A pot experiment was conducted in the Institute of Tianlong Ecology of Baotou City in Inner Mongolia, China, to investigate the effects of the application of biofertilizers and super absorbent polymers(SAP) on plant g...A pot experiment was conducted in the Institute of Tianlong Ecology of Baotou City in Inner Mongolia, China, to investigate the effects of the application of biofertilizers and super absorbent polymers(SAP) on plant growth and soil improvement in arid mining area soil. Two typical species, namely, Syringa oblata Lindl.(SO) and Medicago sativa L.(MS), were present in the Bayan Obo mining area and used as representatives of shrubs and herbaceous plants in the pot experiment.(1) Biofertilizers and SAP significantly increased the tree height, the ground diameter of SO, and the total biomass of MS and improved the soil fertility of the mining area, especially its biological fertility, compared with those of the control group(CK). The application of biofertilizers and SAP decreased the mining soil p H and significantly increased available nitrogen, available phosphorus, available potassium, and soil organic matter.(2) After 180 days of growth, the microbial population(bacteria, fungi, and actinomycetes) and soil microbial biomass carbon and nitrogen significantly increased. Microbial ratios C: N significantly decreased compared with those of CK.(3) T5 and T6 treatments with the following dosages might be the optimum selection for the improvement of the studied mining area soil: 20 g SAP + 15 g biofertilizers(SO), 100 g/m2 SAP + 150 g biofertilizers(MS); 20 g SAP + 30 g biofertilizers(SO), and 100 g/m2 SAP + 200 g biofertilizers(MS). This study provided a promising reference for conducting future field studies and the local vegetation restoration.展开更多
The widespread production and use of zinc oxide nanoparticles （ZnO-NPs） in recent years have posed potential threat to the ecosystem. This study aimed to investigate the ecotoxicological effect of ZnO-NPs on soil mi...The widespread production and use of zinc oxide nanoparticles （ZnO-NPs） in recent years have posed potential threat to the ecosystem. This study aimed to investigate the ecotoxicological effect of ZnO-NPs on soil microorganisms using laboratory microcosm test. Respira- tion, ammonification, dehydrogenase （DH） activity, and fluorescent diacetate hydrolase （FDAH） activity were used as ecotoxicological parameters. The results showed that in the neutral soil treated with 1 mg ZnO-NPs per g soil （fresh, neutral）, ammonification was significantly inhibited during the study period of three months, but the inhibition rate decreased over increasing time. Inhibition in respira- tion was observed in the first month of the test. In various ZnO-NPs treatments （1 rag, 5 rag, and 10 mg ZnO-NPs per g soil）, DH activity and FDAH activity were inhibited during the study period of one month. For both enzyme activities, there were positive dose-response relationships between the concentration of ZnO-NPs and the inhibition rates, but the curves changed over time due to changes of ZnO-NPs toxicity. Soil type affected the toxicity of ZnO- NPs in soil. The toxicity was highest in the acid soil, followed by the neutral soil. The toxicity was relatively low in the alkaline soil. The toxicity was not accounted for by the Zn2＋ released from the ZnO-NPs. Direct interaction of ZnO-NPs with biologic targets might be one of the reasons. The adverse effect of ZnO-NPs on soil micro- organisms in neutral and acid soils is worthy of attention.展开更多
基金supported by funds for Studies on Afforestation Materials with Super Absorbent Polymers in the Zhangjiakou Drought Area of Hebei Province,China(Grant No.2014HXFWSBXY025)the business cooperation research projects for Studies on Ecological Restoration Technology of Mine Restoration in Arid Area(Eco-Elion Restoration Co.,Ltd.&Beijing Forestry University)
文摘A pot experiment was conducted in the Institute of Tianlong Ecology of Baotou City in Inner Mongolia, China, to investigate the effects of the application of biofertilizers and super absorbent polymers(SAP) on plant growth and soil improvement in arid mining area soil. Two typical species, namely, Syringa oblata Lindl.(SO) and Medicago sativa L.(MS), were present in the Bayan Obo mining area and used as representatives of shrubs and herbaceous plants in the pot experiment.(1) Biofertilizers and SAP significantly increased the tree height, the ground diameter of SO, and the total biomass of MS and improved the soil fertility of the mining area, especially its biological fertility, compared with those of the control group(CK). The application of biofertilizers and SAP decreased the mining soil p H and significantly increased available nitrogen, available phosphorus, available potassium, and soil organic matter.(2) After 180 days of growth, the microbial population(bacteria, fungi, and actinomycetes) and soil microbial biomass carbon and nitrogen significantly increased. Microbial ratios C: N significantly decreased compared with those of CK.(3) T5 and T6 treatments with the following dosages might be the optimum selection for the improvement of the studied mining area soil: 20 g SAP + 15 g biofertilizers(SO), 100 g/m2 SAP + 150 g biofertilizers(MS); 20 g SAP + 30 g biofertilizers(SO), and 100 g/m2 SAP + 200 g biofertilizers(MS). This study provided a promising reference for conducting future field studies and the local vegetation restoration.
基金This work was supported by the National Natural Science Foundation of China （Grant Nos. 41071311, 41030529 and 41471391）, Program for New Century Excellent Talents in University of Ministry of Education of China （NCET-10-0200） and YKM Entrepreneurship Education Foundation.
文摘The widespread production and use of zinc oxide nanoparticles （ZnO-NPs） in recent years have posed potential threat to the ecosystem. This study aimed to investigate the ecotoxicological effect of ZnO-NPs on soil microorganisms using laboratory microcosm test. Respira- tion, ammonification, dehydrogenase （DH） activity, and fluorescent diacetate hydrolase （FDAH） activity were used as ecotoxicological parameters. The results showed that in the neutral soil treated with 1 mg ZnO-NPs per g soil （fresh, neutral）, ammonification was significantly inhibited during the study period of three months, but the inhibition rate decreased over increasing time. Inhibition in respira- tion was observed in the first month of the test. In various ZnO-NPs treatments （1 rag, 5 rag, and 10 mg ZnO-NPs per g soil）, DH activity and FDAH activity were inhibited during the study period of one month. For both enzyme activities, there were positive dose-response relationships between the concentration of ZnO-NPs and the inhibition rates, but the curves changed over time due to changes of ZnO-NPs toxicity. Soil type affected the toxicity of ZnO- NPs in soil. The toxicity was highest in the acid soil, followed by the neutral soil. The toxicity was relatively low in the alkaline soil. The toxicity was not accounted for by the Zn2＋ released from the ZnO-NPs. Direct interaction of ZnO-NPs with biologic targets might be one of the reasons. The adverse effect of ZnO-NPs on soil micro- organisms in neutral and acid soils is worthy of attention.
