Abstract: This study took Medicago sativa as the research object to explore the impacts of irrigation and biochar application on the actual production benefits of Medicago sativa from the perspective of nutritional quality and economic benefits. Four irrigation gradients （W₁ reduction of 30%： 450 mm， W₂ reduction of 15%： 550 mm， W₃ conventional irrigation gradient ： 650 mm， W₄ increment of 15%： 750 mm） and two biochar application levels （C₀：0 t·ha^-1，C₂：20 t·ha^-1） were set to determine the nutrient quality and annual hay yield of Medicago sativa and screen the best irrigation amount and biochar application amount. The results showed that under the condition of biochar application， the crude protein content of Medicago sativa showed an increasing trend， the neutral detergent fiber was significantly lower than that under C₀ treatment， and the dry matter intake rate and relative feeding value were significantly improved. The annual yield in W₂C₂ treatment was significantly higher than that in W₂C₀ treatment， superior to other treatments， and the annual net profit was the best， 22 422.93 CNY·ha^-1， which was 2148.53 CNY·ha^-1 higher than W₃C₀. Comprehensive evaluation showed that W₂C₂ treatment was the optimal irrigation and biochar application scheme to achieve the synergistic improvement of Medicago sativa yield， quality and economic benefits.

Key words: Medicago sativa, Biochar, Irrigation volume, Nutritional quality, Economic performance

摘要： 本研究以紫花苜蓿（Medicago sativa）为研究对象，从营养品质与经济效益的角度出发，探究灌溉量与生物质炭施用对紫花苜蓿实际生产效益的影响。本研究通过设置4个灌溉梯度（W₁减量30%：450 mm、W₂减量15%：550 mm、W₃常规灌溉梯度：650 mm、W₄增量15%：750 mm）与2个生物质炭施用水平（C₀：0 t·ha^-1，C₂：20 t·ha^-1），测定不同灌溉与生物质炭施用梯度下紫花苜蓿营养品质与年干草产量，筛选能有效提高紫花苜蓿营养品质与经济效益的最佳灌溉量与生物质炭施用量。结果表明：生物质炭施用条件下，紫花苜蓿粗蛋白含量呈增长趋势，中性洗涤纤维较C₀处理显著下降，干物质采食率与相对饲喂价值均有显著提高。W₂C₂处理年产量较W₂C₀处理显著增加，且优于其他各处理，其年净利润为各处理最佳，为22 422.93 CNY·ha^-1，较W₃C₀提高2148.53 CNY·ha^-1。综合评估表明，W₂C₂处理是实现紫花苜蓿产量、品质与经济效益协同提升的最优灌溉与生物质炭配施方案。

关键词: 紫花苜蓿, 生物质炭, 灌溉量, 营养品质, 经济效益