摘要：

保护性耕作与有机肥施用是黄土高原旱作农业区缓解生态脆弱问题的有效解决手段之一,合理的耕作与施肥措施对山西中部旱区实现麦玉一年两熟具有重要意义。以黄土高原旱作农田为研究对象,采用裂区试验设计,主区为3种耕作方式(深翻(DT)、深松(SS)、免耕(NT)),副区为4种施肥水平(不施肥对照(CK)、全量化肥(CF)、50%化肥+50%有机肥(OF)、全量有机肥(OM)),探究不同耕作与施肥方式下土壤容重、速效养分及麦玉周年产量的变化特征。结果表明,有机肥施用后SS、NT处理0~20 cm土壤容重较DT处理有所下降,其中小麦季SS+OF处理下耕层土壤容重为1.13 g/cm³,显著低于DT+OF处理。整个周年复种连作体系中,以NT+OM处理土壤质量含水量最高,较其他施肥处理平均升高7.88百分点;SS+OM处理下土壤的三相比更为理想,三相比偏离值偏低。3种耕作方式下,碱解氮与有效磷含量大小总体呈现OM>OF>CF>CK的趋势,速效钾含量与施肥方式存在极显著关系,其中CF处理下含量最高;玉米季增施有机肥较单施化肥显著提高了糯玉米鲜穗产量,但有机肥施用比例间的差异并不显著,SS+OM处理下麦玉周年产量最高,达19 145 kg/hm²。综上,该试验条件下,SS、NT耕作方式与有机肥施用结合可明显改善土壤的物理性状,碱解氮与有效磷含量也有一定程度的提升,其中,SS+OM处理更有利于黄土高原地区麦玉周年复种连作田产量的提升。

关键词: 麦玉周年产量, 耕作措施, 施肥方式, 土壤容重, 土壤三相比, 速效养分

Abstract:

Conservation tillage and organic fertilizer application are one of the effective solutions to alleviate ecological vulnerability in dry farming areas of the Loess Plateau.Reasonable tillage and fertilization measures are of great significance for the realization of two crops a year in the arid area of central Shanxi.The dry farmland in the Loess Plateau was taken as the research object,and the split-plot experimental design was adopted,the main area was three tillage methods (deep tillage (DT),deep loosening (SS),no tillage (NT)),and the sub-area was four fertilization levels (No fertilizer control (CK),full chemical fertilizer (CF),50% chemical fertilizer+50% organic fertilizer (OF),full organic fertilizer (OM)).The changes of soil bulk density,available nutrients and annual yield of wheat and maize under different tillage and fertilization methods were explored.The results showed that in 0-20 cm the soil bulk density of SS and NT treatments were lower than that of DT treatment after organic fertilizer application.The soil bulk density of SS+OF treatment was 1.13 g/cm³,which was significantly lower than that of DT+OF treatment in wheat season.In the whole annual rotation system,the soil mass water content of NT+OM treatment was the highest,which was 7.88 percent point higher than that of other fertilization treatments,and the three-phase ratio of soil under SS+OM treatment was more ideal,and the deviation value of three phase was low.Under the three tillage methods,the content of available nitrogen and available phosphorus generally showed the trend of OM>OF>CF>CK,and the content of available potassium was significantly related to the fertilization method,which was the highest under the CF treatment.The application of organic manure in maize season significantly increased the fresh ear yield of maize compared with a single application of chemical fertilizer,but the difference between them was not significant.The annual yield of wheat and maize under SS+OM treatment was the highest,reaching 19 145 kg/ha.In summary,under the conditions of this experiment,the combination of SS,NT and organic fertilizer application could significantly improve the physical properties of the soil,and the content of alkali-hydrolyzable nitrogen and available phosphorus also had a certain degree of improvement,and SS+OM treatment was beneficial to the increase of the yield of wheat-maize continuous cropping field in the Loess Plateau.

Key words: Annual yield of wheat and maize, Farming measures, Fertilization method, Soil bulk density, Soil three phase ratio, Quick-acting nutrients