• ISSN 1008-505X
  • CN 11-3996/S
ZHU Yun, LIAO Shi-peng, LIU Yu, LI Xiao-kun, REN Tao, CONG Ri-huan, LU Jian-wei. Differences of annual nutrient budgets between rapeseed−rice and wheat−rice rotations in the Yangtze River Basin[J]. Journal of Plant Nutrition and Fertilizers, 2019, 25(1): 64-73. DOI: 10.11674/zwyf.18031
Citation: ZHU Yun, LIAO Shi-peng, LIU Yu, LI Xiao-kun, REN Tao, CONG Ri-huan, LU Jian-wei. Differences of annual nutrient budgets between rapeseed−rice and wheat−rice rotations in the Yangtze River Basin[J]. Journal of Plant Nutrition and Fertilizers, 2019, 25(1): 64-73. DOI: 10.11674/zwyf.18031

Differences of annual nutrient budgets between rapeseed−rice and wheat−rice rotations in the Yangtze River Basin

  • Objectives The differences of annual nutrient budgets were evaluated and compared between rapeseed−rice (R-R) and wheat−rice(W-R) rotations in the Yangtze River Basin during 1990 to 2017, aiming to provide basis for improving annual nutrient use efficiency and optimizing rational distribution of nutrient resources in paddy-upland rotation systems.
    Methods Total of 513 field experiments for R-R and W-R rotations were collected, covering Sichuan, Chongqing, Guizhou, Hubei, Hunan, Jiangxi, Anhui, Jiangsu, Shanghai and Zhejiang provinces, China. The data included fertilizer rates, crop biomass, nutrient concentration, nutrient accumulation, nitrogen losses and so on, and the return of straw, stubble and litter loss were involved in crop biomass, and ammonia volatilization, nitrous oxide emissions, nitrogen leaching and runoff were involved in nitrogen losses. Then annual nutrient budgets of nitrogen (N), phosphorus (P) and potassium (K) were analyzed, and the nitrogen losses were calculated.
    Results There was no significant difference in fertilizer rates for the two rotation systems. The average annual N, P2O5, K2O rates were 378.5 kg/hm2, 169.9 kg/hm2, 225.7 kg/hm2 for the R-R rotation and 394.4 kg/hm2, 172.5 kg/hm2, 210.8 kg/hm2 for the W-R rotation. The returning biomass of R-R rotation was 18984 kg/hm2, which was higher than that of 18123 kg/hm2 in W-R rotation. The average annual N, P2O5 and K2O returning for R-R rotation were 142.5 kg/hm2, 46.4 kg/hm2 and 441.3 kg/hm2, which were 9.7%, 6.7% and 27.4% higher than those of W-R rotation, respectively. The N, P2O5 and K2O returning by litter loss accounted for 29.3%, 18.5% and 16.3% of the total nutrient returning of rapeseed, as a result, the nutrient inputs of rapeseed season were significantly higher than those of wheat season. For the rice season, nutrient inputs in the W-R rotation showed an obvious advantage (except for K) due to the large population of wheat biomass. Averaged annual N, P2O5 and K2O uptake of W-R rotation were 333.9 kg/hm2, 125.8 kg/hm2 and 379.3 kg/hm2, which were 14.6%, 2.1% and −13.4% higher than those of R-R rotation. Annual N loss from R-R and W-R rotations were respective N 96.7 and 88.8 kg/hm2, accounting for 22.5%−25.5% of the annual fertilizer N input. The N loss in rapeseed season was 34.5 kg/hm2, slightly higher than that of 29.8 kg/hm2 in wheat season, and that in rice season was N 59.0−62.2 kg/hm2, significantly higher than that in winter crops, so there was little difference between the two rotations. The highest N loss proportion (7.2%−18.4%) was from NH3 volatilization, then was from N runoff and leaching (6.7%−12.7%), and the lowest (1.1%−2.1%) was from N2O emission. When there was no straw returned, there was N surplus of 37.3 kg/hm2 in R-R rotation and −6.0 kg/hm2 in W-R rotation, P surplus of P2O5 53.3−58.4 kg/hm2 and K deficit of K2O 138.3−145.0 kg/hm2 in both the rotations. In case of straw returning to the field, the average annual nutrient budgets of R-R rotation were N 133.0 kg/hm2, P2O5 93.1 kg/hm2 and K2O 229.0 kg/hm2, which were 30.9%, 3.2% and 28.7% higher than those of W-R rotation.
    Conclusions Without straw returning, N is surplus in rapeseed-rice rotation and keeps balanced or slightly deficit in wheat-rice rotation, P is surplus and K is deficient in both rotations. With straw returning, all the N, P and K nutrients are surplus in both the rotations. Straw returning is thus an important factor for annual nutrient balance in soil. As the large amount of N returning brought by high biomass of rapeseed, N fertilizer could be minimized to some extent in rapeseed-rice rotation.
  • loading

Catalog

    Turn off MathJax
    Article Contents

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return