单 位：
中国农业科学院土壤肥料研究所;西北农林科技大学资源环境学院陕西杨凌;中国农业科学院农业资源与农业区划研究所;洛阳农业高等专科学校;河南省农业科学院植物营养与资源环境研究所
关键词：
小麦—玉米;长期施钾;红壤;潮土;塿土;Q/I关系
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)(13.691~9.33 kJ/mol)高于施钾土壤(12.151~2.81 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。
译 名：
Effects of long-term potassium application on Q/I relationship of potassium in soil under wheat-corn cropping system
作 者：
ZHANG Hui-min1,2,XU Ming-gang2WANG Bo-ren2,HUANG Shao-min3,YANG Xue-yun4 (1 College of Agronomy,Henan University of Science and Technology,Luoyang 471003,China;2 Key Laboratory of Crop Nutrition and Fertilization,Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning,CAAS,Beijing 100081,China;3 Institute of Soil and Fertilizer,Henan Academy of Agricultural Sciences,Zhengzhou 450002,China;4 College of Resource and Environment,Northwest Sci-Tech University of Agriculture and Forestry,Yangling,Shaanxi 712100,China)
关键词：
wheat-corn cropping system;long-term K fertilization;red soil;fluvo-aquic soil;manural loess soil;Q/I relationship
摘 要：
Quantity/intensity(Q/I) 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(-△K0),and specific K(KX) in the NPK treatments are larger than those in the NP treatments.The AR0 and-△K0 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 fluvoaquic soil,and is not changed in red soil compared with those in the NP treatments.Free energies of K+ exchange for Ca2+ and Mg2+(-△G) 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.
