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The improvement of batch photofermentative biohydrogen production was investigated using ultrasonication pre-treatment on a combined effluent of palm oil and pulp and paper mills. The effects of the amplitude (30–90%) and ultrasonication duration (5–60 min) were investigated in terms of their influences on the biohydrogen yield and chemical oxygen demand (COD) removal. The recommended ultrasonication parameters were found at the higher ranges of amplitude and duration (A70T45). Using A70T45 ultrasonication, the production of biohydrogen at 30 °C could be enhanced up to 8.72 mL H 2 /mL medium , with a total COD removal of 36.9%. During pre-treatment at A70T45, an energy input of 775 J/mL was supplied to disintegrate complex compounds into simpler structures. As a result, an increase in the soluble organic matter concentration was achieved, which led to enhanced biohydrogen production. On the other hand, the lowest biohydrogen yield (4.67 mL H 2 /mL medium ) and total COD removal (28.8%) were obtained in the control without pre-treatment. The enthalpy of the photofermentation process was estimated to be 141.1 kJ/mol with a threshold temperature of 30.9 °C based on a modified Arrhenius approach. [ABSTRACT FROM AUTHOR]

The paper industry is one of the most significant industrial branches that contributes to water pollution. Recent studies regarding the chemical composition of wastewaters from modern paper production sites are sparse, and organic contaminants originating from this source may remain undetected and uncontrolled. Therefore, for this study, non-target screening analyses of wastewaters from five different paper production sites were performed, including an extended analysis of one facility, for the identification of volatile non-polar to semi-polar organic contaminants. The identified contaminants were also traced in the adjacent river. Several specific agents related to paper production, including photoinitiators, ink and thermal paper constituents, were present in most wastewaters and were therefore considered to be characteristic paper industry contaminants. A couple of contaminants identified in this study are being reported for the first time and might be toxic, but have been neglected in previous studies. Bisphenol A and 2,4,7,9-tetramethyl-5-decyne-4,7-diol were found in untreated wastewaters, treated wastewater and in river water. Bisphenol A was present in river water downstream from where the paper industry discharges at a concentration that was reported to affect the reproduction of gastropods. Thus, our findings imply that paper industry discharges pose a risk to the populations of sensitive macroinvertebrates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adjusting different reaction temperatures of HTL, platform chemical and bio-oil fuel were produced. • The bio-oil yield of paper mill sludge reaches 44 wt% at 340℃. • The main composition aldehyde and ketone substances accounted for more than 40 %. As a kind of industrial hazardous solid waste, paper mill sludge (PMS) was hard to treated by conventional process because of its high moisture, high organic content and and high environmental risk. The hydrothermal liquefaction (HTL) shows excellent potential for the conversion to a wide variety of organic matter with high water contents including various kinds sludge into fuels or value-added chemicals. In this paper, the liquefaction potential for PMS under different reaction temperatures were investigated, and the products were classified into several main components based on the results of GC-MS. The results showed that the highest yield of bio-oil was 44 % (wt/wt dry PMS without ash) at 340 °C with simply compound composition. And the bio-oil product has above 26 % long chain hydrocarbon and 22 % cycloketones. It has potential for conversion to biomass platform compounds. It can be used as bio-fuel for heat recovery of alkali recovery system of paper mill. So, adjusting different reaction temperatures of HTL, the properties of products can meet the different requirements for platform chemical and/or bio-oil fuel. [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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

Chlorine disinfection in conventional water treatment plants in Egypt is a popular and inexpensive technique for disinfecting raw surface water before distribution to consumers. Nevertheless, the chlorination process in the presence of natural organic matter and decreased water quality due to uncontrollable population results in formation of high concentrations of carcinogenic disinfection by-products, from which trihalomethanes (THMs). In this paper, the water quality of Assiut drinking water network (ADWN) was assessed in terms of THMs studying different water quality parameters. An extended period simulation based on a modelling software WaterGEMS was employed to obtain the critical locations to be examined according to key parameters namely: water age, residual chlorine concentration, water velocity, and type of storage. The study concluded that THMs concentrations from all critical locations in Assiut drinking water network would not exceed the Egyptian regulatory threshold and US Environmental Protection Agency (EPA) guidelines. Even more, an investigated domestic roof tank should be critically operated under a planned scheme of monitoring and maintenance due to its deteriorated water quality. [ABSTRACT FROM AUTHOR]

Density-moisture relations are required while constructing roads and other structures and during farming operations. The Proctor test is the standard method of determining this relationship but other methods exist including the vibratory hammer or table and the soil vibratory compactor. The design, construction and testing of a soil vibratory compaction machine, which could produce maximum densities that mimic the Proctor test has been described in a previous paper by Leonard et al. (2019). A mechanism was designed and developed that vibrated the soil at a given time, amplitude and frequency and resulted in compacting the soil. It was determined that 17 Hz frequency operating at an amplitude of 1.7 mm for 5 mins were the ideal parameters to operate the compactor. However, it is still unclear whether the soil vibratory compactor could be used to test soils with varying clay contents with different water and organic matter contents. This paper utilises a vibratory compactor working at the predetermined parameters to test the density-moisture relations of two soils (sandy loam and clay) treated with peat at five different contents (0%, 4%, 8%, 12% and 16%) by mass and compacted at moisture contents which ranged from 5% to 55%. Similar tests were carried out using the standard Proctor test so as to compare the results. Results generally showed that although most bulk density values determined using the soil vibratory compactor were slightly lower (within a range of 0.02 to 0.06 t m-3) than the values from the standard Proctor test, density values from the two methods were perfectly related (r = 0.998). The soil vibratory compactor could then be used to estimate the bulk density values that are obtainable using the Proctor test. The major advantage of the constructed soil vibratory compaction equipment is that it could reduce the tedium involved in the standard Proctor soil compaction test. [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 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]

