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Several dengue epidemics recently occurred in La Reunion, an island harboring two dengue viruses (DVs) vectors: Aedes albopictus, and Ae. aegypti, the former being the main local DV vector. Aedes aegypti shows a peculiar ecology, compared to other tropical populations of the same species. This study aimed to provide researchers and public-health users with locally validated oviposition traps (ovitraps) to monitor Aedes populations. A field experiment was performed in Saint-Joseph to assess the effect of different settings on the detection probability and apparent density of Aedes mosquitoes. Black plastic ovitraps were identified as the best choice. Vacoa trees (Pandanus utilis) were the only observed breeding sites for Ae. aegypti, shared with Ae. albopictus. They were the experimental units in a Latin square design with three factors: trap position in the trees (ground vs canopy), oviposition surface in the trap (blotting paper vs. vacoa leaf), and addition of organic matter to the trap water. The latter factor was found unimportant. On the ground, Ae. aegypti eggs were only found with vacoa leaves as the oviposition surface. Their detection and apparent density increased when ovitraps were located in the tree canopy. The main factor for Ae. albopictus was the oviposition surface, with a preference for blotting paper. In all trap settings, their detection was close to 100%. Larval survival was lower for a high egg density, combined with blotting paper as the oviposition surface. When monitoring mixed Aedes populations in La Reunion, we recommend using black plastic ovitraps, placed at 1.50-to-2.00-m high in vacoa trees, with vacoa leaves as the oviposition surface. [ABSTRACT FROM AUTHOR]

In order to realize rapid and accurate evaluation of drinking water quality, a small-scale water quality detection instrument is designed in this paper that can detect two representative water quality parameters: the permanganate index and total dissolved solids (TDS). The permanganate index measured by the laser spectroscopy method can achieve the approximate value of the organic matter in water, and the TDS measured by the conductivity method can obtain the approximate value of the inorganic matter in water. In addition, to facilitate the popularization of civilian applications, the evaluation method of water quality based on the percent-scores proposed by us is presented in this paper. The water quality results can be displayed on the instrument screen. In the experiment, we measured the water quality parameters of the tap water as well as those after the primary and secondary filtration in Weihai City, Shandong Province, China. The testing results show that the instrument can quickly detect dissolved inorganic and organic matter, and intuitively display the water quality evaluation score on the screen. The instrument designed in this paper has the advantages of high sensitivity, high integration, and small volume, which lays the foundation for the popularity of the detection instrument. [ABSTRACT FROM AUTHOR]

Sattal Lake is one of the important lake of Nainital regions in Uttarakhand state. Physico-chemical characteristics study in the Sattal Lake has been studied. Chemical examination of the water samples collected from the sampling stations of Sattal lake were done for the tests like Total Solids (TS), pH of water, acidity of water, alkalinity of water, hardness of water, sulfate in water, Chlorides in water, Fluorides in water, Dissolved Oxygen in water, biochemical Oxygen Demand in water, chemical oxygen demand in water, total organic carbon / organic matter in water, nitrogen in water, nitrogen, ammonia, Nitrogen, nitrate, nitrogen, nitrite, nitrogen, organic and Metals in water. The study indicates that Sattal Lake is becoming a oligotrophic lake. The data have been reported in the study or present paper. [ABSTRACT FROM AUTHOR]

The paper discusses the distribution and origin of organic matter in natural waters with regard to the latitudinal geographic zoning in the European territory of Russia (ETR) and Western Siberia (WS) and demonstrates how conditions on the catchments and climate affect the content of autochthonous and allochthonous organic matter. Conditional coefficients of the ratios of these forms are calculated. The influence of the temperature factor on the content of autochthonous organic matter in the waters of the southern territories of the ETR and WS was proved by multivariate statistical methods of analysis. General trends and relations are identified in the distribution of lipids, proteins, and carbohydrates of the autochthonous and allochthonous organic compounds. The mechanism of biochemical transformation of bound carbohydrates of allochthonous organic compounds into free autochthonous ones via the microbial decomposition is demonstrated, which is more typical of waters in the southern regions of WS. The paper discusses how natural and climatic conditions can influence changes in concentrations of organic compounds in the lake waters and structural characteristics of these compounds (contents of aromatic and aliphatic fragments). [ABSTRACT FROM AUTHOR]

Unlike conventional reservoirs, shale is particularly complex in its mineral composition. As typical components in shale reservoirs, clay and organic matter have different pore structures and strong interactions with fluids, resulting in complex fluid occurrence-states in shale. For example, there are both free water and adsorbed water in clay, and both free oil and ad/absorbed oil in organic matter. Key properties such as fluid content, organic/inorganic porosity, and permeability in clay-rich shale have been poorly characterized in previous studies. In this paper, we used a vacuum-imbibition experimental method combined with nuclear magnetic resonance technique and mathematical modeling to characterize the fluid content, organic/inorganic porosity, saturation, and permeability of clay-rich shale. We conducted vacuum-imbibition experiments on both shale samples and pure clay samples to distinguish the adsorbed oil and water in clay and organic matter. The effects of clay content and total organic matter content (TOC) on porosity and adsorbed-fluid content are then discussed. Our results show that, for the tested samples, organic porosity accounts for 26–76% of total porosity. The oil content in organic matter ranges from 29% to 69% of the total oil content, and 2% to 58% of the organic oil content is ad/absorbed in kerogen. The inorganic porosity has a weak positive correlation with clay content, and organic porosity increases with rising levels of organic matter content. The organic permeability is 1–3 orders of magnitude lower than the inorganic permeability. [ABSTRACT FROM AUTHOR]

Climate change will lead to prolonged droughts in various regions of the world, which may significantly affect agricultural production. This is particularly problematic for soils with low water retention capacity, which cannot store sufficient water for crops. In this paper, we investigate how a change in the water‐holding capacity of the soil material, as could be achieved by increasing the soil organic carbon (SOC) amount, affects the components of the soil water balance (evaporation, transpiration, and groundwater recharge). Specifically, we state the hypothesis that an increased water‐holding capacity in a shallow soil layer, as it is achieved through SOC enrichment at the soil surface, will result in more water being stored near the soil surface and lost to unproductive evaporation, thereby reducing the amount of water available to plants and groundwater recharge. The hypothesis was tested by numerical simulations, employing the Hydrus‐1D program package to model the water balance in a soil–plant–atmosphere system for an arable crop in hydrologically contrasting years. The study considered soils with varying textures and different depths of a soil layer with increased SOC content. The soil hydraulic properties (SHP) of the soil material, including the effect of SOC on the SHP, were determined using a recently developed pedotransfer model based on data from over 500 samples. We showed that both the improved water retention by SOC and its vertical distribution affect the soil water balance in a complex manner. In sandy soils, increasing the water‐holding capacity in shallow layers up to 0.1 m led to enhanced evaporation and thus a decrease in water availability for crops. However, deeper incorporated SOC could ameliorate these negative effects. Our findings suggest that not only the amount but also the vertical SOC distribution should be considered if enrichment of SOC shall be applied to mitigate the effect of droughts. Core Ideas: Addition of soil organic carbon (SOC) alters soil material's hydraulic properties.This, in turn, impacts the water balance of soils under agricultural use.The depth at which SOC is incorporated into soils plays a crucial role in the partitioning of evapotranspiration (ET) into evaporation (E) and transpiration (T).Deeper incorporation of SOC results in greater water availability for plants. [ABSTRACT FROM AUTHOR]

Determining the potential sources of water that eventually become organic matter that make up the bulk of tree biomass has been facilitated by using the stable isotope composition of waters. Until recently these water sources were thought to only be taken up by roots from soils and other subsurface reservoirs. However, there is a growing body of evidence that now shows that water taken up directly by leaves and stems can not only be significant but can also dominate as the water source used in organic matter synthesis. In this commentary, I review and discuss these issues and point to an important paper by Akira Kagawa in this issue of Tree Physiology that provides a new experimental method and some striking evidence that foliar water uptake can be the primary water source that makes up tree biomass. [ABSTRACT FROM AUTHOR]

