Abstract: To mitigate drought stress and control soil erosion in the Loess Plateau in China,a field experiment was conducted by split-plot design to determine the effects of biochar application patterns and tillage practices on soil moisture,runoff,loss of sediment,nutrients,fodder yield,and water use efficiency of alfalfa. In this experiment,biochar application patterns (biochar application and no biochar application) were the main plots,and tillage practices (tied-ridging,open-ridging,and flat planting) were the split-plots. Compared to flat planting,runoff,the loss of sediment,total nitrogen,total phosphorus,and organic matter in the practices of open-ridging and tied-ridging decreased by 20.1%~37.7% and 60.1%~64.7%,54%~75.5% and 77.1%~87.6%,44.4%~65.5% and 49.0%~81.8%,36.7%~75.3% and 48.6%~87.3%,and 48.2%~72.9% and 58.6%~85.4%,respectively. Soil water storage,fodder yield,and water use efficiency of alfalfa in open-ridging and tied-ridging increased by 39.5~52.1 and 31.2~60.5 mm,26.2%~31.7% and 26.5%~35.2%,and 10.07~14.86 and 12.14~16.55 kg·hm^-2·mm^-1,respectively,during the alfalfa growing season in 2019 and 2020. Compared to no biochar application,runoff,the loss of sediment,total nitrogen,total phosphorus,and organic matter in biochar application decreased by 48%~69%,94%~125%,12%~24%,28%~46%,and 35%~48%,respectively,while soil water storage,fodder yield,and water use efficiency of alfalfa increased by 42.93~26.09 mm,106%~111%,and 1.96~6.90 kg·hm^-2·mm^-1,respectively. The tillage practice of tied-ridge-furrow rainwater harvesting combined with biochar application was found to be an effective practice for controlling soil erosion and enhancing alfalfa fodder yield in this region.

Key words: Biochar application pattern, Tillage practice, Runoff, Water loss and soil erosion, Nutrient loss, Slopping land

摘要： 为缓解我国黄土高原区干旱胁迫和控制水土流失，本研究采用裂区设计，生物炭施加模式(生物炭施加和无生物炭施加) 为主区，耕作模式(打结垄、开敞垄和平作) 为副区，研究不同生物炭施加模式和耕作模式对土壤水分、径流、泥沙流失、养分流失、紫花苜蓿(Medicago sativa L.)干草产量和水分利用效率的影响。试验结果表明，在2019和2020年紫花苜蓿生育期，与平作处理相比，开敞垄和打结垄处理的径流量、泥沙、全氮、全磷、有机质流失量分别减少20.1%~37.7%和60.1%~64.7%，54%~75.5%和77.1%~87.6%，44.4%~65.5%和49.0%~81.8%，36.7%~75.3%和48.6%~87.3%，48.2%~72.9%和58.6%~85.4%，土壤贮水量、紫花苜蓿干草产量和水分利用效率分别增加39.5~52.1和31.2~60.5 mm，26.2%~31.7%和26.5%~35.2%，10.07~14.86和12.14~16.55 kg·hm^-2·mm^-1。与无生物炭施加处理相比，生物炭施加处理的径流量、泥沙、全氮、全磷和有机质流失量分别减少48%~69%，94%~125%，12%~24%，28%~46%和35%~48%，土壤贮水量、紫花苜蓿干草产量和水分利用效率分别增加42.93~26.09 mm，106%~111% 和1.96~6.90 kg·hm^-2·mm^-1。本研究表明,生物炭施加打结垄沟集雨种植是该区域适宜耕作模式。

关键词: 生物炭添加模式, 耕作模式, 径流, 水土流失, 养分流失, 坡地