Wei Cuilan, Cao Bingshuai, Gao Songjuan, Liang Hao
College of Environment and Ecology, Jiangsu Open University, Nanjing 210036, China.
Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China.
Plants (Basel). 2025 May 30;14(11):1678. doi: 10.3390/plants14111678.
The co-incorporation of green manure and rice straw is commonly used to increase rice yield and improve soil fertility in paddy fields. However, the effects on nutrient uptake and utilization of rice under the synergistic interaction mechanism in the Taihu Plain of the Yangtze River Delta remain unclear. Based on field experiments, this study investigated the effects of green manure with rice straw return (GMS) under different nitrogen (N) fertilization rates on rice yield, nutrient use efficiency, and soil fertility. The results revealed that green manuring significantly increased rice yield while improving the uptakes and use efficiencies of N, phosphorus (P) and potassium (K). Green manure (GM) with 40% N fertilizer reduction (GM_N60) maintained the grain and straw yields and nutrient uptakes compared to winter fallow with 100% conventional N application (WF_N100). The N recovery efficiency in GM_N60 reached 45.52%, increasing by 41.26% compared to WF_N100. Rice yield and K uptake in the GMS with 40% N fertilizer reduction treatment (GMS_N60) was 10,058 and 15.41 kg/hm, increasing by 14.43% and 9.43% compared to winter fallow with rice straw return and 100% conventional N (WFS_N100). The N, P and K agronomic efficiencies in GMS_N60 increased by 77.04%, 50.22%, and 50.22% compared to WFS_N100, respectively. These findings indicate that rice straw return enhances the fertilizer-saving and yield-increasing effects of GM, promotes rice K uptake and improves P and K use efficiencies. The GM treatment increased the soil organic matter (SOM), total potassium (TK), ammonium nitrogen (NH-N) and nitrate nitrogen (NO-N) contents. Among the soil fertility indicators, TK and SOM were the most important factors influencing rice yield and N uptake. In conclusion, GMS can maintain or increase rice yield with 40% N fertilizer reduction, improve nutrient use efficiencies, and increase the reuse of rice straw, thereby supporting green and efficient rice production in the southern Jiangsu paddy area.
绿肥与稻草共施常用于提高稻田水稻产量和改善土壤肥力。然而，在长江三角洲太湖平原协同作用机制下，对水稻养分吸收和利用的影响仍不清楚。基于田间试验，本研究调查了不同施氮量下绿肥与稻草还田（GMS）对水稻产量、养分利用效率和土壤肥力的影响。结果表明，绿肥显著提高了水稻产量，同时提高了氮、磷、钾的吸收和利用效率。与冬闲田100%常规施氮（WF_N100）相比，减少40%氮肥的绿肥（GM_N60）保持了稻谷和稻草产量以及养分吸收。GM_N60的氮素回收效率达到45.52%，比WF_N100提高了41.26%。减少40%氮肥处理的GMS（GMS_N60）的水稻产量和钾吸收量分别为10058 kg/hm和15.41 kg/hm，比冬闲田稻草还田且100%常规施氮（WFS_N100）分别提高了14.43%和9.43%。与WFS_N100相比，GMS_N60的氮、磷、钾农学效率分别提高了77.04%、50.22%和50.22%。这些结果表明，稻草还田增强了绿肥的节肥增产效果，促进了水稻对钾的吸收，提高了磷和钾的利用效率。绿肥处理增加了土壤有机质（SOM）、全钾（TK）、铵态氮（NH-N）和硝态氮（NO-N）含量。在土壤肥力指标中，TK和SOM是影响水稻产量和氮吸收的最重要因素。总之，GMS可以在减少40%氮肥的情况下保持或提高水稻产量，提高养分利用效率，增加稻草的再利用，从而支持苏南稻区绿色高效水稻生产。
