郑州市常见公园绿化植物的滞尘能力及叶片性状分析

开展城市园林植物的滞尘研究，筛选滞尘能力强的树种对于改善城市环境具有重要意义。以郑州市10种常见的公园绿化植物为研究对象，采用滤膜过滤法测定植物叶片滞留不同粒径颗粒物（TSP、PM_>10、PM₁₀和PM_2.5）的质量，并分析叶片特征和蜡质含量对植物滞尘的影响。结果表明，不同植物叶片的滞尘能力以及滞留不同粒径颗粒物的能力均存在显著差异（P<0.05）。总体来说，滞尘能力乔木>灌木，雪松和龙柏滞留TSP和PM>10的能力最强，雪松、石楠和夹竹桃具有较强的滞留PM₁₀和PM_2.5的能力；南天竹对TSP、PM_>10、PM₁₀和PM_2.5的滞留能力均最差。叶表面形态会对滞尘能力产生影响，叶表面粗糙度较大、能分泌粘性油脂或叶脉突出的雪松、龙柏、石楠以及夹竹桃叶片滞尘能力强。叶片蜡质含量与滞尘量具有一定的相关关系，蜡质含量与PM₁₀和PM_2.5的滞尘量呈显著正相关关系，与TSP和PM_>10的相关性不显著。蜡质含量对叶片吸附细颗粒物的能力影响较大，随着蜡质含量的增加，叶片对PM₁₀和PM_2.5的滞留量增大。由此可见，叶表面形态以及叶片蜡质含量均会对植物的滞尘量产生影响，在郑州城市绿化中可以考虑雪松、龙柏和石楠等滞尘能力强的树种。

Dust-retention Capability and Leaf Traits of Common Park Greening Plant Species in Zhengzhou City

It is of great significance to study dust-retention of urban garden plant species and to select those with strong dust retention ability to improve urban environment.Ten common park greening plant species occurring in Zhengzhou city were selected to quantify particles with different sizes (TSP,PM_>10,PM₁₀,PM_2.5) per unit leaf area using a membrane filtration method.The influences of the leaf traits on dust-retention ability were analyzed.The results showed that there were significant differences in the dust retention per unit leaf area and the dust retention of different particle sizes among the 10 plant species (P<0.05).Generally,the arbor tree species had stronger dust-retention ability than shrub species.Cedrus deodara and Sabina chinensis had a strong ability to retain TSP and PM_>10 on their leaves.C.deodara,Photinia serrulata and Nerium indicum had strong ability to retain PM₁₀ and PM_2.5.Nandina domestica had the weakest ability to retain TSP,PM_>10,PM₁₀ and PM_2.5.The dust-retention ability was influenced by leaf surface morphology.The leaves of C.deodara,S.chinensis,P.serrulta and N.indicum with rough surface,sticky grease or obvious veins had strong dust-retention ability.There was correlation between the amount of dust-retention and the contents of wax from leaves.There was significant and positive correlation between the amount of PM₁₀ and PM_2.5 and the contents of wax,while there was no significant correlation between the amount of TSP and PM_>10 and the contents of wax.Wax contents had a notable influence on the dust retention ability of fine particulate matter.The ability to retain PM₁₀ and PM_2.5 increased with wax contents.Therefore,the dust-retention ability was influenced by leaf surface morphology and wax contents.C.deodara,S.chinensis and P.serrulta that had strong dust-retention ability could be considered as urban landscaping plant species in Zhengzhou city.