Denser and greener cities

Green spaces in urban areas-- like remnant habitat, parks, constructed wetlands, and street trees-- supply multiple benefits. Many studies show green spaces in and near urban areas play important roles harboring biodiversity and promoting human well-being. On the other hand, evidence suggests that greater human population density enables compact, low-carbon cities that spare habitat conversion at the fringes of expanding urban areas, while also allowing more walkable and livable cities. How then can urban areas have abundant green spaces as well as density?  
This data archive contains data created as part of a scientific manuscript that attempts to answer this question, entitled \"Denser and greener cities: Green interventions to achieve both urban density and nature\". Please see that manuscript for details on sources of data and details of methodology.
We found that there is a negative correlation between population density and urban green spaces. For Functional Urban Areas in the OECD..., Please see the Methods section in McDonald et al. (People and Nature) for details on our methods., All data tables are provided as CSV files, which can be read by a number of proprietary (e.g., Excel) and open-source (e.g., LibreOffice) software packages.