Rice cultivation under film mulching is an integrated management technology that can conserve water, increase soil temperature, improve yield, and enhance water and nitrogen use efficiencies. Despite these advantages, the system does have its drawbacks, such as soil organic matter reduction and microplastic pollution, which impede the widespread adoption of film mulching cultivation in China. Nonetheless, the advent of degradable film, controlled-release fertilizer, organic fertilizer, and film mulching machinery is promoting the development of rice film mulching cultivation. This review outlines the impact of rice cultivation under film mulching on soil moisture, soil temperature, soil fertility, greenhouse gas emissions, weed control, and disease and pest management. It also elucidates the mechanism of changes in rice growth, yield and quality, water use efficiency, and nitrogen use efficiency. This paper incorporates a review of published research articles and discusses some uncertainties and shortcomings associated with rice cultivation under film mulching. Consequently, prospective research directions for the technology of rice film mulching cultivation are outlined, and recommendations for future research into rice cultivation under film mulching are proposed. [ABSTRACT FROM AUTHOR]

As a new type of photocatalyst, molecular sieve photocatalysts have shown a promising future in the degradation of organic matter in water bodies. In this paper, a new type of molecular sieve photocatalyst was successfully prepared by introducing Bi and La elements into the hydrothermal synthesis of SAPO-34 molecular sieve for the purpose of regulating the molecular sieve backbone. The introduction of active metals into the skeleton of molecular sieve can enrich the Lewis acids acid sites on its surface. At the same time, the introduction of active metals can accelerate the transition rate of photogenerated carriers, which can also suppress the compound rate of electron holes. Under the action of 500w mercury lamp, the degradation rate of 20 ml 0.5 mg/mL formaldehyde solution was 77.61% in 6 h. Meanwhile, the degradation rate constant k could reach 0.3222 min−1, indicating that the photocatalytic degradation of formaldehyde showed excellent performance. This study provides a new method for the preparation of molecular sieve photocatalysts and a new idea for the construction of bifunctional photocatalysts. [ABSTRACT FROM AUTHOR]

Leachate is a major problem in landfills due to the type and amount of pollutants. In Croatia, the usual way of handling leachate is recirculation back to the landfill body. However, this method poses a danger of pollutant leakage into the environment, especially during periods of increased precipitation. Leachate is heavily polluted with organic matter, and its spillage into the environment can cause environmental incidents. This paper presents a model for the efficient treatment of landfill water contaminated with organic matter based on the operating parameters of the existing water treatment system. This scientific research aims to develop a model for landfill water treatment and to design a methodology suitable for significant patterns of organic matter pollution behaviour. The developed conceptual model is a computer-based model that uses randomly selected values from the theoretical probability distribution of the applied variables. The mathematical model is based on a system of differential equations solved by the Runge-Kutta method. A non-parametric test was applied to validate the model, given that the distributions are asymmetric non-Gaussian. The methodology proposed in this paper is based on simulation modelling as a useful method in environmental protection. The developed and validated model has proven that landfill water can be effectively and economically purified. Simulation modelling and environmental informatics can effectively contribute to solving environmental problems on the computer without unnecessary environmental risk. [ABSTRACT FROM AUTHOR]

The coal pillar dam of underground reservoirs and residual coal in goaves have a direct impact on the quality of mine water. In this paper, the coal pillar dam of an underground reservoir and residual coal in the goaf and mine water in the Daliuta coal mine are used as research objects. The adsorption mechanism of residual coal with respect to NO 3 − in mine water was analyzed by carrying out adsorption experiments. The composition and variation of organic matter in mine water at different times were simulated using three-dimensional fluorescence spectrum analysis. The influence of residual coal and microorganisms in underground reservoirs on the change in NO 3 − contents in mine water was explored. Moreover, the mechanism of NO 3 − changes in the water body was clarified. The results showed that the concentration of NO 3 − in the water first decreased and then increased, showing a downward trend as a whole. The adsorption of NO 3 − by residual coal led to a decrease in its concentration, which conformed to a pseudo-second-order kinetic model and Freundlich isothermal adsorption model, indicating that the adsorption process of NO 3 − by residual coal is mainly carried out via chemical adsorption and multi-layer adsorption. The increase in NO 3 − concentration was caused by the hydrolysis of tryptophan and other protein-like substances in the water into nitrate under the action of microorganisms. [ABSTRACT FROM AUTHOR]

The lidar ratio of seawater is an essential quantity related to both lidar retrieval and water constituent. However, few studies discuss its spatial–temporal characteristics and ecological significance, which limits its applications in lidar remote sensing and marine science. This paper investigates the spatial–temporal characteristics and ecological significance of the lidar ratio of seawater using satellite passive remote sensing, which is validated by in situ measurements. Spatially, nearshore lidar ratio values are higher than offshore, mainly owing to the high concentration of colored dissolved organic matter in nearshore water. Temporally, the lidar ratio in each hemisphere exhibits lower values in summer than in winter due to the annual boom–bust cycle of phytoplankton. Furthermore, the variability patterns of the lidar ratio are nearly consistent with those of the chlorophyll-to-carbon ratio, implying the high ecological significance of phytoplankton physiology. These findings will provide the foundation for the application of lidar ratio in marine science and lidar remote sensing. [ABSTRACT FROM AUTHOR]

Chemical oxygen demand (COD) is an important indicator for monitoring the quality of seawater. The COD of seawater reflects the levels of organic pollutants in the water. Methods that are commonly used to measure the COD of seawater have high accuracy, good repeatability, and low costs. However, using them for the in situ real-time monitoring of the COD of seawater is unfavorable because they require complex procedures and a long measurement time and may cause pollution to the environment. This paper reports on an optical sensor that accurately determines the COD of seawater in situ. The COD determination is based on the absorption of ultraviolet and visible lights with different wavelengths by organic matter in the water. Single-point LEDs emitting lights with different wavelengths (254, 265, 280, and 546 nm) were used as sources of excitation lights, and photodiodes were used as receiving devices. The optical system, circuit system, and mechanical structure of the sensor were efficiently integrated. The inversion of the COD of seawater was obtained after turbidity correction using the multiple linear regression algorithm. The maximum measurement error, detection limit, and repeatability of the sensor were 5%, 0.05 mg/l, and 0.62%, respectively. Moreover, the R2 values for correlations between COD values and absorbance values measured at three wavelengths (254, 265, and 280 nm) were above 0.99. Overall, the sensor is suitable for the in situ real-time monitoring of the COD of seawater. It requires a short measurement time and generates no pollution. [ABSTRACT FROM AUTHOR]

The structure of soil is critical for the ecosystem services it provides since it regulates many key soil processes, including water, air and solute movement, root growth and the activity of soil biota. Soil structure is dynamic, driven by external factors such as land management and climate and mediated by a wide range of biological agents and physical processes operating at strongly contrasting time‐scales, from seconds (e.g., tillage) to many decades (e.g., faunal activity and soil aggregation). In this respect, positive feedbacks in the soil–plant system may lead in the longer term to soil physical degradation or to the recovery of structurally poor soils. As far as we are aware, no existing soil‐crop model can account for such processes. In this paper, we describe a new soil‐crop model (USSF, Uppsala model of Soil Structure and Function) that accounts for the effects of soil structure dynamics on water and organic matter cycling at the soil profile scale. Soil structure dynamics are expressed as time‐varying physical (bulk density, porosity) and hydraulic properties (water retention, hydraulic conductivity) responding to the activity of biological agents (i.e., earthworms, plant roots) and physical processes (i.e., tillage, soil swell‐shrink) at seasonal to decadal time‐scales. In this first application of the model, we present the results of 30‐year scenario simulations that illustrate the potential role and importance of soil structure dynamics for the soil water balance, carbon storage in soil, root growth, and winter wheat yields on two soils (loam and clay) in the climate of central Sweden. A sensitivity analysis was also performed for these two scenarios using the Morris method of elementary effects, which revealed that the most sensitive parameters controlling soil structure dynamics in the USSF model are those determining aggregation induced by organic matter turnover and swell/shrink. We suggest that the USSF model is a promising new tool to investigate a wide range of processes and phenomena triggered by land use and climate change. Results from this study show that feedback in the soil‐crop system mediated by the dynamics of soil physical and hydraulic properties are potentially of central importance for long‐term predictions of soil water balance, crop production, and carbon sequestration under global change. [ABSTRACT FROM AUTHOR]

