Liang Tao, Zhao Jing-Kun, Li Hong-Mei, Wang Yan, Cao Zhong-Hua, Zhang Wu-Shuai, Wang Xiao-Zhong, Guo Chao-Yi, Shi Xiao-Jun, Chen Xin-Ping
Chongqing Academy of Agricultural Sciences, Chongqing 401329, China.
Chongqing Agro-Tech Extension Station, Chongqing 401120, China.
Huan Jing Ke Xue. 2024 Jan 8;45(1):364-375. doi: 10.13227/j.hjkx.202211280.
In this study, we sought to quantify the effect of planting structure change on fertilizer input and environmental cost in Chongqing and develop scientific and rational strategies for chemical fertilizer reduction. Based on the crop fertilizer quota standard and large sample farmer survey data under the medium productivity level in Chongqing, we evaluated and analyzed the application reduction potential and environmental benefits of fertilizer with the difference method and life cycle assessment. The results showed that:① since Chongqing became a municipality directly under the central government (1997), Chongqing crop planting structure had greatly changed, and the proportion of food crop (rice, corn, wheat, bean, and potato) decreased by 21%. The area of fruits and vegetables increased from 3.36×10 hm to 1.05×10 hm, and their proportion increased by 20%. ② Nearly 55% of fertilizers had been consumed by vegetable (37%) and citrus production systems, and 11%, 12%, and 12% of fertilizers were consumed by rice, corn, and potato, respectively. ③ The total fertilizer reduction of the Chongqing planting industry could reach up to 1.69×10 tons during the period of "the 14th Five-Year Plan," with a fertilizer reduction potential of 18.6%. The fertilizer reduction potential (reduction amount) of rice, corn, citrus, and vegetables would reach 0.3% (2.9×10 tons), 12% (1.45×10 tons), 21% (3.65×10 tons), and 30% (1.18×10 tons), respectively. On the other hand, the rape system was insufficient in phosphorus potassium fertilizers, and the corn tended to be insufficient in potash fertilizer. ④ The current production level was low, and the nitrogen loss, greenhouse gas emissions, and eutrophication potential in the planting industry of Chongqing reached 1.81×10 tons (N), 1.43×10 tons (CO-eq), and 1.74×10 tons (PO-eq). With the increase in the realization degree of the crop quota standard (60%-100%), the reactive nitrogen loss, greenhouse gas emissions, and eutrophication potential decreased by 14.9%-24.9%, 10.1%-16.7%, and 13.8%-23%, respectively. The structure of the planting industry in Chongqing significantly changed, the total fertilizer consumption in Chongqing tended to decline gradually, and the fertilization intensity of commercial crops stayed at a high level. The agricultural fertilizer reduction potential and the reactive nitrogen and greenhouse gas emission reduction potential were large, especially for citrus and vegetable production systems. However, it is also necessary to pay attention to insufficient corn potash fertilizer and rape phosphorus potassium fertilizer investment and carry out collaborative promotion of fertilizer reduction.
在本研究中，我们试图量化重庆种植结构变化对化肥投入和环境成本的影响，并制定科学合理的化肥减量策略。基于重庆中等生产力水平下的作物化肥定额标准和大样本农户调查数据，我们采用差异法和生命周期评估法评估并分析了化肥的减量潜力和环境效益。结果表明：①自重庆成为直辖市（1997年）以来，重庆作物种植结构发生了很大变化，粮食作物（水稻、玉米、小麦、豆类和马铃薯）的比例下降了21%。水果和蔬菜种植面积从3.36×10公顷增加到1.05×10公顷，其比例增加了20%。②近55%的化肥用于蔬菜（37%）和柑橘生产系统，11%、12%和12%的化肥分别用于水稻、玉米和马铃薯生产。③在“十四五”期间，重庆种植业化肥总减量可达1.69×10吨，化肥减量潜力为18.6%。水稻、玉米、柑橘和蔬菜的化肥减量潜力（减量幅度）分别达到0.3%（2.9×10吨）、12%（1.45×10吨）、21%（3.65×10吨）和30%（1.18×10吨）。另一方面，油菜系统磷钾肥不足，玉米钾肥趋于不足。④目前生产水平较低，重庆种植业的氮素流失、温室气体排放和富营养化潜力分别达到1.81×10吨（N）、1.43×10吨（CO₂-eq）和1.74×10吨（PO₄-eq）。随着作物定额标准实现程度的提高（60%-100%），活性氮流失、温室气体排放和富营养化潜力分别下降14.9%-24.9%、10.1%-16.7%和13.8%-23%。重庆种植业结构发生显著变化，重庆化肥总消费量呈逐渐下降趋势，经济作物施肥强度处于较高水平。农业化肥减量潜力以及活性氮和温室气体减排潜力较大，尤其是柑橘和蔬菜生产系统。然而，也需要注意玉米钾肥和油菜磷钾肥投入不足的问题，并协同推进化肥减量。
