Water Sites Research Articles

Environmental Drivers of an Intertidal Bryozoan Community in the Barents Sea: A Case Study

Simple SummaryBryozoans are colonial organisms that are usually found attached to solid substrata. They are known to be common components of benthic communities from the littoral zone to deep-sea areas. Despite the long history of bryozoan research in the Barents Sea, intertidal communities of this group are less studied than those at open water sites. This is particularly true for the assessment of the role of environmental factors in diversity and biomass fluctuations of Arctic bryozoan assemblages. We collected bryozoans at two adjoining coastal sites in the southern Barents Sea and detected range extension of one boreal species, which reflects a warming trend and borealization of the benthic fauna in the region. In general, the total bryozoan biomass and diversity were lower than in deep-water sites of the sea. Salinity and temperature were found to be the main predictors of bryozoan species richness and biomass, respectively, with more diverse and abundant assemblages occupying habitats with higher salinity and lower temperature. Our findings are in accordance with a general opinion that benthic communities of the coastal Barents Sea are mainly controlled by temperature regime fluctuations and freshwater runoffs.There is a lack of knowledge regarding the modern status of intertidal bryozoan communities in the coastal Barents Sea. Here, we studied species composition, richness, and biomass of bryozoans in Yarnyshnaya and Dalnezelenetskaya Bays, both located in the eastern part of the Kola Peninsula (Barents Sea), in summer. Species composition and biodiversity were consistent with previous research but the record of the ctenostome bryozoan Walkeria uva is the first for the region indicating eastward range expansion of this species associated with climate forcing in the Arctic. Mean biomass was relatively low accounting for 2.25 ± 0.95 g·m−2. The most common species were Eucratea loricata, Harmeria scutulata, Crisia eburnea, and Cribrilina cryptooecium averaging 96% of the total biomass. Cluster analysis delineated two distinct groups of stations, one with true marine conditions and another with brackish water conditions. Redundancy analysis revealed that bryozoan diversity was strongly associated with salinity fluctuations being extremely low at brackish water sites. In contrast, water temperature was found to be a significant contributor to biomass with the lowest values found at warmer waters probably owing to the predominance of Boreo-Arctic species which prefer lower-temperatures. Other hydrological variables (dissolved organic matter, silicates, and oxygen) were consistent with usual summer values and had no significant effects on the bryozoan assemblages. Our study provides a reference point for further biodiversity studies in changing marine ecosystems of the Arctic region.

The variable presence of Leptospira in the environment; an epidemiological explanation based on serial analysis of water samples.

Human leptospirosis involves the classic epidemiological triad (agent, host and environment); hence the investigations should include the knowledge on Leptospira within the animals and the environment. The objectives of this study are to explore the abundance of Leptospira in different climate zones of Sri Lanka and to describe the presence of Leptospira in the same water source at serial time points. First, water and soil samples were collected from different parts of Sri Lanka (Component-1); second, water sampling continued only in the dry zone (Component-2). Finally, serial water sampling from ten open wells was performed at five different time points (Component-3). Quantitative PCR of water and metagenomic sequencing of soil were performed to detect Leptospira. Three replicates for each sample were used for PCR testing, and positive result of two or more replicates was defined as 'strongly positive,' and one positive replicate was defined as positive. In the water and soil sample analysis in the whole country (Component-1), two out of 12 water sites were positive, and both were situated in the wet zone. Very small quantities of the genus Leptospira were detected by 16 amplicon analysis of soil in all 11 sites. In the dry zone water sample analysis (Component-2), only samples from 6 out of 26 sites were positive, of which one site was strongly positive. In the serial sample analysis (Component-3), Six, five, four, five, and six wells were positive in serial measurements. All wells were positive for at least one time point, while only one well was positive for all five time points. Proximity to the tank and greater distances from the main road were associated with strong positive results for Leptospira (P<0.05). The presence of Leptospira was not consistent, indicating the variable abundance of Leptospira in the natural environment. This intermittent nature of positivity could be explained by the repetitive contamination by animal urine.

Enhancing Sampling of Water Rehydration on Ligand Binding: A Comparison of Techniques.