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]

Due to the climate change and human activity, the frequency and intensity of algal blooms have increased significantly. Recent studies have shown that during the bloom event, evaluated levels of cyanobacteria could infiltrate the drinking water treatment process and emerge in the filtered and disinfected water, thus threatening the safety of the drinking water supply. Among these concerned cyanobacteria, Microcystis aeruginosa is one of the most commonly detected species that cause algal bloom in a fresh water body. The present work was designed to investigate the transport and retention behaviour of Microcystis aeruginosa in a packed column to resolve the mechanisms that drive the transport behaviour of Microcystis under various operational conditions. The results showed that lab-cultured Microcystis aeruginosa could effectively break through the packed column regardless of ionic strength, media size or flow rate, as well as the presence of dissolved organic matter in the water under the conditions investigated. Such behaviour significantly contradicts those of fluorescent microspheres, which are commonly considered as ideal colloids. In addition, the combined impacts of pre-oxidation technologies and filtration on Microcystis aeruginosa removal were tested systematically. It was found that even the cells have been lysed/oxidized, no significant improvement of cell removals were observed in packed column. This paper provides a significant and comprehensive record of transport and retention behaviour of Microcystis aeruginosa in porous media. The results found herein suggest that in addition to the effort preventing toxin release/exposure during bloom events in source water, engineers and researchers should also pay attention to the transport and retention of Microcystis aeruginosa and other algal cells in filters to minimize the risk of breakthrough of cyanobacteria cells in the drinking water treatment process. Image 1 • Microcystis aeruginosa could breakthrough filters regardless of operational conditions. • DLVO theory do not adequately explain transport behaviour of Microcystis aeruginosa. • Presence of TOC could not impact the retention of Microcystis aeruginosa. • Oxidization process deactivated Microcystis aeruginosa but did not improve retention. • Transport behaviour of Microcystis aeruginosa is different to the one of microspheres. [ABSTRACT FROM AUTHOR]

• We use emergy analysis model to evaluate the ecosystem services. • The services supply and flow between ecosystems and urban area were identified. • Urban ecosystem has gradually transformed from a positive to a passive participant. • Attention should be paid to water supply and retention service of the wetland. Chongming Island, the largest alluvial island in the world, is an ecologically sensitive area. Due to its green space, farmland, estuaries and coastal wetlands and its proximity to the city of Shanghai (45 km, home to 24.2 million people), the island supports important agricultural and fisheries economies. This paper carries out an evaluation of the ecosystem services (ES) on Chongming Island, Shanghai, based on the emergy analysis method, identifying the service supply and flow between ecosystems and urban area. Results show that from the ecosystem-type perspective, the tidal wetland ecosystem provides the most service to Chongming Island, accounting for 45.2% ES emergy in 2012, followed by the agricultural ecosystem (34.5%) and the freshwater wetland ecosystem (6.3%). From ecosystem service-type perspective, water supply, flood storage and aquatic product supply are the main emergy outputs of the wetland ecosystem and account for 51.1%, 17.6% and 25.2% of the emergy, respectively. Food supply is the main emergy of the cropland ecosystem output and accounts for 58% of the emergy. Organic matter production and water retention are the main services provided by the forest ecosystem, accounting for 33.6% and 30.0% of the total emergy respectively. Based on the systematic emergy dynamic analysis, on the one hand, the wetland and forest ecosystems played more significant roles in water supply and retention while the cropland ecosystem had a less important role in food supply from 2002 to 2012. On the other hand, the urban ecosystem has gradually transformed from a positive to a passive participant in the role of supplier and user for ecosystem services. Finally, policy options are proposed to promote land use planning and restore/maintain ecosystem services. [ABSTRACT FROM AUTHOR]

The problem of environmental pollution is becoming more and more serious with the rapid development of industry and economy, especially the organic matter pollution in water. Thermodynamic analysis method is used based on this to analyze and study the pollution and treatment process of water organic matter in this paper. By proposing that the pollution essence is caused by the uneven distribution of sub-energy, the effect of organic pollutants treatment in four kinds of water bodies in Shenzhen City was analyzed by graphite material adsorption from the perspective of thermodynamic analysis. The experimental results show that the degree of organic pollution in the Jia reservoir of Shenzhen City is from high to low: Dasha River, campus pond, Jia reservoir, and B reservoir. When the ionic strength is 0.04 M, pH is 3.0, graphene loading is 2.5%, and reduced graphene oxide dosage is 200 mg/L, the degradation efficiency of organic pollutants in water is as high as 96.25%. [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]

