长期施钾及小麦秸秆还田对北方典型土壤固钾能力的影响  

Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Potassium Fixation Capacity of Selected Soils from Northern China

作　　者：谭德水[1] 金继运[2] 黄绍文[2] 刘兆辉[1] 江丽华[1] 

机构地区：[1]山东省农业科学院土壤肥料研究所,济南250100 [2]中国农业科学院农业资源与农业区划研究所,北京100081

出　　处：《中国农业科学》2010年第10期2072-2079,共8页Scientia Agricultura Sinica

基　　金：国家重点基础研究发展计划("973")项目(2007CB109306);国家科技支撑计划项目(2008BADA4B07;2007BAD87B05);国际植物营养研究所(IPNI)中国项目

摘　　要：【目的】探索在连续13年的钾肥施用及小麦秸秆还田条件下耕层土壤对外源钾素的固定能力。【方法】在各点同一氮磷用量水平上长期进行不同用量钾肥投入以及小麦秸秆还田,定位13年后对不同试验点各处理土壤样品进行不同浓度的KCL溶液浸泡处理,以研究中国北方典型土壤的固定钾素能力。【结果】长期连续施用钾肥或秸秆还田可显著降低土壤对外源钾素的固定,环境溶液中钾素浓度从1000mg·L-1上升至4000mg·L-1时,土壤固钾量亦随之增加。一年两作种植制度下土壤的固钾量较单作制高。土壤固钾能力表现出明显的地带性分布规律,自西向东土壤对钾的固定能力逐渐增强。在环境溶液中钾为1000mg·L-1浓度下,取自西北、华北和东北试验点只施氮磷肥(NP)处理土壤的平均固钾量分别为349、443和469mg·kg-1。【结论】连续耗竭及连续施钾的土壤固钾能力差异亦是判断土壤钾素状况的重要特征之一。【Objective】 Experiments were conducted to study the difference of potassium fixation capacity. 【Method】 Fixed-site researches on cultivated layer of soil under long-term application of K fertilizer and wheat straw to soil for 13 continuous years in selected regions of north China were carried out. After 13 years,soil samples of different treatments collected from each fixed-site were treated with different concentrations of KCl solution to study K fixation capacity of typical soil in northern China. 【Result】 The results showed that continuous application of K fertilizer and wheat straw could reduce the fixation rate of added K significantly,and when the concentration of K increased from 1 000 mg·L^-1 to 4 000 mg·L^-1 in the soil solution,K fixation capacity of soils increased at the same time. In the same region,K fixation rate of soils in double cropping regime was higher than that in single cropping regime. K fixation capacity of soil showed a clear increasing trend of distribution from the west to the east. When the K concentration in the surrounding solution was 1 000 mg·L^-1,the average K fixation rates of soils in NP treatment were 348.5,442.9,and 468.5 mg·kg^-1 in Northwest,North China and Northeast China,respectively. 【Conclusion】 Difference in potassium fixation rate between soils with depletion of K successively and soils supplied with K successively is an important character for judging the condition of soil potassium.

关 键 词：长期施钾 小麦秸秆还田 北方典型土壤 固钾能力 

分 类 号：S158[农业科学—土壤学]