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991.
大亚湾大鹏澳海域C、N、BSi的沉积记录研究 总被引:3,自引:0,他引:3
研究了大亚湾大鹏澳海域鱼类养殖区、贝类养殖区以及核电站附近3个站位50~78 cm的柱状沉积物中生物硅(BSi)、总有机碳(TOC)、总氮(TN)等生源要素的垂直变化,以揭示人类活动对海洋环境影响的沉积记录。位于近岸海水养殖区的两个沉积柱中,近年来TOC含量呈明显上升趋势,而核电站附近海域略有下降。从TOC/TN比值判断(三个沉积柱平均分别为9.54、7.42、7.9),该海域TOC是陆源和水生两种来源的混合物。此外,养殖区上表层沉积物中水生有机碳(TOCa)含量呈明显下降趋势,而TOC/TN比值则上升,说明养殖区水生初级生产力及其对总初级生产力的贡献下降;相反,陆源污染所造成的陆源有机碳(TOCt)含量明显增加。在核电站附近海域,TOCa含量明显上升,TOC/TN和TOCt值下降,表明核电站的运行使水体初级生产力上升,陆源有机碳输入则减少。BSi、BSi/TOCa的垂直分布表明,海水养殖区硅藻对总初级生产力的贡献逐年上升,而核电站海域硅藻的贡献则下降。 相似文献
992.
993.
994.
A pentachlorophenol (PCP) mineralizing bacterium was isolated from the secondary sludge of pulp and paper mill and identified
as Pseudomonas stutzeri strain CL7. This isolate used PCP as its sole source of carbon and energy and was capable of degrading this
compound as indicated by stoichiometric release of chloride and biomass formation. P. stutzeri (CL7) was able to mineralize a high
concentration of PCP (600 mg/L) than any previously reported Pseudomonad with PCP as sole carbon source. As the concentration
of PCP increased from 50 to 600 mg/L, the reduction in the cell growth was observed and the PCP degradation was more than 90%
in all studied concentrations. This isolate was able to remove 66.8% of PCP from the secondary sludge of pulp and paper mill when
supplemented with 100 mg/L of PCP and grown for two weeks. This study showed that the removal e ciency of PCP by CL7 was
found to be very e ective and can be used in PCP remediation of pulp paper mill waste in the environment. 相似文献
995.
996.
ZHANG Yejian YAN Li QIAO Xiangli CHI Lin NIU Xiangjun MEI Zhijian ZHANG Zhenjia 《环境科学学报(英文版)》2008,20(5):558-564
Palm oil industry is the most important agro-industry in Malaysia, but its by-product–palm oil mill e uent (POME), posed a great
threat to water environment. In the past decades, several treatment and disposal methods have been proposed and investigated to
solve this problem. A two-stage pilot-scale plant was designed and constructed for POME treatment. Anaerobic digestion and aerobic
biodegradation constituted the first biological stage, while ultrafiltration (UF) and reverse osmosis (RO) membrane units were combined
as the second membrane separation stage. In the anaerobic expanded granular sludge bed (EGSB) reactor, about 43% organic matter
in POME was converted into biogas, and COD reduction e ciency reached 93% and 22% in EGSB and the following aerobic reactor,
respectively.With the treatment in the first biological stage, suspended solids and oil also decreased to a low degree. All these alleviated
the membrane fouling and prolonged the membrane life. In the membrane process unit, almost all the suspended solids were captured
by UF membranes, while RO membrane excluded most of the dissolved solids or inorganic salts from RO permeate. After the whole
treatment processes, organic matter in POME expressed by BOD and COD was removed almost thoroughly. Suspended solids and
color were not detectable in RO permeate any more, and mineral elements only existed in trace amount (except for K and Na). The
high-quality e uent was crystal clear and could be used as the boiler feed water. 相似文献
997.
Vegetable oil has the ability to extract polycyclic aromatic hydrocarbons(PAHs)from contaminated sandy soil for a remediation purpose,with some of the oil remaining in the soil.Although most of the PAHs were removed,the risk of residue oil in the soil was not known.The objective of this study was to evaluate the effects of the vegetable oil residue on higher plant growth and sandy soil properties after soil extraction for a better understanding of the soil remediation.Addition of sunflower oil and column ex... 相似文献
998.
Influence of environment and substrate quality on the decomposition of
wetland plant root in the Sanjiang Plain, Northeast China 总被引:1,自引:0,他引:1
The litterbag method was used to study the decomposition of wetland plant root in three wetlands along a water level gradient in the Sanjiang Plain,Northeast China.These wetlands are Calamagrostis angustifolia(C.aa),Carex meyeriana(C.ma)and Carex lasiocarpa (C.la).The objective of our study is to evaluate the influence of environment and substrate quality on decomposition rates in the three wetlands.Calico material was used as a standard substrate to evaluate environmental influences.Roots native to each we... 相似文献
999.
ZHANG Yejian YAN Li QIAO Xiangli CHI Lina NIU Xiangjun MEI Zhijian ZHANG Zhenjia 《环境科学学报(英文版)》2008,20(5)
Palm oil industry is the most important agro-industry in Malaysia, but its by-product-palm oil mill effluent (POME), posed a great threat to water environment. In the past decades, several treatment and disposal methods have been proposed and investigated to solve this problem. A two-stage pilot-scale plant was designed and constructed for POME treatment. Anaerobic digestion and aerobic biodegradation constituted the first biological stage, while ultrafiltration (UF) and reverse osmosis (RO) membrane units were combined as the second membrane separation stage. In the anaerobic expanded granular sludge bed (EGSB) reactor, about 43% organic matter in POME was converted into biogas, and COD reduction efficiency reached 93% and 22% in EGSB and the following aerobic reactor, respectively. With the treatment in the first biological stage, suspended solids and oil also decreased to a low degree. All these alleviated the membrane fouling and prolonged the membrane life. In the membrane process unit, almost all the suspended solids were captured by UF membranes, while RO membrane excluded most of the dissolved solids or inorganic salts from RO permeate. After the whole treatment processes, organic matter in POME expressed by BOD and COD was removed almost thoroughly. Suspended solids and color were not detectable in RO permeate any more, and mineral elements only existed in trace amount (except for K and Na). The high-quality effluent was crystal clear and could be used as the boiler feed water. 相似文献
1000.