• Water content data in liquid CO 2 between (-55 and -10)°C • Impact of impurities on the dehydration requirement. • Two different modelling approaches used to calculate water content CCS is expected to become an important contribution to the mitigation of carbon dioxide emissions. Transportation of CO 2 from the capture site to the permanent storage reservoir plays a key role, and transportation by ship is now viewed as a relevant alternative for certain combinations of captured CO 2 volume and distance. This paper presents experimental equipment, methods and new results for the water content of carbon dioxide and impure carbon dioxide in equilibrium with hydrates at temperatures between (-55 and -10)°C and pressures between (3 and 120) bar, hence in both vapour and liquid phases. The experimental data are compared with predictions from two thermodynamic models: the Cubic-Plus-Association equation of state and an approach using Multi-Fluid Helmholtz Energy Approximation (MFHEA) equations of state (EoS). In all cases, the hydrate-forming conditions are modelled by the solid solution theory of van der Waals and Platteeuw. [Display omitted] [ABSTRACT FROM AUTHOR]

The growing development of technologies and processes for resource treatment and recovery is offering endless possibilities for creating new plant-wide configurations or modifying existing ones. However, the configurations’ complexity, the interrelation between technologies and the influent characteristics turn decision-making into a complex or unobvious process. In this frame, the Plant-Wide Modelling (PWM) library presented in this paper allows a thorough, comprehensive and refined analysis of different plant configurations that are basic aspects in decision-making from an energy and resource recovery perspective. In order to demonstrate the potential of the library and the need to run simulation analyses, this paper carries out a comparative analysis of WWTPs, from a techno-economic point of view. The selected layouts were (1) a conventional WWTP based on a modified version of the Benchmark Simulation Model No. 2, (2) an upgraded or retrofitted WWTP, and (3) a new Wastewater Resource Recovery Facilities (WRRF) concept denominated as C/N/P decoupling WWTP. The study was based on a preliminary analysis of the organic matter and nutrient energy use and recovery options, a comprehensive mass and energy flux distribution analysis in each configuration in order to compare and identify areas for improvement, and a cost analysis of each plant for different influent COD/TN/TP ratios. Analysing the plants from a standpoint of resources and energy utilization, a low utilization of the energy content of the components could be observed in all configurations. In the conventional plant, the COD used to produce biogas was around 29%, the upgraded plant was around 36%, and 34% in the C/N/P decoupling WWTP. With regard to the self-sufficiency of plants, achieving self-sufficiency was not possible in the conventional plant, in the upgraded plant it depended on the influent C/N ratio, and in the C/N/P decoupling WWTP layout self-sufficiency was feasible for almost all influents, especially at high COD concentrations. The plant layouts proposed in this paper are just a sample of the possibilities offered by current technologies. Even so, the library presented here is generic and can be used to construct any other plant layout, provided that a model is available. [ABSTRACT FROM AUTHOR]

• Simulation and validation of first principle based model. • Systematic selection of manipulated variable for control purpose. • Multiple model based control strategy implementation for the MFC to address nonlinearity of the system. Water and energy scarcity are among the most serious challenges currently faced by the society. Microbial fuel cell is one such a technology, which simultaneously produces water and energy from waste water or organic matters. A robust control strategy is needed for smooth and continuous operation of cell. In this paper, first principle based model of microbial fuel cell is simulated and validated with experimental data from the literature. Selection of the manipulated variable is carried out by analyzing the dynamic and steady state response of the cell. It is found that the inlet substrate flow rate is the most suitable manipulated variable among all the considered variables. A multiple model based control strategy is developed using various switching criteria such as recursive Bayesian, k-nearest neighbour, and Hotelling's T 2 methods. An efficacy of the proposed control scheme is tested on servo and regulatory problems and comparison of switching methods are presented. Settling time for positive and negative set points is found to be 133 and 93 h, respectively and shows 47.3% improvement over the single model linear controller. This work helps in understanding the dynamics of the cell and development of robust nonlinear control for the microbial fuel cell. [ABSTRACT FROM AUTHOR]

In the Pampas region of Argentina agriculture is dominated by intensive no-till (NT) soybean cropping which produce negative consequences on soil quality. A group of farmers started to use the Good Agricultural Practices (GAP) which include a higher crop rotation, use of winter cover crops and nutrient restoration. In this NT system earthworms have a significant role in soil functioning, particularly in organic matter cycling and soil structure formation. The aim of this paper was to examine the contribution of earthworm activity to the process of C incorporation and soil structure maintenance in soils with different NT variants of: NT with GAP for 30 years (NT + r30); NT with some of the GAP for 12 years (NT-r12) and NT with soybean monoculture (NTm). Also a natural grassland (NA) was sampled as a reference. Earthworm aggregates were obtained by gently separating them from surrounding soil. Fine (HOC) and coarse (POC) organic matter fractions, water-stable aggregates (WSA) and mean weight diameter (MWD) were calculated for earthworm aggregates and bulk soil. In all sites only one species (Aporrectodea caliginosa) was found, with higher density in the NA, followed by NT + r30, that had about 9 times more earthworms than NTm. The number of earthworm aggregates was higher in the NT + r30 followed by the NA, both showing differences with the other NT systems. The earthworm aggregates in NA and NT + r30 had significantly more POC than the surrounding soil (230% increase in NA and 100% NT + r30). Earthworm casts had higher values of MWD and WSA than physical soil aggregates in both NA and NT + r30 management treatments. Our results show the existence of a positive feedback loop we called earthworm-driven virtuous cycle. The increase in earthworm abundance promotes higher production of earthworm aggregates which are richer in organic matter and more water stable than the surrounding soil. This has favourable results in terms of soil quality but also increase crop yields (57% in maize and 18% in soybean), by means of biologically mediated soil processes, which is a highly desirable way to sustainability of agricultural production. Farmers, politicians and the whole society should pay more attention to soil as a key component supporting agricultural production by means of internal biological soil functioning. • The only earthworm species present in all treatments was Aporrectodea caliginosa s.s. • No-till with good agricultural practices (NT + r30) had 9 times more earthworms than NT monoculture. • Cast density was higher in NT + r30 followed by the natural grassland (NA) and NT monoculture. • Particulate organic matter content was 230 in NA and 100% in NT + r30 higher in casts than in bulk soil. • In both, NA and NT + r30, casts were more stable to water than physical aggregates. [ABSTRACT FROM AUTHOR]

