The phosphorus (P) fraction and its release characteristics from sediment in response to flood events across different land covers (i.e., reclaimed land with dominant vegetation of Phragmites australis and/or Typha orientalis, grassland with dominant vegetation of annual and perennial forbs, and bare land) in the lakeshore of Chaohu Lake were investigated. The results indicated that the re-flooding of a restored wetland led to P release. IP (inorganic P) was the major P fraction in the soils pre-flood and post-flood. For all the soil samples, the rank order of P fractions was Ca-P (P associated with calcium) > OP (organic P) > Fe/Al-P (P bound to Al, Fe, and Mn oxides and hydroxides). During flooding, Fe/Al-P contributed the most as the P release source in the soils and to the P sources for the overlying water. In reclaimed land, Fe/Al-P release correlated significantly with soil pH. In grassland, Fe/Al-P release correlated significantly with soil pH and Al content. In bare land, Fe/Al-P release correlated significantly with Al and clay content. The max TP release rates were also significantly influenced by land cover, and the values in bare land, grassland, and reclaimed land were 9.91 mg P m⁻² day⁻¹, 8.10 mg P m⁻² day⁻¹, and 5.05 mg P m⁻² day⁻¹, respectively. The results showed that the P release processes might be regulated by different factors across different land covers, and that the re-introduction of vegetation during wetland restoration must be taken into account prior to flood events to avoid an undesirable degradation of water quality.

The feasibility of anaerobic digestion on the release of biogas and heavy metals from contaminated rice straw pretreated with NaOH solution was studied. The results show that NaOH pretreatment can significantly boost the release of biogas and heavy metals from rice straw using anaerobic digestion. Under the optimal conditions for biomass pretreated 6% (w/w) NaOH with a solid-to-solution ratio of 1:20, total biogas and methane yields of 446.3 mL/g and 263.5 mL/g volatile solids were achieved, which were 22.18% and 41.59% higher than those of the control without NaOH pretreatment, respectively, and the release percentages of Cd, Pb, Cu, and Zn from rice straw reached 86.95–97.69%. The release of heavy metals from rice straw can contribute to both the degradation of lignin by NaOH pretreatment and the utilization/transformation of lignocellulose via anaerobic digestion. The acidification levels and total volatile fatty acid contents significantly influence on the release of heavy metals. Based on the Illumina HiSeq sequencing analysis, the dominant phyla in the biogas residues were proteolytic (Bacteroidetes) and hydrogen-producing (Firmicutes) bacteria, while the growth of Methanospirillum and Methanosaeta in anaerobically digested effluent was promoted. The results revealed that anaerobic digestion combined with NaOH pretreatment is suitable for the disposal of heavy metal–contaminated biomass.

The remotion of hexavalent chromium in the form of chromate in aqueous solution was done using the aquatic plant Salvinia sp as biosorbent. The chemical modification of the Salvinia surface was performed by organosolv adapted method. The untreated Salvinia and the modified were characterized by infrared spectroscopy, Boehm titration, scanning electron microscopy, energy dispersive system, point of zero charge, surface area analysis, and porosity. Batch adsorption experiments were performed to observe the effects of pH, contact time, initial concentration, and temperature on the metal removal process. The characterization results show the chemistry modifically changed the modified Salvinia structure compared with untreated Salvinia. The adsorption test results showed the maximum adsorption capacity of 26.03 mg g⁻¹. The kinetic equilibrium was reached in about 3 h, and the better temperature and pH were 298 K and 7, respectively. The adsorption and kinetic models were Freundlich and pseud-second order, respectively. This study showed the Salvinia sp after the chemical treatment can be used with biosorbent for hexavalent chromate in the form of chromate, being a natural material with low cost and plentiful in the environment.

