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珠峰變綠了,亞洲14億人或將面臨更高洪災風險
2020-01-11 17:22   来源:  www.rozanews.com   评论:0 点击:

珠峰變綠了,亞洲14億人或將面臨更高洪災風險这是科学家近日获得的惊人事实。借助美国宇航局陆地卫星(Land

这是科学家近日获得的惊人事实。借助美国宇航局陆地卫星(Landsat)在1993至2018年间拍摄的卫星图像,英国埃克塞特大学的研究人员对喜马拉雅地区的植被覆盖率进行了测量。结果发现,在海拔4150至6000米之间有植物覆盖的高山冰缘植物区面积有所增加,甚至达到同一高度永久冰川和雪面积的5至15倍。其中在海拔5000至5000米的地带植被增速最快。

This is a surprising fact that scientists have acquired recently. Researchers at the University of Exeter in England measured vegetation coverage in the Himalayas, with the help of satellite images taken by NASA's Landsat between 1993 and 2018. The results showed that the area of plant-covered alpine ice-rim plant areas between 4150 and 6000 meters above sea level had increased, even to 5 to 15 times the area of permanent glaciers and snow at the same height. Among them, vegetation growth in the 5000-5000-meter-high zone is the fastest.

高山冰缘植物区介于林木线和雪线之间。这个高度被认为接近植物能够生长的海拔极限。在这个高度上因为有季节性积雪,草和灌木等植被能够在冰雪覆盖下生长,被称为冰缘植物。

The high mountain ice margin plant area is between the forest line and the snow line. This height is thought to be close to the altitude limit at which plants can grow. At this height, because of the seasonal snow cover, vegetation such as grass and shrubs can grow under ice and snow, known as ice rim plants.

高山冰缘植物区面积增加对地区水循环的具体影响还未可知,但对广袤的兴都库什喜马拉雅地区(HinduKushHimalayanRegion)来说,却可能面临不断提高的洪灾风险。兴都库什喜马拉雅地区面积约为420万平方公里,素有“亚洲水塔”之称,雅鲁藏布江、恒河、印度河、湄公河、黄河、长江等亚洲最主要河流都发源于此,直接或间接依赖这些水源生存的人口超过14亿。

The specific impact of the increase in the area of the alpine ice-rim plant area on the regional water cycle is unknown, but for the vast Hindu Kush Himalayan Region, the risk of rising flooding is likely. The region covers an area of about 4.2 million square kilometers, known as the \"water tower of Asia,\" where the Yarlungzangbo, Ganges, Indus, Mekong, Yellow River and Yangtze River originate, with more than 1.4 billion people living directly or indirectly on these sources.

埃克塞特大学环境和可持续性研究所研究员安德森(KarenAnderson)表示,2000年至2016年间喜马拉雅山脉冰川融化的速度已经翻了一番,过去40年里有四分之一的冰层流失。研究指出,喜马拉雅地区的生态系统在气候引起的植被覆盖率变化面前已经不堪一击。

Karen Anderson, a researcher at the Institute for Environment and Sustainability at the University of Exeter, said the rate of melting glaciers in the Himalayas had doubled between 2000 and 2016, with a quarter of the ice losing in the past 40 years. The study points out that the Himalayan ecosystem is vulnerable to climate-induced changes in vegetation cover.

有关北极地区的相关研究发现,因为植被会吸收更多光线、提高土壤温度,植被覆盖率提高使得周边地区温度进一步提高。但安德森认为,喜马拉雅地区的状况可能会有所不同。例如在西藏进行的研究发现,通过植物叶子蒸发的水汽实际上能够带来冷却效应。

Studies on the arctic have found that because vegetation absorbs more light and raises soil temperature, increased vegetation coverage increases temperatures in the surrounding area. But Anderson believes conditions may be different in the Himalayas. Studies in Tibet, for example, have found that water vapor evaporated through plant leaves can actually have a cooling effect.

埃克塞特大学的研究称,虽然没有涉及冰缘植被扩散的原因,但研究结果与全球变暖导致的“极低温”(即温度低于植物能够生长的最低温度)区域面积缩小趋势存在一致性。

Although there are no reasons for the spread of ice-edge vegetation, the results are consistent with a shrinking trend in the area of \"extremely low temperatures \"(i.e., temperatures below the minimum that plants can grow) caused by global warming, according to the University of Exeter.

安德森指出,植被覆盖率变化起因有很多,尤其是在喜马拉雅地区这样广阔的,可能会是多个原因共同作用的结果,包括土地使用、气温、降水、二氧化碳排放等方面的变化,当然这之中也少不了全球气候变化的作用。

Anderson points out that there are many causes of change in vegetation cover, especially in the himalayas, which can be the result of a combination of factors, including changes in land use, temperature, precipitation, carbon dioxide emissions, and, of course, global climate change.


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