他们发现，20世纪80年代之前的产量增长速度在20世纪90年代和21世纪有所放缓，这占据了作物收割面积的24%至39%。
They find that on between 24% and 39% of all harvested areas, the improvement in yields that took place before the 1980s slowed down in the 1990s and 2000s.
沙漠已经占据了大约四分之一的地球表面积，近几十年来还在一直以惊人的速度增加。
The deserts, which already occupy approximately a fourth of the Earth's land surface, have in recent decades been increasing at an alarming pace.
西方森林面积的快速增长似乎同其他各地的森林开采速度一样不可阻挡。
The growth of Western forests seems almost as unstoppable as deforestation elsewhere.
应用推荐