为探讨酸雨胁迫下毛竹(Phyllostachys pubescens)色素含量变化及其对光合速率和叶绿素荧光动力学参数的影响,试验模拟酸雨(SO42-∶NO3-=4∶1摩尔比),设定p H 2.5、4.0、5.6和6.9(CK),对毛竹3年生盆栽实苗进行处理,测定了叶片色素含量、...为探讨酸雨胁迫下毛竹(Phyllostachys pubescens)色素含量变化及其对光合速率和叶绿素荧光动力学参数的影响,试验模拟酸雨(SO42-∶NO3-=4∶1摩尔比),设定p H 2.5、4.0、5.6和6.9(CK),对毛竹3年生盆栽实苗进行处理,测定了叶片色素含量、净光合速率(Pn)、叶绿素荧光动力学参数并进行分析。结果表明:p H 5.6酸雨处理增加了毛竹叶片中叶绿素a(Chl a)和类胡萝卜素(Car)含量,使得光合速率(Pn)升高;p H 4.0和p H 2.5处理使Chl a、Car、Chl a+b、Chl a/b降低,Pn下降;随着处理时间延长影响效果越明显,75 d时Pn与对照(CK)相比差异极显著。p H 4.0和p H 2.5处理使荧光诱导动力学曲线的IPJ点荧光强度出现不同程度降低,处理75 d时初始荧光(F0)降低11.73%和17.59%,峰值P点荧光(Fp)降低25.46%和31.41%,反应中心密度(RC/CSo)降低22.94%和26.22%,实际量子产额(Yield)下降20.41%和35.31%、光化学淬灭系数(q P)下降15.48%和19.42%,表观光合电子传递速率(ETR)下降22.02%和25.14%,非光化学淬灭系数(q N)上升23.16%和33.46%。p H 5.6处理使荧光强度升高,F0和Fp分别比CK增加30%和18.57%,q P和ETR上升8.38%和13.53%,q N下降17.65%。酸雨胁迫使毛竹叶片天线色素吸收能量(ABS/RC)、捕获能量(TRo/RC)和热耗散能量(DIo/RC)升高;以吸收光能为基础的性能指数(PIABS)、最大光化学效率(φPo)、电子传递量子产额(φEo)、电子传递效率(ψo)和电子传递能量(ETo/RC)降低。轻度酸雨处理促进毛竹叶片光合色素合成并提高Pn,重度酸雨胁迫下光合色素含量降低,Pn下降。荧光诱导动力学曲线OJIP曲线及JIP-test分析可作为快速检测毛竹在酸雨胁迫条件下生理响应机制的方法。展开更多
A short-term exposure experiment of 19 native plant species was carried out from May 2006 to August 2008 at two sites with different stresses of acid rain pollution（HP:Guangzhou Petrochemical Factory in Huangpu repre...A short-term exposure experiment of 19 native plant species was carried out from May 2006 to August 2008 at two sites with different stresses of acid rain pollution（HP:Guangzhou Petrochemical Factory in Huangpu represents a contaminated area;LXH:Liuxihe National Forest Park represents a relative clean area）.Total 76 soil samples,collected from rhizospheres of those tested plants and the nearby bulk soil,were analyzed to investigate chemical behaviors of rhizosphere soil under the different acid rain pollution.Meanwhile,soil samples of rhizosphere of Schima superba and the nearby bulk soil under a longer-term pollution were also collected and analyzed for further confirmation.The results showed:（1）Soil major ions（H+,Al 3+,Cl-,NO3-,SO4 2-,K+,NH4+）contents in the serious acid rain stress area were higher than that in the relative clean area and the serious acid rain stress induced an increase in leaching Ca 2+,however promoted Ca 2+ transfer from bulk soil to rhizosphere soil.（2）The nutrient content of rhizosphere soil was in general higher than that of bulk soil.（3）There were antagonistic actions and negative correlations between Ca 2+（as well as organic matter）and Al 3+ in rhizosphere soil.（4）Acid rain significantly caused Al release,the ratio of exchangeable Al and exchangeable Ca（Al/Ca）of the soil in serious acid rain pollution area was larger than that in the relative clean area.（5）There was a close correlation between Al 3+ and organic acid in the soil,which suggested that the plant roots would excrete more organic acid with the enhancing acid stress for complexing Al 3+ in the root sphere to lessen the toxicity of aluminum.展开更多
