【英语时差8,16】伐木致热带雨林土壤贫瘠（下）

In any forest, dead organic matter falls to the ground, providing valuable nutrients¹ for new growth. In cooler or drier climates, the nutrients build up in the soil. But in a rain forest, with its abundance and variety of life, those nutrients are reabsorbed almost as fast as they’re deposited. Also, the trees in tropical rain forests are often evergreens² and so very few leaves actually fall to the ground. When a rain forest is burned to raise crops or cattle, most of the nutrients are destroyed along with the vegetation. Grass may grow for a year, but as the grass is turned into beef, the few remaining nutrients are depleted³. Since land in the rain forest is often cheaper than fertilizer, farmers often clear new fields each year, leaving the old ones to turn into desert.

1 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

2 evergreens   

n.常青树，常绿植物，万年青( evergreen的名词复数 )

参考例句：

• The leaves of evergreens are often shaped like needles. 常绿植物的叶常是针形的。 来自《简明英汉词典》
• The pine, cedar and spruce are evergreens. 松树、雪松、云杉都是常绿的树。 来自辞典例句

3 depleted   

adj. 枯竭的, 废弃的 动词deplete的过去式和过去分词

参考例句：

• Food supplies were severely depleted. 食物供应已严重不足。
• Both teams were severely depleted by injuries. 两个队都因队员受伤而实力大减。