Input Of Pollutants Research Articles

The Autobot-WQ: A portable, low-cost autosampler to provide new insight into urban spatio-temporal water quality dynamics

Urbanization and the increase in urban land cover are growing concerns associated with numerous negative impacts on surface water quality. Currently, many emerging contaminants are difficult to measure with no field deployable sensors currently available. Hence, discrete grab samples are required for subsequent laboratory analysis. To capture the spatiotemporal variability in pollution pulses, autosamplers can be used, but commercial offerings are both expensive and have a large footprint. This can be problematic in urban environments where there is a high density of point source inputs and risk of vandalism or theft. Here, we present a small and robust low-cost autosampler that is ideally suited for deployment in urban environments. The design is based on “off the shelf” open-source hardware components and software and requires no prior engineering, electronics, or computer programming experience to build. The autosampler uses a small peristaltic pump to enable collection of 14 small volume samples (50 mL) and is housed in a small footprint camera case. To illustrate the technology, we present two use cases for rapid sampling of stormwater pulses of: 1) an urban river channel and 2) green roof runoff. When compared with a commercial autosampler, our device showed comparable results and enabled us to capture temporal dynamics in key water quality parameters (e.g., dissolved organic matter) following rain events in an urban stream. Water quality differences associated with differing green roof design/maintenance regimes (managed and unmanaged vegetation) were captured using the autosampler, highlighting how unmanaged vegetation has a greater potential for mitigating the rapid runoff and peaked pollutant inputs associated with impervious surfaces. These two case studies show that our portable autosampler provides capacity to improve understanding of the impact of urban design and infrastructure on water quality and can lead to the development of more effective mitigation solutions. Finally, we discuss opportunities for further technical refinement of our autosampler and applications to improve environmental monitoring. We propose a holistic monitoring approach to address some of the outstanding challenges in urban areas and enable monitoring to shift from discrete point sources towards characterization of catchment or network scale dynamics.

Spatiotemporal variation in water quality and identification and quantification of areas sensitive to water quality in Hulun lake, China

This study aimed at characterizing the spatiotemporal variability in water quality in Hulun Lake. In an attempt to assess the water quality status of the lake, data acquired from 13 monitoring points in Hulun Lake from 2012 to 2020 was applied to the improved composite water quality identification index (WQI). The ordinary least squares (OLS) model was used to identify areas of the lake vulnerable to water pollution. The results showed an increase in the WQI value of Hulun Lake and the water quality deteriorated during 2012–2016. The water quality began to improve gradually in 2017. The main variable affecting water quality in the lake transitioned from chemical oxygen demand (CODcr) and total nitrogen (TN) to CODcr and total phosphorus(TP). This shift in major pollutants was an important factor contributing to deterioration in water quality. Seasonal differences in water quality may be attributed to migration of pollutants [CODcr, total dissolved solids (TDS)] to the subglacial water column during the ice-covered period and the subsequent blocking effect of the ice cap. A spatially based OLS model identified the critical impact of Chl.a on water quality. Water transfers were identified as a major factor contributing to an improvement in water quality and to pollutant transformation and contributed to increase in the water quality sensitive area. Despite recent efforts to improve the water quality of Hulun Lake, input of exogenous pollutants, increase in endogenous pollutants, as well as the anaerobic conditions of the ice layer pose significant challenges to the management of Hulun Lake. The implementation of pollutant control measures are, in particular, recommended on the northwest shore for managing the water quality of the lake.

Risk evaluation and prioritization of contaminants of emerging concern and other organic micropollutants in two river basins of central Argentina

