青岛市3种常绿灌木滞尘量与叶微观特征及光合作用等的相关性分析OA北大核心CSTPCD

Taking three common evergreen shrubs in Chengyang District,Qingdao City as the research ob-jects,the mass of particulate matter(TSP,PM＞10,PM10,PM2.5)retained per unit leaf area of each shrub was measured using a three-stage membrane filtration method.The leaf surface micromorphological char-acteristics of the three evergreen shrubs were observed and compared under scanning electron microscopy,and the correlations between leaf microstructure,chlorophyll fluorescence parameters,gas exchange param-eters,and plant dust retention were analyzed.The dust retention capacity per unit leaf area of the leaves of the three shrubs was as follows:Pyracantha fortuneana＞Buxus sinica＞Ligustrum quihoui.Scanning the microstructure of the leaf surface with an electron microscope showed that the leaf surface was rough,with a dense and undulating distribution of stomata in the lower epidermis.Plants with irregular striped and fur-rowed tissue were conducive to the attachment of particles.Principal component analysis found that the TSP per unit leaf area of the three shrubs only showed a positive correlation with the width of the grooves in the lower epidermis of the plant,and there was no significant correlation with other indicators.The chlo-rophyll content,maximum photochemical efficiency(Fv/Fm),and photochemical quenching coefficient(qP)of the leaves of the three shrubs after dust retention were significantly lower than those before dust retention,while the non photochemical quenching coefficient(NPQ)was significantly higher than those be-fore dust retention.In addition,there were significant differences in the net photosynthetic rate(Pn),tran-spiration rate(Tr),stomatal conductance(Gs),and intercellular CO2 concentration(Ci)of the leaves of the three shrubs.Compared with those before dust retention,the Pn,Tr,and Gs of the three shrubs after dust retention decreased by 27.1％,44.2％,7.1％,7.9％,38.3％,19.7％,and 38.0％,38.7％,11.6％,and Ci increased by 8.2％,5.1％,and 4.9％,respectively.The principal component analysis showed that the TSP and chlorophyll content per unit leaf area of the three shrubs Fv/Fm and Pn had a significant or ex-tremely significant negative correlation,and a significant positive correlation with Ci.The conclusion is that leaf surface roughness,number and size of stomata,and groove width affect the dust retention ability of plants,and dust retention have a certain degree of impact on chlorophyll and chlorophyll fluorescence pa-rameters of plant leaves,reducing photosynthesis of plant leaves.P.fortunei can be considered as a shrub species with strong dust retention ability.