Đề thi VSTEP Listening B2 — Bài giảng về Coral Bleaching (Coral san hô)

Speaker A: Good morning, everyone. Today we'll begin Module 4, which focuses on how climate change is affecting marine ecosystems. Specifically, we'll look at coral bleaching events over the past two decades. Speaker B: Professor, could you clarify something? When did scientists first observe widespread coral bleaching in this region? Speaker A: Good question. The first major bleaching event was documented in 1998, but localized cases had been recorded earlier. Since 1998, we've seen four global bleaching events. Speaker B: What makes some coral more resistant than other species? Speaker A: Certain coral species have symbiotic algae that tolerate higher temperatures. These are called thermotolerant strains, and they're the focus of current restoration projects. Speaker B: That leads to my next question — how effective are these restoration projects actually proving to be? Speaker A: Mixed results, honestly. In Australia, some reefs show recovery after five years. But in the Caribbean, restoration is much harder due to faster ocean warming. Speaker B: One last question — is there any reading we should prepare before next class? Speaker A: Yes. Please read Chapter 7 in your textbook and come prepared to discuss the case study on the Great Barrier Reef.