A research gap exists in baseline concentrations of organic micropollutants in South American rivers. Identification of areas with different degrees of contamination and risk to the inhabitant biota is needed to improve management of freshwater resources. Here we inform the incidence and ecological risk assessment (ERA) of current used pesticides (CUPs), pharmaceutical and personal care products (PPCPs) and cyanotoxins (CTX) measured in two river basins from central Argentina (South America). Risk Quotients approach was used for ERA differentiating wet and dry seasons. High risk was associated to CUPs in both basins (45 % and 30 % of sites from Suquía and Ctalamochita rivers, respectively), mostly in the basins extremes. Main contributors to risk in water were insecticides and herbicides in Suquía river and insecticides and fungicides in Ctalamochita river. In Suquía river sediments, a very high risk was observed in the lower basin, mainly from AMPA contribution. Additionally, 36 % of the sites showed very high risk of PCPPs in Suquía river water, with the highest risk downstream the wastewater treatment plant of Córdoba city. Main contribution was from a psychiatric drug and analgesics. In sediments medium risk was observed at the same places with antibiotics and psychiatrics as main contributors. Few data of PPCPs are available in the Ctalamochita river. The risk in water was low, with one site (downstream Santa Rosa de Calamuchita town) presenting moderated risk caused by an antibiotic. CTX represented in general medium risk in San Roque reservoir, with San Antonio river mouth and the dam exit showing high risk during the wet season. The main contributor was microcystin-LR. Priority chemicals for monitoring or further management include two CUPs, two PPCPs, and one CTX, demonstrating a significant input of pollutants to water ecosystems from different sources and the need to include organic micropollutants in current and future monitoring.

Distribution and accumulation of heavy metals in the catchment catenary complex and bottom sediments of the water body in an urban environment

Problem Statement. The pollutant intake into water bodies is one of the issues of urban areas. The pollutant input from the residential area of the city with surface runoff can many times exceed the input of pollutants from industrial and recreational areas, as well as from point pollutant sources. The objective of the study is 1) assess the distribution of chemical elements in catchments of water bodies in an urbanised area, 2) accumulation of chemical elements in solid matter of bottom sediments of surface water bodies with catchments in the functional areas of the city, 3) identify the main mechanisms of transfer of elements in solid matter from catchments to water bodies. The study was conducted on the example of Ekaterinburg (Russia). The material for the study consisted of the results of a landscape environmental and geochemical survey carried out in the city area in 2019–2021. Results. The distributions of element concentrations between functional landscape zones in the catenaries of the Kharitonovsky Garden and Chemodanchik reservoir catchments in Ekaterinburg were obtained. The distributions of metal concentrations in the catchment components show a tendency for the transfer of substance of different origin from the landscape components by lateral migration flows to the local basis of denudation (a drainless surface water body). At the same time in the bottom sediments of the reservoir there is a multiple accumulation of both pollutants and elements of typomorphic association. Dust fractions are the main carrier of contaminants in catchments.

Availability of Se-rich Arable Land in High Geological Background Area and Suggestions for Zoning

In order to promote the results of land quality geochemical surveys to serve the development of characteristic land resources and realize the safe utilization of Se-rich resources in high geological background areas, Wuli Town, Qianjiang District, Chongqing City were taken as the research object to evaluate the Se-rich level and heavy metal content of soil crops and carry out research on Se-rich cultivated area division and the availability method system in the high geological background area, in order to improve the utilization efficiency of Se-rich resources and provide ideas for the safe utilization of Se-rich resources in high geological background areas. The results showed that the soil and crops in the study area were rich in Se and had the potential to develop Se-rich resources, but some samples had the problem of excessive Cd. Soil pH was a key factor affecting the content of Se and Cd in crops, and alkaline conditions were conducive to the safe utilization of Se-rich resources. The areas of Class A-E (A:selenium-enriched arable land, B:crops that were not selenium-enriched but were safe, C:crops that were selenium-enriched but unsafe, D:crops that were not selenium-enriched and unsafe, and E:soil selenium content less than the selenium-enriched threshold and soil heavy metals not exceeding the standard)cultivated land were 0.72, 0.75, 0.28, 0.13, and 0.56 km2, respectively. It is recommended to develop safe and Se-rich resources in the distribution area of Class A cultivated land and to carry out soil acidification conditioning and low-accumulation crops in the distribution area of Class C and D cultivated land; other agronomic measures should be taken to reduce the risk of excessive heavy metals in crops and strengthen the protection of cultivated land in the region to prevent the input of new pollutants.