Previous studies have often observed that moisture can promote the lubricity and wear resistance of carbon-metal contact pairs in purely mechanical conditions. However, the damage to pantograph carbon strips was found to be aggravated in rainfall conditions, leading to a much lower service life than anticipated. This suggests a novel influence mechanism of water on carbon-copper (C-Cu) contacts during current-carrying friction. In this paper, the influence mechanism of water on the current-carrying friction characteristics of carbon-copper contacts, including friction coefficient, wear loss, electrical contact resistance, and arc discharge characteristics, was studied under different current levels by controlling the water content of carbon sliders. The results show that the variation trend of current-carrying tribological parameters of C-Cu contacts with water content at 60–100 A is significantly different from that at 20–40 A, which is mainly the result of the competition of lubrication, cooling, and obstruction of current transmission by moisture. The abnormal wear of carbon sliders in the water environment occurs when the current is greater than 60 A, and the main reason for the abnormal wear is the intensification of discharge erosion. In addition, micro-crack propagation under high water content is an important factor in the deterioration of carbon strip properties. [ABSTRACT FROM AUTHOR]

The unique structure and properties of graphene make it have excellent performance in the field of catalysis. It can be modified in various ways to improve its catalytic ability. Notably, other 2D materials with similar properties to graphene (black phosphorus (BP), 2D transition metal dichalcogenides represented by molybdenum disulfide (MoS2) and tungsten disulfide (WS2), boron nitride (BN), and transition metal carbide and nitride (MXenes) and their hybrid materials also have a wide range of applications in the field of catalysis. In general, 2D materials can be used as catalysts, catalytic supports or electron donors. Therefore, they have been widely used in many catalytic reactions in recent years, such as photocatalysis, thermocatalysis, and electrocatalysis. In this paper, the research progress of the above 2D materials in the catalytic degradation of organic matter in water and carbon dioxide reduction reaction (CO2RR) is summarized. In addition, some excellent composite 2D catalysts in the fields of photocatalysis and electrocatalysis are summarized and compared. Finally, the opportunities and challenges of the above 2D materials in the field of catalysis are pointed out, and the development prospects of the 2D materials in the field of catalysis are addressed. [ABSTRACT FROM AUTHOR]

As the largest contiguous karst area in China, the southwestern karst area is a typical ecologically fragile area affecting local vegetation dynamics. Ecosystem water use efficiency (WUE) is an important factor reflecting the ability of vegetation to produce organic matter with a limited water supply. Therefore, determining the WUE variation trends in this ecologically fragile region is important. In this paper, we used MODIS remote sensing datasets, meteorological data, and land cover data to analyze the spatiotemporal changes in vegetation water use efficiency in the southwestern karst region from 2001 to 2017. We also further quantitatively analyzed the effects of climate change and human activities on the spatial and temporal patterns of vegetation WUE in the study area. The main conclusions were as follows. (1) From 2001 to 2017, in terms of temporal characteristics, the interannual variation in WUE fluctuated greatly, ranging from 1.33 to 1.51 g C kg−1 H2O, with a multiyear average of 1.43 g C kg−1 H2O and an average rate of change of − 0.0046 g C kg−1 H2O year−1. In terms of spatial characteristics, areas with a higher WUE were concentrated in central Sichuan and northeastern Yunnan. (2) The annual average WUE of each vegetation type decreased in the following order: evergreen coniferous forest > evergreen broad-leaved forest > mixed forest > deciduous broad-leaved forest > cultivated land > deciduous coniferous forest > grassland > cultivated land and natural vegetation > shrub forest. (3) The vegetation WUE of 70.66% in this area was positively correlated with temperature. Additionally, 79.68% of the vegetation WUE was negatively correlated with precipitation. The relative contribution rates of climate change and human activities to the change trend in WUE were 15% and 85%, respectively. Compared with WUE results in other studies, the WUE of different karst landform areas obtained in this study was quite different, indicating that the geological and landform features of the karst area are complex. Our study provides scientific support for local vegetation restoration and protection policies and promotes the understanding of the principle of the carbon–water cycle in karst areas. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents results of a long-term (1990–2018) study of changes in the geochemistry of land waters in the Kola region as a consequence of climate warming and a regional- and global-scale decrease in the emission of acid-forming gases. The work is based on materials acquired by studying 75 small lakes in the region every four to five years in the period of time of 1990 through 2018. Reliable trends toward a temperature rise over a 28-year study period were revealed based on the analysis of weather archives. It was found out that the content of anthropogenic sulfates in the water significantly decreased and the acid-neutralizing capacity of waters increased due to the reduction in the anthropogenic sulfur emissions into the atmosphere. An increase in the content of organic matter and nutrients in the water of lakes has been proven, which is reliably associated with an increase in the regional temperatures. A number of lakes in acid-vulnerable regions retain critical values of the acid-neutralizing capacity of waters, which may be associated with both local and transregional transport of polluted air masses. The analysis of the chemical variability the waters in a long-term series of observations demonstrates the evolutionary development of lakes and changes in the biogeochemical cycles as a consequence of the transformation of the watersheds under the influence of a decrease in acid deposition from the atmosphere on the catchment areas and climate warming in the region. [ABSTRACT FROM AUTHOR]

Climate change and human activities have been heavily affecting oceanic and inland waters, and it is critical to have a comprehensive understanding of the aquatic optical properties of lakes. Since many key watercolor parameters of Qinghai Lake are not yet available, this paper aims to study the spatial and temporal variations of the water clarity (i.e., Secchi-disk depth, Z SD ) and suspended particulate matter concentration ( C SPM ) in Qinghai Lake from 2001 to 2020 using MODIS images. First, the four atmospheric correction models, including the NIR–SWIR, MUMM, POLYMER, and C2RCC were tested. The NIR–SWIR with decent accuracy in all bands was chosen for the experiment. Then, four existing models for Z SD and six models for C SPM were evaluated. Two semi-analytical models proposed by Lee (2015) and Jiang (2021) were selected for Z SD ( R 2 = 0.74) and C SPM ( R 2 = 0.73), respectively. Finally, the distribution and variation of the Z SD and C SPM were derived over the past 20 years. Overall, the water of Qinghai Lake is quite clear: the monthly mean Z SD is 5.34 ± 1.33 m, and C SPM is 2.05 ± 1.22 mg/L. Further analytical results reveal that the Z SD and C SPM are highly correlated, and the relationship can be formulated with Z SD = 8.072 e − 0.212 C SPM ( R 2 = 0.65). Moreover, turbid water mainly exists along the edge of Qinghai Lake, especially on the northwestern and northeastern shores. The variation in the lakeshore exhibits some irregularity, while the main area of the lake experiences mild water quality deterioration. Statistically, 81.67% of the total area is dominated by constantly increased C SPM , and the area with decreased C SPM occupies 4.56%. There has been distinct seasonal water quality deterioration in the non-frozen period (from May to October). The water quality broadly deteriorated from 2001 to 2008. The year 2008 witnessed a sudden distinct improvement, and after that, the water quality experienced an extremely inconspicuous degradation. This study can fill the gap regarding the long-time monitoring of water clarity and total suspended matter in Qinghai Lake and is expected to provide a scientific reference for the protection and management of the lake. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Sciences is the property of Faculty of Engineering - Assiut University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Marine free‐living (FL) bacteria play a key role in the cycling of essential biogeochemical elements, including iron (Fe), during their uptake, transformation and release of organic matter throughout the water column. Similar to phytoplankton, the growth of FL bacteria is regulated by nutritive resources such as Fe, and the low availability of these resources may influence bacterial interactions with phytoplankton, causing knock‐on effects for biogeochemical cycling. Yet, knowledge of the factors limiting the growth of FL bacteria and their role within the Fe cycle is poorly constrained. Here, we explicitly represent FL, carbon‐oxidizing bacteria in a three‐dimensional global ocean biogeochemistry model to address these questions. We find that although Fe can emerge as proximally limiting in the tropical Pacific and in high‐latitude regions during summer, the growth of FL bacteria is ultimately controlled by the availability of labile dissolved organic carbon over most of the world's oceans. In Fe‐limited regions, FL bacterial biomass is sensitive to their Fe uptake capability in seasonally Fe‐limitation regions and to their minimum Fe requirements in regions perennially low in Fe. Fe consumption by FL bacteria is significant in the upper ocean in our model, and their competition with phytoplankton for Fe affects phytoplankton growth dynamics and can make bacteria become more carbon limited. The impact of FL bacteria on the Fe distribution in the ocean interior is small due to a tight coupling between Fe uptake and release. Moving forward, future work that considers other bacteria groups and different bacterial metabolisms is needed to explore the broader role of bacteria in ocean Fe cycling. In this context, the global growing' omics data from ocean observing programs can play a crucial role. Plain Language Summary: Marine heterotrophic bacteria, a ubiquitous group of microorganisms, can control the cycling of essential biogeochemical elements in the ocean, including the micronutrient iron. However, factors limiting the growth of bacteria and the impact of bacteria on ocean iron distributions are still poorly understood. In this paper, we represent the free‐living (FL) bacteria in an ocean biogeochemistry model to show that the availability of labile dissolved organic carbon is the ultimate limiting factor for the growth of FL bacteria, while iron can be a co‐limiting factor in iron‐limited regions. We also suggest that the competition between phytoplankton and FL bacteria for iron can significantly alter both phytoplankton blooms and bacterial growth. Future studies should exploit new genomics information to further explore the roles of other bacteria groups. Key Points: Iron emerges as a proximal limiting factor for the growth of free‐living (FL) bacteria in low iron regions, with dissolved organic carbon being the ultimate limiting resourceWhile FL bacteria consume a significant amount of iron in the surface ocean and affect phytoplankton dynamics, their impact on the subsurface iron cycling is smallA more complete understanding of the role of bacteria requires holistic consideration of the role of different bacterial groups and their specific iron requirements via expanded observations of these key groups [ABSTRACT FROM AUTHOR]

