修枝对复合农林系统内小气候及作物生长的影响

对复合农林系统内的杨树进行4种不同强度的修枝处理，分别为修掉树冠高度的1/6、2/6、3/6、4/6，以CK(不修枝)为对照，对复合农林系统内的小气候和林下作物生长情况进行了研究。结果表明:修枝能有效增加林下光合有效辐射39.7%～98.9%，随之引起其他气候因子变动，包括增高林下气温及叶温、降低空气相对湿度并减少浅层土壤的含水量。修枝强度越大，这种增温和减湿的作用越明显。就林下玉米生长情况而言，修枝能有效增加玉米的净光合速率和蒸腾速率，并显著促进玉米植株增高、增粗、增重，且越到后期修枝对玉米生长的促进作用越明显。修枝能有效增加林下玉米产量，并主要通过增加玉米穗数增产。说明修枝在保证林冠功能的前提下，作为复合农林系统优化措施是可行的。 

Effects of different pruning intensity on microclimate,growth and yield of crops in agroforestry systems

In order to demonstrate the feasibility of pruning as an optimization measure for agroforestry system,four different pruning intensity treatments,comprising P1(1/6 height of crown cut down),P2(2/6 height of crown cut down),P3(3/6 height of crown cut down)and P4(4/6 height of crown cut down)in contrast to no pruning(CK),were applied to the poplar trees in an agroforestry system.The authors found that pruning can increase photosynthetically active radiation by 39.7%-98.9%,following this,air temperature in the...