生物质炭和Ca(OH)_(2)缓解土壤酸化过程中植物铝毒性的模拟对比研究  

Contrasting Effects of Biochar and Ca(OH)_(2) on Alleviating Plant Aluminum Toxicity during Soil Acidification:A Simulation Study

作　　者：来宏伟 倪妮 时仁勇 董颖 闫静 Nkoh Jackson Nkoh 李九玉[2] 崔秀敏[1] 徐仁扣[2] LAI Hongwei;NI Ni;SHI Renyong;DONG Ying;YAN Jing;NKOH Jackson Nkoh;LI Jiuyu;CUI Xiumin;XU Renkou(National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources,College of Resources and Environment,Shandong Agricultural University,Tai’an,Shandong 271018,China;State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;Nanjing Institute of Environmental Science,Ministry of Ecology and Environment,Nanjing 210042,China)

机构地区：[1]土肥资源高效利用国家工程实验室(山东农业大学资源与环境学院),山东泰安271018 [2]土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所),南京210008 [3]生态环境部南京环境科学研究所,南京210042

出　　处：《土壤学报》2023年第4期1017-1025,共9页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(41907019);江苏省自然科学基金项目(BK20191103,BK20190141);山东省自然科学基金项目(ZR202102220216)资助。

摘　　要：随着外源酸输入,酸性土壤改良剂的石灰效应逐渐消退,土壤再次酸化形成铝毒害。作为一种新型酸性土壤改良剂,生物质炭施用后土壤的复酸化过程尚不清楚。本研究通过循环酸浸洗耦合根伸长试验,对比研究了施用生物质炭和熟石灰(Ca(OH)_(2))后土壤的复酸化过程及其对植物的铝毒性。结果表明,循环酸浸洗有效模拟了土壤的复酸化过程。随着模拟酸化年限增加,生物质炭和Ca(OH)_(2)处理土壤中玉米根系伸长均逐渐受到了抑制。生物质炭相较于Ca(OH)_(2)有效缓解了酸化过程对植物根系的抑制作用。在模拟12年酸输入时,生物质炭处理中玉米根相对伸长率较Ca(OH)_(2)处理高18.6%,生物质炭相较于Ca(OH)_(2)处理展现出更为长效的酸性土壤改良潜力。这一方面是由于生物质炭通过表面阴离子官能团质子化作用减缓了酸化过程中土壤pH的降低,抑制了土壤铝的活化。在模拟12年酸输入时,生物质炭处理土壤溶液Al^(3+)浓度较Ca(OH)_(2)处理低33%。另一方面,酸化过程中生物质炭持续释放Mg^(2+),在模拟12年酸输入时,生物质炭处理土壤溶液Mg^(2+)浓度和植物Mg^(2+)吸收量均较Ca(OH)_(2)处理高2倍以上。较高的Mg2+浓度可通过调控植物对Al^(3+)的生理响应,缓解植物铝毒害症状。该研究结果可为土壤酸化长效阻控提供理论依据和技术支撑。【Objective】With the input of acid,the lime effect of ameliorants on acidic soils is gradually weakened resulting in soil re-acidification and aluminum toxicity.As a new alternative amendment material for acid soils,the performance of biochar on alleviating aluminum toxicity during soil re-acidification is still unclear.To investigate the effect and mechanisms of biochar on alleviating aluminum toxicity during soil acidification,a comparative study between biochar and Ca(OH)_(2)was conducted through a simulated soil re-acidification test.【Method】Cyclic acid leaching with HNO3 was used to rapidly simulate the soil acidification process.A root elongation experiment with maize was used to investigate the response of plant roots to soil acidification.The change in soil pH,soluble Al3+and base cations(K^(+),Ca2+and Mg^(2+))during soil acidification were also studied.【Result】Cyclic acid leaching effectively simulated the process of soil re-acidification.With the increase of cyclic acid leaching time,soil pH decreased and the maize root elongation was inhibited.Compared with Ca(OH)_(2)treatment,biochar significantly inhibited the acidification process and alleviated adverse effects on plant roots.When acid input was simulated for 12 years,the relative elongation of maize root in biochar treatment was 18.6%higher,and the relative absorption of Evans blue was 19.6%lower than that in Ca(OH)_(2)treatment.On the one hand,biochar slowed down the decrease of soil pH during re-acidification through the protonation of surface anionic functional groups,and thus inhibited the activation of soil aluminum.As a result,the soil pH and the soluble Al^(3+)concentration in biochar treatment were 0.12 units higher and 33%lower than that in Ca(OH)_(2)treatment with simulated 12-year acid input,respectively.On the other hand,biochar released Mg^(2+)continuously during soil re-acidification.In the simulation of 12-year acid input,the concentration of Mg^(2+)in soil solution and uptake of Mg^(2+)by maize in biochar treatment was mo

关 键 词：生物质炭 熟石灰 土壤复酸化 植物铝毒害 铝活化 盐基阳离子 

分 类 号：S153[农业科学—土壤学]