大金发藓对土壤多氯联苯污染的生理生态响应  

Eco-physiological responses of Polytrichum commune to soil contamination by polychlorinated biphenyls

作　　者：吴启美[1] 周启星[1] 

机构地区：[1]南开大学环境科学与工程学院、环境污染过程与基准教育部重点实验室、天津市城市生态修复与污染防治重点实验室,天津300071

出　　处：《植物生态学报》2015年第3期275-282,共8页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金委员会-广东省人民政府联合基金重点项目(U1133006);国家自然科学基金面上项目(31170473);国家高技术研究发展计划(863计划)项目(2012AA101403-2)

摘　　要：通过微体繁殖技术在多氯联苯(PCBs)污染土壤基质上进行大金发藓(Polytrichum commune)的室内培养,研究了不同浓度(5、10和20 mg·kg–1)低氯PCBs(Aroclor 1242)和高氯PCBs(Aroclor 1254)对大金发藓生理生态指标的影响。经6个月的培养,大金发藓的密度和盖度分别达93%和50株·cm–2以上,PCBs处理组与对照组相比无显著差异,表明PCBs对大金发藓茎叶碎片再生成新植株体的能力没有产生不利影响。大金发藓鲜质量和株高随低氯PCBs(Aroclor 1242)浓度增加而增加、随高氯PCBs(Aroclor 1254)浓度增加而减小,但均高于对照,表明PCBs处理对大金发藓的生长具有一定的促进作用。PCBs处理组大金发藓叶绿素a、b以及叶绿素a+b含量较对照组有所增加,叶绿素a/b值与对照组相比基本没有变化。PCBs处理组大金发藓膜脂过氧化产物丙二醛含量和超氧化物歧化酶活性与对照组相比无显著差异,谷胱甘肽含量较对照组显著增加,表明谷胱甘肽在大金发藓体内活性氧清除过程中起重要作用。总体来看,大金发藓能在所设浓度的PCBs范围内正常生长,对PCBs有较强的耐性。Aims The objective of this study was to investigate the tolerance of Polytrichum commune to soil contamination by polychlorinated biphenyls（PCBs）, and the underlying eco-physiological mechanisms. Methods Polytrichum commune was propagated and cultured in PCBs contaminated soil by means of micropropagation under laboratory conditions, and eco-physiological variables relating to tolerance to PCBs（Aroclor 1242 and Aroclor 1254） contamination were studied. Important findings The coverage and density of P. commune were higher than 93% and 50 plants·cm–2 and there was no significant difference between the PCBs treatments and the control. PCBs（Aroclor 1242 and Aroclor 1254） had no adverse effects on the regeneration of gametophyte fragments. The height and fresh mass of P. commune increased with an increase in the concentration of Aroclor 1242, and decreased with an increase in the concentration of Aroclor 1254, but they were higher in the PCBs treatment than in the control, indicating that PCBs stimulated the growth of P. commune. The contents of chlorophyll（Chl） a, Chl b and Chl a ＋ b in P. commune were slight higher in the PCBs treatments than in the control, and the ratio of Chl a/b maintained relatively stable in both the PCBs treatments and the control. The content of malondialdehyde and activity of superoxide dismutase in P. commune were not significantly different between the PCBs treatments and the control, whereas the content of glutathione was significantly higher in the PCBs treatments than in the control, indicating that glutathione played a pivotal role in the course of scavenging reactive oxygen species. The study demonstrated that the growth of P. commune was not adversely impacted by PCBs contaminated soil at given concentrations, reflecting its tolerance to PCBs.

关 键 词：生理生态响应 污染 多氯联苯 大金发藓 

分 类 号：X53[环境科学与工程—环境工程]