A co-culture of two plant materials, Astragalus sinicus L., a leguminous plant with concomitant nodules, and Elsholtzia splendens Naki-a Cu accumulator, along with treatments of a chelating agent (EDTA), root excretio...A co-culture of two plant materials, Astragalus sinicus L., a leguminous plant with concomitant nodules, and Elsholtzia splendens Naki-a Cu accumulator, along with treatments of a chelating agent (EDTA), root excretions (citric acid), and a control with E. splendens only were used to compare the mobility of heavy metals in chelating agents with a co-culture and to determine the potential for co-culture phytoremediation in heavy metal contaminated soils. The root uptake for Cu, Zn, and Pb in all treatments was significantly greater (P ＜ 0.05) than that of the control treatment. However with translocation in the shoots, only Cu, Zn, and Pb in plants grown with the EDTA treatment and Zn in plants cocropped with the A. sinicus treatment increased significantly (P ＜ 0.05). In addition, when a co-culture in soils with heavy and moderate contamination was compared, for roots in moderately contaminated soils only Zn concentration was significantly less (P ＜ 0.05) than that of heavily contaminated soils, however, Cu, Zn, and Pb concentrations of shoots were all significantly lower (P ＜ 0.05). Overall, this 'co-culture engineering' could be as effective as or even more effective than chelating agents, thereby preventing plant metal toxicity and metal leaching in soils as was usually observed in chelate-enhanced phytoremediation.展开更多
An advanced sludge reduction process, i.e. sludge reduction and phosphorous removal process, was developed. The results show that excellent sludge reduction and biological phosphorous removal can be achieved perfectly...An advanced sludge reduction process, i.e. sludge reduction and phosphorous removal process, was developed. The results show that excellent sludge reduction and biological phosphorous removal can be achieved perfectly in this system. When chemical oxygen demand ρ（COD） is 332 - 420 mg/L, concentration of ammonia p（NH3-N） is 30 - 40 mg/L and concentration of total phosphorous p（TP） is 6.0 -9.0 mg/L in influent, the system still ensures ρ（COD）〈23 mg/L, ρ（NH3-N）〈3.2 mg/L and ρ（TP）〈0. 72 mg/L in effluent. Besides, when the concentration of dissolved oxygen ρ（DO） is around 1.0 mg/L, sludge production is less than 0. 140 g with the consumption of 1 g COD, and the phosphorous removal exceeds 91 %. Also, 48.4% of total nitrogen is removed by simultaneous nitrification and denitrification.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 40271060 and 41025005) the National Key Basic Research Support Foundation (NKBRSF) of China (No. 2002CB410809/10).
文摘A co-culture of two plant materials, Astragalus sinicus L., a leguminous plant with concomitant nodules, and Elsholtzia splendens Naki-a Cu accumulator, along with treatments of a chelating agent (EDTA), root excretions (citric acid), and a control with E. splendens only were used to compare the mobility of heavy metals in chelating agents with a co-culture and to determine the potential for co-culture phytoremediation in heavy metal contaminated soils. The root uptake for Cu, Zn, and Pb in all treatments was significantly greater (P ＜ 0.05) than that of the control treatment. However with translocation in the shoots, only Cu, Zn, and Pb in plants grown with the EDTA treatment and Zn in plants cocropped with the A. sinicus treatment increased significantly (P ＜ 0.05). In addition, when a co-culture in soils with heavy and moderate contamination was compared, for roots in moderately contaminated soils only Zn concentration was significantly less (P ＜ 0.05) than that of heavily contaminated soils, however, Cu, Zn, and Pb concentrations of shoots were all significantly lower (P ＜ 0.05). Overall, this 'co-culture engineering' could be as effective as or even more effective than chelating agents, thereby preventing plant metal toxicity and metal leaching in soils as was usually observed in chelate-enhanced phytoremediation.
基金Project (50278101) supported by the National Natural Science Foundation of China Project( CSTC, 2005AB7030)supported by Chongqing Key Technologies Research and Development Program
文摘An advanced sludge reduction process, i.e. sludge reduction and phosphorous removal process, was developed. The results show that excellent sludge reduction and biological phosphorous removal can be achieved perfectly in this system. When chemical oxygen demand ρ（COD） is 332 - 420 mg/L, concentration of ammonia p（NH3-N） is 30 - 40 mg/L and concentration of total phosphorous p（TP） is 6.0 -9.0 mg/L in influent, the system still ensures ρ（COD）〈23 mg/L, ρ（NH3-N）〈3.2 mg/L and ρ（TP）〈0. 72 mg/L in effluent. Besides, when the concentration of dissolved oxygen ρ（DO） is around 1.0 mg/L, sludge production is less than 0. 140 g with the consumption of 1 g COD, and the phosphorous removal exceeds 91 %. Also, 48.4% of total nitrogen is removed by simultaneous nitrification and denitrification.