Together with the development of measurement techniques, radiocarbon (14C) has been increasingly used as a key tool to investigate carbon cycling and associated biogeochemistry in the ocean. In this paper, the current status of radiocarbon studies in the East Sea (Japan Sea) is reviewed. Previously, spatiotemporal distribution and change of the water masses in the East Sea from 1979 to 1999 were investigated by using the 14C in the dissolved inorganic carbon (DIC). Researches on sinking particulate organic carbon (POC) revealed that POC in the deep ocean has more complex and heterogeneous origins than we expected. In particular, since 2011, Korean researchers have been collecting sinking particle samples for more than 10 years, so it is expected that 14C of POC will provide important information to understand carbon cycling in relation to climate change. Although the quantity of 14C data published in the East Sea is still limited, the importance and the future direction of using 14C to understand the biogeochemical mechanisms of carbon cycling and its role as a carbon reservoir in the East Sea are detailed herein. [ABSTRACT FROM AUTHOR]

The main objective of wastewater treatment is to purify the water by degradation of organic matter in the water to an environmentally friendly status. To achieve this objective, some effluent (waste water) quality parameters such as Chemical oxygen demand (COD) and Biochemical oxygen demand (BOD5) should be measured continuously in order to meet up with the said objective and regulatory demands. However, through the prediction on water quality parameters, effective guidance can be provided to comply with such demand without necessarily engaging in rigorous laboratory analysis. Box-Jenkin’s Auto Regressive Integrated Moving Average (ARIMA) technique is one of the most refined extrapolation techniques for prediction while Artificial Neural Network (ANN) is a modern non-linear method also used for prediction. The Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), Root Mean Square Error (RMSE) and Correlation coefficient (r) are used to evaluate the accuracy of the above-mentioned models. This paper examined the efficiency of ARIMA and ANN models in prediction of two major water quality parameters (COD and BOD5) in a wastewater treatment plant. With the aid of R software, it was concluded that in all the error estimates, ANNs models performed better than the ARIMA model, hence it can be used in the operation of the treatment system. [ABSTRACT FROM AUTHOR]

Despite the abundance of renewable resources, renewable energy accounts for less than 1% of the total installed power capacity in oil‐producing Gulf Arab states. While the political–economic structures of oil‐producing Gulf Arab states are thought to have played a role in determining these states' remarkably low uptake of renewable energy, these structures remain understudied. With a focus on Oman, we assess how political–economic structures have influenced its adoption of renewable energy. We implement an analytical framework that integrates insights from energy transition studies and the political–economic theory of rentier states. Drawing on secondary data and primary information from semi‐structured interviews with renewable energy developers and energy experts, this study reveals that renewable energy roll‐out in Oman has been delayed through three different strategies, namely the use media and public debate, a reduction of the power of renewable energy stakeholders, and the use of institutional mechanisms to strengthen hydrocarbon‐based technologies. Oman's renewable energy transition efforts aim to protect rents from oil exports rather than advance low‐carbon energy transition. [ABSTRACT FROM AUTHOR]

Efficient removal of dissolved organic matter (DOM) is an important task for wastewater treatment. However, the molecular composition of DOM and its transformation during the treatment are still unclear. In this paper, the organic components in the stream of a coal coking wastewater treatment process were studied. The wastewater was extracted by dichloromethane (CH2Cl2)，the extract was named as ‘oil phase’. Then the raffinate was extracted by solid-phase extraction, the extract was named as ‘water phase’. The ratios of total organic carbon contents (TOC) in the oil and water phase samples were generally consistent during the treatment process. The extracted DOM was characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Eight class species were as assigned from the mass spectra, namely N1O1-7, N2O1-6, N1O5, N1O2-6S1, N2O3-5S1, O2-8, O2-6S1, O4-5S2. The class categories which contain multiple oxygen atoms (Ox) and both multiple oxygen and sulfur atoms (OxSy) were dominant in the oil phase. The relative abundance of each species was decreased sharply after the first aerobic biological process, which was consistent with the TOC rapid decline in the sample. O2-8 compounds existed in all wastewater samples and dominated in the final sample, indicating that these compounds were the most stubborn pollutants which were difficult to remove in all treatment processes. It is speculated that these compounds may come from some humic-acids which have complex structure and multiple oxygen atoms naturally existing in natural water. The composition of O3 class species showed two patterns among the wastewater treatment process, compounds with high double bond equivalent (DBE) were dominant in the first four processes, while a proliferation of low DBE components was observed in the last three samples. It indicated that those low DBE components were generated by the oxidation of other substances, such as O1 and O2 species. The water phase organic matter had an extremely complex molecular composition and a total of 27 different compound class species were identified in a single mass spectrum. Ox, OxS1-2 and  NxOyS1-2 were the major class categories in water phase. On the whole, OxS1-2 was much easier than the other two categories to be removed during the wastewater treatment process. In the OxS1-2 class category, O4S1 had a much higher relative abundance than other species. It decreased sharply among the process, but it still accounted for a large proportion in the final process, which implied the O4S1 species had strong resistance to removal. The relative abundances of each species in NxOyS1-2 had consistent composition and transformation, and could be effectively removed after the wastewater treatment process. The composition transformation trend of O6S1 was similar to N1O6S1, those compounds with low DBE value (512) and low carbon number (1020) were dominated after the aerobic biological process section and remained in the final process. The study of DOM in coal coking wastewater treatment from the molecular level by FT-ICR MS will contribute to understand the transformation law of pollutant compounds. However, limited by the mass spectrometry, only the molecular composition information can be obtained. The molecular structure information, especially for the functional groups, is hard to be obtained. In order to research the transformations law of pollutant compounds for further, the structural information needs to be deduced combining the molecular composition, the precursor and the polarity of wastewater pollutants. Developing more efficient and advanced separation and enrichment methods is another way to research the molecular structure information. By the further work, a fully understand of the pollutant composition will be obtained, and a more effective wastewater treatment process will be developed. [ABSTRACT FROM AUTHOR]

