雅思听力

🎧 Listening Transcript

Today in our environmental science lecture, we're discussing urban green spaces. A recent study in Melbourne tracked the effects of adding rooftop gardens to city buildings. The researchers measured temperature, air quality, and biodiversity over two years. They found that rooftop gardens reduced local temperatures by up to 3 degrees Celsius in summer, but only when the gardens covered at least 60% of the roof area. Additionally, bird species increased by 15% in areas within 500 meters of these gardens. However, the study noted that maintenance costs were higher than expected, mainly due to irrigation needs. The key takeaway is that green roofs require careful planning to maximize benefits.