Water often plays a key role in protein structure, molecular recognition, and mediating protein-ligand interactions. Thus, free energy calculations must adequately sample water motions, which often proves challenging in typical MD simulation time scales. Thus, the accuracy of methods relying on MD simulations ends up limited by slow water sampling. Particularly, as a ligand is removed or modified, bulk water may not have time to fill or rearrange in the binding site. In this work, we focus on several molecular dynamics (MD) simulation-based methods attempting to help rehydrate buried water sites: BLUES, using nonequilibrium candidate Monte Carlo (NCMC); grand, using grand canonical Monte Carlo (GCMC); and normal MD. We assess the accuracy and efficiency of these methods in rehydrating target water sites. We selected a range of systems with varying numbers of waters in the binding site, as well as those where water occupancy is coupled to the identity or binding mode of the ligand. We analyzed the rehydration of buried water sites in binding pockets using both clustering of trajectories and direct analysis of electron density maps. Our results suggest both BLUES and grand enhance water sampling relative to normal MD and grand is more robust than BLUES, but also that water sampling remains a major challenge for all of the methods tested. The lessons we learned for these methods and systems are discussed.

The political ecology of water memory: Contending narratives of past hydraulic infrastructures in Barcelona (2015–2021)

In the context of ecological emergency and crisis of representation of the capitalist democracy, the battles over water management have become ever more politicised: who is to administer water resources, how, and with what legitimacy? This article examines a disregarded dimension of the recent water conflict in Barcelona by looking into the politics of memory as part of a struggle for legitimacy between the private water company Agbar, and Barcelona en Comú (BeC), the political platform governing the city since 2015, and defending the ‘remunicipalisation’ of water. By combining memory studies and critical discourse analysis we pay attention to the dynamic resignification of the hydraulic infrastructure as spaces or “sites of memory” (lieux de mémoire; Nora, 1998). Barcelona en Comú narrative retrieves a forgotten past of local sites and experiences in public management of water. In contrast, Agbar defends its legitimacy by advancing a narrative of linear progress and social inclusion that re-signifies its 150-year long history and co-opts key “empty signifiers” (Laclau, 2005) from the discourse of the Indignados and BeC. Theoretically, we advance that a temporal turn in political ecology and geography, complementing the concern with spatiality, could usefully draw on memory studies to analyse the growing memorialization of water discourses and sites, as well as their political significance. The article thus investigates a question that has not been systematically explored by political ecologists: how the entanglement of space and historical memory is mobilized in the conflict over the use and management of the environment.

Recognition of Significant Multi-Element Geochemical Signatures of Lower Soil on Hainan Island, China: Implications for Thermal Mineral Water Exploration

As an important geothermal resource, thermal mineral water has high resource efficiency and thermal energy efficiency. The aim of this study was to delineate prospective areas of thermal mineral water based on potential thermal mineral water sites and faults. Linear regression was used to process the temperature of 22 known thermal mineral water sites as dependent variables, and 54 indices of the lower soil of multipurpose regional geochemical surveys as independent variables, in the area of intermediate-acid intrusive rocks and sediment degeneration rocks on Hainan Island. Published data were quoted from the National Multi-Purpose Regional Geochemical Survey (Hainan Province, China). According to the regressive modelling of 2197 lower soil samples, 547 potential thermal mineral water sites were delineated after considering 4 factors—geological background, regional structure, interval of dependent variable’s predictive temperature, and boundary of independent variable’s contents—which were compared against 22 known thermal mineral water sites to choose the 2197 lower soil samples, based on the choice of prospective sites of thermal mineral water on Hainan Island. The results showed that the proportion of A1-level sites that were &gt;70 °C constituted 11% of all A1-level prospective sites, reflecting the superiority of east–west or north–east directional regional faults in controlling the distribution of thermal mineral water. This study shows the indications of the multipurpose regional geochemical survey with regards to thermal mineral water, which is one of the most important tourist resources of Hainan Island.