This paper presents recently obtained palebotanical data regarding the evolution of Lake Paleolotos in the Middle Pleistocene. Its evolution was more complicated than the development of the adjacent lakes in the coast of Peter the Great Bay (the Sea of Japan). The Middle Pleistocene lacustrine sediments accumulated in the downstream of the Tumannaya River (the most southwestern area of Primorye, Russia Far East) were studied using diatom and pollen analytical methods. We found that the Lake Paleolotos arose during Marine Isotope Stage 11 (MIS 11) and disappeared during MIS 6. For more than half of its existence (MIS 11–8), it was a freshwater oligotrophic basin with a depth of at least 20 m, with clear waters and poor organic matter content. The lake occupied most of the modern accumulative plain on the left bank of the Tumannaya River, reaching a size of at least 10–12 km across. During MIS 7–6 Lake Paleolotos turned into a shallow-water basin (its depth most likely did not exceed 1–3 m) of a eutrophic type with turbid waters rich in organic matter. Palynological data suggest that during MIS 11, 9 and 7 the area adjacent to the Lake was covered with coniferous/broad-leaved forests with presence of some thermophilic plants of North China and North Korea Flora (Castanea , Celtis , Magnolia , Tsuga and Cupressaceae). This indicates that vegetation zones were displaced by about 500–700 km to the north relative to their present position. During periods of cooling they were replaced by coniferous/small-leaved forests with the participation of shrub species of birch and alder (MIS 10) and coniferous/small-leaved forests consisted of pine, birch, and spruce with the participation of elm and oak (MIS 8 and 6). [ABSTRACT FROM AUTHOR]

Rivers are pivotal in the global carbon cycle, transporting terrestrial carbon to the ocean while emitting significant amount of CO2 ${\mathrm{C}\mathrm{O}}_{2}$ to the atmosphere. However, the partitioning of fluvial inorganic carbon (IC) between downstream transport and atmospheric evasion remains uncertain due to intricate hydrodynamic and biogeochemical processes. Inspired by Budyko's hydrological work, this study introduces a dimensionless framework to identify critical factors in fluvial IC partitioning: the IC fraction in equilibrium with the atmosphere and the ratio of advection to evasion timescales. River catchment analyses and modeling reveal that the equilibrium ratio determines the fraction of IC stably transported downstream. The hydrodynamic‐driven timescale ratio determines the fate of out‐of‐equilibrium IC, with low‐order streams favoring atmospheric evasion and higher‐order streams promoting downstream transport. This framework provides a simple yet robust approach to predicting river carbon dynamics, with implications for land‐to‐ocean transport, fluvial emissions, and climate mitigation strategies such as enhanced weathering. Plain Language Summary: Rivers contain large amounts of dissolved inorganic carbon originating from the decomposition of organic matter and soil water fluxes. This carbon is partly transported downstream across the river network to the ocean and partly emitted as CO2 ${\mathrm{C}\mathrm{O}}_{2}$ to the atmosphere. Quantifying the partitioning between these fluxes is crucial for accurate carbon budgets from the local to the global scale, but the complex interplay of biogeophysical processes makes it challenging. Inspired by Budyko's seminal work in hydrology, we present a framework that determines the main chemical and physical processes governing the fluvial inorganic carbon partitioning. We identify two dimensionless numbers (or indexes) that can be defined with only a few parameters and provide quantitative and robust predictions on fluvial carbon fate. These numbers are linked to water turbulence and chemistry, and their values change across the river network. Key Points: Rivers partition inorganic carbon between downstream transport and CO2 ${\mathrm{C}\mathrm{O}}_{2}$ emissions to the atmosphereIncorporating key hydrodynamic and biogeochemical processes, we identify the dimensionless numbers that govern the inorganic carbon partitioningWater hydrodynamics plays a critical role in the fate of the carbon that is out of equilibrium with the atmosphere [ABSTRACT FROM AUTHOR]

The ocean industries are characterized by being export-driven. The exports of ocean industries (hereafter termed ocean exports) caused environmental pollution with amounts of CO2 emissions and thereby affected climate change. There is a need, therefore, for accurate assessments of CO2 emissions embodied in ocean exports--which can help policymakers adopt targeted emissionreduction measures to formulate sustainable ocean policies. However, few studies of ocean-industry emissions considered impacts in sectoral and trade pattern heterogeneity, especially from export perspective. To fill this gap, we measured and evaluated the export-embodied CO2 emissions from China's ocean industries, based on our newly developed high-resolution and comparable time-series environmentally extended input-output database, called EE-DPN-OEIOT. The results showed that China's ocean exports generated 94.3 Mt of embodied CO2 emissions in 2017, with nearly 40% originating from processing ocean exports. Regarding the evolution from 2007 to 2017, the total export-embodied CO2 emissions from ocean industries decreased by 7.3%, while the embodied CO2 emissions in processing ocean exports increased by 50.1%. From 2007 to 2017, the decrease in carbon emission intensity was the major driving factor of the downturn in export-embodied CO2 emissions across the total ocean economy and for seven ocean subsectors (60%), while the export-scale effect primarily drove the increases in CO2 emissions. Moreover, there were disparities in the driving factors behind changes in embodied CO2 emissions between processing and non-processing ocean exports. Based on our findings, we proposed three recommendations from a trade perspective to facilitate low-carbon sustainable transition of China's ocean economy, thus better fulfilling Sustainable Development Goal 14. [ABSTRACT FROM AUTHOR]

Background: Dissolved organic matter (DOM) plays a significant role in the biogeochemical cycle of crucial elements in aquatic ecosystem. However, it is still not clear on the spectral characteristics of water DOM in different types of alpine wetlands, which have less anthropogenic influences and intensive ultraviolet radiation. Here, we collected 107 water samples from marsh, lake, and river wetlands in the Zoige plateau, China, and analyzed the chemical characteristics, compositions, and potential sources of chromophoric DOM by combining UV–vis spectroscopy and excitation–emission matrix fluorescence spectroscopy coupled with parallel factor analysis (EEMs-PARAFAC). Results: UVC and UVA fulvic-like substances were the prevailing fluorescence components in water DOM, which accounted for 23.74–71.59% and 16.76–30.01% of the total fluorescence intensity, respectively. Compared with the lake and river wetlands, fluoresce intensities of UVC and UVA fulvic-like substances in DOM were higher in marsh wetland. Marsh wetlands possessed the highest SUVA254, E2/E3, E2/E4, and E4/E6 of DOM, suggesting higher humification degree, higher relative molecular nominal size, and higher aromaticity. And the E2/E4 ratios in most water samples were higher than 12, indicating water DOM was mainly derived from autochthonous sources in alpine wetlands. Conclusions: Wetland types strongly affected the spectral characteristics of water DOM in Zoige plateau. These findings may be beneficial for sustainable management of alpine wetlands. [ABSTRACT FROM AUTHOR]

Activated carbon fiber, also known as the third generation of activated carbon material, is a new type of activated carbon material after powder and granules, made of the organic fiber. Activated carbon fiber has a strong adsorption capacity due to its large specific surface area, and can adsorb and remove organic matter in water, including some carcinogenic or toxic macro-aromatic substances. Physical adsorption is caused by electrostatic interaction between the surface molecules of the adsorbent and the adsorbate molecules, which is characterized by adsorption without selectivity. Chemical adsorption is due to the chemical bonding between the two molecules, forming a strong chemical bond and also the surface complex. Chemical adsorption has the certain selectivity, generally monolayer adsorption. With the large increase in vehicle usage and the exhaust emissions from equipment such as oil-fired boilers, the pollution of nitrogen oxides and carbon monoxide gas has become an important issue in environmental management. Adsorption or catalytic conversion of nitrogen oxides and carbon monoxide is an important means of treatment. This paper integrates the smart city scenario to construct the novel scenario for the analysis and research. The simulation results prove the effectiveness. [ABSTRACT FROM AUTHOR]

Emerging technologies like enhanced oil recovery and carbon sequestration rely on carbon dioxide water content data to ensure that pipelines remain sub-saturated to avoid corrosion and hydrate flow assurance issues. To improve throughput and confidence in the hydrate phase equilibria data to avoid pipeline blockages, further research into the carbon dioxide water content must be conducted. However, the liquid carbon dioxide regime is experimentally difficult to study and the available data disagree between studies. This work aims to provide the critical and accurate data for liquid carbon dioxide for a high pressure range (13.8 to 103.4 bar) and temperature range (20 and −30 °C) utilizing a small volume microfluidic reactor (<20 microliter) coupled with Raman spectroscopy, which can reveal any phase metastability in the system. The small volume of the microfluidic system (<20 microliter) allowed experiments to be run in a few hours, compared to a whole week for prior larger scale measurements. The carbon dioxide water content results from this work agree well with both model predictions and available literature data in the gas region; however, once carbon dioxide was converted to liquid, the data showed a weak function of pressure, similar to model predictions and some previous data sets. The discrepancies between literature data are attributed to metastable phases present in the equilibrium cells, as the data is usually taken in the carbon dioxide near critical region, close to carbon dioxide's dew point, and near the hydrate phase transition. For these reasons, it is important to observe and qualify all phases in the cell, as was done in this novel study with in situ Raman spectroscopy coupled to Midstream on a chip, to ensure accurate water content of the carbon dioxide fluid phase is being measured. [ABSTRACT FROM AUTHOR]

