Others are political;the pumps and aqueducts that carry water from the wetter north to the dry fields in the south are creaking with age, threatening ecosystems and endangering species.

• 也有政治原因：从湿润的北部地区输水到干旱的南部地区的泵和输水管道由于年深日久，勉强地运转着，危及这里的生态系统和物种。