Environmental Science and Pollution Research - Landfilling is a critical method in managing massive generated C&D waste, and the appropriate selection of C&D waste landfill sites... 相似文献
Pennisetum sp. was employed as a model species to detect the growth and physiological response to cadmium (Cd) stress at different Cd concentrations (0, 20, 50, and 100 mg kg−1) in three types of soils (yellow brown soil, yellow soil, and red soil). Results showed that the growth of Pennisetum sp. was not significantly influenced by Cd in 20 mg kg−1, but significantly inhibited at higher Cd concentrations in three types of soils. Besides, the higher Cd concentrations, the lower root, stem, and leaf biomass. With Cd concentration of soil increasing, Cd content of root, stem, and leaf increased. Compared with no Cd, high Cd concentrations (50 and 100 mg kg−1) induced the physiological indices (photosynthetic rate, stomatal conductance, transpiration rate) and biochemical indices (nitrate reductase, glutamine synthetase, and glutamate synthase activities) decreasing, but the concentration of NO3− and NH4+ increasing. The activity of antioxidative enzymes (SOD, POD, and CAT) was disrupted and the content of malondialdehyde (MDA) increasing. Pennisetum sp. could protect cells from damage and maintain normal physiological metabolism via increasing the production of soluble sugar and soluble protein, but soluble proteins and soluble sugars were limited in high concentrations of Cd (50 and 100 mg kg−1). Moreover, the growth and physiological response to Cd are different in the three types of soils. The growth of Pennisetum sp. in yellow brown soil was better than that in other two soils, and the gas exchange rate, antioxidant enzyme activity, and nitrogen metabolism in yellow soil and red soil were more affected by Cd stress than that in yellow brown soil. Overall, Pennisetum sp. had certain tolerance and biosorption ability to Cd in different Cd concentrations and different types of soil. Hence, Pennisetum sp. was a suitable choice for Cd remediation, especially in yellow brown soil.
Mixed metal-containing waste, polychlorinated biphenyls (PCB) containing capacitors, printed circuit boards, steel mill dust and metal sludge were among the most common wastes exported from Taiwan. Before the implementation of the self-monitoring model programme of the Basel Convention (secretariat of the Basel Convention 2001) in the Asia region, Taiwan conducted a comprehensive 4-year follow-up project involving government authorities and the waste disposal facilities of the importing countries. A total of five countries and nine plants were visited in 2001-2002. The following outcomes can be drawn from these investigations. The Chinese government adopts the strategies of 'on-site processing' and 'relative centralization' on the waste management by tightening permitting and increasing site inspection. A three-level reviewing system is adopted for the import application. The United States have not signed the Basel Convention yet; the procedures of hazardous waste import rely on bilateral agreements. Importers are not required to provide official notification from the waste exporting countries. The operation, administration, monitoring and licensing of waste treatment plants are governed by the state environmental bureau. Finland, France and Belgium are members of the European Union. The procedures and policies of waste import are similar. All of the documents associated with transboundary movement require the approval of each government involved. Practically, the notification forms and tracking forms effectively manage the waste movement. 相似文献