The application of low-pressure nanofiltration (NF) was investigated for three different applications: water reuse from acid mine drainage (AMD), surface water containing natural organic matter (NOM) and agricultural reuse of microfiltered biologically treated sewage effluent (MF-BTSE). AMD contains many valuable rare earth elements (REEs) and copper (Cu) that can be recovered with fresh water. The NF90 membrane was investigated for recovery of fresh water from synthetic AMD. A steady permeate flux of 15.5 ± 0.2 L/m2h was achieved for pretreated AMD with over 98% solute rejection. NF90 achieved a high dissolved organic carbon (DOC) rejection of 95% from surface water containing NOM where 80% of the organic fraction was hydrophilic, mainly humics. The NF process maintained a high permeate flux of 52 LMH at 4 bars. The MF-BTSE was treated by NTR-729HF for agricultural reuse. NTR-729HF membranes were capable of rejecting DOC and inorganics such as sulfates and divalent ions (SO42−, Ca2+ and Mg2+) from MF-BTSE, with less than 20% rejection of monovalent (Na+ and Cl−) ions. The sodium adsorption ratio (SAR) was significantly reduced from 39 to 14 after treatment through NTR-729HF at 4 bar. The resulting water was found to be suitable to irrigate salt-sensitive crops. [ABSTRACT FROM AUTHOR]

This article is about the diversity of diatoms in the benthos of the upper sublittoral near Kazantip Cape, located on the shore of the Sea of Azov in the northeastern part of Crimea. The study was conducted in 2022 and 2023 at a depth of 0.1 to 1 m at temperatures from 3.7 °C to 29 °C and salinity from 13.6 to 15.6 psu on the following 11 species of macroalgae: Phaeophyta of Ericaria crinita, Gongolaria barbata, and Cladosiphon mediterraneus; Chlorophyta—Bryopsis hypnoides, Cladophora liniformis, Ulva intestinalis, and Ulva linza; and Rhodophyta—Callithamnion corymbosum, Ceramium arborescens, Polysiphonia denudata, and Pyropia leucosticta. A total of 97 taxa of Bacillariophyta belonging to 3 classes, 21 orders, 30 families, and 45 genera were found. The highest number of diatom species was found on U. linza (61 species), P. denudata (45), E. crinita (40), the lowest number was recorded on thalli P. leucosticta (9). On macroalgae were found of 80% benthic diatoms, 50% marine species, 36% brackish-marine, 9% freshwater, 5% brackish, and 36% cosmopolites. The maximum abundance of the diatom community was 243.4 × 103 cells/cm2 (P. denudata in September at 23.9 °C and 15.0 psu) with dominance by the diatom of Licmophora abbreviata, and the minimum was 3.8 × 103 cells/cm2 (P. leucosticta in January at 3.7 °C and 15.0 psu). The presence in the epiphyton of diatoms—indicators of moderate organic water pollution (32 species), which developed in masse in late summer—indicate a constant inflow of organic matter into the coastal waters of the Kazantip Cape. The bioindicator and statistical studies indicate the effectiveness of the conservation regime, especially at stations within the IUCN reserve, despite relatively high saprobity rates at stations exposed to recreational pressure and poorly treated domestic wastewater. [ABSTRACT FROM AUTHOR]

With the gradual depletion of conventional petroleum resources, oil shale, as an important unconventional oil and gas resource, is of great significance to alleviate the global energy crisis and optimize the energy structure. In this study, we comprehensively assessed the organic matter abundance, type, maturity, and trace element characteristics of oil shale by collecting and analyzing oil shale samples from the Lower Permian region in the western part of the southern margin of the Junggar Basin, and by applying pyrolysis analysis and rock pyrolysis analysis. The study showed that the average value of total organic carbon (TOC) of the oil shale in the study area was 10.26%, of which 41.67% was medium-grade oil shale and 58.33% was low-grade oil shale, reflecting the overall abundance of medium-low organic matter. The average value of hydrocarbon potential was 40.83 mg/g. The hydrogen index of the oil shale samples ranged from 77 to 861.06 mg/g, with an average value of 405.56 mg/g. The organic matter type was mainly of the II1 type (humic-sapropelic type), which accounted for 75% of the total, and the analysis of the highest pyrolysis peak temperature showed that 83.33% of the samples were in the low maturity-mature stage. Trace element analyses revealed that the oil shales in the study area were formed in a terrestrialweakly reduced depositional environment. Especially, the analysis of Sr/Ba, Th/U and B/Ga ratios indicated that the oil shale was mainly formed in freshwater-semi-saline environment. In addition, the analysis of V/(V+Ni) and U/Th ratios supports the reduced environment in which the oil shale was formed. The shale in the Dalongkou area has greater salinity values and higher organic matter productivity in the water body at the time of formation compared to the oil shale in the Cangfanggou area. The results of this study are important for understanding the geochemical properties and mineralization potential of the Lower Permian oil shales in the western part of the southern margin of the Junggar Basin. [ABSTRACT FROM AUTHOR]

This study investigates the environmental impacts caused by the scaling up of the photocatalytic purification of drinking water using ultraviolet light-emitting diode technology. The life cycle assessment methodology was utilised to estimate the environmental impacts of two different reactor setups commonly used in lab-scale studies: an immobilised and a suspended TiO2 catalytic system. The functional unit adopted was the treatment of 1 L of water with an initial 7.8 mg/L concentration of natural organic matter, achieving a final 1 mg/L concentration. The use of a suspended photocatalyst was found to have an environmental footprint that was 87% lower than that of the immobilised one. From the sensitivity analysis, the environmental hotspots of the treatment process were the electricity usage and immobilised catalyst production. Therefore, alternative scenarios investigating the use of a renewable electricity mix and recyclable materials were explored to enhance the environmental performance of the photocatalytic treatment process. Using a renewable electricity mix, a decrease of 55% and 15% for the suspended and immobilised catalyst, respectively, was observed. Additionally, the process of recycling the glass used to support the immobilised catalyst achieved a maximum reduction of 22% in the environmental impact from the original scenario, with 100 glass reuses appearing to provide diminishing returns on the environmental impact savings. [ABSTRACT FROM AUTHOR]

The composition of dissolved organic matter of cloud water has been investigated through non-targeted high-resolution mass spectrometry on only a few samples that were mostly collected in the Northern Hemisphere in the USA, Europe and China. There remains, therefore, a lack of measurements for clouds located in the Southern Hemisphere, under tropical conditions and influenced by forest emissions. As a matter of fact, the comparison of the composition of clouds collected in different locations is challenging since the methodology for the analysis and data treatment is not standardized. In this work, the chemical composition of three samples collected at Réunion Island (REU) during the BIO-MAÏDO field campaign, in the Indian Ocean, with influences from marine, anthropogenic and biogenic (tropical) emissions, is investigated and compared to the chemical composition of samples collected at the Puy de Dôme (PUY) observatory in France. The same methodology of analysis and data treatment was employed, producing a unique dataset for the investigation of the molecular composition of organic matter in cloud water. Besides the analysis of elemental composition, we investigated the carbon oxidation state (OSC) of dissolved organic matter, finding that overall samples collected at PUY are more oxidized than those collected at REU. Molecular formulas were also classified based on stoichiometric elemental ratios, showing the high frequency and abundance of reduced organic compounds, classified as lipids (LipidC), in this matrix, which led to a search for terpene oxidation products in cloud water samples. To better discriminate between samples collected at PUY and REU, statistical analysis (principal component analysis and agglomerative hierarchical clustering) was performed on the ensemble of molecular formulas and their intensities. Samples collected at REU have a different composition from samples collected at PUY, which is mainly linked to different primary sources, the processing of organic matter in cloud water and the influence of different primary emissions at the two locations. [ABSTRACT FROM AUTHOR]

