无锡市国控环境空气自动监测站点周边裸土分布高分辨率遥感监测

以无锡市为研究区,使用过境时间相近的哨兵2号Sentinel-2和Landsat8影像,综合使用NDSI、NDISI、MNDWI、LST等指数进行决策树分类,获得10 m高空间分辨率的土地利用分类结果和裸土分布,裸土提取精度达到94.13%。统计了无锡市与8个国控环境空气自动监测站点1、2、3 km缓冲区范围内的裸土分布情况,并与各站点监测的大气颗粒物浓度进行相关性分析。结果表明,国控环境空气自动监测站点周边裸土面积对颗粒物浓度有较大影响,其中对PM₁₀浓度的影响明显大于PM_2.5;相比于1 km和3 km,2 km缓冲区范围内的裸土面积对PM₁₀浓度的影响最大,建议环境管理部门重点关注无锡地区国控监测站点周边2 km范围内的裸土扬尘源分布情况。

High-Resolution Remote Sensing Monitoring of the Distribution of Bare Soil Around the National Controlled Ambient Air Automatic Monitoring Station in Wuxi City

Taking Wuxi City as the study area,the decision tree classification was carried out using Sentinel-2 and Landsat8 satellite remote sensing images with similar transit time,and a combination of NDSI,NDISI,MNDWI and LST indices was used to obtain 10m high spatial resolution land use classification results and bare soil distribution,with bare soil extraction accuracy reaching 94.13%.The distribution of bare soil within the 1km,2km and 3km buffer zones of eight state-controlled automatic ambient air monitoring stations in Wuxi were counted and correlated with the atmospheric particulate matter concentrations monitored at each station.The results showed that the area of bare soil around the state-controlled automatic ambient air monitoring stations had a greater influence on the concentration of particulate matter,with a significantly greater influence on PM₁₀ concentrations than PM_2.5.Compared with 1 km and 3 km,the area of bare soil within the 2 km buffer zone had the greatest influence on PM₁₀ concentrations,suggesting that environmental management departments should focus on the distribution of bare soil and dust sources within the 2 km range around the state-controlled monitoring stations in Wuxi.