Characteristics and adsorption of Cr(VI) of biochar pyrolyzed from landfill leachate sludge

Landfill leachate sludge (LLS), originated from the infiltration of rainwater through dumping sites of waste and water contained in landfills, is a specific type of sewage. Since its large amount, environmental unfriendliness and compositional instability, the sustainable management and disposal of LLS requires urgent attention. In this study, LLS disposal problem was addressed along with the removal of chromium (Cr) from water. Firstly, the thermal behaviors of LLS were investigated through TG analysis. Secondly, LLS-based biochar (SC) was prepared in a tubular furnace, and the effect of pyrolysis temperature on the yield and properties of SC was investigated. Finally, using SC900 as Cr(VI) adsorbent, the influence of various factors on Cr(VI) adsorption were investigated. BET, FTIR, and XPS analyses were performed to determine the characteristics of SC and the variation of SC before and after adsorption. Results showed that, TG curve of LLS exhibited a rapid mass loss of 54.15% between 220 and 525 °C due to the cleavage of C-O and C-C bonds with the release of large amounts of CO2. The SC yields were in the range of 10.81–22.16% when the pyrolysis temperature ranged from 400° to 900°C. The optimal pyrolysis temperature for the preparation of the SCs was determined to be 900 °C, and SC900 had a relatively high BET surface area of 83.87 m2/g. exhibited the highest Cr(VI) adsorption of 17.46 mg/g. The main oxygen-containing functional groups (-OH, C-O, CO) present in the SC played an important role to adsorbed Cr(VI) and reduced it to Cr(III) at a low pH. As a result, 76.5–85.3% of the adsorbed Cr(VI) was reduced to the less toxic Cr(III). Moreover, only 0.52% (1.56 ppm) of the adsorbed Cr (from a 300 ppm solution) leached from SC900, which indicated the high stability of the adsorbed Cr in the SC.

Identifying the source and transformation of riverine nitrates in a karst watershed, North China: Comprehensive use of major ions, multiple isotopes and a Bayesian model

Nitrate (NO3−) contamination of surface water is a globally concern, especially in karstic regions affected by intensive agricultural activities. This study combines hydrochemistry, and environmental isotopes (δ2HH2O, δ18OH2O, δ15NNO3, and δ18ONO3) with a Bayesian isotope mixing model (Simmr) to reduce the uncertainty in estimating the contributions of different pollution sources. Samples were collected from 32 surface water sites in the Yufu River (YFR) watershed, North China, in September and December 2019. The results revealed that NO3−-N was the predominant form of inorganic nitrogen that caused the deterioration of water quality in the watershed, accounting for approximately 58% of the total nitrogen (TN). The hydrochemical compositions and nitrate isotopes indicated that NO3− mainly originated from soil nitrogen (SN), ammonium fertilizer (AF), but nitrate fertilizer (NF), manure and sewage (M&S) and atmospheric precipitation (AP) were limited. The isotopic composition of nitrate in the upper reaches of the watershed was mainly affected by microbial nitrification, while the mixture of multiple sources was the dominant nitrogen transformation process in the mid-lower reaches of the watershed. Simmr model outputs revealed that SN (56.5%) and AF (29.5%) were the primary contributor to riverine NO3− pollution, followed by NF (7.1%), MS (3.6%), and AP (3.4%) sources. Moreover, an uncertainty index (UI90) of the isotope mixing showed that SN (0.73) and AF (0.67) had the highest values, followed by NF (0.22), M&S (0.22) and AP (0.10). Chemical fertilizer and SN collectively contributed >50% of nitrate during the two sampling campaigns. These results indicated that reducing the application of nitrogen fertilizers and rational irrigation are the keys to alleviate of NO3− pollution. The study is helpful in understanding the source and transformation of riverine NO3− and effectively reducing NO3− pollution in karst agricultural rivers or watersheds.

Variation in water contact behaviour and risk of Schistosoma mansoni (re)infection among Ugandan school-aged children in an area with persistent high endemicity

