不同间作模式对山苍子光合特性及其栽培土壤水分和养分的影响

Effects of different intercropping patterns on Litsea cubeba photosynthetic characteristics and soil moisture and nutrients

【目的】研究不同间作模式对山苍子光合特性及其栽培土壤水分和养分的影响情况,为筛选出较好的山苍子间作模式提供理论依据和生产指导。【方法】以同一家系的6年生山苍子植株为试验材料,采用顺序排列试验设计方法,共设计6个间作处理,分别为清耕、山苍子间作白车轴草、山苍子间作红车轴草、山苍子间作高羊茅、山苍子间作百日草、山苍子间作万寿菊,并对不同间作模式下山苍子的光合参数、栽培土壤中水分和养分含量进行测定分析。【结果】间作高羊茅和间作百日草均能缓解山苍子的“午休”现象,均能促进山苍子的生长发育,这两种间作处理的山苍子其净光合速率日均值分别为5.18与4.89μmol∙m^(-2)∙s^(-1);间作白车轴草和间作高羊茅的山苍子其气孔限制值均在16:00时达到了最高值,分别为64%与77%,且其叶片的平均光能利用率分别达到0.57%与0.61%;间作万寿菊和间作高羊茅均能较为显著地提高山苍子叶片的水分利用效率及其栽培土壤的水分含量,其水分利用效率平均值较清耕处理山苍子的平均值分别高出26%与32%,因其用于光合作用的有效水分较多,故其抗旱能力均强于其他处理的;间作万寿菊的山苍子其栽培土壤的水分含量最高,且与清耕处理的相比,其水分含量高出16.15%;间作万寿菊和间作高羊茅均可有效增强山苍子适应强光的能力而降低叶温。间作百日草、间作万寿菊和间作高羊茅均可显著地提高其栽培土壤中的全氮含量,间作白车轴草的土壤全钾和速效磷含量均高于清耕处理的,间作红车轴草可以显著地提高其栽培土壤中有机质和铵态氮的含量,间作红车轴草和间作高羊毛均可有效提高其栽培土壤中速效磷与速效钾的含量。【结论】间作红车轴草和间作高羊茅均可有效增强山苍子适应强光环境的能力,均有利于山苍子营养物质的积累,促进山苍子的生长发育,提高其经济效益;间作高羊茅和间作万寿菊均能增强山苍子的抗旱能力;间作万寿菊、间作百日草、间作高羊茅和间作红车轴草均可较为显著地提高山苍子栽培土壤的养分含量。

【Objective】The aim was to study the effects of different intercropping patterns on Litsea cubeba photosynthetic characteristics,soil moisture and nutrients so as to provide theoretical basis and production guidance for screening better intercropping patterns of L.cubeba.【Method】The L.cubeba seedlings of the same family was used as the experimental material,and six treatments were designed by the sequential design method,which were clear tillage,L.cubeba intercropping with Trifolium repens L.,L.cubeba intercropping with Trifolium pratense L.,L.cubeba intercropping with Festuca arundinacea,L.cubeba intercropping with Zinnia elegans,and L.cubeba intercropping with Tagetes erecta L..The photosynthetic indexes,soil moisture and nutrient contents of L.cubeba under different intercropping modes were measured and analyzed.【Result】Under different intercropping patterns,intercropping F.arundinacea and Z.elegans could alleviate the“noon break”phenomenon of L.cubeba,which was conducive to promoting the growth and development of L.cubeba and improving the benefits.The daily average changes of net photosynthetic rate of L.cubeba were 5.18 and 4.89μmol∙m^(-2)∙s^(-1) respectively.The stomatal limitation of L.cubeba intercropped with T.repens L.and F.arundinacea reached the highest values of 64%and 77%at 16:00,respectively;the average light energy utilization rate of L.cubeba leaves reached 0.57%and 0.61%.Intercropping T.erecta L.and F.arundinacea significantly improved water use efficiency of L.cubeba leaves and soil water,and its average water use efficiency was 26%and 32%higher than that of clear tillage L.cubeba,respectively.Its available water for photosynthesis was more,and its drought resistance was stronger than other treatments.The soil water content of L.cubeba intercropped with T.erecta L.is the highest,which is 16.15%higher than that of clear tillage.Combined with its photosynthetic parameters,intercropping T.erecta L.and F.arundinacea effectively improved L.cubeba ability to adapt to strong light and reduced leaf temperature.Intercropping Z.elegans,T.erecta L.and F.arundinacea significantly increased soil total nitrogen;intercropping T.repens L.significantly increased soil total potassium and available phosphorus content,while intercropping T.pratense L.significantly increased soil organic matter and ammonium nitrogen content;intercropping T.pratense L.and F.arundinacea effectively increased soil available phosphorus and available potassium content.【Conclusion】Intercropping T.pratense and F.arundinacea can effectively promote L.cubeba adaptation to strong light environment,and is beneficial to L.cubeba nutrient accumulation,growth and development,and increase its benefit.Intercropping F.arundinacea and T.erecta L.can improve the drought resistance of L.cubeba.Intercropping T.erecta L.,Zinnia elegans,F.arundinacea and T.pratense L.pratense significantly improved the soil nutrient content of L.cubeba.