Distribution, remobilization and accumulation of organic contaminants by flood events in a meso-scaled catchment system

BackgroundExtreme weather events and natural disasters such as floods can cause severe damage and impacts on catchment systems covering natural as well as urban, industrial or agricultural areas. Thus, floods often lead to the acute and unusual release of organic pollutants, as well as the remobilization of legacy contaminations or old burdens. Floodplains are then of major relevance for the accumulation of pollutants. Accordingly, various floodplains distributed throughout the course of the Rur River were sampled immediately after two flood events in January/February and July 2021. The main objective was to address the general lack of knowledge on indirect effects of flooding and the corresponding distribution and accumulation of organic pollutants regarding different dimensions and dynamics of flood events.ResultsGas Chromatography/Mass Spectrometry (GC/MS) based non-target screenings revealed the presence of several lipophilic to moderate polar organic pollutant groups, including PAHs (polycyclic aromatic hydrocarbons), hopanes, PCBs (polychlorinated biphenyls), LABs (linear alkylbenzenes) and various other industrial substances. These substances are indicators of petrogenic pollution, historical and current industry in the catchment area, and of wastewater and urban pollution, respectively. In general, concentrations detected after the extreme summer flood were higher than in winter. This points to additional emission sources due to substantially higher discharges and consequently more severe flooding in July. The main tributaries also had a major influence on the input and concentrations of organic pollutants at the receiving Rur River. Further on, structural features such as dams and reservoirs, but also (re)naturalized areas were clearly recognizable in the flood-related dispersion of organic pollutants. Interestingly, LAB contamination was similar after both flood events regardless of the specific dimension.ConclusionsFlood dimension and frequency are of great relevance for the distribution, remobilization and accumulation of organic contaminants. However, special attention should be given to the introduction of wastewater pollutants for any flood extent. Overall, organic indicators are therefore very useful to obtain information on specific distribution patterns and the influence of tributaries or structural measures, providing an important basis for the assessment of short- and long-term environmental risks and hazards.

Moisture expansion of tuff stones and sandstones

Volcanic tuffs and sandstones have been used as natural building stones in the construction of monuments and buildings over the millennia of human history. Progressive weathering over time (e.g., temperature fluctuations, moisture uptake, variations in humidity, precipitation, the input of modern-day pollutants or salt crystallization) lead to damages in the internal structure of the stone. Scaling and layer-parallel flaking of rock fragments result from these types of damage-causing processes, especially when swellable clay minerals are present that lead to the generation of stresses in the rock fabric. Tuff and sandstone samples that exemplify these types of damages are investigated in this study, which were used in the construction of cultural heritage sites in Armenia, Mexico, Germany and Switzerland. Comparisons are made between these rock types considering that they show strong variations in fabric heterogeneity, grain sizes, mineralogical composition (e.g., swellable clay- and zeolite-bearing minerals), and visible macroscopic features such as depositional layering. Comprehensive investigations have been carried out that include detailed petrographic analyses, XRD analyses for the determination of the swellable and non-swellable clay fraction and minerals of the zeolite group, the cation exchange capacity (CEC), detailed SEM surveys for determining the type and localization of clays and zeolites in the rock fabric, as well as defining the petrophysical properties (e.g., porosity, capillary water uptake, water absorption, hydric expansion and mechanical properties). Moreover, this study explores the possible interaction between swellable clay minerals and zeolites (mordenite, heulandite/clinoptilolite) by conducting swelling experiments with salts and solvents and fluid-exchange experiments with and without the presence of zeolites. To explain the damages caused by the expansion in the tuffs and sandstones, two principle modes of moisture expansion are discussed when swellable clay minerals are present in the rock. These are dominantly inner or intracrystalline swelling, and secondarily, intercrystalline or osmotic swelling. When no swellable clay minerals are present, the study explains the damages in tuffs and sandstones as the result of disjoining pressure, where a high percentage of microporosity plays a pivotal role.

Polybacterial shift in benthic river biofilms attributed to organic pollution – a prospect of a new biosentinel?

