Zhu Hao-Yu, Gao Ming, Long Yi, Xu Guo-Xin, Wang Fu-Hua, Wang Zi-Fang
College of Resources and Environment, Southwest University, Chongqing 400715, China.
Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China.
Huan Jing Ke Xue. 2020 Apr 8;41(4):1921-1929. doi: 10.13227/j.hjkx.201909153.
The reduction in chemical fertilizers combined with organic fertilizers is a national strategy to achieve environmental friendliness and maintain the quality of cultivated land. It is of great significance for the prevention and control of soil pollution and the sustainable development of agriculture. In this study, purple soil and sloping land in the Three Gorges Reservoir area was studied. The field experiment method was used to study the control, conventional fertilization, optimized fertilization, biochar (fertilizer combined with biochar), and straw under rapeseed/corn rotation mode. The effects of five treatments on soil nitrogen/phosphorus form, crop nitrogen and phosphorus content, fertilizer utilization rate, and crop yield were studied in the field (fertilizer reduction combined with straw returning). The results showed that the soil ammonium nitrogen content was the highest in the rapeseed season, which was 4.51 mg·kg. The contents of ammonium nitrogen and alkali nitrogen in the treated corn season were significantly higher than those in the rape season. The reduction in chemical fertilizers can guarantee and increase the total nitrogen content of the soil. Among them, the total nitrogen content in the rapeseed and corn seasons treated with straw was the highest (0.56 g·kg and 0.60 g·kg, respectively). The soil treated with straw in the rapeseed season had the highest available phosphorus content (0.76 mg·kg). Compared with conventional treatment, the reduction of chemical fertilizers combined with organic fertilizer did not significantly reduce the total phosphorus content of soil. The reduction of fertilization combined with organic fertilizer showed a slight increase in yield but showed the highest yield of rapeseed treated by biochar (2328 kg·hm) and the highest yield of conventionally treated maize (5838 kg·hm). However, there was no significant difference in each treatment (>0.05). Regardless of the rapeseed season or the corn season, the reduction of fertilization treatment generally improved the agronomic utilization rate of nitrogen fertilizer and phosphate fertilizer. In the purple soil area, the combination of chemical fertilizer reduction and biochar and straw returning were beneficial to improve soil nutrients, improve fertilizer utilization, and reduce the effects of nitrogen fertilizer and phosphate fertilizer application on crop yield.
减少化肥用量并结合有机肥是实现环境友好和保持耕地质量的一项国家战略。这对于土壤污染防治和农业可持续发展具有重要意义。本研究以三峡库区紫色土坡耕地为研究对象，采用田间试验方法，研究了油菜/玉米轮作模式下的对照、常规施肥、优化施肥、生物炭（肥料与生物炭结合）和秸秆还田5种处理。田间研究了5种处理对土壤氮/磷形态、作物氮磷含量、肥料利用率和作物产量的影响（化肥减量与秸秆还田结合）。结果表明，油菜季土壤铵态氮含量最高，为4.51mg·kg。处理后的玉米季铵态氮和碱解氮含量显著高于油菜季。减少化肥用量能保证并增加土壤全氮含量。其中，秸秆处理的油菜季和玉米季土壤全氮含量最高（分别为0.56g·kg和0.60g·kg）。油菜季秸秆处理的土壤有效磷含量最高（0.76mg·kg）。与常规处理相比，减少化肥用量并结合有机肥并没有显著降低土壤全磷含量。减施化肥并结合有机肥处理产量略有增加，但生物炭处理的油菜产量最高（2328kg·hm），常规处理的玉米产量最高（5838kg·hm）。然而，各处理间差异不显著（>0.05）。无论油菜季还是玉米季，减施化肥处理总体上提高了氮肥和磷肥的农学利用率。在紫色土区，化肥减量与生物炭和秸秆还田相结合有利于改善土壤养分，提高肥料利用率，减少氮肥和磷肥施用对作物产量的影响。