BackgroundAnnual mass drug administration with praziquantel has reduced schistosomiasis transmission in some highly endemic areas, but areas with persistent high endemicity have been identified across sub-Saharan Africa, including Uganda. In these areas many children are rapidly reinfected post treatment, while some children remain uninfected or have low-intensity infections. The aim of this mixed-methods study was to better understand variation in water contact locations, behaviours and infection risk in school-aged children within an area with persistent high endemicity to inform additional control efforts.MethodsData were collected in Bugoto, Mayuge District, Uganda. Two risk groups were identified from a longitudinal cohort, and eight children with no/low-intensity infections and eight children with reinfections were recruited. Individual structured day-long observations with a focus on water contact were conducted over two periods in 2018. In all identified water contact sites, four snail surveys were conducted quarterly over 1 year. All observed Biomphalaria snails were collected, counted and monitored in the laboratory for Schistosoma mansoni cercarial shedding for 3 weeks.ResultsChildren came into contact with water for a range of purposes, either directly at the water sources or by coming into contact with water collected previously. Although some water contact practices were similar between the risk groups, only children with reinfection were observed fetching water for commercial purposes and swimming in water sources; this latter group of children also came into contact with water at a larger variety and number of sites compared to children with no/low-intensity infection. Households with children with no/low-intensity infections collected rainwater more often. Water contact was observed at 10 sites throughout the study, and a total of 9457 Biomphalaria snails were collected from these sites over four sampling periods. Four lake sites had a significantly higher Biomphalaria choanomphala abundance, and reinfected children came into contact with water at these sites more often than children with no/low-intensity infections. While only six snails shed cercariae, four were from sites only contacted by reinfected children.ConclusionsChildren with reinfection have more high-risk water contact behaviours and accessed water sites with higher B. choanomphala abundance, demonstrating that specific water contact behaviours interact with environmental features to explain variation in risk within areas with persistent high endemicity. Targeted behaviour change, vector control and safe water supplies could reduce reinfection in school-aged children in these settings.Graphical

Linkages between Forestry Best Management Practices and erosion in the southeastern U.S.

Numerous studies have concluded that forestry Best Management Practices (BMPs) are effective at mitigating erosion and sedimentation caused by forest operations; however, the complex relationship between forestry BMPs and erosion is largely unexamined. In this study, BMP implementation rates, which are percentages ranging from 0 to 100% that indicates how well an operator instituted recommended practices in the field, and predicted erosion rates, obtained by using USLE-Forest, were calculated for 108 recent harvests in twelve states and three physiographic regions in the southeastern U.S. BMP implementation rates were subdivided into three levels of application: BMP+ (>90% implementation), BMP-standard (80–90% implementation), and BMP− (<80% implementation). Skid trails (86.5 Mg ha−1 yr−1) and haul roads (90.3 Mg ha−1 yr−1) eroded at relatively high rates at the BMP− level across the southeast. This emphasizes the importance of adequate BMP measures such as utilizing water diversion structures and cover management at these features to better protect water quality. The overall weighted average erosion estimates for all regions at the BMP-standard (10.4 Mg ha−1 yr−1) and BMP+ (6.6 Mg ha−1 yr−1) levels were <11 Mg ha−1 yr−1, indicating that water quality and site productivity are largely protected when adequate BMPs are implemented, and Streamside Management Zones (SMZs) are utilized along streams. Approximately 94% of the sites sampled were classified as either BMP-standard or BMP+, demonstrating that BMPs are being implemented consistently throughout the southeast. Spearman ρ correlation analyses were performed for all variables. Forestry BMP implementation and erosion estimates had significant negative correlations, especially for skid trails (Spearman ρ = −0.59, p-value < 0.0001) and haul roads (Spearman ρ = −0.39, p-value = < 0.0001), as well as for all regions across the southeast. These variables, however, were poorly correlated for stream crossings, indicating that current audit questions in the southeast may not fully address erosion. Additionally, BMP implementation and erosion estimates exhibited a significant negative correlation (R2 = 0.28, p-value < 0.0001) based on a quadratic regression line for all features, reinforcing that as BMP implementation increases, predicted erosion generally decreases.

The use of demographic data to monitor population trends of the Nubian Ibex, Capra nubiana in Jordan (Mammalia: Bovidae)

The population status of the IUCN vulnerable Nubian Ibex Capra nubiana is largely unknown in the Middle East because of difficulties conducting intensive surveys. We tested the utility of camera-trapping at permanent water sites to estimate demographics and population trend of the species in the Dana Biosphere Reserve, Jordan. We also studied the relationship between precipitation and the Normalized Difference Vegetation Index NDVI on water site use by the Nubian Ibex, demographics, and population trend. The Nubian Ibex showed a mean annual productivity of 0.81 neonate/female and an adult female survival of 0.87 which is a lower survival rate than found in other ibex species. The mean potential annual rate of increase of this population (λ=1.14) was similar to those reported from other ibex species and indicated a viable population. The capture rate of camera traps (number of photographed animals/camera day) was found not to be a reliable index to monitor population trends because water site use was related to environmental conditions that could not be standardized or predicted a priori. Quantifying population demographic ratios using camera trapping allowed for monitoring the status of key population parameters and growth potential of Nubian Ibex populations in the Dana Reserve, and likely can be used to monitor population status and facilitate informed management of similar populations in the Middle East.

