托福听力

🎧 听力原文

Listen to part of a lecture in an environmental science class. The professor is discussing the role of wetlands in flood control. Professor: Today, I want to talk about a natural solution to flooding that often gets overlooked: wetlands. When we think of flood prevention, we often picture concrete levees or dams, but wetlands act like natural sponges. They absorb excess rainwater, slow down the flow of water, and release it gradually over time. This reduces the peak of floodwaters downstream. For example, in the Mississippi River basin, studies have shown that restoring just a fraction of the original wetlands could significantly lower flood levels during major storms. Wetlands also trap sediment and pollutants, which improves water quality. However, despite these benefits, we have drained about half of the world's wetlands for agriculture and urban development. This has made many areas more vulnerable to flooding. So, a key question is how we can incentivize landowners to restore and preserve these vital ecosystems. One approach is through payment for ecosystem services, where governments or nonprofits compensate landowners for maintaining wetlands on their property.