การฟัง TOEFL

🎧 บทถอดเสียง

Listen to part of a lecture in an environmental science class. Professor: Today we're going to talk about a surprising ally in the fight against climate change: beavers. You might think of beavers as simple dam builders, but their activities have profound effects on local ecosystems. When beavers build dams, they create ponds, which slow down water flow. This allows sediment and pollutants to settle, naturally purifying the water. Moreover, these ponds provide habitat for fish, amphibians, and birds, increasing biodiversity. But there's more. The dams also help to store carbon. The flooded areas become oxygen-poor, which slows down the decomposition of organic matter, trapping carbon in the soil for centuries. In fact, research shows that beaver ponds can sequester up to 30 times more carbon than a similar area without them. So, by reintroducing beavers to degraded river systems, we might be able to restore wetlands and combat climate change simultaneously. However, beaver activity can also cause conflicts with human land use, such as flooding roads or timberlands. Therefore, careful management is needed.