Size exclusion chromatography with total organic carbon detection (HPSEC-TOC) is a widely employed technique for characterizing aquatic natural organic matter (NOM) into high, medium, and low molecular weight fractions. This study validates the suitability of HPSEC-TOC for a simplified yet efficient routine analysis of freshwater and its application within drinking water treatment plants. The investigation highlights key procedural considerations for optimal results and shows the importance of sample preservation by refrigeration with a maximum storage duration of two weeks. Prior to analysis, the removal of inorganic carbon is essential, which is achieved without altering the NOM composition through sample acidification to pH 6 and subsequent N2-purging. The chromatographic separation employs a preparative TSK HW-50S column to achieve a limit of detection of 19.0 µgC dm−3 with an injection volume of 1350 mm−3. The method demonstrates linearity up to 10,000 µgC dm−3. Precision, trueness and recovery assessments are conducted using certified reference materials, model compounds, and real water samples. The relative measurement uncertainty in routine analysis ranges from 3.22% to 5.17%, while the measurement uncertainty on the bias is 8.73%. Overall, the HPSEC-TOC represents a reliable tool for NOM fractions analysis in both treated and untreated ground and surface water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soils under anthropic uses showed more remarkable changes in soil properties with rainfall seasonality than soils under natural páramo. • Land-use change from natural vegetation to potato and onion crops followed by fallow reduces soil organic matter and water content and increases bulk density. • Land-use change could impair the ability of páramo catchments for streamflow buffering and this could increase surface runoff and reduce base flow. High-Andean páramos deliver essential ecosystem hydrological services from a combination of soil, vegetation, and climate characteristics, particularly in their natural state. However, agricultural activities considerably affect the páramo's ability to store, regulate, and supply water. Although there is information on the effect of potato crops (Solanum tuberosum) on páramo soils' properties, the effect of spring onion (Allium fistulosum) crops has been studied less. In addition, dry páramos are underrepresented in existent páramoś research. This study assessed the effect of rainfall seasonality (RS) and land-use change (transformation from páramo vegetation to crops) on soil hydrophysical properties associated with hydrological services (streamflow buffering) in a dry páramo in the Eastern range in Colombia. Six dominant land uses were studied: natural páramo vegetation (low slope, steep slope, and dense shrublands) and anthropic use (onion crops, potato crops, and fallow). An in-depth random stratified discrete design (0–5, 10–15, and 20–25 cm) was used to collect samples for analysis of soil organic matter (SOM), bulk density (BD), pH, and electrical conductivity (EC). Hydrophysical properties were measured at the soil surface: water retention capacity (WRC), structural stability (SS), and infiltration capacity (IC). Soils under anthropic uses showed more remarkable changes in soil properties with RS than soils under natural páramo. On the other hand, land-use change from natural vegetation to potato and onion crops followed by fallow leads to a reduction in SOM (9.8 %) and an increase in BD (0.19 gcm−3), especially at the surface level. In addition, this leads to a loss of WRC (20 % at field capacity), an increase in unstable aggregates (13 %), water erosion, and a loss of IC (44 mmh−1). This paper demonstrates the impact of land use on soil hydrophysical properties that compromise the maintenance of hydrological services and contributes to a better understanding of the complexity of Andean páramos. [ABSTRACT FROM AUTHOR]

The excessive accumulation of foam in wastewater treatment plant (WWTP) tanks can impede proper aeration, hindering the effective removal of organic matter from the water. This study proposes a novel technique to monitor in real time the presence of foams in WWTP tanks by using texture segmentation models trained with centralized and federated approaches. These models are designed to segment the foam and quantify the percentage of foam coverage across the entire tank surface. This data provides plant operators with crucial information for identifying the optimal time for foam removal. The proposed methodology is integrated into an image processing pipeline that involves acquiring images using a PTZ camera, ensuring the absence of anomalies in the captured images, and implementing a real-time communication method for event notifications to plant operators. The models exhibit noteworthy performance, achieving an 86% Dice score in foam segmentation, with comparable results obtained through both centralized and federated training. Implemented in a wastewater treatment plant, this integrated pipeline enhances operational efficiency while concurrently reducing costs. [ABSTRACT FROM AUTHOR]

This study delves into the critical issue of water pollution caused by the presence of metal oxides, synthetic dyes, and dissolved organic matter, shedding light on their potential ramifications for both the environment and human health. Metal oxides, ubiquitous in industrial processes and consumer products, are known to leach into water bodies, posing a significant threat to aquatic ecosystems. Additionally, synthetic dyes, extensively used in various industries, can persist in water systems and exhibit complex chemical behavior. This review provides a comprehensive examination of the toxicity associated with metal oxides, synthetic dyes, and dissolved organic matter in water systems. We delve into the sources and environmental fate of these contaminants, highlighting their prevalence in natural water bodies and wastewater effluents. The study highlights the multifaceted impacts of them on human health and aquatic ecosystems, encompassing effects on microbial communities, aquatic flora and fauna, and the overall ecological balance. The novelty of this review lies in its unique presentation, focusing on the toxicity of metal oxides, dyes, and dissolved organic matter. This approach aims to facilitate the accessibility of results for readers, providing a streamlined and clear understanding of the reported findings. [ABSTRACT FROM AUTHOR]

To reuse water and reduce water pollution, such as chemical oxygen demand (COD), total suspended solids (TSS), PO 4 , NTU, and NO 3 , advanced wastewater treatment technologies (a combination of coagulation (FeCl 3) and adsorption (Activated Carbon (AC))) are attractive. Considering that water reclamation can help provide an irrigation system for crops and domestic purified water, removing organic matter and nutrients prior to wastewater reuse is fundamental. In order to remove contaminants like organic matter and nutrients from wastewater, advanced wastewater treatment processes are recommended. The purpose of this paper is to investigate various doses of AC and FeCl 3 in wastewater treatment and study the optimum conditions for the removal of COD, TSS, PO 4 , NTU, and NO 3. Furthermore, the evaluated FeCl 3 '/AC's optimum functioning pH ranges from 6.5 to 8.0, and their optimum working times range from 2.5 to 5.5 h. The optimum concentrations of AC were 0.1–25 g/L and 0.1–5 g/L of FeCl3. The most significant COD elimination rate (98%), the highest TSS elimination efficiency (94%), NTU elimination performance (99%), PO4 elimination (99%), and NO3 elimination (67%), among the investigated FeCl 3 and AC. Secondly, the effects of operational variables such as AC, FeCl 3 , time, and solution pH were modeled, optimized, and evaluated using response surface techniques based on the D-Optimal design. Input from the response surface approach findings was used to develop an artificial neural network-based prediction model and Non-dominated Sorting Genetic Algorithm II (NSGA-II). [Display omitted] • COD, TSS, PO4, NTU, and NO3 were effective FeCl3 and PAC coagulants at optimal conditions. • Co-degradation outputs are compared to experimental results using ANNs and RSMs. • The RSM correlation coefficient was 0.973 and the ANN correlation coefficient was 0.997. • Activated carbon and FeCl3 are suitable technologies for the decline of organic matter in advanced water treatment. [ABSTRACT FROM AUTHOR]

Coal gasification technology is the core of clean and efficient utilization of coal, while coal gasification fine ash (CGFA) is the solid waste inevitably produced in the coal gasification process. Due to the high residual carbon content and water retention of CGFA, the solubility of its silica-aluminium-calcium-containing minerals is poor, which affects its potential cementing properties in construction materials. In this paper, the basic physicochemical properties were investigated, and it was found that small particles of CGFA (CGFA-S) had more active mineral components, lower residual carbon content (17.17%) and weaker water retention (6.91%), which facilitated the removal of impurities and water. In addition, the best effects were achieved at a heat treatment temperature of 650 °C, which exposed the minerals and increased the solution solubility, and the leaching concentrations of Si4+, Al3+, and Ca2+ increased by 21.2%, 44.6%, and 97.8%, respectively. However, when the temperature was too high (815 °C), the minerals recrystallized, leading to structural instability and dissolution difficulties, and the concentrations of the three major ions were reduced by 84.4%, 82.0%, and 42.2%, respectively, compared with the control.Finally, the optimal heat treatment temperature was 650 °C, with the highest exothermic hydration rate (11.92 mW/g) and the highest cumulative exothermic heat (199.81 J/g). The hydration products were tightly bound, and the cement mortar specimens had the highest compressive strength, with a 28d strength of 45.4 MPa. • The physicochemical properties of CGFA were analyzed based on particle size. • The extraction effect and microstructure of ash in CGFA were tested. • The hydration activity of thermally modified CGFA was investigated. [ABSTRACT FROM AUTHOR]

