Larson Timothy, Su Jason, Baribeau Anne-Marie, Buzzelli Michael, Setton Eleanor, Brauer Michael
Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA.
Environ Sci Technol. 2007 Apr 1;41(7):2429-36. doi: 10.1021/es0614060.
In many urban areas, residential wood burning is a significant wintertime source of PM2.5. In this study, we used a combination of fixed and mobile monitoring along with a novel spatial buffering procedure to estimate the spatial patterns of woodsmoke. Two-week average PM2.5 and levoglucosan (a marker for wood smoke) concentrations were concurrently measured at upto seven sites in the study region. In addition, pre-selected routes spanning the major population areas in and around Vancouver, B.C. were traversed during 19 cold, clear winter evenings from November, 2004 to March, 2005 by a vehicle equipped with GPS receiver and a nephelometer. Fifteen-second-average values of light scattering coefficient (bsp) were adjusted for variations between evenings and then combined into a single, highly resolved map of nighttime winter bsp levels. A relatively simple but robust (R(2) = 0.64) land use regression model was developed using selected spatial covariates to predict these temporally adjusted bsp values. The bsp values predicted by this model were also correlated with the measured average levoglucosan concentrations at our fixed site locations (R(2) = 0.66). This model, the first application of land use regression for woodsmoke, enabled the identification and prediction of previously unrecognized high woodsmoke regions within an urban airshed.
在许多城市地区，冬季居民燃烧木材是细颗粒物（PM2.5）的一个重要来源。在本研究中，我们结合了固定监测和移动监测，并采用一种新颖的空间缓冲程序来估算木烟的空间分布模式。在研究区域内多达7个地点同时测量了为期两周的PM2.5平均浓度和左旋葡聚糖（一种木烟标志物）浓度。此外，在2004年11月至2005年3月期间的19个寒冷晴朗的冬夜，一辆配备了全球定位系统接收器和浊度仪的车辆沿着预先选定的路线穿越了不列颠哥伦比亚省温哥华市及其周边的主要人口区域。对光散射系数（bsp）的15秒平均值进行了夜间差异调整，然后合并成一张分辨率很高的夜间冬季bsp水平图。利用选定的空间协变量建立了一个相对简单但稳健（R² = 0.64）的土地利用回归模型，以预测这些经过时间调整的bsp值。该模型预测的bsp值也与我们固定站点位置测量的平均左旋葡聚糖浓度相关（R² = 0.66）。这个模型是土地利用回归在木烟研究中的首次应用，能够识别和预测城市空气流域内以前未被认识到的高木烟区域。