文摘为探讨酸雨胁迫下毛竹(Phyllostachys pubescens)色素含量变化及其对光合速率和叶绿素荧光动力学参数的影响,试验模拟酸雨(SO42-∶NO3-=4∶1摩尔比),设定p H 2.5、4.0、5.6和6.9(CK),对毛竹3年生盆栽实苗进行处理,测定了叶片色素含量、净光合速率(Pn)、叶绿素荧光动力学参数并进行分析。结果表明:p H 5.6酸雨处理增加了毛竹叶片中叶绿素a(Chl a)和类胡萝卜素(Car)含量,使得光合速率(Pn)升高;p H 4.0和p H 2.5处理使Chl a、Car、Chl a+b、Chl a/b降低,Pn下降;随着处理时间延长影响效果越明显,75 d时Pn与对照(CK)相比差异极显著。p H 4.0和p H 2.5处理使荧光诱导动力学曲线的IPJ点荧光强度出现不同程度降低,处理75 d时初始荧光(F0)降低11.73%和17.59%,峰值P点荧光(Fp)降低25.46%和31.41%,反应中心密度(RC/CSo)降低22.94%和26.22%,实际量子产额(Yield)下降20.41%和35.31%、光化学淬灭系数(q P)下降15.48%和19.42%,表观光合电子传递速率(ETR)下降22.02%和25.14%,非光化学淬灭系数(q N)上升23.16%和33.46%。p H 5.6处理使荧光强度升高,F0和Fp分别比CK增加30%和18.57%,q P和ETR上升8.38%和13.53%,q N下降17.65%。酸雨胁迫使毛竹叶片天线色素吸收能量(ABS/RC)、捕获能量(TRo/RC)和热耗散能量(DIo/RC)升高;以吸收光能为基础的性能指数(PIABS)、最大光化学效率(φPo)、电子传递量子产额(φEo)、电子传递效率(ψo)和电子传递能量(ETo/RC)降低。轻度酸雨处理促进毛竹叶片光合色素合成并提高Pn,重度酸雨胁迫下光合色素含量降低,Pn下降。荧光诱导动力学曲线OJIP曲线及JIP-test分析可作为快速检测毛竹在酸雨胁迫条件下生理响应机制的方法。
文摘A short-term exposure experiment of 19 native plant species was carried out from May 2006 to August 2008 at two sites with different stresses of acid rain pollution（HP:Guangzhou Petrochemical Factory in Huangpu represents a contaminated area;LXH:Liuxihe National Forest Park represents a relative clean area）.Total 76 soil samples,collected from rhizospheres of those tested plants and the nearby bulk soil,were analyzed to investigate chemical behaviors of rhizosphere soil under the different acid rain pollution.Meanwhile,soil samples of rhizosphere of Schima superba and the nearby bulk soil under a longer-term pollution were also collected and analyzed for further confirmation.The results showed:（1）Soil major ions（H+,Al 3+,Cl-,NO3-,SO4 2-,K+,NH4+）contents in the serious acid rain stress area were higher than that in the relative clean area and the serious acid rain stress induced an increase in leaching Ca 2+,however promoted Ca 2+ transfer from bulk soil to rhizosphere soil.（2）The nutrient content of rhizosphere soil was in general higher than that of bulk soil.（3）There were antagonistic actions and negative correlations between Ca 2+（as well as organic matter）and Al 3+ in rhizosphere soil.（4）Acid rain significantly caused Al release,the ratio of exchangeable Al and exchangeable Ca（Al/Ca）of the soil in serious acid rain pollution area was larger than that in the relative clean area.（5）There was a close correlation between Al 3+ and organic acid in the soil,which suggested that the plant roots would excrete more organic acid with the enhancing acid stress for complexing Al 3+ in the root sphere to lessen the toxicity of aluminum.
