Abstract: This study aimed to investigate the effect of biochar on soil nutrients，crop yield and nitrogen use efficiency in fluvo‑aquic soil. Five treatments［no fertilization and no biochar（CK），conventional fertilization（B0），and low amount of biochar（B7.5，7 500 kg/ha），medium amount of biochar（B15，15 000 kg/ha）and high amount of biochar（B22. 5，22 500 kg/ha）］were set up to study the effects of biochar on wheat yield and nutrient uptake in fluvo‑aquic soil，and soil nutrient content in 0—15 and 15—30 cm soil layers. The results showed that，biochar had significant effect on soil nutrient content，wheat yield and nitrogen use efficiency.The content of organic carbon，total nitrogen and available potassium in the 0—15 and 15—30 cm soil layers increased with the increase of biochar dosage；the content of soil available phosphorus in the 0—15 and 15—30 cm soil layers reached the maximum under B15 treatment，which were increased by 29.35% and 19.92% compared to the B0 treatment，respectively.With the increase of biochar dosage，wheat yield，1 000‑grain weight and number of grains per ear increased first and then decreased，and the B15 treatment reached the maximum. Compared with the B0 treatment，the average yield and 1 000‑grain weight in 2018—2019 increased by 31.05% and 6.44%，respectively，and the number of grains per ear increased by 3.55.At the same time，nitrogen agronomic efficiency and nitrogen use efficiency also increased first and then decreased with the increase of biochar dosage，the nitrogen agronomic efficiency increased by 6.88 kg/kg and nitrogen use efficiency increased by 21.77 percentage points respectively compared with B0 treatment. In summary，appropriate amount of biochar can increase soil carbon and nitrogen storage and available nutrients content. In order to achieve high yield of wheat，the optimum biochar application rate was 15 000 kg/ha.

摘要： 为探讨生物炭对潮土土壤养分、作物产量及氮肥利用率的影响，设置不施肥不施生物炭（CK）、常规施肥（B0）、低量生物炭（B7.5，7 500 kg/hm²）、中量生物炭（B15，15 000 kg/hm²）和高量生物炭（B22.5，22 500 kg/hm²）5个处理，研究生物炭对潮土小麦产量和养分吸收，以及0~15、15~30 cm土层土壤养分含量的影响。结果表明，生物炭对土壤养分含量、小麦产量及氮肥利用率有显著影响。0~15、15~30 cm土层有机碳、全氮及有效钾含量均随生物炭用量增加而增加；0~15、15~30 cm土层土壤有效磷含量均以B15处理最大，较B0处理分别提高29.35%、19.92%。随生物炭用量的增加，小麦产量、千粒质量、穗粒数均呈先增后减趋势，以B15 处理最大，2 a（2018—2019 年）平均产量、千粒质量较B0 处理分别提高31.05%、6.44%，穗粒数增加3.55粒。同时，氮肥农学效率和氮肥利用率均随生物炭用量的增加呈先增加后降低趋势，B15处理较B0 处理氮肥农学效率提高6.88 kg/kg，氮肥利用率提高21.77个百分点。综上，适量生物炭能够增加土壤碳氮储量、有效养分含量。为实现小麦高产，生物炭施用量以15 000 kg/hm²为最佳。

关键词: Biochar, Fluvo?aquic soil, Soil nutrients, Wheat, Yield, Nitrogen use effciency