The distribution of sulfide sulfur in different parts of Lake Baikal in 2014 and 2015 is analyzed. The concentration of sulfide sulfur in the bottom sediments varied from 0.002 to 0.830 mg/g dry weight (the average value is 0.042 mg/g). Maximum concentration of sulfide sulfur in the lake sediments were typical of the northern region, where the Upper Angara and Kichera rivers flow into, and of some stations on the profile along the Selenga River mouth as well as of the stations located in the zone of underwater discharge of wastewater from the town of Baikalsk and from the Baikalsk Pipe and Paper Mill closed in 2013. This is associated with the active inflow of organic matter to the water column and sediments in such zones. [ABSTRACT FROM AUTHOR]

To address the issues of eutrophication and the potential risk of phosphorus (P) shortage, it is essential to remove and recover P from P-containing streams to close this nutrient cycle. Electrochemical induced calcium phosphate (CaP) precipitation was shown to be an efficient method for P recovery. However, the influence of natural organic matter (NOM) is not known for this treatment. In this paper, the behavior of NOM and its effect on CaP precipitation was studied. In contrast to studies where NOM hindered CaP precipitation, results show that the interaction of NOM with CaP improves the removal of P, independent of the types of NOM. The P removal at the average increased from 43.8 ± 4.9% to 58.5 ± 1.2% in the presence of 1.0 mg L −1 NOM. Based on the yellow color of the CaP product, NOM is co-precipitated. The bulk solution pH with and without buffers has totally different effects on the precipitation process. Without buffer, CaP precipitates on the cathode surface in a wide pH range (pH 4.0–10.0). However, the precipitation process is completely inhibited when the bulk solution is buffered at pH 4.0 and 6.0. This is probably due to neutralization of OH − by the buffers. Regardless of the presence or absence of NOM and solution pH, the recovered products are mainly amorphous CaP unless the electrolysis time was increased to seven days with 4.0 A m −2 , in which crystalline CaP formed. These findings advance our understanding on the interaction of Ca, P and NOM species for the application of electrochemical method for P recovery from real wastewater. [ABSTRACT FROM AUTHOR]

Abstract The Wełnowiec municipal dump, Katowice, Poland, rehabilitated with coal waste, is self-heating and igniting. This paper presents a novel application of the use of electrical- and resistivity geophysical methods in the investigation of burning coal waste to help explain why the heating occurred. Geoelectrical methods allowed the internal structure of the dump to be revealed, and the municipal wastes and their rehabilitation cover containing coal waste to be differentiated. Instead of a planned 2.2-m-thick multi-barrier system, the cover consists of irregularly distributed material of varying thickness (<1 to 8 m) and organic carbon content (>5%). This caused the fire to arise 3–4 years after the coal waste deposition. In areas where the rehabilitation layer is <3 m thick, a landslide enabled oxygen access, initiating self-heating. Changes in conductivity clearly identify sites of active burning where measured conductivity values are more than twice those for parts of the dump with no thermal activity. Field observations in particular, complemented to a degree by petrographic, mineralogical and geochemical data, enabled four types of heating zones to be distinguished, namely, (1) initial zones of fire overtaking new volumes of coal waste, (2) active zones with temperatures < 400–500 °C in exhalation vents, (3) overburned zones characterized by long-lasting high temperatures (800-900 °C) and (4) short-lived zones, ephemeral (<1–2 months) with temperatures between 70 and 100 °C. The geophysical methods applied could not distinguish between these zones. The combined results strongly suggest that the use of coal waste as a remediation layer covering waste dumps should be prohibited. Coal waste which, by its nature, is too prone to unpredictable self-heating and self-ignition with the potential environmental consequences that follow. Graphical abstract Unlabelled Image Highlights • unexpected self-heating and ignition of coal wastes used for rehabilitation of the Wełnowiec municipal dump, Katowice, Poland • a novel application of the use of electrical- and resistivity geophysical methods in the investigation of burning coal waste • distinguishing of four self-heating zones based on field observations, complemented by petrography, mineralogy, geochemistry [ABSTRACT FROM AUTHOR]