There is still no direct evidence for the existence of water ice and organic matter on the moon. The main goal of developing a miniature time-of-flight mass spectrometer (TOF MS), Lunar Water Molecular Analyzer Mass Spectrometer (LWMA MS), is to detect water ice, organic matter and other chemical components in situ on the moon. The miniature LWMA MS in this paper is composed of sampling introduction tube, gas charge tube, ion source, TOF mass analyzer and detector. The SIMION software was used to simulate the miniaturization design of the ion source and mass analyzer. Meanwhile, the developed miniature TOF MS was evaluated systematically. Its resolution is 151 for water and 163 for nitrogen, the mass range is from 1 to 500 amu, the stability of water is 3% during 12 h. Moreover, it was proved that the developed LWMA MS is able to detect water ice and organic matter through the experiments of the lunar soil simulant. • A miniature LWMA MS is developed. • The resolution is 151 for water and 163 for nitrogen. • The mass range is from 1 to 500 amu. • The stability of H 2 O is 2.98% for 12 h. • The designed LWMA MS is able to detect the water ice and organic matter in situ lunar investigations. [ABSTRACT FROM AUTHOR]

The alpine area has become a sensitive indicator and amplifier of global climate change and human activities because of its unique geographical and climatic conditions. Being an essential part of biochemical cycling, dissolved organic matter (DOM) could effectively help understand the process, structure, and function of alpine aquatic ecosystems. Due to the low content and sampling difficulties, the analysis of DOM in alpine water demands high sensitivity with low sample volume, which has not been comprehensively reviewed. This review summarizes the DOM sampling, pretreatment, and analysis methods involving the characterization of concentration, spectroscopy, and molecular structure. Overall, conventional parameters are the basis of advanced characterization methods. Spectroscopic tests can reveal the optical properties of DOM in response to lights from ultraviolet to infrared wavelengths, to distinguish the chemical composition. Molecular structure characterizations can provide microscopic information such as functional groups, element ratios, and molecular weights. The combination of multiple methods can depict DOM composition from multiple perspectives. In sum, optimized sampling and pretreatment, high-sensitivity molecular characterization, and method integration are crucial for effectively analyzing DOM components in alpine waters. These perspectives help to standardize the DOM characterization process and to understand the correlation between DOM composition and its properties, as well as the migration and transformation of DOM. [ABSTRACT FROM AUTHOR]

Shale oil, an important component of unconventional oil and gas resources, mainly exists in the storage spaces such as shale pores, microfractures, etc. Porosity is commonly used to quantitatively describe the storage space of shale oil and is a key parameter in reservoir evaluation. However, there are significant differences in the results by existing experimental methods for porosity measurement, and moreover, it is difficult to compare the porosity obtained by the experimental measurement method with the logging calculation method. It is urgent to explore reasons for the differences in porosity measurement between various porosity experiments and logging calculations of the shale oil reservoir, and propose an effective method for shale oil reservoir to characterize porosity. In this research, core samples of shale oil reservoirs from the Lianggaoshan Formation of the Sichuan Basin were selected to measure the porosity by means of experimental methods including helium gas charging, saturation liquid method, nuclear magnetic resonance (NMR), etc. Meanwhile, porosity was calculated using the combination method of lithology scanning (LS) logging and conventional logging as well as the NMR logging method. Subsequently, porosity experimental results and logging calculation results were compared to clarify the applicability of various porosity characterization methods. The research results indicate that: 1) The porosity measurement results by the saturation liquid method and the NMR experimental method are close, both greater than that using the helium gas charging method; 2) The hydrogen signal of the dry-state sample is significant in the NMR experiment, mainly originating from organic matter and clay minerals; 3) The NMR short relaxation component in the water-saturated state primarily reflects the signal of organic matter and clay mineral matrix, while the long relaxation component reflects the pore fluid component; 4) After deducting the NMR signal of the dry-state core, the core NMR porosity measurement results under the water-saturated state agree well with that using the saturation liquid method, which is an indicative of effective reservoir porosity; 5) The NMR logging is limited by its echo spacing and cannot reflect the signal from organic matter and the crystal water in clay minerals at T2 < 0.3 ms. Taken together, the porosity measurement method of subtracting the dry-state NMR signal from the water-saturated state NMR signal is considered effective and can be used to reflect the porosity of shale oil reservoirs in the Lianggaoshan Formation of the Sichuan Basin. [ABSTRACT FROM AUTHOR]

The carbon (C) fixed by crops, which is exported with harvest and retained as postharvest residues in a field, is important for calculating the C balance. The aim of this study was to determine the effect of water availability on the C content in whole wheat plants. In a three-year field trial, the weights of grain, straw, chaff, stubble, and roots of two cultivars of winter wheat (Triticum aestivum L.) and one cultivar of einkorn wheat (Triticum monococcum L.) and their carbon contents were determined in water stress, irrigation, and rain-fed control treatments. The water availability, year, and cultivar had a significant influence on the C content in aboveground plant parts, but the effect of water on grain C was weak. The C content decreased with irrigation and increased with drought, but the differences were small (at most, 3.39% in chaff). On average, the C contents of grain, straw, chaff, and roots reached 45.0, 45.7, 42.6, and 34.9%, respectively. The amount of C exported with grain and left on the field in the form of postharvest residues depended on the weight of the total biomass and the ratio of grain to straw and residue. Whole plant C yield reached 8.99, 7.46, and 9.65 t ha−1 in rain-fed control, stressed, and irrigated treatments, respectively, and 8.91, 9.45, and 7.47 t ha−1 in Artix, Butterfly, and Rumona, respectively. Irrigation significantly increased the C content in grain and straw (but not in chaff, stubble, and roots) in comparison with water shortage conditions. On average, a grain yield of 1 t ha−1 corresponded to an average export of 0.447–0.454 t C ha−1 in the grain of all cultivars and inputs of 0.721, 0.832, and 2.207 t C ha−1 of residue to the soil in the form of straw and postharvest residue in the two cultivars of common wheat and one of einkorn. The results of the study provided reliable data for the calculation of the C balance of wheat under conditions of different water availability. [ABSTRACT FROM AUTHOR]

Verticillium dahliae is a soilborne pathogen that causes significant losses in olive crops in northwestern Argentina. Biological control through antagonistic microorganisms such as Trichoderma has great potential in the management of Verticillium wilt of olive. This investigation aims to isolate, identify and characterize native Trichoderma strains for biocontrol of V. dahliae. Thirty-nine Trichoderma strains were isolated from soils of olive orchards and natural areas and they were morphologically and molecularly characterized. Desired attributes for plant growth and bioprotection, such as indole acetic acid (IAA) production, endophytism and antagonistic potential against the pathogen were evaluated. Thirteen Trichoderma species were identified, belonging to the Trichoderma, Longibrachiatum, Virens, and Harzianum clades. Physiological characterization revealed that fourteen strains produced IAA while ten showed endophytic capacity. The antagonistic parameters quantified were very variable: eight strains showed high growth inhibition values (PI > 65%), while six strains reached mycoparasitism (PM) values higher than 90% for both pathogens. Three endophytic strains exhibited IAA production and antagonistic activity against V. dahliae, becoming potential candidates for bioprotection of olive orchards. Olive cultivation in the arid regions of northwestern Argentina is subjected to strong stress conditions mainly due to the type of soils with low organic matter content and water retention. Thus, selected Trichoderma strains with more than one beneficial attribute are a fundamental tool for sustainable olive cultivation, not only as antagonists of emerging pathogens but also as mitigators of abiotic stress conditions that prevail in these environments. [ABSTRACT FROM AUTHOR]