杨粮间作系统林木遮荫面积和株行距研究  

The study on tree shading area and spacing under poplar-crop intercropping system

作　　者：袁玉欣[1] 王金凤 闫同惠 王颖[1] 李保会[1] 

机构地区：[1]河北农业大学林学院,河北保定071000 [2]河北省林业学校,河北石家庄050000 [3]河北省藁城市林业局,河北藁城052100

出　　处：《河北农业大学学报》2002年第2期32-37,共6页Journal of Hebei Agricultural University

基　　金：河北省自然基金资助项目 (3 93 0 3 3 ) ;河北省林业厅重点资助项目 (95 1610 2 );河北省世界银行贷款国家造林资助项目

摘　　要：报道了对华北平原农区杨粮间作复合生态系统林木理论遮荫面积和株行距的研究结果 ,给出了计算林木行内郁闭前后平均单株遮荫面积的方程 ;为保证南北行向的林木行内和行间均不造成重复遮荫 ,推导出了计算公式。在华北地区应用时 ,最小株距的计算可以采用 0 5× (冠幅 +冠长 ) ,最小行距可以采用2 9倍冠长 ;同时 ,要保证间作系统的长期性和稳定性 ,注意对杨树的修枝 ,并且当杨树成林时 ,5m× 2The study on the theoretic tree shading area and spacing (including spacing within row and spacing between rows) was reported under poplar crop intercropping system in North China farm plain The average per tree shading area equations were respectively offered before and after the crown closed within row, and the poplar spacing equations that is to calculate the distance of no repeat shading on crop both within row and between rows were also inferred when it is in the N S direction They are shown as below: spacing within row L=l ctg h + d /2 ( 1 :crown length, h :the sun height angle, d :crown diameter) spacing betwwen rows L=(l ctg h + d /2)sin A ( A :the sun position angle).In order to avoid tree repeat shading in row and between rows, the smallest spacing in row appies about 0 5 times of the sum of tree crown diameter and the length as well as the smallest spacing between rows adoptes 2 9 times of tree crown length when they were used in North China farm plain The shaft cleaning on poplar was a powerful way to maintain intercropping system stability and sustainability through calculating to the no repeat shading spacing of the real stands The spacing of 5 m×25 m is proposed when poplar in the mature stage

关 键 词：杨粮间作系统 林木遮荫面积 株行距 混农林业系统 

分 类 号：S718.52[农业科学—林学] S181