Hot melt compression treatment is a new technology in which traditional pressure dehydration is combined with thermal effects to achieve improved liquid/solid separation with low energy consumption. A dewatering process combining the mechanical expression with the heating treatment of space solid waste is proposed in this paper. Temperatures of 130–180 °C and a mechanical load of 0–8 MPa were employed on the drying behavior of space solid waste and product distribution with a self-designed hot press experimental setup. Experimental results showed that mechanical compression employed at increased temperatures had revealed a significant benefit in water recovery, resulting in the highest reduction of 95.5% of the moisture content. Considering the dehydration efficiency, the dewatering process of solid waste showed a positive effect at 160 °C and 6 MPa with a residence time of 100 min. At the same time, the reusability and chemical evolution were characterized comprehensively. The results showed that the condensed water had great potential to be reused as drinking water in the space station. Moreover, from an integrated perspective involving gaseous emissions, oxygen-containing functional groups accounting for 51.58–76.01% were the main components of the gas products. Halohydrocarbon was identified as the key volatile pollutant during the process of hot compression. In conclusion, this study gives a detailed insight into the hot melt compression behavior of space waste and offers potential opportunities and benefits for space solid waste treatment. [Display omitted] • A dewatering process combining the mechanical expression with the heating treatment of space solid waste has been proposed. • To maximize energy efficiency, optimum condition could be controlled at 160 °C, 6 MPa, and 100 min respectively. • Hot pressing temperature intensified the conversion of organic matter in water. • Halohydrocarbon was identified as the key volatile pollutant. [ABSTRACT FROM AUTHOR]

Coastal embayments play a vital role in the global carbon cycle either as sources of organic matter to open sea or as carbon sinks due to the accumulation of organic matter in sediments. This paper describes a study of Luoyuan Bay, a typical semi-enclosed embayment with a total area of approximately 227 km 2 in a strong tidal environment. The analysed results indicate that the particulate organic carbon (POC) concentration in suspended particulate matter (SPM) varies from 0.57 mg/L to 1.33 mg/L at the bottom layer (0.5 MAB, meters above bed) and from 0.54 mg/L to 1.25 mg/L at the surface layer (0.5 MBS, meters below surface). The δ 13 C‰ ranges from −25.52‰ to −23.54‰ and exhibits different variations at the surface and bottom layers in spring and neap tides. The POC content in deposited particulate matter (DPM) varies from 0.62% to 2.95%, increasing from spring to neap tide, and the δ 13 C and C/N molar ratio are −25.29‰ ∼ −21.41‰ and 4.18–8.53, respectively. The settling fluxes of POC obtained by sediment trap decrease from 2.25 g/m 2 ·tide during the spring tide to 0.55 g/m 2 ·tide during the neap tide with a mean value of 1.41 g/m 2 ·tide during the observation, whereas the settling flux of SPM decreases from 456.76 g/m 2 ·tide during the spring tide to 37.12 g/m 2 ·tide during the neap tide. Combining the δ 13 C and C/N molar ratio, three end-members are recognized, i.e., freshwater algae and phytoplankton, marine algae and phytoplankton, and kelp-derived detritus. The mean contribution to POC from these three sources is 57.2%, 31.8% and 11.0% in SPM, and 39.9%, 35.0% and 25.1% in DPM, respectively. The POC from freshwater algae, phytoplankton and kelp-derived detritus is controlled by sediment dynamic processes. [ABSTRACT FROM AUTHOR]

Using a time-dependent phosphorus (P) budget model for the Baltic proper, describing sources and sinks at the external borders of the water column, one may compute the e-folding time T of the adjustment of the winter surface water P concentration c to abruptly changed total P supply. The restoration time TR = 3 T is introduced as a practical measure of the time it takes to achieve 95% of the change of c towards the final, equilibrium, state c . The P budget model, including an internal source emanating from deep anoxic bottoms, also shows that c is proportional to the total P supply to the water column. About 70% of present time total P supply to the Baltic proper comes from deep anoxic bottoms. If deep bottoms were kept oxygenated, this internal P supply would be turned off and the equilibrium concentration c would be reduced by about 70%. This should imply that the Baltic proper may be restored to a state determined by the external P supplies from land-based and oceanic sources. According to the model, restoration would take 10-15 years. Thereafter most of the equipment used for oxygenation may be shut off since also the deepwater oxygen demand by decomposition of fresh organic matter, would have decreased by about 70% implying that the deepwater would be kept oxic by the natural vertical circulation. The model presented in this paper provides a new science-based solution of the eutrophication problem of the Baltic proper, which is of great interest from a management point of view. [ABSTRACT FROM AUTHOR]

Organic matter (OM) has numerous geochemical and ecological functions in inland waters and can affect water quality. Different parameters of aquatic OM are measured with various methods as no single analytical tool can provide definitive structural or functional information about it. In the present paper we review different OM metrics used in the European Union (EU) lake surveillance monitoring programmes and assess their suitability to provide sufficient data about the brownification and enrichment with oxygen consuming substances in European lakes. In the EU Water Framework Directive (WFD), metrics of OM are not mandatory physico-chemical parameters, but only recommended parameters to characterize water transparency, oxygenation conditions or acidification status. Our analysis shows that, as lake OM is monitored under the WFD in only 14 countries, no Europe-wide conclusions on the situation regarding brownification and organic enrichment can be drawn based on these data. Applied parameters in lake surveillance monitoring programmes are biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), dissolved organic carbon (DOC), water colour (WCol), and yellow substance. Different national OM metrics used avoid getting a broad picture of lake OM concentration changes in Europe over the last decades. Furthermore, our results demonstrate that the possibilities to convert different OM parameters to each other are limited because empirical relationships between them are region-specific. OM sensors for continuous measurements and remote sensing surveys could improve the effectiveness of lake OM monitoring, especially its temporal and spatial representativeness. It would be highly suggested to include in lake monitoring programmes also methods (e.g. absorbance or fluorescence spectroscopy) allowing to characterize the composition of OM as it influences strongly the biogeochemical role of OM in lakes. [ABSTRACT FROM AUTHOR]

