小麦-玉米种植制度下长期施钾对土壤钾素Q/I关系的影响  

Effects of long-term potassium application on Q/I relationship of potassium in soil under wheat-corn cropping system

作　　者：张会民[1,2] 徐明岗[2] 王伯仁[2] 黄绍敏[3] 杨学云[4] 

机构地区：[1]河南科技大学农学院,河南洛阳471003 [2]农业部作物营养与施肥重点开放实验室,中国农业科学院农业资源与农业区划研究所,北京100081 [3]河南农业科学院土壤肥料研究所,河南郑州450002 [4]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《植物营养与肥料学报》2009年第4期843-849,共7页Journal of Plant Nutrition and Fertilizers

基　　金：国家“十一五”重点科技支撑计划项目(2006BAD05B09、2006BAD02A14);基础性工作专项项目(2007FY220400);河南科技大学博士科研启动基金资助

摘　　要：为评价长期施肥条件下土壤钾素容量和强度（Q/I）关系,采用Q/I法研究了小麦—玉米种植制度下3类土壤（土、潮土和红壤）,连续15年不施钾（NP）和施钾（NPK）土壤钾素Q/I关系的变化及其参数与土壤性质变化的关系。结果表明,长期施钾土壤K＋平衡活度比（AR0）、土壤活性钾（KL）、非专性吸附钾（-△K0）和专性吸附钾（KX）均较不施钾土壤的高,其中,施钾后AR0和-△K0值提高幅度最大的是红壤,分别提高13.78和12.17倍;15年连续施用钾肥对红壤钾位缓冲容量（PBC）影响不明显,塿土和潮土长期施钾处理PBC值显著降低（17%～20%）。不施钾土壤K＋和Ca2＋＋Mg2＋交换自由能（-△G）（13.69～19.33 kJ/mol）高于施钾土壤（12.15～12.81 kJ/mol）;土壤钾素Q/I参数与土壤1 mol/L HNO3浸提钾、K＋饱和度和有机质含量等存在显著相关关系。土壤钾素Q/I参数能科学评价土壤的供钾状况。连续15年施钾肥土壤供钾能力较高,长期不施钾肥土壤钾素亏缺明显,尤其是潮土和红壤易出现缺钾。Quantity/intensity （Q/l） relationship of potassium （K） in soil was evaluated under a long-term K fertilization experiment. Soil samples collected from the NP and NPK treatments in the three soils （manural loess soil, fluvo-aquic soil and red soil） were analyzed for revealing the Q/I relationship of K, and the relationships between Q/I parameters and soil properties using Q/I approach under a 15 year wheat-corn cropping system. The values of K^＋ equilibrium activity ratio （AR0）, soil labile K （KL）, non-specific K （ - ΔK0）, and specific K （Kx） in the NPK treatments are larger than those in the NP treatments. The ARo and - ΔK0 values in the NPK treatments are 13.78 and 12.17 times larger than those in the NP treatments in red soil. The potential buffering capacity （PBC） is decreased （ranging from 17% to 20% ） in the NPK treatments in manural loess soil and fluvo-aquic soil, and is not changed in red soil compared with those in the NP treatments. Free energies of K^＋ exchange for Ca^2＋ and Mg^2＋ （ - ΔG） in the treatments with K fertilization are lower than those in the treatments without K application （12.15-12.81 vs 13.69-19.33 kJ/mol）. There are significant correlations between the Q/I parameters and the 1 mol/L HNO3 extractable K, K^＋ saturation and soil organic matter. The Q/I parameters provide useful information for understanding the soil K status. Soil K supplying power is increased due to the long-term K fertilization, while, continuous cropping without K inputs could cause the remarkable depletion of available K especially in the fluvo-aquic soil and red soil.

关 键 词：小麦—玉米 长期施钾 红壤 潮土 塿土 Q/I关系 

分 类 号：S158[农业科学—土壤学]