Lakes on Mongolian Plateau shrink significantly

Lakes on the Mongolian Plateau, composed mainly of Inner Mongolia in China and the Republic of Mongolia, have been experiencing remarkable shrinkage over the past three decades due to intensive human activities and climate changes, a study by Chinese researchers suggested Monday.

Lakes are widely distributed on the 2.75-million-sq-km Mongolian Plateau and are critical to sustain the 28 million people on the region, according to the study published in the U.S. journal Proceedings of the National Academy of Sciences.

In the study, researchers from Peking University and Chinese Academy of Sciences (CAS) established a database of lakes for the entire plateau using images of the U.S. Landsat satellites from the 1970s to 2000s, combined with ground-based censuses to explore the lake changes and the associated driving factors.

The researchers found the number of lakes has declined rapidly between the 1980s and 2010, with a greater decline in China's Inner Mongolia than in Mongolia.

"The plateau had a total of 785 lakes with a water surface area greater than 1 sq km in the late 1980s, including 427 lakes in Inner Mongolia and 358 lakes in Mongolia, but the number has decreased to 577 around 2010, with the disappearance of 145 lakes in Inner Mongolia and 63 lakes in Mongolia," lead author Jingyun Fang, professor of Peking University, told Xinhua.

"Accompanying the decrease in the number of lakes, a rapid shrinkage of lake surface area has also occurred, especially in Inner Mongolia: the total water surface area of the lakes decreased from 4,160 sq km in the late 1980s to 2,901 sq km around 2010," said Fang, also director of the Institute of Botany at the CAS.

Statistical analyses suggested that in Mongolia precipitation was the dominant driver for the lake changes, and that in Inner Mongolia coal mining was most important in its grassland area and irrigation was the leading factor in its cultivated area, Fang said.

He warned that the deterioration of lakes is expected to continue in the following decades unless the region has more rainfall as well as effective control measures over the increasing exploitation of underground mineral and groundwater resources.

"Although both governments (China and Mongolia) have made efforts to prevent ecological degradation, such as controlling grazing, returning farmland to grassland, and recharging some lakes through water diversion projects, more effective action is urgently required to save these valuable lakes," the researchers wrote in their paper.

"Without it, the lake-loss-induced damages to the natural systems, nomadic culture, and plateau civilization will be disastrous," they warned.

《Lakes on Mongolian Plateau shrink significantly》永久阅读地址: http://91kudian.com/yingyu/19778/