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水磨河林场,位于神木县城北15华里毛乌素沙漠南缘的长城沿线上,施业面积15万亩。立地条件复杂,施业区多为起伏连绵的新月型、长条型、椭圆型等不同形状的沙丘。迎风坡面向西北,部分地段受小气候的影响,呈现形似锅底式的沙窝。丘高一般为10～20米,最高达25米以上。迎风坡8～12度,背风坡25～32度。地势较低的近滩地区,沙丘较低。沙丘自西北向东南移动,每年前进1.5～4米左右。在不同小气候条件下,其方向、高低、移速亦有差异。因沙丘分布及位置不同,沙地的机械组成也有差别。一般迎风坡沙粒较大,以中沙(直径0.5毫米～0.8毫米)、细沙(0.25～0.4毫米)占主要成份,有时含有粗沙(0.9～
Shuimo River Forest Farm, located in the northern margin of the Muwu desert in the north of Shenmu County, 15 kilometers along the Great Wall, Shi industry area of 15 mu. Site conditions are complex, mostly in the construction area of rolling crescent-shaped, elongated, oval and other shapes of sand dunes. Windward slope facing the northwest, part of the affected by the microclimate, showing the shape of the bottom of the sand pot. Qiu high is generally 10 to 20 meters, up to 25 meters or more. Windward slope 8 ~ 12 degrees, leeward 25 ~ 32 degrees. Near the beach area on the lower ground, dunes are low. Dunes move from northwest to southeast, progressing 1.5 to 4 meters annually. In different microclimate conditions, the direction, height, speed also vary. Due to the distribution and location of sand dunes, the mechanical composition of sand is also different. The general windward slope grit larger, with sand (diameter 0.5 mm ~ 0.8 mm), fine sand (0.25 ~ 0.4 mm), the main ingredient, sometimes containing coarse sand (0.9 ~