Today in our environmental science lecture, we'll discuss urban green spaces. A recent study in Melbourne found that parks can reduce local temperatures by up to 4 degrees Celsius during heatwaves. However, the cooling effect depends on tree canopy coverage; areas with less than 30% canopy showed minimal benefit. Interestingly, the study also noted that residents living within 500 meters of a large park reported better mental health, but only if the park had water features or dense vegetation. So, while small grassy areas are pleasant, they don't provide the same climate regulation or psychological benefits.
❓ According to the lecture, what condition is necessary for a park to have a significant cooling effect?
A. A. It must be within 500 meters of residential areas.
B. B. It should have at least 30% tree canopy coverage.
C. C. It needs to include water features.
D. D. It must be a large park with dense vegetation.
✅ 正确答案
B. It should have at least 30% tree canopy coverage.