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一、榆林自然地理概况榆林地处毛乌素沙漠边缘,是黄土高原与沙漠接襄地带。北部属典型的新月型,沙丘链,海拔1070 -1080米,沙丘高度一般3-7米,经过人工治沙造林,现属于半固定沙地。气候属温带干旱、半干旱大陆季风气候。年平均气温7.9-11.3℃;降水量 414.4mm左右;日照时数为2593.5-2914.2h;蒸发量在1152.2-1289.7mm之间;≥10℃以上积温 3397℃。无霜期134-169天;干燥度1.5-1.6;空气
First, the natural geography of Yulin Yulin is located in the margins of the Maowusu desert, the Loess Plateau and desert Xiangxiang area. The north is a typical crescent-shaped, dune chain, 1070 -1080 meters above sea level, sand dunes generally 3-7 meters in height, after artificial desertification afforestation, now belonging to the semi-fixed sand. Climate is a temperate arid, semi-arid continental monsoon climate. The average annual temperature of 7.9-11.3 ℃; precipitation 414.4mm or so; sunshine hours for the 2593.5-2914.2h; evaporation in the 1152.2-1289.7mm; ≥ 10 ℃ above the temperature 3397 ℃. Frost-free period 134-169 days; Dryness 1.5-1.6; Air