江西柘林水库鱼类群落结构及功能多样性分析

PDF HTML阅读 XML下载 导出引用 引用提醒 江西柘林水库鱼类群落结构及功能多样性分析 DOI: 10.5846/stxb202106031466 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目（2019YFD0900603）；财政部和农业农村部：国家现代农业产业技术体系资助（CARS-46）；中国水产科学研究院基本科研业务费院级湖库增殖渔业创新团队项目（2020TD57） Community structure and functional diversity of fishes in Zhelin Reservoir, Jiangxi Province Author: Affiliation: Fund Project: National Key Research and Development Program of China (No.No.2019YFD0900603); Supported by China Agriculture Research System of MOF and MARA（CARS-46）; Central Public-interest Scientific Institution Basal Research Fund，CAFS (NO.2020TD57) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为了解江西柘林水库鱼类群落结构和多样性的时空变化特征，研究鱼类物种多样性和功能多样性的关系，于2020年9月至2021年4月在该水库调查分析了鱼类物种组成、优势度及群落物种多样性和功能多样性。结果表明，共采集鱼类53种，分属于5目12科36属。其中，鲤形目（38种）种类最多，占调查物种数的71.69%，柘林水库上、中、下游库区分别采集到鱼类36、40和32种，各库区均以鲤形目鱼类为主，分别占采集物种数的72.97%、85.00%和75.00%。优势物种主要是䱗（Hemiculter leucisculus）、鳙（Aristichthys nobilis）和黄尾鲴（Xenocypris davidi），重要种主要是草鱼（Ctenopharyngodon idella）、鲢（Hypophthalmichthys molitrix）、鳊（Parabramis pekinensis）、鲫（Carassius auratus）、蒙古红鲌（Erythroculter mongolicus）等。鱼类群落结构季节性差异大于空间格局差异，主要表现为秋季和冬季之间；生物多样性指数Margalef和功能丰富度指数在上游修河水域相对较高，鱼类物种多样性和功能多样性空间格局差异性大于时间尺度下的差异性。物种多样性与功能多样性的回归分析结果显示，功能丰富度与物种多样性指数之间存在显著的正相关关系；功能冗余度与各物种多样性之间呈现负相关关系，说明物种数的增加导致了库区鱼类功能丰富度的增加和功能冗余度的降低，而功能均匀度未发生明显的变化，主要原因为调查区域内拥有不同功能性状的鱼类群体之间在个体数比例上呈现不均匀分布的模式，这一结果预示着拥有较多物种的群落生态位重叠度相对较低，生态系统受干扰后的恢复能力较差。总体而言，保护鱼类生物多样性和维护生态系统的稳定性应该通过调控鱼类种群结构达到提高鱼类群落冗余度以及资源和生境可用性的目的。 Abstract:To understand the spatial and temporal variation of fish assemblage structure and biodiversity, as well the relationships between fish taxonomical diversity and functional diversity, species compositions, the dominant species, taxonomical and functional diversity of fish communities which were captured from Zhelin Reservoir from September 2020 to April 2021 were investigated and analyzed. The results showed that a total of 53 fish species belonging to 5 orders, 12 families, and 36 genera were sampled with dominant Cyprinidae accounting for 71.69% of the total species. Among the reservoir spatial scales, 36, 40 and 32 fish species which accounting for 72.97%, 85.00% and 75.00% of the total sampled species were captured from upper-, middle- and low-reach, respectively. Hemiculter leucisculus, Aristichthys Nobilis and Xenocypris davidi were dominant species, while Ctenopharyngodon idella, Hypophthalmichthys molitrix, Parabramis pekinensis, Carassius auratus and Erythroculter mongolicus were main species in Zhelin Reservoir. The analysis of PERMANOVA (Permutational Multivariate Analysis of Variance) using the fish assemblage matrixes showed that the seasonal variation of species compositions was more significant than the spatial scale, and the variations were mainly performed between two seasons of antum and summer. Meanwhile, biodiversity indexes and functional diversity indexes of fish assembalges performed relative higher variations among spatial scales than temporal scales. Margalef index were relatively higher in the Xiuhe River than those in other water sites, while the indexes of Shannon, Simpson and Peilou indexes showed no variation among the reaches. Functional richness possessed relative higher level in upper reach than midlle and lower reaches, while functional evenness and functional disperse performed non changes among spatial scales. Functional redundancy had no variation among spatial and temporal scales. Regression analyses showed significant positive relationships between the biodiversity index of functional richenss and functional disperse with each taxonomical diversity index, while there were negative relationships between functional redundancy and taxonomical diversity indexes, which implying the increase of species richness led to the increase of the functional richness and decrease of functional redundancy. However, functional evenness did not change obviously which can mainly be explained by the disproportionate individuals of different fish functional groups. The results implied that interference resulted in a lower niche overlap of fish community with high species richness and lower ecosystem recovery ability. In general, the species diversity level of Zhelin Reservoir is lower and the anti-interference ability of this ecosystem is relatively weaker. To protect fish biodiversity and maintain the stability of the ecosystem, it is necessary to improve the fish community redundancy and the availability of resources and habitats by regulating the fish population structure. 参考文献 相似文献 引证文献

