More than half of the world's largest lakes and reservoirs are dwindling and placing humanity's future water security at risk, with climate change and unsustainable consumption the main culprits, a study said Thursday.

周四的一项研究表明，世界上一半以上的最大湖泊和水库正在萎缩，并将人类未来的水安全置于危险之中，气候变化和不可持续的消费是罪魁祸首。

"Lakes are in trouble globally, and it has implications far and wide," Balaji Rajagopalan, a professor at the University of Colorado Boulder and co-author of the paper, which appeared in Science, told AFP.

科罗拉多大学博尔德分校教授巴拉吉·拉贾戈帕兰是该论文的合著者，该论文发表在《科学》杂志上，他告诉法新社:“全球湖泊都陷入了困境，这一问题影响深远。”

"It really caught our attention that 25 percent of the world's population is living in a lake basin that is on a declining trend," he continued, meaning some two billion people are impacted by the findings.

“世界上25%的人口生活在一个湖泊流域，这一趋势正在下降，这确实引起了我们的注意，”他继续说，这意味着大约20亿人受到了这一发现的影响。

Unlike rivers, which have tended to hog scientific attention, lakes aren't well monitored, despite their critical importance for water security, said Rajagopalan.

拉贾戈帕兰说，与河流不同，湖泊往往会引起科学界的注意，尽管它们对水安全至关重要，但它们并没有得到很好的监测。

But high profile environmental disasters in large water bodies like the Caspian Sea and the Aral Sea, signaled to researchers a wider crisis.

但在里海和咸海等大型水体中发生的引人注目的环境灾难，向研究人员发出了更广泛的危机信号。

To study the question systematically, the team, which included scientists from the United States, France, and Saudi Arabia, looked at Earth's biggest 1,972 lakes and reservoirs, using observations from satellites from 1992-2020.

为了系统地研究这个问题，由来自美国、法国和沙特阿拉伯的科学家组成的研究小组，利用1992年至2020年的卫星观测数据，研究了地球上最大的1972个湖泊和水库。

They focused on larger freshwater bodies because of the better accuracy of satellites at a larger scale, as well as their importance for humans and wildlife.

他们之所以把重点放在更大的淡水水体上，是因为卫星在更大范围内的精度更高，而且它们对人类和野生动物也很重要。

Their dataset merged images from Landsat, the longest-running Earth observation program, with water surface height acquired by satellite altimeters, to determine how lake volume varied over nearly 30 years.

他们的数据集将运行时间最长的地球观测项目Landsat的图像与卫星高度计获得的水面高度相结合，以确定近30年来湖泊体积的变化情况。

The results: 53 percent of lakes and reservoirs saw a decline in water storage, at a rate of approximately 22 gigatonnes a year.

结果是:53%的湖泊和水库的储水量以每年约220亿吨的速度下降。

Over the whole period studied, 603 cubic kilometers of water (145 cubic miles) was lost, 17 times the water in Lake Mead, the United States' largest reservoir.

统观整个研究期，消失了603立方千米的水(145立方英里)，是美国最大水库米德湖水量的17倍。