title: Plant uptake and in-soil degradation of PCB-5 under varying cropping conditions.
abstract: A 60-d greenhouse experiment was conducted to investigate the uptake and in-soil degradation of PCB-5 under single cropping and intercropping conditions involving three crop plant species: pumpkin, soybean and corn. Volatilization of PCB-5 from the soil surface was also tested. The results show that while uptake of PCB-5 by the test plant species is possible and the root concentration of PCB-5 had a control on the upward transport of PCB-5 to the above-ground portion of the plants, the PCB-5 extracted by the plants mainly accumulated in the root materials. Phytoextraction contributed insignificantly toward the loss of the soil-borne PCB-5. Volatilization of PCB-5 from the soil was recorded but it appeared that this did not result in a marked loss of PCB-5 in the bulk soil though it might cause remarkable removal of PCB-5 in a thin layer of the topsoil (1 mm). It is likely that the in-soil biodegradation contributed markedly to the observed reduction in soil-borne PCB-5. The in-soil biodegradation of PCB-5 was significantly enhanced under intercropping conditions, which appeared to be related to increased microbial activities, particularly bacterial activities. The soil residual PCB-5 was correlated with the activity of the following enzymes: catalase (CAT), polyphenol oxidase (PPO) and peroxidase (POD).
authors: Institute of Tropical and Subtropical Ecology, South China Agricultural University, Guangzhou 510642, China.
authors: Huashou
authors: H
authors: Li
authors: Longyuan
authors: L
authors: Liu
authors: Chuxia
authors: C
authors: Lin
authors: Shaorui
authors: S
authors: Wang
mesh_terms: D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D002374:Catalase / Q000378:metabolism; D004156:Catechol Oxidase / Q000378:metabolism; D018556:Crops, Agricultural / Q000378:metabolism*; D028464:Cucurbita / Q000378:metabolism; D005658:Fungi / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D013025:Glycine max / Q000378:metabolism; D003313:Zea mays / Q000378:metabolism
chemical_list: D012987:Soil; D012989:Soil Pollutants; D011078:Polychlorinated Biphenyls; D004156:Catechol Oxidase; D002374:Catalase; D009195:Peroxidase; C030375:2,3-dichlorobiphenyl