• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Chlorophyll fluorescence as a mechanistic bioindicator of photosynthetic inhibition in aquatic plants.
【24h】

Chlorophyll fluorescence as a mechanistic bioindicator of photosynthetic inhibition in aquatic plants.

机译：叶绿素荧光是水生植物光合作用抑制的机制生物指示剂。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This thesis describes an investigation of a chlorophyll fluorescence assay used to estimate the efficiency of photosynthetic electron transport in plants exposed to environmental stress from polycyclic aromatic hydrocarbons (PAHs) and solar ultraviolet radiation. A series of experiments were performed to validate pulse amplitude modulated chlorophyll fluorescence in aquatic plants as a rapid biological indicator of exposure to environmental contaminants and stressors. Chlorophyll fluorescence endpoints were measured in the macrophytes Lemna gibba and Myriophyllum spicatum upon exposure to creosote, a mixture of polycyclic aromatic hydrocarbons. In laboratory exposures, the concentration-dependent response of chlorophyll fluorescence was closely related to conventional endpoints such as frond production, shoot length, root length and leaf chlorophyll concentration. Chlorophyll fluorescence was similarly diminished in plants exposed to creosote in outdoor aquatic microcosms, at concentrations which inhibited seasonal plant population biomass. Chlorophyll fluorescence was therefore predictive of effects at higher levels of biological organization. To examine the applicability of this assay in the field, chlorophyll fluorescence was measured from natural assemblages of Lake Erie phytoplankton exposed to the PAHs anthracene and 1,2-dihydroxyanthraquinone. It was found that inhibition of photosynthetic electron transport could be detected with short exposures to low chemical concentrations.; The ability of chlorophyll fluorescence to detect inhibition of photosynthesis by sunlight (photoinhibition) was examined in Myriophyllum plants in microcosms screened to remove specific wavelengths of sunlight. The ultraviolet-B, ultraviolet-A and visible regions of sunlight had specific but minor effects on the various chlorophyll fluorescence parameters. No clear relationship between chlorophyll fluorescence and plant growth was found. However, when chlorophyll fluorescence was examined in Lake Erie phytoplankton exposed to the same sunlight treatments, a rapid and dose-dependent effect was observed. A nonlinear statistical model based on the cumulative energy received by the phytoplankton was used to estimate biological effectiveness coefficients for photoinhibition by each waveband. It was found that ultraviolet-B radiation was much more damaging than other wavelengths of sunlight. Chlorophyll fluorescence is therefore a suitable endpoint for detecting inhibition of photosynthetic electron transport in aquatic plants exposed to various environmental stresses, which is linked to effects at higher levels of biological organization.
机译：本论文描述了叶绿素荧光测定法的研究，该测定法用于估计暴露于多环芳烃（PAHs）和太阳紫外线辐射的环境胁迫下的植物中光合作用电子的运输效率。进行了一系列实验，以验证水生植物中脉冲幅度调制的叶绿素荧光作为暴露于环境污染物和应激源的快速生物学指标。暴露于杂多酚（一种多环芳香烃混合物）后，在大型植物 Lemna gibba 和 Myriophyllum spicatum 中测定了叶绿素荧光终点。在实验室暴露中，叶绿素荧光的浓度依赖性响应与常规终点密切相关，例如叶绿素生成，枝条长度，根长和叶绿素浓度。类似地，在室外水生微观世界中，暴露于杂酚油的植物中的叶绿素荧光也降低了，其浓度抑制了季节性植物种群生物量。因此，叶绿素荧光可预测在更高水平的生物组织中的作用。为了检查该测定法在野外的适用性，从暴露于PAHs蒽和1,2-二羟基蒽醌的伊利湖浮游植物的天然组合物中测量了叶绿素荧光。发现在短时间暴露于低化学浓度下可以检测到光合电子传输的抑制。在筛选去除了特定波长的阳光的微观世界中，检验了 Myriophyllum 植物中叶绿素荧光检测日光对光合作用的抑制（光抑制）的能力。紫外线的B，紫外线A和可见光区域对各种叶绿素荧光参数具有特定但较小的影响。叶绿素荧光与植物生长之间没有明确的关系。但是，在暴露于相同日光处理的伊利湖浮游植物中检查叶绿素荧光时，观察到了快速且剂量依赖性的效应。基于浮游植物所接收的累积能量的非线性统计模型用于估计每个波段对光抑制的生物有效性系数。发现紫外线B辐射比其他波长的太阳光更具破坏性。因此，叶绿素荧光是检测暴露于各种环境胁迫的水生植物中光合作用电子的抑制作用的合适终点，这与更高水平的生物组织作用有关。

著录项

  • 作者

    Marwood, Christopher Andrew.;

  • 作者单位

    University of Guelph (Canada).;

  • 授予单位 University of Guelph (Canada).;
  • 学科 Environmental Sciences.; Biology Botany.
  • 学位 Ph.D.
  • 年度 1999
  • 页码 288 p.
  • 总页数 288
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 环境科学基础理论;植物学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号