Zhang Qi, Wang Hao, Wang Shu-Lan, Zhang Yuan-Hong, Wang Rui, Wang Xiao-Li, Li Jun
College of Agronomy, Northwest A&F University, Yangling 712100, Shannxi, China.
Ying Yong Sheng Tai Xue Bao. 2020 Feb;31(2):459-466. doi: 10.13287/j.1001-9332.202002.024.
Straw mulching and subsoiling can protect soil and improve soil structure. However, long-term continuous subsoiling cannot continuously gain yield increasing and soil improvement. To realize continuous soil improvement and yield enhancement, a long-term experiment on subsoiling alternation patterns was carried out with spring maize continuous cropping in the Loess Plateau in 2007-2016. The subsoiling alternation patterns were no-tillage/conventional tillage/subsoiling (NT/CT/ST) and subsoiling/conventional tillage (ST/CT), with continuous subsoiling (ST) as control. We analyzed the effects of the different patterns on soil physical and chemical properties and maize yield. The results showed that, compared with the ST, the mechanical-stable aggregates (DR) and water-stable aggregates (WR) in NT/CT/ST were significantly increased by 9.2% and 21.9%, with the mean weight diameter (MWD) and geometrical mean diameter (GMD) being significantly increased. The WR in ST/CT was significantly increased by 11.9%. In 0-20 cm soil layer, soil bulk density in NT/CT/ST and ST/CT decreased by 7.0% and 11.5%, and soil porosity increased by 8.4% and 13.9%, respectively. In 20-40 cm soil layer, soil bulk density in ST/CT increased by 6.9%, and soil porosity decreased by 5.7%. In the NT/CT/ST, soil total nitrogen and organic matter contents significantly increased, but soil total phosphorus and total potassium contents reduced. The multi-year average grain yield of spring maize in NT/CT/ST was 10.2% higher than ST and 4.8% higher than ST/CT. The DR, WR, soil total nitrogen content and soil organic carbon content were all positively correlated with maize yield, indicating such changes faci-litated corn grain yield. Considering the effects on soil fertility and corn yield, the NT/CT/ST model was conducive to soil fertility, soil structural stability and higher maize yield.
秸秆覆盖和深松能够保护土壤并改善土壤结构。然而，长期连续深松并不能持续实现增产和土壤改良。为实现土壤的持续改良和产量提升，2007—2016年在黄土高原地区开展了春玉米连作条件下深松轮作模式的长期试验。深松轮作模式为免耕/常规耕作/深松（NT/CT/ST）和深松/常规耕作（ST/CT），以连续深松（ST）作为对照。分析了不同模式对土壤理化性质和玉米产量的影响。结果表明，与ST相比，NT/CT/ST模式下的机械稳定团聚体（DR）和水稳性团聚体（WR）分别显著增加了9.2%和21.9%，平均重量直径（MWD）和几何平均直径（GMD）也显著增加。ST/CT模式下的WR显著增加了11.9%。在0—20厘米土层，NT/CT/ST和ST/CT模式下的土壤容重分别降低了7.0%和11.5%，土壤孔隙度分别增加了8.4%和13.9%。在20—40厘米土层，ST/CT模式下的土壤容重增加了6.9%，土壤孔隙度降低了5.7%。在NT/CT/ST模式下，土壤全氮和有机质含量显著增加，但土壤全磷和全钾含量降低。NT/CT/ST模式下春玉米多年平均籽粒产量比ST高10.2%，比ST/CT高4.8%。DR、WR、土壤全氮含量和土壤有机碳含量均与玉米产量呈正相关，表明这些变化有利于玉米籽粒产量的提高。综合考虑对土壤肥力和玉米产量的影响，NT/CT/ST模式有利于土壤肥力、土壤结构稳定性及较高的玉米产量。
