Journal Article
The role of spatial representation in the development of a LUR model for Ottawa, Canada
Parenteau, MP; Sawada, MC
Air Quality, Atmosphere and Health
ISSN: 1873-9318
EISSN: 1873-9326
A land use regression (LUR) model for the mapping of NO(2) concentrations in Ottawa, Canada was created based on data from 29 passive air quality samplers from the City of Ottawa's National Capital Air Quality Mapping Project and two permanent stations. Model sensitivity was assessed against three spatial representations of population: population at the dissemination area level, population at the dissemination block level and a dasymetrically derived population representation. A spatial database with land use, roads, population, zoning, greenspaces and elevation was created. Polycategorical zoning data were used in dasymetric mapping to spatially focus population data derived from the dissemination blocks to a sub-block level for comparison purposes. Dasymetric population mapping provided no significant LUR model improvement in explained variance when compared to block level population; however, both the former were significantly better than the dissemination area level population representations. However, where block level population is not available or too costly to acquire, our method using polycategorical zoning data provides a viable alternative in LUR modelling endeavours.
GIS, LUR, Dasymetric mapping, Scale LUR, Land use regression; NO2, Nitrogen dioxide; DA, Dissemination area; DISB, Dissemination block; CMA, Census Metropolitan Area; GIS, Geographical Information System; PDF, Population density fraction; AR, Area ratio; TF, Total fraction; RMSE, Root-mean-square error; VIF, Variation inflation factor; CI, Condition index; LOOCV, Leave-one-out cross-validation; MAE, Mean absolute error