Sustainable control of malaria employing Gambusia fishes as biological control in Jalore and Barmer districts of Western Rajasthan

Sardar Sarovar Irrigation Canal system was constructed by Narmada Valley Development Authority (NVDA) to cater to drinking water as well as for irrigation purposes in Jalore and Barmer districts of Western Rajasthan. To cater to the needs of water for the villagers in the command areas, 'Diggies' (surface water tanks) with 'Sumpwells' (water supply surface tanks) were installed. In a health impact assessment study of the irrigation canals from December 2010 to February 2016, the breeding of two major malaria vectors. An. culicifacies and An. stephensi were observed in diggies and sumpwells. As a biological control, Gambusia affanis fishes were employed for larval control in such stagnated water sites during the intervention phase viz. February 2012 in 251 diggies and 251 sumpwells. A significant reduction of breeding in diggies (99.54%) and sumpwells (97.81%) was observed. The positivity and larval density (dip index) were monitored in the control from up to February 2016 for their sustainability.

Development of jacket substructure systems supporting 3MW offshore wind turbine for deep water sites in South Korea

This study aims to develop jacket substructures supporting a 3MW Offshore Wind Turbine (OWT) in water depth ranges of 25–40 m. A simplified structural design process is introduced and influences of jacket topological forms and brace systems on their dynamic performances are assessed. The results conclude that the topological configuration of the jacket substructure has a significant influence on the dynamic characteristics of the whole system, indicating a high priority when designing a jacket substructure for OWTs. Furthermore, two jacket substructures having the lowest material costs and the best performances under the Korean ocean environmental conditions are suggested. Additionally investigated in this study is a sensitivity of environmental loading directions on the structural performances of the jacket substructures. All the findings in this study might be very useful to assist the structural engineers when they design the support structures for large-scaled OWTs in the near future in South Korea.

SPATIOTEMPORALDYNAMICITY OF ENVIRONMENTAL VARIABLES AND WATER QUALITY INDEX IN AQUIFERS AND GROUNDWATER OF BLUE CITY USING MULTIVARIATE STATISTICAL TECHNIQUE

Thecurrent research investigates the quality of ten different surface water sites in and around Jodhpur using water quality ratings. This paper gives insight into water pollution's qualitative and quantitative extent. The water quality index (WQI)is usedfor assessing and comparing water quality. In each study region, a five-point grading scale was adopted to classify water quality as a single understandable value. Twelveparameters were employed for determining the WQI of different sites: turbidity, TSS, TDS, conductivity, alkalinity, hardness, calcium, magnesium, chloride, fluoride, and nitrate. Multivariate analysis of the samplesrevealed that most of the individual parameters are not in harmony with the standard values prescribed by the regulating authorities. According to the study, seasonal fluctuations play a significant effect in the hydrochemistry of surface water, indicating a change in WQI. Thesamples showed less pollution in the pre-monsoonseason as compared to post-monsoon. Overall, this paper lays forth a strategy for proper utilization and protection, as well as assesses the quality of surface water to determine its suitability for various uses and its impact on groundwater quality.

