Extraction of heavy metals from e-waste contaminated soils using EDDS

Environmental contamination due to uncontrolled e-waste recycling activities is drawing increasing attention in the world. Extraction of these metals with biodegradable chelant [S,S]-ethylenediaminedisuccinic acid （EDDS） and the factors influencing extraction efficacy were investigated in the present study. Results showed that the addition of EDDS at low pH （5.5） produced higher metal extraction than that at high pH （8.0） solution. Metal speciation analysis indicated that Cu was completely complexed with EDDS at different pH conditions with various amounts of EDDS applied. For Pb and Zn, at low EDDS dose of 0.304 mol/kg soil, they were present as Pb- and Zn-EDDS. However, at high EDDS dose of 1.26 mol/kg soil, most of Pb was bound with dissolved organic matter. Ca and A1 were found to be strong competitors for trace metals to EDDS at low application dose and low pH condition.

Environmental fate and effects of organophosphate flame retardants in the soil-plant system

Organophosphate flame retardants(OPFRs),as a replacement for polybrominated diphenyl ethers(PBDEs),are of increasing concern due to their high production over the years.Soil is the major environmental reservoir and interchange for OPFRs.OPFRs in soil could be transferred to the food chain,and pose potential ecological and human health risks.This review focused on the environmental fate and effects of typical OPFRs in the soil-plant system.We concluded that the sorption and transformation behaviors of OPFRs due to their crucial impact on bioavailability.The root uptake and translocation of OPFRs by plants were summarized with analyses of their potential affecting factors.The in planta transformation and potential ecological effects of OPFRs were also briefly discussed.Finally,we highlighted several research gaps and provided suggestions for future research,including the development of simulative/computative methods to evaluate the bioavailability of OPFRs,the effects of root exudates and rhizosphere microorganisms on the bioavailability and plant uptake of OPFRs,and the development of green and sustainable technologies for in situ remediation of OPFRs-contaminated soil.

Building the new international science of the agriculture-food-water-environment Nexus in China and the world

The multiple,complex and systemic problems of the agriculture-food-water-environment nexus(“Nexus”)are among the most significant challenges of the 21st century.China is a key site for Nexus research amidst profound socio-environmental problems.The policy implications of these problems have been authoritatively summarized elsewhere.This study presents discussions at an international workshop in Guangzhou that asked instead“What science is needed to deliver the growing policy commitments regarding these challenges?And,What changes are needed to the science itself?”Understanding and effective intervention regarding the Nexus calls for a paradigm shift:to a new kind of science of(capacity for)international,interdisciplinary,and impactful research working with and within complex socio-natural systems.We here argue that science must become proactive in approach,striving only for“minimal harm”not“silver bullet”solutions,and adopting an explicitly long-term strategic perspective.Together,these arguments lead to calls for reorienting science and science policy in three ways:from short-term remediation to longer-term optimization;from a focus on environmental threats to one on the opportunities for international collaborative learning;and toward supporting new forms of scientific career.We bring these points together by recommending a new form of scientific institution:a global network of collaborative Nexus Centres,under the umbrella of a global Food Nexus Organization akin to those of the human genome and proteome.

Effect of industrial robot use on China’s labor market:Evidence from manufacturing industry segmentation

This paper empirically investigates the impact of industrial robot use on China’s labor market using data from 13 segments of manufacturing industry between 2006 and 2016.According to the findings,the use of industrial robots has a displacement effect on labor demand in manufacturing industry.The specific performance is that for every 1%increase in industrial robot stock,labor demand falls by 1.8%.After endogenous processing and a robustness test,this conclusion remains valid.This paper also discusses the effects of industrial robots across industries and genders.According to the results,industrial robot applications have a more pronounced displacement effect in low-skilled manufacturing than in high-skilled manufacturing.In comparison to female workers,industrial robot applications are more likely to decrease the demand for male workers.Moreover,this paper indicates that the displacement effect is significantly influenced by labor costs.Finally,we make appropriate policy recommendations for the labor market’s employment stability based on the findings.