Wu Jiansheng, Xie Wudan, Li Weifeng, Li Jiacheng
The Key Laboratory for Environmental and Urban Sciences, School of Urban Planning and Design, Peking University Shenzhen, Shenzhen, China.
College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes, Ministry of Education, Peking University, Beijing, China.
PLoS One. 2015 Nov 13;10(11):e0142449. doi: 10.1371/journal.pone.0142449. eCollection 2015.
PM2.5 refers to particulate matter (PM) in air that is less than 2.5 μm in aerodynamic diameter, which has negative effects on air quality and human health. PM2.5 is the main pollutant source in haze occurring in Beijing, and it also has caused many problems in other cities. Previous studies have focused mostly on the relationship between land use and air quality, but less research has specifically explored the effects of urban landscape patterns on PM2.5. This study considered the rapidly growing and heavily polluted Beijing, China. To better understand the impact of urban landscape pattern on PM2.5 pollution, five landscape metrics including PLAND, PD, ED, SHEI, and CONTAG were applied in the study. Further, other data, such as street networks, population density, and elevation considered as factors influencing PM2.5, were obtained through RS and GIS. By means of correlation analysis and stepwise multiple regression, the effects of landscape pattern on PM2.5 concentration was explored. The results showed that (1) at class-level, vegetation and water were significant landscape components in reducing PM2.5 concentration, while cropland played a special role in PM2.5 concentration; (2) landscape configuration (ED and PD) features at class-level had obvious effects on particulate matter; and (3) at the landscape-level, the evenness (SHEI) and fragmentation (CONTAG) of the whole landscape related closely with PM2.5 concentration. Results of this study could expand our understanding of the role of urban landscape pattern on PM2.5 and provide useful information for urban planning.
细颗粒物(PM2.5)是指空气动力学直径小于2.5微米的大气颗粒物,它会对空气质量和人体健康产生负面影响。PM2.5是北京雾霾天气的主要污染源,在其他城市也引发了诸多问题。以往的研究大多聚焦于土地利用与空气质量之间的关系,但专门探讨城市景观格局对PM2.5影响的研究较少。本研究以快速发展且污染严重的中国北京为研究对象。为了更好地理解城市景观格局对PM2.5污染的影响,本研究应用了包括斑块面积比例(PLAND)、斑块密度(PD)、边缘密度(ED)、景观形状指数(SHEI)和蔓延度指数(CONTAG)在内的五个景观指标。此外,通过遥感(RS)和地理信息系统(GIS)获取了街道网络、人口密度和海拔等其他被视为影响PM2.5的因素的数据。通过相关性分析和逐步多元回归,探讨了景观格局对PM2.5浓度的影响。结果表明:(1)在斑块类型水平上,植被和水体是降低PM2.5浓度的重要景观组分,而农田在PM2.5浓度方面发挥着特殊作用;(2)斑块类型水平上的景观构型(边缘密度和斑块密度)特征对颗粒物有显著影响;(3)在景观水平上,整个景观的均匀度(景观形状指数)和破碎度(蔓延度指数)与PM2.5浓度密切相关。本研究结果能够拓展我们对城市景观格局在PM2.5方面作用的认识,并为城市规划提供有用信息。