https://online2.tingclass.net/lesson/shi0529/10000/10183/688.mp3
https://image.tingclass.net/statics/js/2012
Deep, green forests, thick with plants and ringing with the sounds of wildlife. When we think of the rain forest we usually think of abundant life. In fact, rain forests contain the world’s greatest abundance and variety of life. One research station in a Peruvian rain forest counted six hundred species of birds. That’s about as many species of birds as there are in all of North America. And the diversity of plants is even greater than it is for animals. In an area where everything grows so prolifically, you’d think a farm would also flourish. But when tropical, lowland rain forest, like what fills the Amazon basin of South America, is destroyed, the soil is generally to poor to grow anything for more than a year. One reason the rain forest soil is so poor is that most of the nutrients are stored in the plants themselves.