Trees in cities play an important role in keeping a suitable temperature throughout the metropolitan area by evaporating water to provide a natural sort of air conditioning, lowering the temperatures of the air around them, and averting more than a third of the deaths that are caused by heat. Trees do this by shading people from the sun and providing shade. However, when the temperature is extremely high, trees have a difficult time surviving. A recent study came to the conclusion that simply planting trees in urban settings is not enough; trees in cities require constant maintenance.
Researchers investigated the impacts of excessive heat on trees by conducting their studies in Australia during the most recent major heatwave, which took place in 2019 and 2020. They made the discovery that certain plant species, like the red maple, that had broad leaves that were relatively thin were especially vulnerable to the impacts of the severe heat. On the other hand, plants that had thicker leaves, such as the ash and the Chinese elm, were better able to keep a steady temperature within the tree itself. The findings, which were published in the journal Global Change Biology, indicate that access to water is also highly significant. This is because trees that are adequately irrigated are able to open their pores and dissipate water, which prevents the leaves from becoming burnt.
It is anticipated that heatwaves will become more often as our climate continues to change, which will make life difficult for plants that are located in metropolitan areas. It is really important to grow tree species that can withstand high temperatures, but we also need to think of creative ways to protect our urban trees. These strategies include the use of irrigation pits, which collect and store precipitation, as well as rain gardens, which are depressions that are planted with vegetation and serve to both absorb and store runoff from flooding. Never in the history of the world has there been such an urgent need for trees.