饲用燕麦养分吸收对农牧交错区土壤类型和水肥管理的响应OA

Oat(Avena sativa L.)is a major forage crops in the agro-pastoral ecotone of northern China.Its productivity is often co-limited by both water and nutrient availability,and the region is charac-terized by diverse soil types.However,the mechanisms underlying the interactive effects of soil type and water-fertilizer management on yield formation and nutrient uptake in oat remain poorly understood.Based on a soil translocation network experiment platform established across the agro-pastoral ecotone,this study investigated the effects of irrigation and fertilization on biomass and nitrogen(N)and phosphorus(P)uptake of oat grown in four typical soil types:chernozem,loessal soil,chestnut soil,and aeolian sandy soil.The results indicated that:(1)Irrigation or fertilization alone optimized aboveground biomass allocation,increased aboveground biomass,and thereby enhancing N and P uptake in oat.(2)Water-fertilizer coupling significantly increased stem and leaf biomass in all four soil types(P<0.05)and significantly increased N and P uptake in chernozem,loessal soil,and chestnut soil(P<0.05).(3)Structural equation modeling fur-ther revealed that water-fertilizer coupling enhanced the accumulation of stem and leaf biomass,which increased total aboveground biomass and consequently drove greater N and P uptake.Overall,soil type was a key factor determining oat responses to water and fertilizer management.Therefore,site-specific water and fertilizer based on soil properties and crop demands should be implemented to effectively improve oat productivity and water use efficiency in the agro-pastoral ecotone of northern China.