Abstract Organic pollution continues to contaminate river water and degrade aquatic ecosystems worldwide. In heavily modified river systems with high organic loading, sewage fungus, a heterotrophic biofilm, can form on the riverbed. The aim of this study was to determine how the polybacterial community of riverbed biofilms changes prior to and during a sewage fungus outbreak to inform the development of novel biomonitoring approaches. Riverbed biofilm samples were collected from a site that experienced sewage fungus outbreaks previously and an upstream control, following a BACI design. The polybacterial community was characterized using targeted amplicon sequencing (16s rRNA). The results indicate that the community became dominated by two genera prior to and during the sewage fungus outbreak, Rhodoferax and Sphaerotilus, which accounted for 32.8 and 14.2% of the relative abundance. When aggregated at a higher taxonomic level, the genetic data show that the community was comprised largely of bacteria from a single family, Comamonadaceae, totalling 64.1% of the relative abundance. Statistically significant differences in the polybacterial community over time and between impact and control sites provide initial evidence that genetic-based fingerprinting could be a promising biosentinel approach to identify organic pollution inputs and monitor their ecological impact.

Determination of Critical Loads for Eutrophying and Acidifying Air Pollutant Inputs for the Protection of Near-Natural Ecosystems in Germany

Under the Convention on Long-Range Transboundary Air Pollution (CLRTAP) of the UN Economic Commission for Europe, UNECE, to which Germany acceded in 1982, the harmful effects of air pollutants on the environment are to be steadily reduced and ultimately limited to a level that is compatible with nature. The ICP Modelling & Mapping (ICP M&M) under the Working Group on Effects (WGE) of CLRTAP maps critical loads for the entire Convention area and calculates the exceedance risks and associated risks to vegetation and biodiversity. A current data request was made in November 2015 with the aim of submitting new or updated ecosystem-specific critical loads for protection against acidification and eutrophication. For this task, critical loads were determined by the authors for one third of the territory of Germany using the simple mass balance (SMB) method according to the ICP Mapping Manual. The permissible eutrophying nitrogen input into the ecosystem CLnut(N), as well as the acidifying sulphur input CLmaxS, can be described as the setting of the equilibrium between substance inputs and outputs, provided that specific critical limits are met. The BERN database—created by the authors—serves as the basis for modelling vegetation-specific critical limits as a complement to the SMB model. The BERN database contains near-natural plant communities with clearly definable site constancy. The 25,600 German and a further 24,600 European vegetation records dating back to before 1960 were evaluated to determine the good ecological status of the plant communities. The results of the critical load calculation show that about half of the receptor areas have critical loads for eutrophying nitrogen below 10 kg ha−1 a−1 and critical loads for acidifying sulphur were below 1500 eq ha−1 a−1. It could be demonstrated that the BERN–SMB-modelled critical loads for eutrophying nitrogen inputs show lower values on average throughout Germany than those calculated using only the previous critical limits according to the ICP Mapping Manual. These values are closer to the empirical critical loads than the critical loads without BERN data. For the goal of the German National Biodiversity Strategy by 2007 and 2020 to define ecosystem-related impact thresholds for pollutants that describe the effects on biodiversity, the BERN/SMB critical loads for the protection of ecosystems provide a precautionary scientific basis.

Occurrence and source of PAHs in Miankaleh International Wetland in Iran

We examined the occurrence and sources of 16 priority PAHs in the water and sediment samples of the Miankaleh Wetland (Coastal Biosphere Reserve), famous for harbouring huge flocks of migrating birds. The water and sediment samples collected from various locations were visualized and processed using a self-organizing map, positive matrix factorization and GIS. All the sediment samples, and >90% of the water samples, showed some degree of PAHs contamination. Higher PAH levels occur near the Chopoghi Channel, powerplants, sewage outfalls, and near fishing operations. Compared with previous study in this area, the PAHs concentration in the sediments of aquatic ecosystem of Miankaleh Wetland is increasing. The levels of PAH contamination seem too low to account for the mass deaths of migratory birds, and botulinus contamination seems the likely cause. Fugacity calculations show that the sediments act as a sink for PAHs. According to PMF and SOM analyses, three origins of PAHs were recognized: (i) fossil fuel and vehicular emissions with high-molecular weight PAHs (4–5 ring); (ii) municipal and industrial sewages characterized by low-molecular weight PAHs (2–3 ring) typical of petrogenic sources; and (iii) port activity characterized by prevalence of petrogenic influence and petroleum-related activities (combustion PAHs and low-molecular weight PAHs) consistent with port activity. This wetland needs serious attention because of continuous input of pollutants. The results and the methods used in this study may assist in improving coastal wetlands management.

