Ma Peng, Fan Ping, Yang Zhiyuan, Sun Yongjian, Ma Jun
School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang 621000, China.
Rice Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu 611130, China.
Plants (Basel). 2022 Aug 25;11(17):2209. doi: 10.3390/plants11172209.
To explore the impact of nitrogen (N) rate during the wheat season and N fertilizer management during the rice season on carbon and soil nutrient pools in paddy soil, a wheat-rice rotation system for 2 successive years was implemented. In the rotation system, a conventional N rate (Nc; 150 kg/ha) and a reduced N rate (Nr; 120 kg/ha) were applied in the wheat season. Based on an application rate of 150 kg/hm N in the rice season, three N management models were applied, in which the application ratio of base:tiller:panicle fertilizer was 20%:20%:60% in treatment M1, 30%:30%:40% in treatment M2, and 40%:40%:20% in treatment M3. Zero N was used as the control (M0). Experimental results indicate that, under Nc, the M2 management model during the rice season, improvements were seen in paddy soil urease, organic carbon, and annual yield relative to other conditions. The average organic matter and total N associated with the M2 rice management model and conventional N application during the wheat season were 5.13% and 4.95% higher, respectively, relative to the use of a reduced N application rate during the wheat season. Similarly, the average total carbon content and annual yields were 6.61% and 5.56% higher under the model M2 with conventional N application during the wheat season, respectively, relative to reduced N application after the two-year study period. These findings indicate that production and carbon fixation in paddy fields can be optimized through a conventional N application rate during the wheat season, and an M2 N management model during the rice season in southern China under a wheat-rice rotation system.
为探究小麦季施氮量和水稻季氮肥管理对稻田土壤碳和土壤养分库的影响，实施了连续两年的稻麦轮作系统。在轮作系统中，小麦季施用常规施氮量（Nc；150千克/公顷）和减氮量（Nr；120千克/公顷）。基于水稻季150千克/公顷的施氮量，应用了三种氮肥管理模式，其中基肥：分蘖肥：穗肥的施用比例在处理M1中为20%：20%：60%，在处理M2中为30%：30%：40%，在处理M3中为40%：40%：20%。不施氮作为对照（M0）。实验结果表明，在常规施氮量下，相对于其他条件，水稻季的M2管理模式使稻田土壤脲酶、有机碳和年产量有所改善。与小麦季减氮施用相比，小麦季常规施氮且水稻季采用M2管理模式时，平均有机质和全氮含量分别高出5.13%和4.95%。同样，在两年研究期后，小麦季常规施氮且采用M2模式时，平均总碳含量和年产量分别比减氮施用高出6.61%和5.56%。这些研究结果表明，在中国南方稻麦轮作系统下，通过小麦季常规施氮量和水稻季M2氮肥管理模式可优化稻田生产和碳固定。
