Carbon dioxide balance assessment of the city of Florence (Italy), and implication for urban planning

The carbon dioxide balance for the Municipality of Florence (102.3 km2), with 29.1 km2of green spacewithin the built-up city and 46.6 km2in the semi-rural peri-urban area, shows that collectively the greenspaces offset 6.2% of the direct carbon emissions. However the green spaces in the densely built-up cityonly offset 1.1% of the emissions. 13.5 ktCO2y−1are taken up by vegetation in the built-up areas and58.7 ktCO2y−1by vegetation in the peri-urban area. Urban green spaces are most efficient in offsettinganthropogenic CO2emissions during the period March to June when plant growth rates are high andemission rates are relatively low. Landscape fragmentation is highly positively correlated with totalCO2emissions and negatively correlated with CO2uptake. The detailed information produced duringthis investigation shows that policies aimed at reducing CO2emissions in winter months will have agreater overall effect on total CO2release to the atmosphere than those aimed at increasing CO2uptake.Nevertheless, urban designers should consider all the benefits of urban green spaces and seek to ensurethat new suburban development conserves green spaces and aims at sustainable urban design.