Fractionation of toxic metal Pb from truly dissolved and colloidal phases of seaward rivers in a coastal delta

Colloids of natural river water is a key intermediate carrier of lead (Pb). It is important to monitor the transport–transformation behavior of Pb in the colloidal phase of seaward water because this behavior is related to the levels of pollution input and environmental risks posed to the sea, especially in coastal delta areas. In this study, the fractionation behavior and distribution of toxic Pb from the truly dissolved phase and the different colloidal phases in seven seaward rivers in the Yellow River Delta were investigated. The concentrations of total dissolved Pb, truly dissolved Pb, and colloidal Pb were 0.99–40.09 μg L–1, 0.40–8.10 μg L–1, and 0.60–35.88 μg L–1, respectively. In freshwater rivers, the main component of total dissolved Pb (about > 50%) is truly dissolved Pb but the main component of total dissolved Pb in the seawater environment is colloidal Pb (> 80%). A dramatic increase in salinity causes the deposition (about ≈94%) of all forms of Pb to sediment from estuarine water in winter. However, this sedimentation behavior of colloidal Pb gradually decreases (in the Shenxiangou River) when the river salinity approaches seawater salinity (S = ≈29). In the industrial port (Xiaoqinghe River) and mariculture (Yongfenghe River) estuarine areas, which have extensive seawater, the deposition behavior of colloidal Pb (<15%) is less affected by the change in salinity. This suggests that human activity contributes to the spread of Pb in the offshore environment. The concentration of 100 kDa–0.22 μm Pb has a postive correlation with total colloidal Pb. Its variation is minimally affected by salinity compared with other colloidal components. In addition, the correlation between the molecular weight and aromaticity of chromophoric dissolved organic matter (CDOM) and colloidal Pb suggests that macromolecules in seawater will be important transport carriers of Pb. In all, truly dissolved Pb is the main transport form of dissolved Pb in river freshwater; however, in brackish water in estuaries, colloidal matter gradually becomes the main transport carrier. Surging salinity immobilizes truly dissolved Pb in the estuarine region, but colloidal matter inhibits this deposition. Colloidal phase is the important conversion for land–sea transport of Pb by seaward rivers.

Variations in dissolved oxygen and aquatic biological responses in China's coastal seas

Coastal areas can represent an ecological transition zone with the function of biodiversity conservation, and good water quality is fundamental to maintaining this function. In this study, we analyzed data from 2011 to 2020 to reveal the variation in dissolved oxygen (DO) and the aquatic biological response in China's coastal seas. Results showed that DO in coastal waters exhibited an upward trend from 2011 to 2020 because of reduction in terrestrial anthropogenic pollutant (TAP) input. In comparison with DO in other seas, the DO content in the East China Sea was lower owing to higher TAP input, i.e., the proportion of DO of <5 mg L−1 accounted for approximately 60% of the total. Species numbers, density, and the species diversity index of phytoplankton, zooplankton, and macrobenthos were different in the different sea areas because phytoplankton, zooplankton, and macrobenthos have different responses to changes in DO. In comparison with the species numbers of zooplankton and macrobenthos, the species numbers of phytoplankton were more significantly related to DO, and showed a negative linear relationship with a better DO environment (DO ≥ 5 mg L−1; r2 = 0.39, p < 0.01) and positive correlation with a poor DO environment (DO < 3 mg L−1; r2 = 0.52, p < 0.01). A better DO environment is conducive to increased density of macrobenthos. Studies have shown that a good DO environment contributes to coastal ecosystem health, and continuous control of TAP input is an effective means of ensuring DO recovery.

The response of freshwater plankton communities to temporal concurrence of agrochemical mixtures