In this paper, we present the analysis of the ecological roles of detritus and suspended particulate matter in aquatic ecosystems. New data that have been obtained for freshwater ecosystems of the central part of Russian Federation (Moscow Region, e.g., Mozhaiskoe Reservoir) have been included in the analysis. These new data include the results of studies of samples of water and detritus from the aquatic ecosystems. The review analysis addresses both freshwater and marine ecosystems. The multifunctional important role of detritus in aquatic ecosystems has been shown and exemplified using data for aquatic bodies of different trophic level, from oligotrophic to eutrophic. [ABSTRACT FROM AUTHOR]

This paper shows there is excellent potential to remove organic carbon by biological activated carbon (BAC). In surface waters, the reported biodegradable dissolved organic carbon (BDOC) is low (5–21%) which matches with the removal efficiency of most BAC after prolonged operation. Hence, it is thought that organic carbon removal by BAC cannot be further improved. To understand the full potential, water was incubated over a long period with granules obtained from a column of saturated BAC, i.e., exposed to the same source water over 9 months. The prolonged incubation removed between 43 and 52% of dissolved organic carbon (DOC), out of which physical adsorption accounted for 14–17%. The traditional BDOC method removed only 12–15% of DOC. Highest percentage removal was obtained for waters from the smallest reservoir with the lowest retention time. However, a significant amount of biodegradable organic matters (BOM) are still present in the reservoirs having longest storage time. Lowest possible DOC at the end of incubation was controlled by the adsorbed organic matter on BAC granules as confirmed by the aseptic desorption test with Milli-Q water. The results indicated there is a significant potential of a BAC treatment to remove organic carbon, but the traditionally experienced limitations of BAC should be overcome. [ABSTRACT FROM AUTHOR]

Studying the thermodynamic properties of soil organic matter is a developing field that involves the measurement of the energy stored by the soil. Quantifying soil energy content is still challenging despite different methodological approaches are available to calculate that value. One of the options is the proximate analysis following the guidelines for the energetic characterization of biomass. However, proximate analyses are still unexplored for soils. In this paper, we investigate the potential of this analysis to contribute to study soil from a thermodynamic perspective. With that goal, 31 soil samples collected in mature oak forests following a depth transect were used for elemental, thermal and proximate analysis. Proximate analyses and energetic characterization were performed by simultaneous thermogravimetry and differential scanning calorimetry. These methods allowed fragmentation of the soil organic matter in water content, volatile matter, fixed carbon, and ash, as well as the quantification of the soil organic matter and energy content. Pearson's correlation showed significant relations among the proximate, the elemental components of soils and the energy. The equations relating all of these variables were calculated for soils from oak forests by partial least squares analysis. Equations representing the relationship between energy and the proximate fractions provide an additional alternative to calculate the heat of combustion of the soil organic matter. This value is the essential step for the thermodynamic characterization of soils. • Proximate analysis fractionates SOM in VM, FC and ash components. • The soil proximate fractions are sensitive to SOM evolution. • Soil proximate fractions correlate to soil elemental components and energy content. • Soil proximate analysis can yield indirect measurements of the soil energy. [ABSTRACT FROM AUTHOR]

This paper deals with the degradation of dyes wastewater via electrochemical oxidation on a novel anode. The result showed that electrochemical oxidation is effective for dyes wastewater treatment. Under the optimum condition, the TOC removal reached 51.66%. [ABSTRACT FROM AUTHOR]

Soil aquifer treatment (SAT) is a managed aquifer recharge system in which the quality of the feed water (stormwater or wastewater treatment plant effluent) is further improved during soil passage. This paper provides an overview of SAT systems for wastewater treatment and reuse, and summarises design, removal efficiencies and pre-and post-treatment options as well as cost aspects of SAT using infiltration basins. SAT is an environment-friendly and robust multi-contaminant removal system which is effective in removing pathogens, nitrogen, bulk organic matter and the majority of organic micropollutants. The contaminant removal efficiency of SAT system, however, depends on several factors including source water quality, local hydrogeological conditions and process conditions applied. The performance of SAT system can be further improved by proper site selection and appropriate design of its components including pre- and post-treatment. SAT serves as an environmental and psychological barrier for water reuse applications. It is equally attractive for developed as well as developing countries and flexible enough to allow adaptation to local requirements by combining it with conventional (above the ground) natural or engineered water and wastewater treatment technologies. [ABSTRACT FROM AUTHOR]

Seasonal algal blooms in drinking water sources release intracellular and extracellular algal organic matter (AOM) in significant concentrations into the water. This organic matter provides precursors for disinfection by-products (DBPs) formed when the water is subsequently chlorinated at the final disinfection stage of the potable water treatment process. This paper presents results of AOM characterisation from five algal species (three cyanobacteria, one diatom and one green) alongside the measurement of the DBP formation potential from the AOM of six algal species (an additional diatom). The character was explored in terms of hydrophilicity, charge and protein and carbohydrate content. 18 DBPs were measured following chlorination of the AOM samples: the four trihalomethanes (THMs), nine haloacetic acids (HAAs), four haloacetonitriles (HANs) and one halonitromethane (HNM). The AOM was found to be mainly hydrophilic (52 and 81%) in nature. Yields of up to 92.4 μg mg −1 C carbonaceous DBPs were measured, with few consistent trends between DBP formation propensity and either the specific ultraviolet absorbance (SUVA) or the chemical characteristics. The AOM from diatomaceous algae formed significant amounts of nitrogenous DBPs (up to 1.7 μg mg −1 C). The weak trends in DBPFP may be attributable to the hydrophilic nature of AOM, which also makes it more challenging to remove by conventional water treatment processes. [ABSTRACT FROM AUTHOR]

