长期不同施肥对黄壤磷素吸附–解吸特性的影响  

Effects of long-term fertilization on phosphorus adsorption and desorption characters in yellow soil

作　　者：刘彦伶[1,2] 李渝 张萌[1,2] 张雅蓉 黄兴成[1,2] 蒋太明 张文安 LIU Yan-ling;LI Yu;ZHANG Meng;ZHANG Ya-rong;HUANG Xing-cheng;JIANG Tai-ming;ZHANG Wen-an(Institute of Soil and Fertilizer,Guizhou Academy of Agricultural Sciences,Guiyang 550006,China;Scientific Observing and Experimental Station of Arable Land Conservation and Agriculture Environment(Guizhou),Ministry of Agriculture and Rural Affairs,Guiyang 550006,China;Institute of Tea Research,Guizhou Academy of Agricultural Sciences,Guiyang 550006,China)

机构地区：[1]贵州省农业科学院土壤肥料研究所,贵州贵阳550006 [2]农业农村部贵州耕地保育与农业环境科学观测实验站,贵州贵阳550006 [3]贵州省农业科学院茶叶研究所,贵州贵阳550006

出　　处：《植物营养与肥料学报》2021年第3期450-459,共10页Journal of Plant Nutrition and Fertilizers

基　　金：贵州省科学技术基金项目(黔科合基础﹝2018﹞1154);国家自然科学基金项目(32060302);贵州省农业科学院青年基金(黔农科院青年基金﹝2018﹞19号);省科技平台及人才团队计划(黔科合平台人才﹝2018﹞5604号);中央引导地方财政科技发展专项资金项目(黔科中引地﹝2019﹞4003号);贵州省科技支撑计划项目(黔科合支撑﹝2018﹞2340号)。

摘　　要：[目的]磷吸附–解吸特性对土壤磷素有效性和环境流失风险有重要影响。研究长期不同施肥对黄壤旱地磷吸附–解吸特性的影响,可为黄壤区合理施用磷肥提供理论依据。[方法]供试黄壤肥力长期定位试验位于贵阳,始于1995年。设有对照(CK)、施氮钾肥(NK)、施氮磷钾肥(NPK)、单施有机肥(M)和有机肥化肥配施(MNPK)5个处理。采用恒温平衡方法,研究了磷最大吸附量(Q_(m))、磷吸附常数(K)、磷吸附自由能(|ΔG|)、磷最大缓冲容量(MBC)、磷吸附饱和度(DPS)、磷固定量(PI)、磷解吸率(DR),不同施肥处理土壤对外源磷的吸附和解吸特征,并分析土壤磷吸附解吸特征参数与土壤理化性质之间的关系。[结果]M和MNPK处理显著降低了土壤中的黏粒含量,提高了有机质含量和pH,提高了土壤全磷和有效磷及微生物量磷含量;NK和NPK处理对土壤黏粒含量没有显著影响,但是降低了有机质和pH,NK处理降低了土壤的磷含量和有效性。Langmuir吸附等温线方程能很好地拟合土壤吸附磷和相应的平衡溶液磷浓度曲线(R^(2)为0.9532~0.9950,P<0.01)。与CK相比,NK、NPK处理Q_(m)分别显著增加了39.2%、40.9%,M处理Q_(m)显著降低了20.0%,MNPK处理Q_(m)无显著差异,说明施用化肥可增加土壤对磷素的吸附位点,而施用有机肥则减少了土壤对磷素的吸附位点,有机无机肥配施时则吸附位点无显著变化;各处理K、|ΔG|、MBC、PI表现为MNPK≤M<CK<NPK<NK,DPS则表现为MNPK>M>NPK>CK>NK,DR均值表现为MNPK>M>CK>NPK>NK。当加入外源磷浓度<10 mg/L时,NK和NPK处理的磷固液比为85.8~100.3,CK为4.2~28.8,M和MNPK处理为2.5~7.7,说明当施用的外源磷浓度较低时,长期施用化肥处理中的磷大部分被土壤吸附,难以被作物利用,而长期施用有机肥处理中磷则大部分留存在液相中,有利于作物的吸收利用。相关分析表明,Q_(m)、K、|ΔG|、MBC、PI等磷吸附特征参数与土壤黏粒含量、pH�[Objectives]The adsorption and desorption process influences the behavior of P in soil.The effect of long-term fertilization on the adsorption and desorption of soil P was studied,to provide theoretical basis of rational fertilizer application and improve the P availability of yellow soil.[Methods]Conducted between 1995 and 2016 on a yellow soil in Guiyang City,the long-term fertilization experiment consisted of five treatments:blank control(CK),no P fertilizer input(NK),NPK chemical fertilizer(NPK),manure alone(M)and NPK plus manure(MNPK).The soil physico-chemical properties were determined.Isothermal adsorption and desorption experiment was conducted to determine the maximum P adsorption capacity(Q_(m)),P adsorption constant(K),P adsorption free energy(|ΔG|),buffering capacity of soil P(MBC),P saturation degree(DPS),P immobilization amount(PI),P desorption rate(DR).[Results]Long-term fertilization treatments significantly affected soil physical and chemical properties.M and MNPK treatments significantly reduced soil clay content,increased soil organic matter content and pH,and increased soil total P,Olsen-P and microbial biomass P content.NK and NPK treatments had no significant effect on soil clay content,but decreased soil organic matter and pH.NK treatment reduced soil P content and availability.Langmuir equation was proved well to predict the absorption and desorption of P in soil(R 2=0.953–0.995;P<0.01).Compared with CK,Q_(m) of NK and NPK treatments increased by 39.2%and 40.9%,respectively,while that of M treatment decreased by 20.0%,and there was no significant difference in MNPK treatment,which indicated that chemical fertilizer application could increase the adsorption sites of soil for P,while manures application could reduce the adsorption sites,and the adsorption sites changed little when combined application of manures and chemical fertilizers;K,|ΔG|,MBC and PI were such that MNPK≤M<CK<NPK<NK,while DPS followed this order–MNPK>M>NPK>CK>NK,average of DR followed this order–MNPK>M>CK>NPK>NK

关 键 词：黄壤 长期施肥 土壤磷素 吸附 解吸 

分 类 号：S147[农业科学—肥料学]