Terrestrial bryophytes were used as biomonitoring plants to investigate the status and spatial distribution pattern of heavy metal pollutions in Chengdu atmosphere in.the present study. Five species of terrestrial bryophytes were collected evenly at 15 sites within the third-ring road of Chengdu, and concentrations of seven different heavy metals were determined by ICP-AES after microwave digestion. It was showed five bryophytes had strong adsorptive ability to Pb, Cd, Cu, Zn, Cr, As and Ni, However, different terrestrial bryophytes concentrated heavy metals significantly differently among interspecies and intraspecies, with an order of Physcomitrium sphaericum (Ludw.) Fuernr. > Marchantia polymorpha L. > Taxiphyllum taxirameum(Mitt.) Fleisch. > Brachythecium moriense Besch. > Eurhynchium eustegium(Besch.)Dix. The growth environment, the structure and biological characteristics of bryophytes were probably contributed to the difference in their absorptive capacities. Intraspecies comparison showed that P. sphaericum collected in Renmin Park had the strongest absorptive ability to Cd, Zn. P. sphaericum collected in Three Holesbridge Park had the strongest absorptive ability to Cr, Ni, Cu. P. sphaericum collected in Ta Zishan Park had the weakest absorptive ability to Pb, Cd, Zn, Cr. The concentrations of Pb, Cd, Cu in M. polymorpha were the highest in Renmin Park., and the lowest in Chengdu University of Technology. T. taxirameum,collected from Xin Zhengdi Golf Club had higher concentrations of Cd, Zn, Cr, Pb than that from other sites. While the concentration of As were the hightest in Dongpo Sports Park, and the lowest in Three Holesbridge Park. Our results indicated that environment had significant influences on the absorptive ability of bryophytes to heavy metals. With respect to the pollutions of different heavy metals, Ni pollution was the most serious, Pb, Cr, Cu and As were medium, and Cd and Zn were the lightest in Chengdu. Moreover, pollutions of all heavy metals showed more seriously in centeral city, heavy traffic areas and industrial zones than that in suburban districts indicating that the heavy metal pollutions were mainly caused by vehicular traffic, smelting industry and fossil fuel combustion. The present work indicated that the pollutions of heavy metals in Chengdu atmosphere was still serious compared with a previous survey in 2005. In conclusion, our results demonstrated that P.sphaericum, M. polymorpha and T. taxirameum could be treated as efficient biomonitoring plants for monitoring the degree and district diversity of heavy metal pollutions in atmosphere.% 采用微波消解、ICP-AES对成都市一环至三环区域内15个取样点处5种地面苔藓植物体内重金属质量分数进行测定和分析，以监测和研究成都市大气沉降重金属污染状况及区域差异。结果表明：苔藓植物对重金属的富集在种间及种内差异显著，5种苔藓对Pb、Cd、Cu、Zn、Cr、As及Ni有较强的吸收能力，大小顺序为立碗藓(Physcomitrium sphaericum (Ludw.) Fuernr.)>地钱(Marchantia polymorpha L.)>鳞叶藓(Taxiphyllum taxirameum(Mitt.) Fleisch.)>柔叶青藓（Brachythecium moriense Besch.)>尖叶美喙藓（Eurhynchium eustegium（Besch.）Dix.）。对其中具有代表性的3种苔藓植物进行种内比较发现，对于立碗藓，人民公园的 Cd、Zn 质量分数最高，三洞古桥公园有最高质量分数的 Cr、Ni、Cu 及较高的 Pb，而塔子山公园的Pb、Cd、Zn、Cr及As质量分数最小；地钱对Pb、Cd、Cu、及As的积累量在人民公园达到最大，大多数重金属质量分数的最小值出现在成都理工大学；在鳞叶藓中，新阵地高尔夫俱乐部的Cd、Zn、Cr及Pb质量分数高于其余样点，东陂体育公园As质量分数最高，相反三洞古桥公园处多数重金属质量分数最小。各样点以Ni污染最重，Pb、Cr、Cu、As属污染中等，Cd和Zn污染较轻，且大气沉降重金属质量分数表现为中心城区、交通繁忙区及工业区高，郊区较低的特点。与2005年相比，成都市大气重金属污染依旧严峻，重金属质量分数呈现新的空间分布，Ni、Cr质量分数明显增加。因此，立碗藓、地钱和鳞叶藓可作为良好的生物指示植物，以此来监测成都市大气重金属污染状况。
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