Freshwater ecosystems regularly experience pulsed inputs of nutrients and other pollutants as a result of temporally variable applications of agrochemicals combined with runoff events. In this study, we evaluate how planktonic communities respond to repeated and pulsed insecticide disturbances and if the response depends on temporal concurrence with nutrient pulses. We conducted an experiment using mesocosms to assess the ecotoxicological effects of a commonly used insecticide (chlorpyrifos) and nutrients (nitrogen and phosphorus) on plankton communities. The mesocosms (300 L) were established outdoors for 10 weeks. The experiment consisted of 3 treatments: nutrient pulse of nitrogen and phosphorus every two weeks (N; considered as control), nutrients and insecticide pulsed simultaneously every two weeks (NI), and nutrients and insecticide pulsed in alternating weeks (N_I). Insecticide and nutrient pulses consisted of 2 μg/L of chlorpyrifos, 560 μg/L of nitrogen, and 39.9 μg/L of phosphorus. Zooplankton abundance, community structure, and diversity were used as structural indicators. Chlorophyll a and net production were used as functional indicators. We found no effect of the treatments on zooplankton abundance, while richness and Shannon diversity was lower in treatments with pulsed insecticide (NI and N_I) compared to control treatment (N). Phytoplankton biomass was higher in the treatments with insecticide than in the controls (N). Higher phytoplankton biomass could be explained by an indirect effect shift from a cladocera-dominated to a copepod-dominated community in response to the insecticide treatment. Overall, the insecticide disturbance had direct and indirect effects on the community and did not depend on whether insecticides were pulsed synchronously or asynchronously with nutrients.

Photocatalytic degradation of air pollutant by modified nano titanium oxide (TiO2)in a fluidized bed photoreactor: Optimizing and kinetic modeling

Volatile organic compound (VOC) removal by photocatalytic oxidation (PCO) is the practical and economical process to reduce air pollutants. Many conditions, such as temperature, initial concentration of VOC, relative humidity, gas flow rate, and light intensity, affected this process. Therefore, finding the optimal operating conditions for the PCO process can increase the efficiency of the process and also operate the process more economically. Also, it is possible to scale up the process with more confidence by the kinetics modeling of the process and finding the rate constants. In this study, the effect of gas flow rate, light intensity, and VOC inlet concentration were investigated. The results show that the flow rate of 15 lit/min is more efficient, and the effect of the pollutant input concentration and light intensity directly affects the conversion percentage. The kinetic study of acetaldehyde removal was investigated in the fluidized bed reactor, and the best kinetic model was proposed based on reactor model regression on the outlet concentration data. The best model describes a langmuir-hynshelwood type model with adsorbed acetaldehyde's inhibition effect on the catalyst's surface. The R2 coefficient for the best kinetic type is 0.98.

Evaluation of a Modular Filter Concept to Reduce Microplastics and Other Solids from Urban Stormwater Runoff

This paper describes an innovative Decentralized Technical Sustainable Drainage System (SuDS) concept, which is based on technical devices, such as sieves, sedimentation barriers, floating barriers and a magnetic module, which addresses, mainly, the fine matter. The SuDS is designed as a retrofit system so that no costly and time-consuming conversion measures are necessary. Due to the possibility of free configurability of individual modules in the three levels, road, gully and drain, a novel solution approach is presented, which is not available on the market, for a reduction in solids in general and microplastics in particular. The retention performance of selected modules and their combinations is demonstrated by means of bench tests according to the test procedure of the German Institute for Construction Engineering (DIBt) for the evaluation of decentralized treatment systems. Four different rain intensities, from light to medium up to heavy rain, are charged to the filter modules. Collected and fractionated road-deposited sediment (RDS) was selected as the test substance (10 kg). Additional tests with tyre powder, PE pellets, cigarette butts and candy wrappers helped to make clear the filter process of the particulate matter. The retention performance was determined by the mass balance between the defined dosage and at the outlet. For this purpose, the total volume flow of the effluent was passed over a stainless-steel sieve with a diameter of 600 mm and a mesh size of 20 µm. For the test substance, RDS retention rates up to 97% were measured. Very fine matter, particularly, was technically challenging to obtain; &lt;63 µm up to 66% could be retained by the filter modules. Modules in the road space, such as porous asphalt or additional retention spaces, in the area of the curb as well as direct infiltration in the road drainage shaft are theoretically described and discussed. The outlook also addresses the potential of an intelligent network to reduce the input of pollution from urban stormwater runoff.

