短时间人工沙尘覆盖对阿月浑子叶片光合和叶绿素荧光的影响

以无沙尘覆盖为对照，对阿月浑子叶片进行了人工沙尘覆盖处理试验，沙尘覆盖量分别为2，6，9，14，18rag／cra2用LI一6400光合仪测定并分析了叶片光合参数。结果表明，阿月浑子叶片短时间沙尘处理后沙尘覆盖量在2～18mg／cm2时，叶片净光合速率～直呈下降趋势，滞尘量2mg／cm2至18mg／cm。上升时叶片的净光合速率（Pn）下降幅度34％至100％；叶片的胞间C02浓度（Ci）和叶表温度则呈升高趋势，比对照分别增加80％和20％左右；气孔导度随滞尘量的增加呈下降趋势，蒸腾速率的变化趋势与气孔导度类似；沙尘覆盖对叶片的温度也有一定的影响．随着滞尘量的增加，叶片温度也增高。叶片非环式电子传递（ETR）和PSⅡ随滞尘量的增加先升高后逐渐下降趋势。

Influence of the Short time Dust Cover on Photosynthetic Rate of Pistacia vera L. Leaves and Chlorophyll Fluorescence

This experiment was carried out to analyze influence of the short time artificial dust cover on photosynthetic characteristics of Pistacia vera L. leaves, the cover with no dust was used as control.The thickness of dust were 2,6,9,14,18 mg/cm2 , respectively. Licor-6400 were used to measure and analyze photosynthetic parameters.The result showed that following the increasement of dust cover thickness from 2 mg/cm2 to 18 mg/cm2 ,net photosynthetic rate （Pn） were decreased, the biggest decrease rate was 34 -100%;the leaf intercellular CO2 concentration （Ci） and leaf temperature was increased by 80% and 20%, respectively;the change trend of stomatal conductance and transpiration rate similarly showed a de- cline current ; dust coverage has a certain influence on leaf temperature as well.The Fv/Fm values further reduced with increasing in the thickness of the dust.The PS Ⅱ and ETR were increased at first and then be- gan to decline then gradually increased in the thichness of dust between 2-18 mg/cm2.