减量施氮对甘蔗//大豆间作系统产量稳定性的影响  

Effect of Nitrogen Reduction on Yield Stability of Sugarcane-Soybean Intercropping System

作　　者：许霞 苟永刚 罗莎莎 王宇姝 余玲玲 王建武 XU Xia;GOU Yonggang;LUO Shasha;WANG Yushu;YU Lingling;WANG Jianwu(Key Laboratory of Tropical Agro-Environment,Ministry of Agriculture and Rural Affairs,Guangzhou,Guangdong 510642,China;Guangdong Provincial Key Laboratory of Eco-Circular Agriculture,Guangzhou,Guangdong 510642,China;College of Natural Resources and Environment,South China Agricultural University,Guangzhou,Guangdong 510642,China)

机构地区：[1]农业农村部华南热带农业环境重点实验室,广东广州510642 [2]广东省生态循环农业重点实验室,广东广州510642 [3]华南农业大学资源环境学院,广东广州510642

出　　处：《热带作物学报》2020年第7期1354-1365,共12页Chinese Journal of Tropical Crops

基　　金：国家自然科学基金项目(No.31600348)。

摘　　要：在广州华南农业大学试验中心,通过10 a(2009—2018年)的田间定位试验,对比研究了2种施氮水平[减量施氮300 kg/hm^2(N1)、常规施氮525 kg/hm^2(N2)]和4种种植模式[甘蔗单作(MS)、甘蔗//大豆1∶1间作(SB1)、甘蔗//大豆1∶2间作(SB2)、大豆单作(MB)]的甘蔗、大豆和系统总产量的动态变化,以及对甘蔗品质和土壤肥力的影响,采用Wi2(Wricke’s ecovalence)、变异系数(CV)和可持续指数(SYI)评价了产量的时间稳定性,旨在为华南蔗区农业绿色发展的可持续生产模式提供理论依据。结果表明:(1)各处理的甘蔗、大豆以及系统总产量呈现明显的年际变化。年份和种植模式对甘蔗和大豆产量有极显著影响,系统总产量受种植年份的极显著影响。施氮量对甘蔗、大豆和系统总产量均无显著影响。(2)不同间作模式的土地当量比(LER)均大于1,间作稳定且显著地提高了土地利用率。(3)不同处理甘蔗产量的Wi2和CV差异不显著,减量施氮单作甘蔗的SYI值显著高于常规施氮,表明减量施氮单作甘蔗的产量稳定性显著高于常规施氮处理。单作大豆产量的Wi2显著高于间作,说明单作大豆产量稳定性显著低于间作。不同处理的系统总产量Wi2值差异不显著,说明甘蔗//大豆间作和施氮量不影响系统总产量的稳定性。(4)种植年限的增加对甘蔗蔗糖分和纤维分、蔗汁糖锤度、蔗汁旋光度和蔗糖分无显著影响,同一年份不同种植模式和施氮量处理的甘蔗品质差异不显著。(5)与2010年相比,2018年底,除大豆单作模式外,其他处理的土壤pH、有机质、全氮含量显著下降,但所有处理的土壤全磷、有效磷和速效钾没有显著差异。甘蔗连作和连续施用化肥,导致土壤有机质逐步下降、pH降低。减量施氮甘蔗//大豆间作模式能够保持系统生产力和地力的稳定性,但需施用有机肥和推广蔗叶还田技术来培肥蔗田地力。Sugarcane is an important economic crop in South China.The yield and quality are declined because of the long-term practice of monoculture agriculture and high chemical nitrogen application.Intercropping system is a sustainable and stable agricultural practice that enables the effective utilization of water,nutrient and light.In the paper,a field experiment was conducted at Experimental Center of South China Agriculture University(23°08′N,113°15′E)for 10 years(from 2009 to 2018)to investigate the dynamic changes of sugarcane-soybean and system yields under two nitrogen levels[reduced rate 300 kg/hm^2(N1)and conventional rate 525 kg/hm^2(N2)]and four cropping patterns[sugarcane monocropping(MS),soybean monocropping(MB),sugarcane-soybean(1∶1)intercropping(SB1),and sugar cane-soybean(1∶2)intercropping(SB2)].The study analyzed the dynamic change of land equivalent ratio and evaluated the stability of system yield by Wi2(Wricke’s ecovalence),CV(coefficient of variation)and SYI(sustainability index),aiming to explore the effects of reduced nitrogen application on the time stability of sugarcane-soybean intercropping system in Guangdong,China.The yield of sugarcane,soybean and the total system under different treatment showed obvious annual dynamic changes and was significantly affected by different years and planting patterns.Nitrogen application level did not affect the yield of sugarcane,soybean and the system yield significantly.The land equivalent ratio(LER)of all intercropping systems was greater than 1(between 1.09 and 1.97)for 10 years,and the SB2-N1 optimally improved the land utilization rate among all treatments.There was no significant difference in Wi2and CV for sugarcane yield,but the SYI of MS-N1 was significantly higher than that of MS-N2.Meanwhile,the Wi2 value of monocropping soybean was significantly higher than that of intercropping pattern,and the yield stability of monocropping soybean was lower than that of intercropping soybean.And the stability of soybean yield under reduced nitrogen

关 键 词：甘蔗//大豆间作 减量施氮 产量稳定性 甘蔗品质 土壤肥力 

分 类 号：S344.2[农业科学—作物栽培与耕作技术] S147[农业科学—农艺学]