不同耕作措施对宁南地区土壤物理性质及作物产量的影响

Effects of Different Tillage Practices on Soil Physical Properties and Crop Yield in the Region of Southern Ningxia

【目的】针对宁夏南部旱地降水不足、耕层浅薄、作物产量低等问题,探讨不同耕作措施对宁南地区土壤物理性质及作物产量的影响,为合理改善旱地耕层土壤结构、选用适宜耕作措施和作物增产增效提供一定的理论支撑。【方法】以马铃薯和春小麦为供试作物,在宁南旱区开展2年(2019-2020年)大田试验,设置2种耕作方式(翻耕和深松)和4种耕作深度(20、30、40和50 cm),分别为传统翻耕深度20 cm、深翻耕30 cm、深松30 cm、深松40 cm、深松50 cm等5种不同耕作措施,以传统翻耕深度20 cm处理为对照,研究不同耕作方式结合深度措施对作物收获期土壤容重、生育期土壤紧实度与水分、生育期作物生物量、产量和水分利用效率的影响。【结果】深松50 cm处理能显著降低马铃薯季和春小麦季0—60 cm层土壤容重,平均分别较对照显著降低6.49%和6.94%。马铃薯季和春小麦季各处理生育期平均土壤紧实度均以深松50 cm处理最低,分别较对照显著降低19.32%和8.11%。深松50 cm处理对提高马铃薯和春小麦季作物各生育期0—100 cm层土壤蓄水量效果最佳,平均分别较对照显著提高13.58%和25.66%。在作物整个生育期,马铃薯季和春小麦季各生育期作物干物质累积量均以深松40 cm处理最高。马铃薯季和春小麦季不同耕作处理下作物产量、纯收益和水分利用效率均以深松40 cm处理最高,马铃薯季分别较对照显著增加15.20%、18.90%和9.10%,春小麦季分别显著增加59.24%、88.20%和28.98%。不同耕作方式结合深度对土壤蓄水量、作物生物量及产量均呈极显著影响,而土壤容重和紧实度受耕作方式影响显著。【结论】不同耕作方式结合深度措施可显著改善土壤耕层结构,提高作物生育期土壤蓄水量,进而实现马铃薯和春小麦季作物产量和水分利用效率的提高,其增产增收效果以深松40 cm处理较好,可在宁南地区马铃薯和春小麦高产高效栽培中进一步推广应用。

【Objective】In order to solve the problems of insufficient precipitation,shallow plough layer and low water use efficiency in the dry land of Southern Ningxia,we investigated the effects of different tillage practices on soil physical properties and crop yield in the region of southern Ningxia,and provided certain theory support for improving the topsoil structure reasonably in dryland,selecting the suitable tillage practice and increasing crop yield and benefit.【Method】using potato and spring wheat as test crops,two tillage methods and four tillage depths of conventional ploughing 20 cm(C20,as a control),deep ploughing 30 cm(C30),subsoiling 30 cm(S30),subsoiling 40 cm(S40)and subsoiling 50 cm(S50)were set in arid region of southern Ningxia between 2019 and 2020 for the two-year field experiment to study the effects of different tillage methods with depths on soil bulk density during the harvest period,soil compactness water storage,and crop biomass during the growth periods,,yield and water use efficiency.【Result】The average soil bulk density at 0-60 cm layer in potato season and spring wheat season under the S50 treatment was significantly decreased by 6.49%and 6.94%,compared with the control treatment.In the whole growth period,the average soil compactness with the S50 treatment in potato season and spring wheat season was the lowest,which was significantly increased by 19.32%and 8.11%,respectively,compared with the control treatment.The improvement in the soil water storage with the S50 treatment during the whole growth period in potato season and spring wheat season was the best,which was significantly increased by 13.58%and 25.66%,respectively,compared with the control treatment.The S40 treatment had the highest dry matter accumulation in potato season and spring wheat season.Crop yield,net income and water use efficiency were the highest under the S40 treatment in potato season and spring wheat season,which were significantly increased by 15.20%,18.90%and 9.10%in potato season,and increased by 59.24%,88.20%and 28.98%in spring wheat season,when compared with the control treatment.The tillage methods with depths had extremely significant effects on soil water storage,crop biomass and yield,while soil density and compactness were extremely affected by tillage methods.【Conclusion】The tillage method combined with depth could significantly improve the topsoil structure,and increase soil water storage during the crop growing period,thereby promoting the increase of crop yield and water use efficiency.The subsoiling 40 cm treatment had the best effect of crop yield and income increasing in potato and spring wheat season,and it could be further promoted and applied in the cultivation of potato and spring wheat for high yield and efficiency in the region of southern Ningxia.