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石原大队位于陕县黄土丘陵区的张村原上。海拔700——800米,年降水量550毫米,多集中在夏秋两季,冬春干旱,大风较多,主风方向偏西。过去缺少森林复盖,水土流失严重,各种自然灾害不断发生,农业产量很低,粮食亩产200斤左右,棉花亩产20余斤,是一个缺粮缺(牛欠)的困难队。一九六七年,在大搞农田基本建设,土、水,林综合治理的群众运动中,建造了石原农田防护林网。根据因害设防的原则,主林带南北方向设置,带距200——250米,付林带东西方向设置,带距300——500米。林带与道路、水洰相结合,路洰侧各植树1——2行,株距2米。树种大部分为大官杨,有少量的泡桐。共营造4900余亩,构成了窄带式小网格防护林系统。目前林木生长良好,大官杨平均高16米,胸径24厘米;泡桐平均高10米,胸径30厘米。从一九七○年开始,林带发挥了愈来愈
Ishihara Brigade is located in the loess hilly Xian Zhangcun original. 700 - 800 meters above sea level, the annual rainfall of 550 mm, mostly concentrated in summer and autumn, winter and spring drought, more winds, the main wind direction west. In the past, there was a lack of forest cover, serious water and soil erosion, continuous occurrence of various natural disasters, low agricultural output, about 200 kg of grain per mu, and over 20 kg of cotton per mu. This is a difficult team lacking in food (cattle owed). In 1967, Ishida’s farmland shelterbelts were built during the mass movement that vigorously promoted farmland infrastructures, integrated management of soil, water and forests. According to the principles of fortification and fortification, the main forest with a north-south setting, with a distance of 200-250 meters, to pay the belt set east-west direction, with a distance of 300 - 500 meters. Forest belt and road, water 洰 combination, the road side of the tree planting 1-2 lines, spacing 2 meters. Most of the trees are big, with a small amount of paulownia. A total of more than 4,900 acres to create a narrow-band small grid shelter forest system. At present, trees grow well, the average high official Yang 16 meters high, diameter 24 cm; paulownia average 10 meters high, diameter 30 cm. Since 1970, the belt has been playing more and more