cause a significant reduction in the stress of the animals exposed to handling during measurements, thereby improving their welfare. Additionally, this can be used in the field to carry out morphometric measurements of free-ranging individuals, where it is often difficult to capture individuals, and challenges are faced in obtaining permission to capture specimens.Field application of de novo transcriptomic analysis to evaluate the effects of sublethal freshwater salinization on <i>Gasterosteus aculeatus</i> in urban streamsCamilo Escobar-SierraKathrin P. Lampert10.1371/journal.pone.02982132024-03-13T14:00:00Z2024-03-13T14:00:00Z<p>by Camilo Escobar-Sierra, Kathrin P. Lampert</p>
Freshwater salinization poses global challenges for aquatic organisms inhabiting urban streams, impacting their physiology and ecology. However, current salinization research predominantly focuses on mortality endpoints in limited model species, overlooking the sublethal effects on a broader spectrum of organisms and the exploration of adaptive mechanisms and pathways under natural field conditions. To address these gaps, we conducted high-throughput sequencing transcriptomic analysis on the gill tissue of the euryhaline fish <i>Gasterosteus aculeatus</i>, investigating its molecular response to salinity stress in the highly urbanized river Boye, Germany. We found that in stream sections with sublethal concentrations of chloride costly osmoregulatory systems were activated, evidenced by the differential expression of genes related to osmoregulation. Our enrichment analysis revealed differentially expressed genes (DEGs) related to transmembrane transport and regulation of transport and other osmoregulation pathways, which aligns with the crucial role of these pathways in maintaining biological homeostasis. Notably, we identified candidate genes involved in increased osmoregulatory activity under salinity stress, including those responsible for moving ions across membranes: ion channels, ion pumps, and ion transporters. Particularly, genes from the solute carrier family SLC, aquaporin <i>AQP1</i>, chloride channel <i>CLC7</i>, ATP-binding cassette transporter <i>ABCE1</i>, and ATPases member ATAD2 exhibited prominent differential expression. These findings provide insights into the potential molecular mechanisms underlying the adaptive response of euryhaline fish to salinity stress and have implications for their conservation and management in the face of freshwater salinization.Point Pattern Analysis (PPA) as a tool for reproducible archaeological site distribution analyses and location processes in early iron age south-west GermanyGiacomo BilottiMichael KempfEljas OksanenLizzie ScholtusOliver Nakoinz10.1371/journal.pone.02979312024-03-13T14:00:00Z2024-03-13T14:00:00Z<p>by Giacomo Bilotti, Michael Kempf, Eljas Oksanen, Lizzie Scholtus, Oliver Nakoinz</p>
Point Pattern Analysis (PPA) has gained momentum in archaeological research, particularly in site distribution pattern recognition compared to supra-regional environmental variables. While PPA is now a statistically well-established method, most of the data necessary for the analyses are not freely accessible, complicating reproducibility and transparency. In this article, we present a fully reproducible methodical framework to PPA using an open access database of archaeological sites located in south-west Germany and open source explanatory covariates to understand site location processes and patterning. The workflow and research question are tailored to a regional case study, but the code underlying the analysis is provided as an R Markdown file and can be adjusted and manipulated to fit any archaeological database across the globe. The Early Iron Age north of the Alps and particularly in south-west Germany is marked by numerous social and cultural changes that reflect the use and inhabitation of the landscape. In this work we show that the use of quantitative methods in the study of site distribution processes is essential for a more complete understanding of archaeological and environmental dynamics. Furthermore, the use of a completely transparent and easily adaptable approach can fuel the understanding of large-scale site location preferences and catchment compositions in archaeological, geographical and ecological research.Community’s knowledge, perceptions and preventive practices on Onchocerciasis in Jimma zone, Ethiopia, formative mixed studyDaba AbdissaYohannes KebedeMorankar SudhakarGelila AbrahamGebeyehu BulchaTeshome ShiferawNimona BerhanuFiranbon TeshomeHirpa MiechaZewdie Birhanu10.1371/journal.pntd.00119952024-03-13T14:00:00Z2024-03-13T14:00:00Z<p>by Daba Abdissa, Yohannes Kebede, Morankar Sudhakar, Gelila Abraham, Gebeyehu Bulcha, Teshome Shiferaw, Nimona Berhanu, Firanbon Teshome, Hirpa Miecha, Zewdie Birhanu</p>
Background <p>In Ethiopia, Onchocerciasis is a prevalent neglected tropical disease, currently targeted for elimination with mass drug administration and community behavioral changes towards sustained control and eventual elimination. This study aimed to elucidate the awareness, perceptions and practices of endemic communities in Jimma Zone, Ethiopia.</p> Methods and materials <p>Community-based cross-sectional study triangulated with qualitative method was conducted from October-November, 2021. A multistage sampling was employed and data were collected using a pre-tested interviewer-administered structured questionnaire. Logistic regression was used to identify the predictors of comprehensive knowledge and preventive practice. Adjusted odds ratios were calculated at 95% confidence interval (CI) and considered significant with a p-value of <0.05. Kruskal-Whallis and Mann-whitney tests were used to compare median risk perception score by socio-demographic factors. Qualitative data were collected through focus group discussions and key informant interviews and transcribed verbatim. Then the data were coded, categorized, and themes were developed.