In this study, a composite remediation material for the enhanced reductive dechlorination (ERD) of 1,1,1-trichloroethane (1,1,1-TCA) in aqueous solution was prepared. This material was comprised of biochar as the carrier and adsorbent, and carrageenan (CG) as the embedding medium to entrap the organic carbon sources and zero-valent iron (ZVI). We determined the suitable biochar dosage and organic carbon source in the composite alongside the optimal preparation conditions. Furthermore, using an anaerobic microcosm study, we discussed the performance and possible mechanisms of the composite on 1,1,1-TCA removal in aqueous solution. From this, we found that the suitable dosage of biochar in water during the preparation of composite microspheres was 0.2% (w/v). Under this condition, the biochar had a strong capacity to adsorb 1,1,1-TCA with a removal efficiency of 84.2%. Soluble starch was selected as the appropriate organic carbon source, because starch-microspheres show an excellent slow-release effect in water. The optimal preparation conditions of microspheres were identified as follows: 2% CG (w/v) colloidal solution, 6% CaCl₂ (w/v) solution, and a 12-h curing time. After 25-day incubation with the composite prepared under optimized conditions, the removal efficiency of 1,1,1-TCA was 95.68%, which was 24.69% higher than that observed in the microcosm with a commercial remediation material. The scanning electron microscopy (SEM) images show that the amounts of ZVI and soluble starch inside the microsphere decreased obviously, while the biochar amount remained about the same. This indicates that 1,1,1-TCA in aqueous solution was mainly removed via soluble starch-enhanced biotic reductive dechlorination and ZVI-enhanced abiotic reductive dechlorination. The changes in microbial community structure demonstrate that the composite stimulated the activities of functional anaerobic bacteria, in particular, regarding dechlorination and fermentation abilities in the microcosm, therefore enhancing the anaerobic biodegradation of 1,1,1-TCA. This study suggests that the composite, entrapping biochar, ZVI, and organic carbon source in CG microspheres can significantly enhance the reductive dechlorination of 1,1,1-TCA in aqueous solution. We anticipate this novel remediation material could be successfully applied to the in situ ERD remediation of natural groundwater mainly contaminated with 1,1,1-TCA.

The widespread application of bisphenols (BPs) in the industry has made them ubiquitous in the environment, causing potential environmental risks. Its unknown impacts on human being have received more and more attention. In this study, we have assessed the metabolic effects of perinatal exposure to bisphenol A (BPA) and its substitutes (bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF)) in female mice adolescent offspring and female mice adulthood offspring. ¹H NMR-based serum metabolomics showed that metabolic profiles were disturbed with BPA and its three substitutes exposure in female mice adolescent offspring and female mice adulthood offspring. In addition, age-related metabolic effects were found based on changes in serum endogenous metabolites and metabolic pathways. Specifically, metabolic pathway analysis showed that major disturbed metabolic pathways in female mice adulthood offspring compare with female mice adolescent offspring also changed significantly. With the increase of age of the female mice offspring, changes in the metabolic pathways became more obvious in the BPA treatment group. Conversely, partially disturbed metabolic pathways were restored in the BPS, BPF, and BPAF treatment groups. In conclusion, perinatal exposure to BPA and its three substitutes significantly interferes with metabolic profiles and metabolic pathways, and this metabolic effects were age-related. These results offer more detailed information about the age-related metabolic effects of perinatal exposure to BPA, BPS, BPF, and BPAF in female mice offspring and provide data for systematic evaluation of the health risk assessment of BPA and its substitutes.

Industrialization and urbanization process has brought both economic development and a series of environmental problems. Hebei Province is a high haze area and one of the key areas of China’s “Blue Sky Defense” policy. As carbon emission is one of the most important factors causing haze, it is necessary to screen the influencing factors effectively to make quantitative analysis and predict carbon emissions in different degrees of coordination. Faced with the new situation of Beijing-Tianjin-Hebei coordinated development and more environmental constraints, this paper designs a system for predicting carbon emissions in Hebei Province innovatively using the data during 1990–2016. In the first step, 7 influence factors are determined by “graded screening.” Then, this paper improved the traditional support vector machine (SVM) by improved gray wolf optimizer (IGWO), and established IGWO-SVM model. Finally, the carbon emissions in Hebei Province from 2017 to 2025 are predicted under three stages of different cooperative development speed of 7 influence factors by the improved intelligent algorithm model. Based on the forecasting results, this paper put forward some pertinent opinions to provide theoretical basis for formulating relevant policies on carbon emissions in Hebei Province to effectively control carbon emissions from the source.

