饲用玉米氮素分配与根系特征对不同生物炭施加深度的响应  

Response of nitrogen distribution and roots of forage maize to biochar application at different depths

作　　者：陈泽林 林逸帆 陈国豪 刘琪琪 刘鹏[1] 张志新[1] 何学青 CHEN Zelin;LIN Yifan;CHEN Guohao;LIU Qiqi;LIU Peng;ZHANG Zhixin;HE Xueqing(College of Grassland Agriculture,Northwest A&F University,Yangling 712100,Shaanxi,China)

机构地区：[1]西北农林科技大学草业与草原学院,陕西杨凌712100

出　　处：《草业科学》2024年第1期143-150,共8页Pratacultural Science

基　　金：国家自然基金青年项目(32001403);国家自然科学基金项目(32160761)。

摘　　要：施用氮肥是当前饲草生产中提高产量的主要方式,而过量施氮会增加养分淋溶,产生环境问题。生物炭近年来已被用作新型土壤改良剂来缓/控释氮肥并见初效,而生物炭施用方式尚待优化,不同深度施用生物炭对土壤氮素和植株氮素分配的影响仍需进一步分析。本研究以不施生物炭为对照,设0-20、20-40、40-60 cm施用深度处理开展野外盆栽试验。结果表明,与其他处理相比,表施(0-20 cm)生物炭更有利于生物量提升,可有效提高总生物量19.3%,果实生物量较对照高出24.6%(P<0.05);在氮素积累方面,0-20 cm施加生物炭处理玉米(Zea mays)地上部分氮含量提升29.9%,果实以及叶鞘部分氮含量显著高于对照(P<0.05),两部分分别高出29.7%、42.3%,氮素积累情况与生物量提升情况一致;在土壤氮固持方面,0-20 cm施加深度下土壤硝态氮含量高于其余处理,而适度增加施用深度(20-40 cm)更利于土壤铵态氮固持。各生物炭施用深度处理均能促进根系生长,20-40 cm施加深度下总根长显著长于对照(P<0.05),0-20 cm施加深度下总根表面积高于对照,高出49.1%,总根体积高出215.1%(P<0.05)。因此,生物炭施用深度0-20 cm能通过明显改善根系生长从而增加地上部分氮素积累,改善土壤硝态氮固持能力,提高饲用玉米产量。研究结果为饲用玉米养分管理和生物炭合理利用提供了科学依据。Application of nitrogen fertilizer is the main way to increase yield in forage production.However,excessive nitrogen application can increase nutrient leaching and cause environmental problems.In recent years,biochar has been used as a new soil amendment to slow and control the the release of nitrogen fertilizer which has achieved some initial effect.However,the application methods for biochar need to be optimized.The effects of biochar application at different depths on soil nitrogen and plant nitrogen distribution require further analysis.In this study,no biochar was used as the control,and 0-20,20-40,and 40-60 cm deep treatments were set up to conduct field pot experiments.The results showed that compared with other treatments,surface application of biochar(0-20 cm)was more conducive to the increase of biomass,which could effectively increase the total biomass by 19.3%.The fruit biomass was 24.6%higher than that of the control treatment(P<0.05).In terms of nitrogen accumulation,the nitrogen content of the aboveground component of maize(Zea mays)increased by 29.9%.The nitrogen content of the fruit and leaf sheath was significantly higher than that of the control treatment(P<0.05),which was 29.7%and 42.3%higher than that of the control treatment,respectively.The nitrogen accumulation was consistent with the increase in biomass.In terms of soil nitrogen fixation,the soil nitrate nitrogen content at 0-20 cm in depth was higher than that of the other treatments.Meanwhile,a moderate increase in the application depth to 20-40 cm was more conducive to soil ammonium nitrogen fixation.All the biochar application depth treatments could promote root growth.The total root length at application at 20-40 cm in depth was significantly longer than that of the control treatment(P<0.05).The total root surface area at an application depth of 0-20 cm was 49.1%higher than that of the control treatment.The total root volume was 215.1%higher than that of the control treatment(P<0.05).Therefore,a biochar application depth of 0-20 cm c

关 键 词：饲草生产 生物炭 养分管理 氮素分配 根系形态 盆栽 雨养农业 

分 类 号：S548[农业科学—作物学]