Energy, water and carbon are inextricably linked. The limited endowments, uneven temporal and spatial distribution of energy and water resources pose great challenges to China’s sustainable development. In this paper, a bottom-up model (China TIMES model) is developed to integrate China’s energy system with water resources, to project water demand in power sector and to assess the impacts of China’s Intended Nationally Determined Contributions (INDC) and water constraints on power generation portfolio out to the year 2050. The modelling results show that: (1) under reference scenario, electricity generation will increase from 4518 TW h in 2010 to 13,270 TW h in 2050, with CO 2 emission from 3.1 Gt to 6.1 Gt and water withdrawal from 59 Gm 3 to 104 Gm 3 ; (2) CO 2 mitigation target can help reduce water withdrawal in power sector by promoting the expansion of renewable technologies; (3) by affecting the cooling mixture, water cost has significant impact on water withdrawal in power sector; (4) when both CO 2 and water constraints are considered, renewable technologies will be more prevalent. [ABSTRACT FROM AUTHOR]

This paper examines the recovery of the enteric adenovirus human adenovirus 40 (HAdV 40) by cross-flow ultrafiltration and interprets recovery values in terms of physicochemical interactions of virions during sample concentration. Prior to ultrafiltration, membranes were either blocked by exposure to calf serum (CS) or coated with a polyelectrolyte multilayer (PEM). HAdV 40 is a hydrophobic virus with a point of zero charge between pH 4.0 and pH 4.3. In accordance with predictions from the extended Derjaguin-Landau-Verwey-Overbeek theory, the preelution recovery of HAdV (rpre) from deionized water was higher with PEMcoated membranes (rprePEM=74.8%±9.7%) than with CS-blocked membranes (rpreCS =54.1%±6.2%). With either membrane type, the total virion recovery after elution (rpost) was high for both deionized water (rpostPEM=99.5%±6.6% and rpost CS =98.8%± 7.7%) and tap water (rpostPEM=89%±15% and rpost CS =93.7%±6.9%). The nearly 100% recoveries suggest that the polyanion (sodium polyphosphate) and surfactant (Tween 80) in the eluent disrupt electrostatic and hydrophobic interactions between the virion and the membrane. Addition of EDTA to the eluent greatly improved the elution efficacy (rpostCS =88.6%±4.3% and rpostPEM=87.0%±6.9%) with surface water, even when the organic carbon concentration in the water was high (9.4±0.1 mg/liter). EDTA likely disrupts cation bridging between virions and particles in the feed water matrix or the fouling layer on the membrane surface. For complex water matrices, the eluent composition is the most important factor for achieving high virion recovery. [ABSTRACT FROM AUTHOR]

This paper presents a mathematical model based on the Anaerobic Digestion Model No. 1 (ADM1) to simulate the effects of nitrate concentration and hydraulic retention time (HRT) on the simultaneous carbon and nitrogen removal (SCNR) in anaerobic/anoxic reactor treating domestic wastewater. The model was calibrated using previously published experimental data obtained from anaerobic batch tests for different COD/ NO 3 − ratios. Model simulations were performed to predict the SCNR in a completely mixed reactor (CSTR) operating under mesophilic conditions (35 °C). Six different scenarios were evaluated to investigate the performance of the SCNR based on typical influent characteristics of domestic wastewater. The variables analyzed were chemical oxygen demand (COD) removal, nitrate concentration, methane production, nitrogen gas, volatile fatty acids (VFA) concentration, pH and percentage of COD used by the denitrifying and methanogenic microorganisms. The HRT was decreased stepwise from 15 to 4 h. The results indicate that Scenario (S5) with a COD/ NO 3 − ratio equal to 10 and an HRT equal to 15 h ensures the occurrence of the stable SCNR. Furthermore, the accumulation of denitrification intermediates and a significant reduction in the biogas production when the organic matter is limited was verified. [ABSTRACT FROM AUTHOR]

There is high concentration of organic matter in the antibiotic wastewater, and its COD is up to 10000–5000 mg/l, which is one of the more obscure typical waste water. In this paper, wet oxidation (WO) is applied to treat antibiotic wastewater in a reactor under the following conditions: reaction temperature – 210 to 270°C; H2O2 dosage – 100 to 700 mg/l, and reaction time – 1 to 7 min. The effect of the given experimental conditions on total organic carbon (TOC) removal was investigated. The results indicated that temperature is a key factor in reducing TOC. As the reaction time and H2O2 dosage increase, TOC removal rises. The optimum TOC removal reached 87.3% under the experimental conditions. The preliminary study of mechanism on antibiotic wastewater by WO is carried out. The results indicate that antibiotic wastewater by WO can be explained by free radical mechanism. [ABSTRACT FROM AUTHOR]