A number of studies has pointed to air pollution as an additional factor that could be associated with preterm birth. We assessed in this study the association between exposure to PM₂.₅ in ambient air during pregnancy and preterm birth in metropolitan areas of the state of Georgia, where the rate of preterm birth has been among the highest in the nation over the years. Birth data were obtained from the National Center for Health Statistics natality dataset. The study population consisted of 53,094 singleton live births between January 1 and December 31, 2004 in nine metropolitan counties of Georgia. Preterm birth was defined as birth, which occurs before 37 weeks of gestation. County-level daily air quality index (AQI) data obtained from the US Environmental Protection Agency (EPA) was used to estimate individual exposure levels of PM₂.₅ for each study participant based on the county of residence for the duration of the pregnancy. A multivariate logistic regression analysis was conducted to assess the association, adjusting for potential confounders. Of the infants whose mothers resided in the nine metropolitan counties of Georgia, 4543 (8.6%) were born preterm. A higher rate of preterm birth (9.8%) was observed in infants whose mothers were exposed to ambient PM₂.₅ with AQI values > 50 than the ones with AQI ≤ 50 (EPA standard for good air quality conditions). Mothers with exposure to PM₂.₅ at average AQI values greater than 50 during the entire pregnancy were at increased risk of preterm birth (odds ratio 1.15; 95% CI 1.07, 1.25), after adjusting for sex of infant, mother’s age, race/ethnicity, education, marital status, prenatal care, cigarette smoking, alcohol consumption, and season of conception. The study provides more evidence on the role of PM₂.₅ in preterm birth. Reducing exposure to ambient particulate matter, especially in urban areas, for pregnant women would be necessary to improve the health of infants.

One of the most undesired wastes is the human excreta due to the socio-environmental pressure. Otherwise, the nutriments contained in human excreta could be used as fertilizers to enrich the soil. Familial waterless litter composting toilets (FWLCT) are an alternative for locations where a centralized sewerage network cannot be provided or where there is a lack of standard urban infrastructure including roads, electricity, and water supply. The scientific researches on the composting techniques, the methods of control of the composting processors, and the rate of produced leachate are very limited. In this research, the composting systems included a feces and urine collection device. In each passage, the litter (carbonaceous material) is added to the excreta. Regularly, the buckets were emptied into a composting device located outside the house to which an additional portion of carbonaceous materials can be added. Monitoring was carried out on five rural and one urban familial composting areas in France for 1.5 years. The physiochemical and microbiological properties of the compost and leachate have been monitored and measured in compliance with the protocols. The results show that one of the main problems of this system of human excreta treatment is that the composting process does not achieve a significant rise in temperature and does not allow reaching the optimum temperatures (> 50 °C). Otherwise, from an agronomic point of view, the obtained compost is not rich enough in nutriments to be a good compost as soil fertilizer. But it can be used as a soil conditioner. The average leachate flux from the composters is 1.79 L/day. Because of the very short stay time in the piles, the leachate is contaminated by harmful bacteria and should be treated by another sanitation system.

The article Cellular distribution of cadmium in two amaranth (Amaranthus mangostanus L.) cultivars differing in cadmium accumulation, written by Keyu Chi, Rong Zou, Li Wang, Wenmin Huo and Hongli Fan, was originally published electronically on the publisher’s internet portal (currently SpringerLink)

In this work, a novel composite, ball-milled biochar (BMB) encapsulated in calcium-alginate (CA) beads (CA-BMB), was synthesized as an alternative adsorbent for the removal of methylene blue (MB) from an aqueous solution. Sorption performance was compared among CA, BMB, and CA-BMB composite with batch adsorption experiments. With 25% BMB and 75% alginate, the new composite resembled CA in MB adsorption. With an initial MB concentration of 50 mg L⁻¹, kinetics studies showed that 74% MB removal by CA-BMB was achieved within 8 h, followed by slow kinetics reaching 91% removal in 16 h. The adsorption kinetics was well explained by the Ritchie’s kinetic model, indicative of energetically heterogeneous solid surface of the composite. Adsorption isotherms of BMB, CA, and CA-BMB can all be fitted with the Langmuir models; the adsorption capacity of CA-BMB (1210.7 mg g⁻¹) was close to that of CA (1282.2 mg g⁻¹) and much higher than that of BMB alone (184.1 mg g⁻¹). The outstanding adsorption performance suggested that CA-BMB can serve as a low-cost and eco-friendly adsorbent for MB removal from an aqueous solution.