甘肃特大沙尘暴的危害与对策

Damages and Countermeasures of Catastrophic Sandstorm Occurred in Gansu Province

甘肃河西走廊于1993年5月5日14—20时发生特大沙尘暴。黑霾一般高度为300—400米,最高700米;锋面前移速度平均为50—60公里/小时,最大76公里/小时;瞬时风速在20米/秒以上,最大达34米/秒;能见度为0—100米。这次沙尘暴给灾区工农业生产和人民群众的生命财产造成巨大损失。直接经济损失达2.36亿元。根据典型地区调查分析,灾情多发生在防护林不够完整的老绿洲和新垦灌区。为此,建议应进一步完善由沙生植被,大型阻沙林带和护田林网组成的绿洲防护体系,加速新垦区林网化建设。封育现有天然沙生植被。新垦荒地多种具有覆盖作物性质的小麦,不种或少种瓜类,棉花,甜菜等不耐风蚀沙割的双子叶作物。

A Catastrophic sandstorm occurred at 14 : 00—20 : 00 on May 5,1993. The height of dust cloud ranged between 300—400m,with a maximum height reaching 700m. The maximum velocity of the sandstorm was 76km/hr,instantaneous wind speed 20m/s or more,maximum wind speed 34m/s. This sandstorm caused great damages to industrial and agricultural production, the direct economic loss amounted to 236 million yuan. According to survey and analytical data in typical regions, hazards are mainly occurred in the old oases and newly—opened irrigation regions, where there is no perfect shelterbelt. The main countermeasures to control sandstorm include establishment of psammophile vegetation,large—scale sandbreak forest and farmland shelterbelt as well as protection of existing vegetation.