Farming Techniques Must Improve to Counter Increasingly Warmer Summers
Global climate change is causing average temperatures to rise and producing more extreme highs during the summer months, months that are crucial for a successful crop yield. According to a new study from the University of Leeds, Reading, and Exeter, hotter summers may cause a decrease in crop yields over the next two decades. The only thing that can prevent it will be to improve farming techniques to counter the trend.
The damaging effect of hotter summers was examined in France, a largely agrarian country and breadbasket for much of Europe including Great Britain. The warmer temperatures have already caused a slowdown in the trend towards higher yields of maize (sweetcorn).
Agricultural improvements that will be necessary include improved fertilizers, heat and drought resistant crop varieties, and irrigation techniques. These improvements will be necessary to offset the 12% decrease in crop yield that is expected from future heat stress.
The researchers worry that the current rate of improvement will not meet this target. According to Dr. Ed Hawkins of the National Centre for Atmospheric Science at the University of Reading, "Our research rings alarm bells for future food security. Over the last 50 years, developments in agriculture, such as fertilisers and irrigation, have increased yields of the world's staple foods, but we're starting to see a slowdown in yield increases. Our research into maize suggests the increasing frequency of hot days across the world might explain some of this slowdown.
"We expect hot days to become more frequent still, and our work on maize suggests that current advances in agriculture are too slow to offset the expected damage to crops from heat stress in the future."
Their study of maize in France revealed that the crop has become less sensitive to rain quantity over the summer, and relatively more sensitive to temperature over the last 50 years. Less rain can be offset by more irrigation, but there is no way to offset higher temperatures.
Over the last 50 years, days with temperatures above 32 degrees C (90 F) have doubled in France. By 2020, hot days like this will occur over large parts of the country, and grow more common. That is why there must be emphasis on improving farming techniques to withstand the changing climate.
This study has been published in the journal Global Change Biology
French Farmland image via Shutterstock