Annual, seasonal, and diel patterns in blue whale call occurrence off eastern Canada

Little is known about the year-round occurrence of blue whales in Atlantic Canadian waters. We used passive acoustic monitoring to investigate blue whale call presence and increase our understanding of year-round blue whale occurrence along the eastern edge of the Scotian Shelf, Nova Scotia, Canada. Blue whale calls were recorded at 3 deep water sites within and near the Gully Marine Protected Area from October 2012 to September 2014 using bottom-mounted passive acoustic recorders. Calls were categorized as either tonal or downsweeping. At all 3 sites, tonal calls occurred most often from November through January in both years and in August 2014, while the majority of downsweeping calls occurred during May through September 2014. There was no discernible diel pattern in the occurrence of tonal calls. Downsweeping calls occurred most often during evening twilight, with a dramatic peak in occurrence during the hour of 19:00 Atlantic Standard Time at all 3 sites. The peak in downsweeping call occurrence during evening twilight may have been related to blue whale foraging ecology. This study sheds light on the poorly understood year-round occurrence of blue whales off Atlantic Canada. Understanding when and where blue whales occur will help to inform management decisions for the protection and conservation of this endangered population.

Influence of catastrophic flood on microplastics organization in surface water of the Three Gorges Reservoir, China

The Three Gorges Dam (TGD) is the world's largest hydropower project. It could potentially influence the footprint and transport of microplastics (MPs) in Yangtze River, which is the largest riverine input of oceanic MPs worldwide. In addition to analyzing the MP particles of all size categories and polymer groups, we also evaluated the stability, pollution risk and source identification of MPs after the catastrophic flood of 2020 in the Three Gorges Reservoir (TGR) and downstream of the TGD. We found that the MP abundance (6214 ± 5394 particles/m3) in the TGR water increased by a 57.9% growth after this catastrophic flood. Interestingly, we observed the small-sized MPs (SMPs; < 300 μm) were dominant in the TGR (accounting for ∼65.4% of the total MP particles). After flooding, the main morphological types were fragment and fiber, while the major polymer was polyethylene (PE). Although the MP level was at a low pollution risk, 13.6% of the sampling sites in the TGR water faced potential ecological risks driven by SMPs. In particular, there was no significant difference in the abundances, morphological types, and polymer composition of MPs between upstream and downstream of the TGD (p > 0.05), indicating flooding control operation could weaken the barrier effect of the dam on MPs. Further, based on the conditional fragmentation model, the PE fragments in SMPs of the TGR remained at a stable state. MPs in the TGR mainly originated from anthropogenic activities (wastewater, containers, and agriculture films), with atmospheric deposition as a potential transport pathway for polymers. Our study demonstrates that dam operation during the flood period can influence the MP organization in TGR, providing new insights of the global land-sea transportation of MPs in the Yangtze River.

Structure and Functionality of the Mesozooplankton Community in a Coastal Marine Environment: Portofino Marine Protected Area (Liguria)

This research is part of the LTER (Long-Term Ecological Research) project, a network of terrestrial, freshwater, transitional water and marine sites, on which ecological research is conducted on a multi-decade scale. LTER studies ecosystems, their dynamics and evolution, the relationships between biodiversity and ecological functionality, water quality, productivity, the role of resource availability, the effects of pollution and climate change. The research focuses on the study of the variability of zooplankton groups in the Portofino marine protected area, in Punta Faro. The samplings were carried out in the years 2018–2019, and the results were compared with the values of the years 2003–2005, interesting from a meteorological climatic and biological point of view. The plankton community of the Punta Faro system was analyzed by means of a modeling approach to obtain information on the functionality and health status of the system and to verify whether this has undergone any alterations in the last decade. The analyses carried out show a clear difference between the three-year period 2003–2005 and the two-year period 2018–2019, highlighting how environmental changes, such as the increase in temperature, have led to higher costs of system functioning in the last two years. The mesozooplankton community has changed both in terms of abundance of organisms and in terms of organization and functionality.

Poly- and Perfluorinated Alkyl Substances in Air and Water from Dhaka, Bangladesh.

