基于红壤稻田肥力与相对产量关系的水稻生产力评估

柳开楼; 黄晶; 张会民; 韩天富; 黄庆海; 余喜初; 李大明; 胡惠文; 叶会财; 胡志华; 马常宝; 薛彦东

doi:10.11674/zwyf.18150

摘要:

目的土壤肥力是水稻产量提升的基础，研究土壤肥力质量指数与水稻产量的量化关系可以为稻田土壤培肥和产量提升提供理论参考。

方法本研究基于位于江西省南昌市进贤县的红壤稻田长期肥料定位试验和县域尺度样点调研，长期试验包括不施肥 (CK)、单施氮肥 (N)、单施磷肥 (P)、单施钾肥 (K)、氮磷肥配施 (NP)、氮钾肥配施 (NK)、氮磷钾肥配施 (NPK)、2倍氮磷钾肥配施 (2NPK) 和有机无机肥配施 (NPKM) 处理，收集1981年、1985年、1989年、1995年、2002年、2005年、2012年和2017年的土壤pH、有机质、有效磷、速效钾和水稻产量；并于2017年在进贤县布置了58个代表性点位，获取土壤pH、有机质、有效磷、速效钾和晚稻产量数据。采用Fuzzy方法对长期试验不同施肥处理的土壤肥力质量指数进行计算，构建和验证土壤肥力质量指数与水稻相对产量的量化关系，并在进贤县进行了验证。

结果在红壤性双季稻田，不同施肥处理显著影响水稻产量和土壤肥力质量指数，与CK处理相比，NPKM、2NPK和NPK处理的年平均产量分别增加了71.6%、59.1% 和36.5%；土壤肥力质量指数分别增加了64.1%、47.3% 和27.7%，且NPKM处理的水稻产量和土壤肥力质量指数分别比NPK处理增加了25.6% 和28.5%；同时，NP和NK处理的水稻产量和土壤肥力质量指数也显著低于NPKM处理，而N、P和K处理的水稻产量和土壤肥力质量指数则与CK没有显著差异。线性拟合方程发现，红壤稻田的土壤肥力质量指数增加0.1个单位，水稻相对产量增加7.2%～22.6%。县域尺度的验证结果表明，基于土壤肥力质量指数预测的水稻相对产量与实际相对产量高度吻合 (R² = 0.5268，P < 0.01，RRMSE < 25%)，表明基于土壤肥力质量指数可较准确地评估该区域的水稻生产能力。

结论在红壤稻田上，化肥配施有机肥是提升土壤肥力质量和水稻产量的关键技术途径，且利用土壤肥力质量指数与水稻相对产量的量化关系可以指导该地区的土壤培肥管理和生产力评估。

Abstract:

Objectives To study soil fertility improvement and yield based on the quantitative relationship between soil fertility index (SFI) and yield.

Methods This study is based on the long-term fertilization experiment and county-scale sample surveys of red paddy fields in Jinxian County, Nanchang City, Jiangxi Province of China. The long-term field experiment was started from 1981, which included no fertilization (CK), nitrogen fertilizer only (N), phosphate fertilizer only (P), potassium fertilizer only (K), combined nitrogen and phosphorus fertilizers (NP), combined nitrogen and potassium fertilizers (NK), combined nitrogen, phosphorus and potassium fertilizers (NPK), double the amounts of nitrogen, phosphorus and potassium fertilizers (2NPK), combined organic and inorganic fertilizers (NPKM). Then, Soil pH, organic matter, available phosphorus, readily available potassium and rice yield were measured in 1981, 1985, 1989, 1995, 2002, 2005, 2012 and 2017. Meanwhile, the soil pH, organic matter, available P, readily available K and late rice yield were also analyzed from 58 representative sites of Jinxian County in 2017. SFIs of different treatments in a long-term fertilization experiment were evaluated by the Fuzzy method in a red paddy soil and the quantitative relationship between SFI and relative yield was established and validated.

Results Different fertilization treatments affected rice yield and SFI significantly. Compared to CK, the average yield of NPKM, 2NPK and NPK were increased by 71. 6%, 59.1% and 36.5%, respectively. Their SFIs were increased by 64.1%, 47.3% and 27.7%, respectively. Compared with NPK treatment, the average yield and SFI in NPKM treatment were improved by 25.6% and 28. 5%. In contrast, the yield of NP and NK treatments and their SFIs decreased significantly. The average yield and SFI among N, P and K treatments were not significantly different from the CK. Furthermore, SFI and relative yield showed a linear relationship (P < 0.05), and the relative yield was improved by 7.2%−22. 6%, while the SFI was increased by 0.1. The validation experiment on the county scale showed that the estimated relative yield closely matched the measured values (R² = 0.5268, P < 0.01, RRMSE < 25%), suggesting that the SFI could indicate rice production on the county scale.

Conclusions Application of organic and chemical fertilizers is a key technology for improving SFI and yield in the red paddy soil. Moreover, the quantitative relationship between SFI and relative yield could guide the management of soil fertility in the red soil.

基于红壤稻田肥力与相对产量关系的水稻生产力评估

Assessment of productivity of red paddy soil based on soil fertilityand relative yield