Researchers find a “critical speed limit” of urban development for maintaining plant communities amid climate change.
Researchers find a “critical speed limit” of urban development for maintaining plant communities amid climate change. Most cities blow right past it.
Worsened drought stress, changing rainfall patterns, flowers and pollinators thrown out of sync: these only scratch the surface of the ways climate change challenges plant life. But warmer air and higher carbon dioxide levels can also fuel faster plant growth, limit plants’ water loss, and extend growing seasons — enough so, in some cases, to offset the paving-over of green spaces in cities.
From 1982 to now, a new study finds, cities converting more than about 5.83 square kilometers (2.25 square miles) of land to impervious surfaces within their boundaries each year tended to see the total productivity of their plant communities decline. But in slower-developing cities, the ecosystem retained its ability to recover from land conversion, with climate conditions invigorating the remaining greenery enough for overall plant productivity to rise.
The offsetting effect doesn’t apply equally in every climate. But knowing when and where it kicks in could help planners adjust the pace of development to conserve city greenery in the context of climate change, the researchers hope. Urban plants keep city air clean and cool, support city ecosystems, capture carbon dioxide and generally make cities more pleasant to live in.
Read More: American Geophysical Union
Photo Credit: BulgarianF via Pixabay
