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Major study shows climate change can cause abrupt impacts on dryland ecosystems

ScienceDaily (February 14, 2020)

Titre : Major study shows climate change can cause abrupt impacts on dryland ecosystems

Increases in aridity can damage ecosystems in areas where 2 billion people live

ScienceDaily (February 14, 2020)

Résumé
The study found for the first time that as aridity increases, dryland ecosystems undergo a series of abrupt changes. This results first in drastic reductions in the capacity of plants to fix carbon from the atmosphere, followed by substantial declines of soil fertility and ending with the disappearance of vegetation under the most arid and extreme conditions.
The key findings of the study were : * If aridity increases just a small amount of 0.5, there are rapid and often abrupt ecosystem changes * The landscape changes and is dominated by species adapted to more arid conditions and drought. * If aridity increases by 0.7, soil loses its structure and becomes more vulnerable to erosion. * Soil organisms that play essential roles in maintaining ecosystem functioning are also negatively affected. * There are large increases in the presence of pathogens at the expense of more beneficial organisms. * If aridity levels are raised beyond a threshold of 0.8, the system collapses, plants cannot thrive and the land becomes desert.
According to climatic forecasts, more than 20% of land may cross one or several of the thresholds identified in this study by 2100 due to climate change.

Story Source  : Swansea University.

Annonce (ScienceDaily)

Page publiée le 6 juin 2020