Long-term Succession Patterns and Driving Factors of Water Quality in a Flood-pulse System Lake: A Case Study of Lake Luoma, Jiangsu Province

Lake Luoma is an important storage lake for the Eastern route of the South-to-North Water Diversion Project (NSBD), which has many functions including flood control and irrigation, drinking water supply, and ecological maintenance. In order to understand the succession patterns and driving factors of water quality in Lake Luoma, we used monthly monitoring data from 2009 to 2020 in combination with historical data from 1996 to 2008. The long-term succession patterns, seasonal dynamics, and spatial patterns of total nitrogen (TN), total phosphorus (TP), permanganate index, and ammonia nitrogen (NH+4-N) were examined, and the influence of meteorological and hydrological factors on water quality was explored through correlation analyses and generalized additive models. The results showed that it remained in the status of grade Ⅳ-inferior Ⅴ over the past 25 years. The concentration of TN, which was the main pollutant, changed significantly (1.06-3.49 mg·L-1), experiencing three stages of gradual decline (1996-2002), significant interannual fluctuation (2002-2015), and significant increase (2015-2020). Permanganate index decreased significantly (2.97-6.38 mg·L-1), whereas TP and NH+4-N concentration fluctuated slightly, ranging from 0.024-0.076 mg·L-1 and 0.11-0.69 mg·L-1, respectively. The concentration of TN and TP increased abnormally in the summer of 2017-2020, reaching 3.30 mg·L-1 and 0.14 mg·L-1 in August, respectively, which was approximately 1.5 and 2.4 times the annual average. In terms of seasonal dynamics, the seasonal variation in water quality between summer/autumn and winter/spring reversed after 2015, with water quality in summer/autumn being worse than that in winter and spring, indicating the exacerbation of eutrophication. The water quality in the southern area was obviously better than that in the northern area. The input of pollutants from the Yihe River and Middle Canal increased with water quantity since 2015, which drove the water quality deterioration through nutrients. Our results suggested that the water quality of Lake Luoma should be improved by strengthening exogenous pollution reduction, endogenous control, polder dismantling, and ecological restoration.

Environment from A to Z, from Air to Zero waste

First and foremost, I would like to thank all supporters of the journal, that is, all authors who submit and publish their contributions in CLEAN – Soil, Air, Water, all reviewers who invest time and put submitted articles through their paces, and, of course, all readers who make contributions really come alive. Thank you all for helping to shape the journal. Today I start with this editorial a small series “Environment from A to Z, from Air to Zero waste”. The world we live in is unique as far as we know and so we should strive to preserve this one world. In this journal we will find articles that 1) look at data on air, soil, and water quality and 2) offer solutions for a cleaner environment. Everything from A to Z. A for Air, which we need to live. Air that we breathe and that should be free of pollutants so that we stay healthy. On the one hand, we have to monitor the air quality to know how clean the air is that surrounds us. On the other hand, we then need to use that knowledge to take the necessary actions to ensure that the air is kept clean. B for Biofuels, which is obtained from processed or refined biomass. Combustion of biofuels produces CO2, which is in turn absorbed and stored by plants, thus restarting the cycle of biomass production and use. C for Climate change, which is already being discussed publicly. We are already seeing some of the effects with extreme weather, forest fires, thawing permafrost, and so on. How can we mitigate overheating in cities or channel or use rainwater/stormwater better, what form of land use is promising, what are the possibilities for CO2 fixation, and many other questions we have to ask ourselves and find answers for. D as in Drinking water, the gold of tomorrow, an elixir of life without which we cannot exist. Keeping drinking water clean and, above all, supplying it to people, animals and plants is a Herculean task. Extreme weather conditions in all regions of the world sometimes present us with almost unsolvable problems: Inputs of pollutants through flooding or salinization of soils and thus also of water during prolonged periods of drought. E for E-waste. Electrical devices that are no longer used, whether broken or functional but technically outdated, accumulate by the ton every year. A plague, if you will. But we can also view this scrap as a resource and find new ways to obtain valuable materials such as precious metals. CLEAN covers all aspects of sustainability and environmental safety including those mentioned here under the first five letters of the alphabet. Do you have submissions that address environmental sustainability issues such as air pollution, waste management, water cycle and environmental protection? I look forward to receiving your submission in CLEAN. More on the letters F through I/J in the next editorial. I wish you a good and successful 2023. Stay healthy. Yours sincerely, phenheik@wiley.com

Environmental and immunonutrition effects on public health linked to water pollutants and fish disease

