Heat threatens native biodiversity in Belgian countryside

New research by the universities of Liège and Antwerp shows that heat is threatening native biodiversity in the Belgian countryside. "Exotic plants are escaping from the city to the countryside", the scientists stated in a press release on Monday.

Belgian cities harbour different alien plant species than the cooler countryside. But "summers like today's might cause those species to dominate everywhere", the researchers fear.

"Hot air envelops cities like a blanket on hot days", explains Jonas Lembrechts (Antwerp University). "Moreover, the soil in the city is often drier than in the surrounding countryside. More water runs off and the extra heat causes faster evaporation. So, until recently, trees of warmer origins were necessarily confined to the city because the climatic conditions in the countryside were simply not suitable. Now that summers are becoming drier and warmer, and our winters are no longer so cold, the right conditions for their development are expanding."

Therefore, it is increasingly likely for urban exotics, such as the so-called 'tree of heaven' (native to China, Taiwan and Korea) or the North American 'princess tree', to spread throughout the Belgian countryside. This spread could happen at the expense of indigenous biodiversity, which is already weakened by droughts and heatwaves.

(BRV)

© BELGA PHOTO BRUNO FAHY