切根贴膜对豫东平原农田防护林白花泡桐光合能力的影响  

Effects of root excision mulched with film on photosynthesis of Paulownia fortunei in farmland shelterbelts in eastern Henan Plain

作　　者：陈本学 李雁冰[1,2] 张慧斌 王娅婷[1,2] 李文博 CHEN Benxue;LI Yanbing;ZHANG Huibin;WANG Yating;LI Wenbo(Zhoukou Normal University,Zhoukou 466001,Henan,China;Zhoukou Garden Landscape Engineering Technology Research Center,Zhoukou 466001,Henan,China)

机构地区：[1]周口师范学院,河南周口466001 [2]周口市园林景观工程技术研究中心,河南周口466001

出　　处：《生态学杂志》2024年第4期1008-1016,共9页Chinese Journal of Ecology

基　　金：河南省科技攻关项目(212102110016);周口师范学院科研启动经费研究项目(ZKUNC2020032)资助。

摘　　要：农田防护林是豫东平原“中原粮仓”的重要生态屏障;切根贴膜在高效缓解林带胁地效应的同时,亦对其自身成长过程产生显著影响。本研究以豫东平原农田防护林白花泡桐(Paulownia fortunei)为对象,探究不同距离(1、2和3 m)切根贴膜处理对泡桐林带叶片光合特性的影响,试图从光合生理角度揭示泡桐防护林切根贴膜的生长效应与内在机制。结果表明:(1)切根贴膜处理显著降低叶片净光合速率(P_(n)),近距离(1 m)处理降低作用最明显,其通过造成P_(n)和蒸腾速率(T_(r))显著下降,实现对叶片光合能力的负向效应;(2)远距离(3 m)主要造成P_(n)显著下降,对T_(r)影响不大,造成叶片瞬时水分利用效率(iWUE)显著降低,不利于植物生长;(3)随机森林分析进一步发现,叶片P_(n)和iWUE是响应不同距离的切根贴膜处理的主要指标。综合比较,距树干2 m处切根贴膜白花泡桐叶片光合能力最强,叶片iWUE最好。Farmland shelterbelt is an important ecological barrier of“the Granary of Central Plains”in the eastern Henan Plain.Root cutting and film mulching can effectively alleviate the negative effects of shelterbelt on cropland,with impacts on tree growth.Taking Paulownia fortunei in farmland shelterbelts in the eastern Henan Plain as the research object,we explored the effects of different distances(1,2 and 3 m)of root cutting and film mulching on photosynthetic characteristics of P.fortunei,to reveal the growth effect and internal mechanism of P.fortunei after root cutting and film mulching from the perspective of photosynthetic physiology.The results showed that:(1)Root cutting and film mulching significantly reduced net photosynthetic rate(P_(n)),and the effect of the short distance(1 m)treatment was the most obvious,which had a negative effect on the photosynthetic capacity by significantly decreasing P_(n) and transpiration rate(T_(r));(2)Long distance(3 m)treatment mainly caused a significant decrease in P_(n),but had little effect on T_(r),resulting in a significant decrease in instantaneous water use efficiency(iWUE),which was not conducive to plant growth;(3)Results of random forest analysis showed that leaf P_(n) and iWUE were the main indices responding to different distances of root cutting and film treatment.Comprehensive comparison showed that root cutting and film mulching 2 m away from the trunk of P.fortunei had strongest photosynthetic capacity and highest iWUE.

关 键 词：农田防护林 断根 泡桐 光合特性 随机森林 

分 类 号：S792.43[农业科学—林木遗传育种]