Bangladesh hosts extensive textile manufacturing, for some of which per- and polyfluorinated alkyl substances (PFAS) have been used to impart water and dirt repellency, among other things. Textile waste emissions to the atmosphere and discharge into rivers and other bodies of water could present a significant concern for human and ecosystem health, but there is little information on PFAS in Bangladesh. To assess the presence of ionic PFAS and their precursors in air and water from Dhaka, Bangladesh, polyethylene sheets were deployed for 28 days as passive samplers for neutral PFAS in outdoor air and water, while ionic PFAS were measured from discrete water grabs. Fluorotelomer alcohols (FTOHs) were detected at almost all sites in air and water; the most frequently detected compound was 6:2 FTOH, ranging from below instrumental detection limits (<IDL) to 70 ng m-3 in air and from <IDL to -19 ng L-1 in water. Of the ionic PFAS, perfluorobutanoic acid (PFBA), perfluorohexanoic acid, perfluorooctanoic acid, perfluorohexane sulfonic acid, and perfluorooctane sulfonic acid dominated in frequency of detection and magnitude, with concentrations ranging from 1.8 to 19.0 ng L-1 in surface waters. The prevalence of 6:2 FTOH and PFBA across sites probably reflects their use in textile manufacturing and could indicate the industry's switch to shorter-chain PFAS alternatives. Environ Toxicol Chem 2022;41:334-342. © 2021 SETAC.

Estimating actual evapotranspiration at field-to-continent scales by calibrating the CMRSET algorithm with MODIS, VIIRS, Landsat and Sentinel-2 data

Actual evapotranspiration (ETa) can be estimated using optical remote sensing and meteorological data. Herein we calibrated and applied the CMRSET (CSIRO MODIS Reflectance-based Scaling EvapoTranspiration) model at the continental scale in Australia using five remotely sensed data products with spatial resolutions ranging from 500 m (MODIS, VIIRS), 30 m (Landsat) to 20 m (Sentinel-2), and temporal frequencies ranging from daily (MODIS, VIIRS) to multi-days (Landsat and Sentinel-2). The five remotely sensed data products were used to compute a crop factor (kc) based on two vegetation indices which modify Priestley-Taylor potential evapotranspiration estimates (ETp; calculated from nation-wide daily meteorological grids) to obtain ETa. CMRSET was calibrated using daily latent heat observations from 30 eddy covariance flux towers located across Australia, representing a wide variety of land covers and climates. To ensure that CMRSET adequately estimated open water evaporation, daily ETp estimates at six water sites were also added in the calibration network. The calibrated CMRSET model was able to estimate daily ETa observed at the flux towers with a relative Root Mean Squared Error (rRMSE)/coefficient of determination (R2) ranging between 0.15/0.96 (with Sentinel-2) to 0.26/0.93 (VIIRS). Additionally, we independently evaluated the performance of CMRSET by comparing the long-term (5 years or more) differences between mean annual precipitation and ETa with measured streamflow at 638 unimpaired catchments across Australia. The comparison showed a RMSE of 0.50 mm·d-1 (rRMSE of 0.26) and a R2 of 0.70. The CMRSET model performed better than or similarly when compared against two global ETa products based on MODIS optical and thermal data. Extending the suite of remotely sensed data products that CMRSET is calibrated with and using a network of sites located across vast climate and geographic ranges, means that CMRSET can now be used to estimate ETa at continental scales with multiple spatial resolutions and temporal frequencies. Compared to other available ETa products, CMRSET is more straightforward to operationalise, requires less data inputs, can capture ETa dynamics in areas with significant direct evaporation such as floodplains and lakes and does not require manual calibration to detect wet and dry pixels.

Topology of the sacred and agency

On the background of resurging interest in ‚sites of power’, on both sides of the Atlantic, this essay presents a feature, sometimes marginalised in their theories: ‘agency’. It is understood that the recognition of the relation between ‘topography’ and ‘agency’ is required, to understand the dynamics of such sites, as experienced and codified in cultures and religions. This essay focusses on the ‘sites of water’ as important archetypes of Bantu African and Brazilian Diaspora cultures and religions. On the assumption of ancient formative connections of the Bantu with the Afro-Asiatic cultures, to which the Hebrew belongs, corresponding reports and concepts from the Bible are included in this analysis, disclosing systematically interesting features on this matrix by ‘archaeology of culture’.