Industrial symbiosis and eco-industrial park have been developed for decades and have significant economic and environmental effects in China. To research the evolution of industrial symbiosis and ...eco-industrial park construction, and summary the drivers and characteristics of industrial symbiosis development in China, this study uses the National Demonstration Eco-Industrial Park, namely, the Rizhao Economic and Technology Development Area (REDA), as a case study to introduce the industrial symbiosis development process and to research the evolution of industrial symbiosis and eco-industrial park construction, and summarizes the drivers and characteristics of industrial symbiosis development in China. Based on in-depth investigation of enterprises and the government in REDA, three stages (1991–2002, 2003–2006, 2007–2011) of industrial symbiosis development are identified, 31 inter-firms symbiosis performances involving cereal oil and food, machinery, pulp and paper, textile and garment, wine refining, and biochemical industries were formed since REDA was founded in 1991. Results show the environmental benefits of industrial symbiosis performances in 2011, and argue that economic benefits, mainly resulted from stricter environmental standards, tax preference, benefits from material substitution, and financial subsidies, is the critical driver for the stakeholders to participate in industrial symbiosis. The action of governments in industrial symbiosis development is to constituting strict environmental standards, resource comprehensive utilization schemes, financial support and circular economy and eco-industrial park planning guidance. This article provides some unique characteristics of industrial symbiosis growth in a developing country from enterprises and government aspects.
•A network with 31 industrial symbiosis performances formed since 1991 to 2011 in China is introduced.•The development process of industrial symbiosis could be identified into three stages (1991–2002, 2003–2006, 2007–2011).•The main driver for stakeholders to be involved in industrial symbiosis is economic benefit.•The role of government in industrial symbiosis development is to formulate policies and give financial support.
A life cycle assessment was carried out to estimate the environmental impact of municipal solid waste. Four scenarios mostly used in China were compared to assess the influence of various ...technologies on environment: (1) landfill, (2) incineration, (3) composting plus landfill, and (4) composting plus incineration. In all scenarios, the technologies significantly contribute to global warming and increase the adverse impact of non-carcinogens on the environment. The technologies played only a small role in the impact of carcinogens, respiratory inorganics, terrestrial ecotoxicity, and non-renewable energy. Similarly, the influence of the technologies on the way other elements affect the environment was ignorable. Specifically, the direct emissions from the operation processes involved played an important role in most scenarios except for incineration, while potential impact generated from transport, infrastructure and energy consumption were quite small. In addition, in the global warming category, highest potential impact was observed in landfill because of the direct methane gas emissions. Electricity recovery from methane gas was the key factor for reducing the potential impact of global warming. Therefore, increasing the use of methane gas to recover electricity is highly recommended to reduce the adverse impact of landfills on the environment.
The combined application of plant Suaeda salsa and indigenous fungus Trichoderma asperellum on the treatment of a lead (Pb) and salinity (Na+ and Ca2+) co-contaminated soil was investigated by a ...flowerpot experiment. As demonstrated by plant growth and selected antioxidant parameters, S. salsa was able to tolerate and grow in the co-contaminated soil, especially bioaugmented with T. asperellum, which promoted plant growth (9–23% and 5–13% increases for plant height and fresh weight, respectively) and appeared to alleviate plant oxidative damage (7–85% and 7–49% decreases for plant malondialdehyde and peroxidase levels, respectively). The SDS-PAGE fingerprints indicated that the total protein contents of S. salsa were affected under Pb and salinity stresses. The interactions of Na+ and Ca2+ ions on the phytotoxicity of Pb remained hormesis phenomenon that low-dose alleviation and high-dose enhancement. The analysis of phytoextraction parameters and bioavailability demonstrated that Pb was mainly concentrated in plant roots and poorly translocated, indicating the phytostabilization served as a major repair pathway. On the contrary, the Na+ and Ca2+ ions were concentrated in plant by the following order: shoot > root. Moreover, bioaugmentation of planted soil with T. asperellum generally led to the 9–42%, 13–58%, and 19–30% decreases of plant Pb, Na+, and Ca2+ concentrations and translocations, respectively, as well as a 6–21% decrease of soil Pb bioavailability. This study provided a bioaugmentation-assisted phytoremediation technique to make up the deficiencies of the long-term remediation for heavy metals and salinity.
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•The bioaugmentation-assisted phytoremediation was a suitable treatment strategy.•Trichoderma asperellum promoted plant growth and alleviated plant stress.•Phytostabilization served as a major phytoremediation pathway for Pb.•Saline ions were mobilized by Suaeda salsa while immobilized by T. asperellum.•Pb co-exposure with Na+ and Ca2+ ions increased the bioavailability of Pb.