Regulation alters the characteristics of rivers by transforming parts of them into lakes, affecting their hydrology and also the physical, chemical, and biological characteristics and dynamics. Reservoirs have proven to be very effective retaining particulate materials, thereby avoiding the downstream transport of suspended sediment and the chemical substances associated with it (e.g. Carbon, C, or Nitrogen, N). The study of fluvial transport of C and N is of great interest since river load represents a major link to the global C and N cycles. Moreover, reservoirs are the most important sinks for organic carbon among inland waters and have a potential significance as nitrogen sinks. In this respect, this paper investigates the effects of a Pyrenean reservoir on the runoff, suspended sediment, C and N derived from the highly active Ésera and Isábena rivers. Key findings indicate that the reservoir causes a considerable impact on the Ésera–Isábena river fluxes, reducing them dramatically as almost all the inputs are retained within the reservoir. Despite the very dry study year (2011–2012), it can be calculated that almost 300,000 t of suspended sediment were deposited into the Barasona Reservoir, from which more than 16,000 were C (i.e. 2200 t as organic C) and 222 t were N. These values may not be seen as remarkable in a wider global context but, assuming that around 30 hm 3 of sediment are currently stored in the reservoir, figures would increase up to ca. 2.6 × 10 6 t of C (i.e. 360,000 t of organic C) and 35,000 t of N. Nevertheless, these values are indicative and should be treated with caution as there is incomplete understanding of all the processes which affect C and N. Further investigation to establish a more complete picture of C and N yields and budgets by monitoring the different processes involved is essential. [ABSTRACT FROM AUTHOR]

A hybrid moving bed biofilm reactor-membrane bioreactor (hybrid MBBR-MBR) system was studied as an alternative solution to conventional activated sludge processes and membrane bioreactors. This paper shows the results obtained from three laboratory-scale wastewater treatment plants working in parallel in the start-up and steady states. The first wastewater treatment plant was a MBR, the second one was a hybrid MBBR-MBR system containing carriers both in anoxic and aerobic zones of the bioreactor (hybrid MBBR-MBRa), and the last one was a hybrid MBBR-MBR system which contained carriers only in the aerobic zone (hybrid MBBR-MBRb). The reactors operated with a hydraulic retention time of 30.40 h. A kinetic study for characterizing heterotrophic biomass was carried out and organic matter and nutrients removals were evaluated. The heterotrophic biomass of the hybrid MBBR-MBRb showed the best kinetic performance in the steady state, with yield coefficient for heterotrophic biomass = 0.30246 mg volatile suspended solids per mg chemical oxygen demand, maximum specific growth rate for heterotrophic biomass = 0.00308 h-1 and half-saturation coefficient for organic matter = 3.54908 mg O2 L-1. The removal of organic matter was supported by the kinetic study of heterotrophic biomass. [ABSTRACT FROM AUTHOR]

• A visual platform that combined Raman spectrometer was built to observe water at temperatures from 293 K to 1013 K. • The extent of hydrogen bonding in liquid water and supercritical water were estimated. • Compared with temperature, density has a greater effect on the degree of hydrogen bonding in supercritical water. • Hydrogen bonds still exist in supercritical water even at temperature of 1013 K (ρ = 49.8 g/L). Supercritical water is widely used as a superior reactant or solvent in the gasification of biomass and coal. Research shows that hydrogen bonding could reduce the potential energy of chemical reaction between water molecules and organic molecules. However, it is still uncertain whether hydrogen bonds exist in supercritical water at the temperature of coal gasification process (above 873 K). In this paper, a high temperature and pressure visualization platform (T max = 1013 K) was built. The hydrogen bonding degree of water from liquid to supercritical is obtained in a wider temperature range. It is a remarkable fact that hydrogen bonds still exist in supercritical water even at temperatures as high as 1013 K. These hydrogen bonds mainly exist in the form of dimer and trimer, which is a significant factor that can't be ignored in the study of gasification mechanism of coal and organic matter in supercritical water. [ABSTRACT FROM AUTHOR]

The principal reason for the high energy costs for biological wastewater treatment is the poor transfer efficiency of oxygen to the bulk water phase. The current paper describes a biofilm reactor in which oxygen transfer to the bulk solution is avoided by alternating anaerobic submersed (2 h) and drained (1 h) operation of the biofilm. During the submersed phase the biofilm enriched for glycogen accumulating organism (GAO) stored the organic carbon (acetate) as poly-hydroxy-alkanoate (PHA). After draining the reactor, this carbon stored as PHA was biologically oxidised, using oxygen directly from the atmosphere. The 12 Cmmol/L (384 mg/L BOD) of acetate was completely removed during long term automated operation of the reactor for 9 months with a cycle length of 3.3 h. As the process specifically removes dissolved organic carbon but not N or P it could possibly be coupled with novel processes such as Anammox or nutrient recovery. [ABSTRACT FROM AUTHOR]

Dissolved-ozone flotation (DOF) is a tertiary wastewater treatment process, which combines ozonation and flotation. In this paper, a pilot-scale DOF system fed by secondary effluent from a wastewater treatment plant (WWTP) in China was used to study the effect of ozone dosage on the DOF process performance. The results show that an ozone dosage could affect the DOF performance to a large extent in terms of color and organic matter removal as well as disinfection performance. The optimal color and organic matter removal was achieved at an ozone dosage of 0.8 mg/l. For disinfection, significant improvement in performance could be achieved only when the organic matter removal was optimal. The optimal ozone dosage of at least 1.6 mg/l was put forward, in this case, in order to achieve the optimal color, turbidity, organic matter and disinfection performance. [ABSTRACT FROM AUTHOR]