As ecosystems change and deserts expand, food production diminishes, water sources dry up and populations are pressured to move to more hospitable areas.

随着生态系统发生变化，沙漠面积不断扩大，粮食生产日渐减少，水源枯竭，人口也不得不迁移，搬到更适宜居住的地区。

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As ecosystems change and deserts expand, food production diminishes, water sources dry up and populations are pressured to move to more hospitable areas.

随着生态系统发生变化，沙漠面积不断扩大，粮食生产日渐减少，水源枯竭，人口也不得不迁移，搬到更适宜居住的地区。

youdao