This study aimed to explore the co-removal effect and mechanism of Cr(VI) and Cd(II) with an optimized synthetic material. The toxicity and accumulation characteristics of Cr(VI) and Cd(II) ...encountered in wastewater treatment areas present significant challenges. In this work, a rational assembly of sulfide-modified nanoscale zero-valent iron (SnZVI) was introduced into a biochar (BC), and a Cr(VI)–Cd(II) binary system adsorbent with high efficiency was synthesized. When the preparation temperature of the BC was 600 °C, the molar ratio of S/Fe was 0.3, the mass ratio of BC/SnZVI was 1, and the best adsorption capacities of BC-SnZVI for Cr(VI) and Cd(II) in the binary system were 58.87 mg/g and 32.55 mg/g, respectively. In addition, the adsorption mechanism of BC-SnZVI on the Cr(VI)-Cd(II) binary system was revealed in depth by co-removal experiments, indicating that the coexistence of Cd(II) could promote the removal of Cr(VI) by 9.20%, while the coexistence of Cr(VI) could inhibit the removal of Cd(II) by 43.47%. This work provides a new pathway for the adsorption of Cr(VI) and Cd(II) in binary systems, suggesting that BC-SnZVI shows great potential for the co-removal of Cr(VI) and Cd(II) in wastewater.
The biosorption and bioaugmentation performances of Mucor circinelloides were investigated under different contact time, initial metal(loid) concentration and species. The microbe-plant interaction ...appeared synergistic with enhancing plant growth and alleviating oxidative damages induced by lead, cadmium and arsenic. The bioaugmentation with M. circinelloides led to significant immobilization on lead, cadmium and arsenic as indicated by the decreases of metal(loid) transfer and bioavailability in plant-microbe aqueous system. Lead, cadmium and arsenic were mainly allocated on cell wall and a few parts entered into intercellular system, suggesting cell wall adsorption and intracellular bioaccumulation served as the main mechanisms of M. circinelloides. The adsorption kinetics and isotherms on lead, cadmium and arsenic were fitted well with the pseudo-second-order and Langmuir models, with the maximum adsorption capacities of 500, 15.4 and 29.4 mg·g−1 fungal biomass at pH 6.0 and 25 ℃. The optimum initial concentration and contact time were 300–10–20 mg·L−1 and 2 h. This study provides a basis for M. circinelloides as a promising adsorbent and bioaugmented agent for the cleanup of soil/aqueous environment contaminated with lead, cadmium and arsenic.
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•The adsorption best fitted with the pseudo-second-order and Langmuir models.•Most Pb, Cd and As allocated on cell wall via microbial passivation.•Microbe-plant interaction alleviated oxidative damage of combined Pb, Cd and As.•M. circinelloides reduced the translocation and bioavailability of Pb, Cd and As.•Bioaugmentation-assisted strategy improved phytoremediation of S. nigrum L.
● Higher concentrations of PS, PS-NH 2 and PS-SO 3H inhibited seed germination. ● PS, PS-NH 2 and PS-SO 3H influenced seedling growth in a dose-dependent manner. ● PS, PS-NH 2 and PS-SO 3H reduced ...essential nutrients uptake and plant quality. ● PS, PS-NH 2 and PS-SO 3H increased antioxidant enzyme activities and MDA content. ● Nanoplastic toxicity was related to surface charges.
Nanoplastic pollution has become a significant problem in farmland systems worldwide. However, research on the effects of nanoplastics (NPs) with different charges on field crops is still limited. In our study, NPs with different charges, including unmodified polystyrene nanoplastics (PS), positively charged polystyrene nanoplastics (PS-NH 2), and negatively charged polystyrene nanoplastics (PS-SO 3H), were investigated for their impacts on seed germination and seedling growth of rape. The results showed that seed water uptake (after 12 h), seed germination, seed vigour, and relative root elongation were all significantly reduced under exposure to NPs (200 mg/L). Similarly, remarkable decreases in plant biomass (root weight, shoot weight), growth (root length, plant height), photosynthesis ability (chlorophyll a, chlorophyll b, carotenoids), essential nutrient uptake (Fe, Mn, Zn, Cu), and plant quality (soluble protein, soluble sugar, crude fibre content) of rape seedlings were also observed after exposure to NPs. Among the three kinds of NPs, PS-NH 2 showed stronger effects. Moreover, superoxide dismutase, peroxidase, and catalase activities of rape seedlings were changed, and the content of malondialdehyde was significantly increased under exposure to NPs. Furthermore, positively charged PS-NH 2 showed stronger effects on the phenotype, physiology, biochemistry, nutrient uptake, and plant quality of rape. Notably, a comprehensive toxicity evaluation revealed that PS-NH 2 had the strongest toxicity to rape. The present study provides important implications for the interaction and risk assessment of NPs and crops in soil-plant systems.