Freshwater aquatic environment are indeed in a bad state worldwide, due to human activities and there is an urgent need to save them and their biodiversity. Water plays a key role in diluting pollutants and because of that superiority as a solvent, it also means that water-soluble wastes pollute water easily. For instance, runoff from nearby lands provides freshwater life zones with an almost constant input of organic material, inorganic nutrients, and other pollutants. These cause undesirable changes in the physicochemical or biological factors of ecosystem, which in turn directly or indirectly affect the ecological balance of the environment, and ultimately affect human beings. And also advances in culture techniques and the introduction of new species have contributed to the rapid growth of the aquaculture industry. However, treatment methods including approved antibiotics and chemotherapeutants are directly or indirectly affected the consumer/environment-friendly. This review paper tried to indicate how agricultural activities and unbalanced fish nutrition affect fish health and water quality at large the environment.

Spatial Risk Assessment and Source Identification of Heavy Metals in Riverine Sediments of Lake Chaohu Basin, China

In recent decades, the rivers in Lake Chaohu Basin have been subjected to intensive anthropogenic disturbance. However, previous studies have mainly focused on Lake Chaohu, and the inflowing and outflowing rivers have not been well examined. To characterize the pollution status of heavy metals in the entire Lake Chaohu Basin, 8 heavy metals (Cu, Zn, Pb, Cr, Cd, As, Hg, and Ni) in riverine surface sediments were measured at 131 sampling sites in 7 subbasins. Spatial patterns and pollution characteristics were evaluated based on the potential ecological risk, geoaccumulation, and pollution load indexes. The results showed that Cr and Hg were the 2 main heavy metal pollutants in the surface sediments, with mean contents exceeding background values by a factor of 4.12 and 2.64, respectively. The Nanfei River (NF), which flows through Hefei city (a metropolis of the capital of Anhui Province), is characterized by large amounts of domestic and industrial waste discharged into the water body due to human activities; this waste caused serious heavy metal pollution, and NF substantially contributed to heavy metal pollution inputs to Lake Chaohu. Several subbasins in the southern part of Lake Chaohu Basin exhibited high concentrations of Cu in surface sediments, mainly from mining and agriculture. This study identified the main contamination areas, revealed the possible sources of each heavy metal, and can serve as a reference for the remediation and management of Lake Chaohu Basin to ensure the water safety of Lake Chaohu.

Organochlorine pesticide residues in water, sediments and Nile tilapia (Oreochromis niloticus) of Lake Nakuru, Kenya and implications for its fishery

AbstractThe present study was conducted to assess the levels of selected organochlorine pesticide (OCP) residues in water, sediments and Nile tilapia, as well as the potential health risks to humans who consume the fish of Lake Nakuru. Nine composite water and nine sediment samples, as well as 30 fish specimens, were collected from five representative sampling sites within Lake Nakuru. The OCPs targeted in the present study included p,p′‐Dichlorodiphenyl dichloroethane (p,p′‐DDD), p,p′‐dichlorodiphenyldichloroethylene (p,p′‐DDE), p,p′‐dichlorodiphenyltrichloroethane (p,p′‐DDT), heptachlor, heptachlor epoxide, α endosulfan (1), β endosulfan (2), endosulfan sulphate, endrin, lindane, aldrin, dieldrin, methoxychlor and hexachlorocyclohexanes (alpha; beta; gamma; delta). Except for aldrin, all 16 OCPs targeted in the present study were detected. The OCP residue levels ranged from below detection limit (BDL) to 7.44 ± 0.66 μg/L, BDL to 6.39 ± 1.10 μg/kg ww and BDL to 319.74 ± 66.94 μg/kg ww in water, sediment and fish samples respectively. Some OCP concentrations exhibited significant differences across the sampling sites (p &lt; .05). The residue level of endosulfan was above the European Union standard, whereas the target hazard quotient of heptachlor epoxide was above 1, therefore being unsafe for human consumption. The present study results indicate that most of organochlorine pesticides though banned in Kenya are still detected in the environment, posing potential long‐term health hazards to humans. Accordingly, environmental monitoring programme and mitigation strategies of reducing pollutant inputs into the lake is recommended, as well as an immediate ban on harvesting and consumption of fish from Lake Nakuru.