Good morning, everyone. Today we're going to discuss the impact of climate change on agriculture. A recent study from the University of California found that warmer temperatures are causing wheat yields to drop by about 6% for every degree Celsius increase. However, the effect is not uniform. In cooler regions, like northern Europe and Canada, the longer growing season could actually boost production. Meanwhile, in tropical areas, the heat stress on crops is severe, leading to a potential 20% reduction in rice yields by 2050. Farmers are adapting by switching to drought-resistant varieties, but the cost of seeds is rising, making it difficult for small-scale farmers in developing countries.
❓ According to the lecture, what is the main effect of warmer temperatures on wheat yields?
A. A. Wheat yields increase by 6% per degree Celsius
B. B. Wheat yields decrease by about 6% per degree Celsius
C. C. Wheat yields remain unchanged
D. D. Wheat yields decrease only in tropical areas
✅ 正确答案
B. Wheat yields decrease by about 6% per degree Celsius