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我区推广桤木带叶上山栽植,于1974年秋季在点上试验成功,后经多点试验,逐步扩大推广面积,取得成效,现将调查情况报告于后.一.地理位置和自然环境本区位于四川盆地西北边缘,地貌以中低丘陵为主,海拔430—680m.雨热同季,四季分明.年平均气温16.3℃,无霜期272天;年平均降水量963mm,多集中在6—9月,占全年降水量的75.5%,冬干春旱严重,全年平均日照数1298小时,日照率为29%.全区林业用地39万多亩,紫色土类占64.4%,黄泥土类占35.6%,pH值多在5—8之间,一般山坡土层厚度在40—60cm.
My area promotion alder with leaves up the mountain planted in the fall of 1974, the successful test at the point, after more tests, and gradually expand the promotion of the area and achieved results, the investigation is now reported in the following: 1. Geographical location and the natural environment of this The area is located in the northwestern edge of the Sichuan Basin, the main landform is low and medium hills, elevation 430-680m. Rain and heat in the same season, four seasons. The annual average temperature of 16.3 ℃, frost-free period of 272 days; annual average precipitation of 963mm, more concentrated in 6-9 Month, accounting for 75.5% of the annual precipitation, winter dry spring drought, the annual average number of 1298 hours of sunshine, the sunshine rate of 29% .Area of 390000 mu of forestry land, purple soil accounted for 64.4%, yellow soil class Accounting for 35.6%, pH value between 5-8, the general slope soil thickness of 40-60cm.