水旱轮作模式下作物配置和肥水优化对作物产量及土壤养分的影响

摘要

[Objective] The present paper mainly explored the crop output and soil nutrients by different crop allocation of the rotation and management measures in Southwest China,aiming to establish an efficient rotation mode and scientific fertilization method.[Method] Rotation mode with rice-beans and rice-garlic and management measures with CK,conventional treatment,optimized treatment,reducing irrigation / straw mulching were set up in 2013,and crop yield,output value,VCR and soil nutrient were determined.[Result] The crop yield,output value and VCR of the rotation crop were not affected by partially replacing chemical fertilizer with organic fertilizer,and the soil organic matter was increased by 6.85 ％ compared with conventional treatment.The alternation of water and drought rotation could significantly affect soil pH value,organic matter and available N,P and K.The content of soil organic matter,available nitrogen,available phosphorus and available potassium in the dry season were increased by 8.31 ％,44.55 ％,52.61％ and 22.73 ％,respectively.After 5 years of paddy rice-upland crop rotation,soil available nitrogen,available phosphorus and available potassium were increased by 21.25 ％,62.91％ and 88.04 ％ respectively.The economic benefits and soil nutrient content of rice-garlic rotation were higher than that of rice-broad bean,output value and VCR were increase by 56.70 ％,45.65 ％,soil organic matter,available nitrogen,available phosphorus and available potassium were increased by 2.93 ％,23.94 ％,30.09 ％ and 35.96 ％,respectively.In paddy rice-upland crop rotation system,soil productivity could be improved significantly by planting high value-added cash crop after rice.[Conclusion] The rice-garlic rotation could achieve high economic benefits and improve soil fertility,and the crop yield was not affected by reducing irrigation,partially replacing chemical fertilizer with organic fertilizer.%[目的]主要探索西南地区周年水旱轮作模式的高效作物配置,以及相应肥水应用措施对作物经济效益和土壤养分含量的影响,以期建立高效的水旱轮作模式和科学的施肥体系.[方法]试验通过设置水稻-蚕豆、水稻-大蒜2种轮作模式及CK、常规处理、优化处理、优化处理+秸秆覆盖4种管理措施,统计2015-2017年作物产量、产值、产投比,测定2013-2017年土壤养分含量,比较分析了轮作作物和施肥制度对作物经济效益和土壤养分的影响.[结果]相比于常规处理,在适当减少氮磷化肥施用量及灌水量的情况下增施有机肥,水旱轮作的作物产量、产值、产投比不受影响,增施有机肥有利于土壤有机质积累,提高土壤养分含量,土壤有机质可提高6.85％.水旱轮作交替可显著影响土壤pH、有机质及速效氮磷钾含量.旱季土壤有机质、速效氮、有效磷、速效钾含量相比水稻季分别增加8.31％、44.55％、52.61％和22.73％.经过5年水旱轮作后,土壤pH值下降.优化处理土壤有机质含量保持不变,施肥处理土壤速效氮、有效磷、速效钾含量分别增加了21.25％、62.91％和88.04％.稻后配置附加值较高的经济作物,能显著提高水旱轮作系统周年土地生产力.稻蒜轮作的经济效益和土壤养分含量均高于稻豆轮作,平均产值提高56.70％,产投比提高45.65％,土壤有机质、速效氮、有效磷、速效钾分别增加了2.93％、23.94％、30.09％和35.96％.[结论]在西南水旱轮作区,水稻-大蒜轮作可获得较高的经济效益,且在适当减少水分灌溉和化肥用量并适当增施有机肥的前提下,作物产量并未受影响,土壤保持较高生产力.