The negative effects of heavy metals have aroused much attention due to their high toxicity to human beings. Migration and transformation trend of heavy metals have a close relationship with soil ...safety. Researching on migration and transformation of heavy metals in tailings can provide a reliable basis for pollution management and ecosystem restoration. Heavy metal speciation plays an important role in risk assessment. We chose Anshan tailings for our study, including field investigations and laboratory research. Four typical heavy metal elements of mine tailings {Fe (373.89 g/kg), Mn (2,303.80 mg/kg), Pb (40.99 mg/kg) and Cr (199.92 mg/kg)} were studied via Tessier test in vertical and horizontal direction. The main speciation of heavy metals in Anshan tailings was the residual. However, heavy metals have a strong ability for migration and transformation in vertical and horizontal directions. Its tendency to change from stable to unstable speciation results in increasing bioavailability and potential bioavailability. Fe, Mn, Pb and Cr showed different ability in the migration and transformation process (Mn > Pb > Fe > Cr) depending on the characteristics of heavy metals and physicochemical properties of the environment.
To meet the goal of sustainable development, many large steel enterprises in China have been relocated, leaving serious polycyclic aromatic hydrocarbon (PAH) pollution problems at the abandoned ...sites. In this study, the spatial distribution and potential health risks of PAHs in soils of a large steel enterprise in East China were studied. The total concentrations of 16 PAHs ranged from 93.96 to2.61E + 05 μg/kg. A total of 54.84% of the samples reached the level of severe pollution, with coking plants and iron works showing much more serious problems than other areas. The contribution levels of PAHs with high molecular weights were high, especially those of 4-ring PAHs. The toxic equivalent concentrations exceeded the values recommended by the Canadian guide. The average carcinogenic risk value of the whole region was greater than 10
–6
, indicating high carcinogenic risk. The above assessment indicates that the area must be remediated before further development occurs.
Perfluorooctanoic acid (PFOA) and arsenic are widely distributed pollutants and can coexist in the environment. However, no study has been reported about the effects of different arsenic species on ...the joint toxicity of arsenic and PFOA to soil invertebrates. In this study, four arsenic species were selected, including arsenite (As(III)), arsenate (As(V)), monomethylarsonate (MMA), and dimethylarsinate (DMA). Earthworms Eisenia fetida were exposed to soils spiked with sublethal concentrations of PFOA, different arsenic species, and their binary mixtures for 56 days. The bioaccumulation and biotransformation of pollutants, as well as eight biomarkers in organisms, were assayed. The results indicated that the coexistence of PFOA and different arsenic species in soils could enhance the bioavailability of arsenic species while reducing the bioavailability of PFOA, and inhibit the arsenic biotransformation process in earthworms. Responses of most biomarkers in joint treatments of PFOA and As(III)/As(V) showed more significant variations compared with those in single treatments, indicating higher toxicity to the earthworms. The Integrated Biomarker Response (IBR) index was used to integrate the multi-biomarker responses, and the results also exhibited enhanced toxic effects in combined treatments of inorganic arsenic and PFOA. In comparison, both the biomarker variations and IBR values were lower in joint treatments of PFOA and MMA/DMA. Then the toxic interactions in the binary mixture systems were characterized by using a combined method of IBR and Effect Addition Index. The results revealed that the toxic interactions of the PFOA/arsenic mixture in earthworms depended on the different species of arsenic. The combined exposure of PFOA with inorganic arsenic led to a synergistic interaction, while that with organic arsenic resulted in an antagonistic response. Overall, this study provides new insights into the assessment of the joint toxicity of perfluoroalkyl substances and arsenic in soil ecosystems.
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•Bioavailability of four As species in earthworms was enhanced by addition of PFOA.•Coexistence of PFOA and different As species reduced the bioavailability of PFOA.•Combined pollution with PFOA inhibited As biotransformation process in earthworms.•Combined exposure of PFOA with inorganic As species led to synergistic interaction.•Joint pollution of PFOA with organic As species resulted in antagonistic response.
Huangshui River (HSR) is the mother river of Qinghai province. Croplands and grasslands cover more than 76% of the total area, and highland agriculture and animal husbandry are the dominant ...industries. The use of pesticides, fertilizers, and feed additives increases the risk of heavy metal (HM) contamination. In this study, the concentration of HMs in the main stream and tributaries of HSR were investigated. The Positive Matrix Factorization model was used for source apportionment, and Health Risk Assessment method was used to assess the human health risks. To further analyze the effect of agriculture and animal husbandry on aquatic environment and human health, we considered agriculture and animal husbandry as two factors in the source apportionment process, defined the effect of the factors, established the calculation formula, and quantified the effects. The results show that the overall situation of aquatic environment in HSR is good; natural processes, traffic tail gas and atmospheric deposition, agricultural planting, industrial wastewater discharge, and animal husbandry are the main sources of HMs in the water. These HMs present noncarcinogenic and carcinogenic risks for infants. A total effect of agricultural and animal husbandry on HMs or HI in HSRB is approximately 20%, while on TCR is 40%. However, the effects of agriculture on the hazard quotient of arsenic, carcinogenic risk of nickel and lead, and that of animal husbandry on carcinogenic risk of cadmium were significant. This study can provide a theoretical basis for local managers of agriculture and animal husbandry to perform their work effectively.