一、河西地区营林的必要性、可能性甘肃河西地区是著名的古绿州,是西北的商品粮基地。境内地域辽阔,总面积27.92万平方公里,占全省61.54％。属荒漠气候,走廊区干燥度4—27之间,由东南往西北递增。本区沙漠戈壁广阔,共17814万亩,占总面积的43.63％,其中沙漠4382万亩,戈壁13432万亩,有丰富的沙物质基础。再加,本区受蒙古高压控制,是我国著名的大风口与过风道,年平均风速2—3米/秒,全区八级以上大风日数25—70天,全年风沙日数34—145天,风力强劲,具备形成风沙流危害绿州的强大动力因素。丰富的沙物质与强大的动力因素相结合,使 First, the necessity and possibility of silviculture in Hexi area Hexi area of ​​Gansu is a famous ancient green state and is the commodity grain base in northwest China. The territory of vast territory, with a total area of ​​279,200 square kilometers, accounting for 61.54% of the province. Is a desert climate, corridor area between 4-27 dryness, increasing from southeast to northwest. The vast desert Gobi in this area, a total of 178.14 million mu, accounting for 43.63% of the total area, of which 4382 mu of desert, Gobi 13432 mu, rich in sand material basis. In addition, this area is controlled by the high voltage in Mongolia. It is a famous outlet and air duct in China. The annual average wind speed is 2-3m / s. The typhoon days of Grade B and above in the region are 25-70 days. The annual number of sandstorms is 34-145 Days, strong winds, with the formation of wind and sand flow hazards of Green State powerful driving force. Rich sand material combined with powerful dynamic factors