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榆林南部丘陵沟壑区，选择有代表性的米脂县高家沟、远志山村，建立树木（果树）引种观察园。８０年代初引进树种３４科６７属１１４种２７８个品种，经过１４年的自然选择，选出适宜本区生长经济效益较好的１６科３２属４７种１０６个品种。１９８７～１９９３年树木园土不下山，水不出沟，减沙１０４８７４ｔ／（ｋｍ￣２·ａ）。油松、刺槐、桃树等林地比农地土壤０～１０ｃｍ含水量增加６．８％～５９．２％，１１ｃｍ以下则有减少趋势。杏树、胡颓子、柠条等地比农地０～１０ｃｍ土壤含水量减少１６．４％～３３．８％。苹果的经济效益最高，１９９３～１９９４年远志山果园每ｈｍ￣２产值１４５７９元，比种马铃薯增加３．８６倍。
Yulin southern hilly and gully areas, choose a representative of the Mi Jiaxian Gaojiagou, Yuanzhi Village, the establishment of trees (fruit trees) Introduction Observation Garden. In the early 1980s, 34 species, 67 genera, 114 species and 278 species of 34 species were introduced. After 14 years of natural selection, 16 species, 32 genera, and 47 species and 106 species with good economic benefits were selected. From 1987 to 1993, the arboretum soil did not go downhill and the water did not go out of the trench, reducing 104874 t / (km ~ 2 · a) of sand. Pinus tabulaeformis, Robinia pseudoacacia, peach trees and other woodlands than the soil 0 ~ 10cm water content increased 6.8% ~ 59.2%, 11cm below the trend there is a decrease. Apricot, Elaeagnus, Caragana and other places than farmland 0 ~ 10cm soil moisture decreased by 16.4% to 33.8%. The highest economic benefits of apple, 1993 ~ 1994 Yuanzhi orchard hm ~ 2 output value 14,579 yuan per hm2, 3.86 times more than the kinds of potato.