陕北榆林、靖邊間的風沙問題,早已引人注意。流沙南侵的爲害性相當大:榆林城址原來靠近長城,歷史上曾經三次南遷,有“榆城三讓”的俗語。榆林城西15公里的保寧堡,70年前還是一個相當熱鬧的集鎮,因風沙侵襲,現在變得很冷落了。榆林城東20公里的長樂堡,在七、八年內,城內被沙埋去面積達2/3,西門的沙丘,高出城牆約3公尺餘。榆溪、無定兩河匯口的魚河堡,公元1852年(清咸豐二年)西門城牆因戰爭被毀,流沙由城的缺口侵襲,在最近100年間, The wind and sand problems between Yulin and Jingbian in northern Shaanxi have long drawn attention. The infiltration of infiltration of sand is quite damaging: Yulin City, the original site near the Great Wall, the history of the South moved to the south three times, “Yucheng three to” the saying goes. Baoning Fort 15 km west of Yulin, 70 years ago, or a very lively market town, because of sandstorms hit, and now it has become very cold. Changle Fort 20 kilometers east of Yulin City, in seven or eight years, the city was buried sand to an area of ​​2/3, Simon dunes, about 3 meters above the city wall. Yuxi, Wudinghe two rivers converge fish River Fort, AD 1852 (Qing Xianfeng two years) Simon Wall was destroyed due to the war, quicksand hit by the city’s gap in the last 100 years,