Today in our environmental science lecture, we'll discuss urban heat islands. Cities tend to be warmer than surrounding rural areas because concrete and asphalt absorb and re-emit heat. However, one surprising factor is the role of green spaces. A recent study in Melbourne found that parks can reduce local temperatures by up to 4 degrees Celsius, but only if they are larger than 2 hectares. Smaller gardens have a negligible effect. Additionally, the study showed that trees along streets are more effective at cooling than grassy areas, due to shade and evapotranspiration. This has implications for city planning, especially in densely populated districts.
❓ 根据讲座内容，墨尔本的研究关于绿地发现了什么？
A. 小于2公顷的公园能显著降低温度。
B. B) 街道树木在降温方面比草地更有效。
C. C) 绿地对于城市热岛效应没有影响。
D. D) 较大的公园会使当地气温升高最多达4度。
✅ 正确答案
B) Street trees are more effective at cooling than grassy areas.