[目的]化肥配施生物炭是提高作物氮肥利用率(NUE)的重要措施之一,但作物的氮肥利用率受地域、土壤理化性质、氮肥施用量、生物炭性质及其用量等因素影响,而目前关于生物炭对氮肥利用率的研究主要局限于某一条件下进行,缺乏系统分析和比较。本研究通过比较不同土壤及量化生物炭施用量等条件探究生物炭对作物氮肥利用率的影响,为科学配施生物炭、提高氮肥利用率提供理论参考。[方法]本研究收集了符合筛选标准的文献33篇,建立了170组包含生物炭配施化肥(BC+NPK)和单施化肥(NPK)处理的氮肥利用率的数据,采用整合分析(Meta-analysis)研究不同区域氮肥利用率在NPK和BC+NPK处理下的差异。[结果]施用生物炭可以提高作物氮肥利用率约4.76%,其中南方地区提高效果最明显。土壤偏酸、养分缺乏的南方地区应增施钾、磷肥及配施生物炭以提高作物氮肥利用率；土壤养分肥沃的东北地区应控制氮肥施用量以实现氮肥效应的最大化。生物炭施用量应控制在1~3%,且氮肥施用量≤120 kg.hm-2时,生物炭的增效效果最明显。木质材料制备的生物炭可提升氮肥利用率7.99%；生物炭含氮量>2%时氮肥利用率可增效19.43%；生物炭pH 9~10时氮肥利用率最佳且提升5.01%。生物炭对粮食作物增效效果优于经济作物,大田试验增效效果优于盆栽试验。[结论]东北地区应减施有机肥、氮肥,南方地区应提高土壤pH、增施钾、磷肥,生物炭和氮肥的施用量要因地制宜以充分发挥生物炭对氮肥利用率的增效作用。同时,制备生物炭应综合考虑原材料种类、生物炭性质及其含氮量等因素选择最佳的制备材料。
[Objective] Combined application of chemical fertilizer and biochar is one of the important procedures to improve the nitrogen fertilizer utilization rate (NUE) of crops, but the nitrogen fertilizer utilization rate of crops is affected by factors such as region, soil properties, biochar properties, and biochar and nitrogen fertilizer application rates. Since most of the current research is only carried out under certain conditions, the impact of biochar on the utilization rate of nitrogen fertilizer is a lack of systematic analysis and comparison. Therefore, this article explores the impact of biochar on nitrogen fertilizer utilization, quantifies the impact of biochar on crop nitrogen fertilizer utilization under different soil and biochar application rates, and guides the use of biochar to provide an important basis for improving nitrogen fertilizer utilization. [Method] In this study, 33 publicly published documents were collected, and 170 sets of nitrogen fertilizer utilization data including biochar combined with chemical fertilizer (NPK+BC) and single chemical fertilizer (NPK) treatment were established, and integrated analysis (Meta- analysis) to study the differences in nitrogen use efficiency in different regions under NPK and NPK+BC treatments. [Result] Generally speaking, the application of biochar can improve the nitrogen fertilizer utilization rate of crops, which is increased by about 4.76%. Among them, the effect of increasing nitrogen fertilizer utilization rate in the southern region is the most obvious. In the southern regions with acid soils and nutrient deficiency, the application of potassium and phosphate fertilizers should be increased in conjunction with biochar to improve the nitrogen fertilizer utilization rate of the crops; in the northeast region of fertile nutrients, the application of nitrogen and organic fertilizers should be controlled to maximize the effect of nitrogen fertilizers. The application rate of biochar should be controlled at about 1~ 3%. When the application amount of nitrogen fertilizer is less than 120kg.hm-2, the synergistic effect of biochar is the most obvious. Secondly, in terms of physicochemical properties of biochar, biochar made from wood materials can increase the nitrogen fertilizer utilization rate by 7.99%; when the nitrogen content of biochar > 2%, the synergistic effect of nitrogen fertilizer utilization rate reaches 19.43%; the biochar pH is From 9 to 10, the increase in nitrogen fertilizer utilization rate is the most obvious, reaching 5.01%. Finally, the synergistic effect of food crop biochar is better than that of economic crops, and the synergistic effect of field trials is better than pot experiments. [Conclusion] The application of organic fertilizers and nitrogen fertilizers should be reduced and the cultivation of nutrients should be controlled in the northeast region where nutrients are distributed; in the southern regions with poor nutrients, attention should be paid to increase the pH of the soil and increase the application of potassium and phosphate fertilizers to more effectively use biochar For the synergistic effect of nitrogen fertilizer utilization rate and the effect of increasing yield and efficiency, the application amount of biochar and nitrogen fertilizer should be formulated according to the local soil properties. Secondly, for the selection of biochar, we should pay attention to comprehensive factors such as raw materials, application amount and nitrogen content, and select the best preparation materials.