The coral reef (珊瑚礁) has long been a rich ecosystem in the underwater world as it provides homes [是home还是homes??] to many sea creatures. Chinese researchers recently put forward the idea of a coral reef ecological pump. It's a concept that describes how coral reefs play the role of a "pump": They gather nutrients (营养物) from different places, keep and reuse them, helping tiny plants and sea creatures grow. The study allows scientists to have a deeper understanding of the coral ecosystem.