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为了掌握农桐间作在我县农业防护效益的科学数据,我们对大墙周公社五道口农桐间作地,1975年以来的粮食产量进行了调查,并于1980年6月对农桐间作地小麦产量和桐木蓄积量及其经济价值进行了调查分析。一、调查地概况与方法:调查间作面积40亩(129×207),树龄为13年生,株距5米,行距17米,每亩平均7.8株,郁闭度0.51,林冠透光度0.28,平均树高10.17米,平均枝下高4.6米,平均胸径
In order to grasp the scientific data of the agricultural protection effectiveness of Agropyron chinense in our county, we conducted a survey on the grain yield of Agropyron nilotatus Wudaokou since 1975, and conducted a survey on the wheat yield And Paulownia volume and its economic value were investigated and analyzed. I. Survey Survey Methods and Methods: The survey covers an area of 40 mu (129 × 207) with an age of 13 years. The plant spacing is 5 meters and the spacing is 17 meters. The average per acre area is 7.8, the canopy density is 0.51 and the canopy transmissivity is 0.28. The mean Tree height 10.17 meters, the average branch height of 4.6 meters, the average diameter at breast height