</p> Result <p>The overall prevalence of adequate comprehensive knowledge was 48.8% (95% CI: 44.9, 52.3), high risk perception was 18.7% (95%CI15.9, 21.4) and preventive practice was 46.9%(95%CI:(43.3,50.4). High risk perception[AOR = 1.95 95%CI: (1.32, 2.89] was statistically significant with comprehensive knowledge, likewise knowledge of mode of transmission [AOR = 2.64 95% CI: (1.44, 4.85)], knowledge of consequences [AOR = 2.12 95%CI: (1.21, 3.72)] and knowledge of preventive measures [AOR = 15.65,95%CI:(10.1, 24.2)] were statistically significant with preventive practice. The median risk perception was varied significantly between the groups by educational status, study district and age category. Qualitative evidence showed that there were great community knowledge gap about the disease.</p> Conclusion <p>Community knowledge, perceptions, and practices are unacceptably low. Risk perception was significantly associated with comprehensive knowledge, likewise knowledge of mode of transmission, consequences and preventive measures were significantly associated with preventive practice. This implies knowledge is a key component of effective prevention strategies as it is a necessary condition for the behavior change.</p>Constructed wetland as a green remediation technology for the treatment of wastewater from underground coal gasification processŁukasz JałowieckiAleksandra Strugała-WilczekKatarzyna PonikiewskaJacek BorgulatGrażyna PłazaKrzysztof Stańczyk10.1371/journal.pone.03004852024-03-12T14:00:00Z2024-03-12T14:00:00Z<p>by Łukasz Jałowiecki, Aleksandra Strugała-Wilczek, Katarzyna Ponikiewska, Jacek Borgulat, Grażyna Płaza, Krzysztof Stańczyk</p>
The wastewater from underground coal gasification (UCG) process has extremely complex composition and high concentrations of toxic and refractory compounds including phenolics, aliphatic and aromatic hydrocarbons, ammonia, cyanides, hazardous metals and metalloids. So, the development of biological processes for treating UCG wastewater poses a serious challenge in the sustainable coal industry. The aim of the study was to develop an innovative and efficient wetland construction technology suitable for a treatment of UCG wastewater using available and low-cost media. During the bioremediation process the toxicity of the raw wastewater decreased significantly between 74%—99%. The toxicity units (TU) ranged from values corresponding to very high acute toxic for raw wastewater to non-toxic for effluents from wetland columns after 60 days of the experiment. The toxicity results correlated with the decrease of some organic and inorganic compounds such as phenols, aromatic hydrocarbons, cyanides, metals and ammonia observed during the bioremediation process. The removal percentage of organic compounds like BTEX, PAHs and phenol was around 99% just after 14 days of treatment. A similar removal rate was indicated for cyanide and metals (Zn, Cr, Cd and Pb). Concluded, in order to effectively assess remediation technologies, it is desirable to consider combination of physicochemical parameters with ecotoxicity measurements. The present findings show that wetland remediation technology can be used to clean-up the heavily contaminated waters from the UCG process. Wetland technology as a nature-based solution has the potential to turn coal gasification wastewater into usable recycled water. It is economically and environmentally alternative treatment method.Rainfall as a driver for near-surface turbulence and air-water gas exchange in freshwater aquatic systemsEliana Bohórquez-BedoyaLorenzo RovelliAndreas Lorke10.1371/journal.pone.02999982024-03-12T14:00:00Z2024-03-12T14:00:00Z<p>by Eliana Bohórquez-Bedoya, Lorenzo Rovelli, Andreas Lorke</p>
Gas fluxes from aquatic ecosystems are a significant component of the carbon cycle. Gas exchange across the air-water interface is regulated by near-surface turbulence and can be controlled by different atmospheric forcing conditions, with wind speed and surface buoyancy flux being the most recognized drivers in empirical studies and modeling approaches. The effect of rainfall on near-surface turbulence has rarely been studied and a consistent relationship between rain rate and near-surface turbulence has not yet been established. In this study, we addressed some limitations still present in the quantitative understanding of the effect of rain rate on near-surface turbulence and on the resulting gas transfer velocity in freshwater. We performed controlled laboratory experiments over a wide range of rain rates (7 to 90 mm h<sup>-1</sup>) and estimated gas transfer velocities from high-resolution measurements of O<sub>2</sub> concentration, while rain-induced turbulence was characterized based on particle image velocimetry. We found that the rain-induced dissipation rates of turbulent kinetic energy declined with depth following a consistent power-law relationship. Both energy dissipation rates and gas transfer velocity increased systematically with the rain rate. The results confirm a causal relationship between rainfall, turbulence, and gas exchange. We propose a power-law relationship between near-surface turbulent dissipation rates and rain rate. In combination with surface renewal theory, we derived a direct relationship between gas transfer velocity and rain rate, which can be used to assess the importance of short-term drivers, such as rain events, on gas dynamics and biogeochemical cycling in aquatic ecosystems.