【摘要】 采用2018年敦煌莫高窟第16窟窟内与窟区PM₁₀浓度及气象数据,分析PM₁₀时空分布特征及其影响因素。结果表明:（1）两处监测点PM₁₀浓度主要分布在50μg·m^-3以下,受重污染天气影响较小;春、冬、秋、夏季依次降低,窟区PM₁₀浓度在春、冬季高于窟内,夏、秋季反之。（2）PM₁₀浓度3月最高,9月最低,5—9月窟内月均值高于窟区。PM₁₀污染日数窟内5月最多,而窟区3、5月较多。（3）PM₁₀浓度日变化曲线在春季和秋季呈"双峰"型,夏季和冬季呈"单峰"型。（4）在半封闭环境的洞窟内,沙尘暴发生前后,PM₁₀浓度达到极值及恢复至原来水平的时间均滞后于窟区。（5）在不同季节PM₁₀浓度与气温、风速和降水呈负相关。除秋季外,PM₁₀浓度与相对湿度、气压呈正相关。（6）窟区全年主风向为ESE,在冬春两季,此风向PM₁₀浓度最高,PM₁₀主要来自三危山前的戈壁滩、干涸的大泉河河道以及窟前裸露的地表积尘。更多还原

【Abstract】 The PM₁₀concentration and meteorological data in the cave 16 and the cave area of Mogao Grottoes in Dunhuang in 2018 were used to analyze the temporal and spatial distribution characteristics of PM₁₀and its in‐fluencing factors.The results show that:（1）PM₁₀concentrations at the two monitoring points are mainly distrib‐uted below 50μg·m^-3,which are less affected by heavy pollution weather.Seasonal changes from high to low are spring,winter,autumn,and summer.The PM₁₀concentration in the cave area is higher than that in the cave in spring and winter,and vice versa in summer and autumn.（2）The concentration of PM₁₀was the highest in March and the lowest in September.The monthly average value in the cave from May to September was higher than that in the cave area.The number of PM₁₀pollution days is the most in May in the caves,while March and May are more in the cave areas.（3）The diurnal variation curve of PM₁₀concentration showed a"double peak"type in spring and autumn,and a"single peak"type in summer and winter.（4）In a cave with a semi-enclosed environment,before and after a sandstorm,the time for the PM₁₀concentration to reach the extreme value and to recover to the original level lags behind the cave area.（5）PM₁₀concentration is negatively correlated with tem‐perature,wind speed and precipitation in different seasons.Except for autumn,PM₁₀concentration is positively correlated with relative humidity and air pressure.（6）The main wind direction in the cave area throughout the year is ESE.In winter and spring,PM₁₀concentration is highest in this wind direction.PM₁₀mainly comes from the Gobi Desert in front of Sanwei Mountain,the dry Daquan River channel and the exposed surface dust in front of the cave.更多还原