长期施肥红壤及其有机无机复合体非交换性钾释放动力学  

The Release Kinetics of Non-Exchangeable Potassium in Red Soil and Its Organo-Mineral Complex of Long-Term Fertilizer Experiments

作　　者：岳龙凯 王伯仁[1,2] 黄庆海[3] 柳开楼[3] 蔡泽江[1,2] 李冬初[1,2] 黄晶[1,2] 张会民[1,2] 

机构地区：[1]中国农业科学院农业资源与农业区划研究所/耕地培育技术国家工程实验室,北京100081 [2]祁阳农田生态系统国家野外科学观测研究站,湖南祁阳426182 [3]江西省红壤研究所/国家红壤改良工程技术研究中心,江西进贤331717

出　　处：《中国农业科学》2015年第23期4748-4758,共11页Scientia Agricultura Sinica

基　　金：国家自然科学基金(41371293;41071200);国家"973"计划(2011CB100501);国家公益性行业(农业)科研专项(201203030)

摘　　要：【目的】研究长期不同施肥土壤及复合体中非交换性钾释放动力学特征,深入探索长期不同施肥引起的土壤供钾能力差异,明确不同施肥土壤及其有机无机复合体中非交换性钾的供应能力。【方法】以持续20年以上的进贤和祁阳旱地长期试验为研究基础,采用超声波打散,虹吸管法分离土壤<2、2—10、10—50、50—100、>100μm粒级有机无机复合体,制备钙饱和样品,通过草酸连续浸提,得到原土及不同粒级有机无机复合体非交换性钾释放量并建立动力学方程,探索非交换性钾释放规律。【结果】浸提300 h,土壤非交换性钾累积释放量变化表现为进贤试验点化学氮、磷、钾肥与有机肥配施(NPKM)处理和化学氮、磷、钾肥配施(NPK)处理较化学氮、磷肥配施(NP)处理分别增加98.0和81.0 mg·kg-1,增加率分别为30.7%和25.4%;祁阳试验点NPKM和NPK较NP处理分别增加130.0和40.0 mg·kg-1,增加率分别为52.1%和16.0%。施用钾肥较不施钾肥显著增加<2μm粒级复合体非交换性钾累积释放量。采用一级动力学方程和Elovich方程对土壤及复合体非交换性钾释放特性进行拟合均达到极显著水平(P<0.001),同时一级动力学方程a值、Elovich方程b值均与非交换性钾释放量呈极显著正相关(P<0.001)。【结论】红壤长期施用钾肥及其配施有机肥提高土壤非交换性钾供应能力,这种能力的变化主要集中在<2μm粒级复合体;一级动力学方程a值和Elovich方程b值可以很好地模拟土壤及复合体非交换性钾的释放能力。【Objective】The objective of this study is to research the non-exchangeable potassium release characteristics in red soil and its complex of different long-term fertilizers, to explore the differences of potassium supply capacity of soil caused by long-term different fertilization, and to clarify non-exchangeable potassium（K） release ability in bulk soils and different size fractions of organo-mineral complex. 【Method】The experiment was based on two fertilization experiments of over 20 years, one of which was located at Jinxian, Jiangxi Province and the other at Qiyang, Hunan Province. Organo-mineral complexes were separated from bulk soil with the fraction sizes of 2, 2-10, 10-50, 50-100 and 100 μm by the ultrasonic beating and siphon method. The non-exchangeable K release from bulk soil and its organo-mineral complex samples were extracted using oxalic acid. Before extracting, the bulk soil and its organo-mineral complex samples were calcium saturated, and the data of the accumulation of non-exchangeable K release from bulk soil and its organo-mineral complex were used to simulate a kinetics equation to study the law of non-exchangeable K release.【Result】After 300 hours of extraction, the accumulation of non-exchangeable K release showed that at the Jinxian site, the amount of non-exchangeable K released by soil with mixed utilizing chemical nitrogen, phosphorus and potassium fertilizer combined with manure（NPKM） and mixed utilizing chemical nitrogen, phosphorus, and potassium fertilizer（NPK） increased by 98.0 and 81.0 mg·kg-1 compared with mixed utilizing chemical nitrogen and phosphorus（NP）, respectively, with the increase ratio was 30.7% and 25.4%, respectively. However, at the Qiyang site, the amount of non-exchangeable K release by NPKM and NPK increased by 130.0 and 40.0 mg·kg-1 compared with NP, respectively, and the increase ratio was 52.1% and 16.0%, respectively. The application of K fertilizer increased the accumulation of non-exchangeable K release significantly, especi

关 键 词：长期施肥 红壤 有机无机复合体 非交换性钾 动力学 

分 类 号：S158[农业科学—土壤学]