The Impact of Increased Frequency of Extreme Droughts on Crop Production
With the ongoing climate change, the world is experiencing more frequent extreme weather events. Research scientist Pål Thorvaldsen, from NIBIO, took part in a global drought experiment led by the University of Michigan, U.S. This study revealed that short-term extreme droughts, which used to happen once every 100 years, may now occur every five to 10 years as per current climate projections.
The research focused on grass- and shrub-dominated ecosystems, essential for livestock grazing. The findings showed a staggering 60% drop in plant growth in grasslands during short-term extreme droughts compared to moderate drought conditions. This decline raises concerns about food production sustainability in these critical ecosystems.
Examining 170 sites worldwide, the scientists noted a significant reduction of almost 40% in plant biomass in grass-dominated areas after just one year of extreme drought. The shrub-dominated ecosystems saw a 20% decrease. This emphasizes the importance of maintaining pastures to prevent drying out, particularly for farmers relying on them for animal husbandry.
Adding shrubs or trees in pastures can create a beneficial microclimate that mitigates the impact of extreme drought. While simultaneous extreme droughts across Norway are rare, ensuring access to watering systems could become crucial for securing the food supply in the future.
Coastal heathlands in Norway, dominated by heather, have shown resilience to drought conditions. These ecosystems cover 30-40% of the Earth’s surface and play a significant role in carbon storage. Reduced plant production affects the carbon cycle by decreasing CO2 absorption from the atmosphere, underscoring the importance of understanding how plants respond to climate change.
Norwegian researchers studied six coastal heathland sites across the country, highlighting the need to preserve these areas for both global food production and climate stability. Their findings emphasize the urgency of addressing the challenges posed by more frequent extreme droughts to ensure sustainable agriculture practices and environmental health.