【作者】 刘代欢；

【导师】 梁成华；

【作者基本信息】 沈阳农业大学 ， 土壤学， 2009， 博士

【摘要】 本文以长期定位施肥设施蔬菜栽培土壤为研究对象,通过恒温培养法、流动交换法、阳离子交换树脂法、连续浸提法等研究方法,分别对不同施肥处理土壤的钾素固定释放、吸附解吸动力学、非交换性钾释放、容量强度关系,不同盐分浸提的钾素释放,以及去除有机质对钾素吸附解吸动力学的影响进行了研究,结果如下:1.不施有机肥处理土壤固钾能力强,而施有机肥处理土壤的释钾能力强。固钾过程中i位钾含量的差别是施有机肥和不施有机肥处理土壤固钾能力差别的主要原因。土壤固钾量与CEC/（速效钾+缓效钾）的值呈极显著正相关,而释钾量与CEC*速效钾/（速效钾+缓效钾）的值呈正显著正相关。2.各处理间土壤K⁺吸附、解吸平衡时间和平衡吸附、解吸量差别很大。土壤CEC、粘粒、有机质和速效钾含量是影响的主要因素。描述各处理K⁺吸附解吸动力学的最优方程总体是Elovich方程,个别为一级动力学方程。长期定位施肥带来设施蔬菜栽培土壤固相表面与钾素作用特征发生改变。3.不同施肥处理土壤非交换性钾的释放量与缓效钾的含量有着极显著正相关关系。施有机肥各处理土壤的非交换性钾释放量明显大于不施有机肥的各个处理;各处理间,施有钾肥的处理土壤的非交换性钾释放量较高,而仅施氮肥处理的释放量相对较低。所有处理初始阶段（0-1h）的土壤的非交换性钾释放速率远都高于后续阶段;施有机肥处理在初始阶段的土壤的非交换性钾释放速率又远高于不施机肥处理,这或是二者土壤非交换性钾释放总量和释放速率差别的主要原因。抛物线扩散方程是描述各处理土壤的非交换性钾释放动力学过程的最佳模型,土壤非交换钾的释放是扩散控制过程。4.长期施用有机肥和施钾素化肥的处理的-ΔK⁰都较高。-ΔK⁰与CEC、速效钾及粘粒含量都达到显著或极显著正相关;施有机肥、钾肥的和施用高量氮肥的处理（AN2、BN2）的土壤ARe^K高。土壤有机质、CEC、速效钾、粘粒含量和钾素饱和度都与ARe^K呈极显著正相关;不施有机肥各处理土壤的PBC^K都为施有机肥各处理的约1～3倍,长期施用有机肥的设施蔬菜栽培土壤的PBC^K降低;所有施有钾肥处理和施用高量氮肥处理（AN2、BN2）的PBC^K较低;PBC^K值与CEC、有机质、速效钾含量呈显著负相关,而e位交换钾/p位交换钾的比值与PBC^K呈极显著正相关,是决定PBC^K大小的主要因素。5.描述H₂O和CaCl₂浸提的土壤钾素释放过程的最佳方程都是一级动力学方程;而NaCl的则为抛物线扩散方程,NH₄Cl的则是双常数方程。在施有机肥和不施有机肥处理中,单施钾肥处理（K）、磷钾配施处理（PK）用0.1MNaCl、NH₄Cl、CaCl₂,和H₂O浸提得到的钾素释放量较高,而单施氮肥处理（N1）和氮磷配施处理（NP）的则都较低;不施有机肥处理的固定态钾素有三至五成可以释放出来,施有机肥处理则不但可以把新固定的钾释放出来,还可以把原先固定的部分层间钾素释放出来。连续浸提的钾素释放量占层间钾素的比例与原先土壤理化性质中的速效钾/缓效钾的比例近似,二者呈极显著正相关。各处理土壤固定态钾用NaCl浸提的释放过程属于扩散控制过程。6.去除有机质后,描述钾素吸附、解吸的最佳动力方程基本还是Elovich方程。去除有机质会降低各方程对土样钾素吸附、解吸动力学的程拟合效果。吸附、解吸反应中,p、e、i位点都是同时参与反应,不同位点在反应中的主导地位如何应是影响动力学方程拟合程度的根本所在。通过本研究基本了解设施蔬菜栽培土壤长期（19年）定位施肥后,不同施肥处理间不同钾素供应能力指标上的各自特点和之间区别;初步明确长期不同施肥带来的土壤CEC,有机质、粘粒含量（钾素作用位点）以及土壤速效钾、缓效钾含量（钾素有效形态）的改变,是影响钾素供应能力差别的根本所在。更多还原

【Abstract】 The research took samples from greenhouse vegetable fields under long-term experiment of fertilization. With the technique of isothermal incubation, miscible displacement, cation exchange resin adsorbing, continuous extracting, the character of K fixing and releasing, the kinetics of K adsorbing and desorbing, the releasing of non-exchangeable k, the quantity- intensity relation of K, and the kinetics of K adsorbing and desorbing affected by the organic matter had been investigated and got the following results:1. The treatments with inorganic fertilizer had strong capacities in K fixation, while the treatments with organic fertilizer had strong capacities in K release. The difference in the amount of interlayer site fixed K maybe the main reason of the difference in the K fixation capacities between treatments with organic and inorganic fertilizer.The amount of fixed K was significantly correlated with the CEC/（exchangeable & non-exchangeable K）,and the amount of released K was significantly correlated with the CEC* exchangeable K/（exchangeable & non- exchangeable K）.2.The equilibrium times and capacities of K adsorption and desorption were different in each treatmen. Main effect factors were soil cation exchange capacity（CEC）、the contents of clay、organic matter and readily-available potassium.Elovich equation was the best model adopted to simulate K adsorption and desorption for all treatments, however some made the first order diffusion equation the best .Long time located fertilizations had casused changes between soil surface and characteristics of potassium3. The amount of non-exchangeable K released were highly correlated with their slowly-exchangeable K contents. The amount of non-exchangeable K released of the treatments with organic fertilizer were distinctly bigger than that of the treatments with inorganic fertilizer. The amounts of non-exchangeable K released from the treatments with K was much high, while that released from the treatment with N was relatively low.Release rates in the beginning stage （0-1h） were far beyond that in later stages. Release rates of the treatments with organic fertilizer in the beginning stage were higher than that of the treatments with inorganic fertilizer, and this maybe the main reason of the differences on the release rate and the amount of the non-exchangeable K between the treatments of organic and inorganic fertilizer. Parabolic equation was the best way to simulate the release of non-exchangeable K, which indicated the release of non-exchangeable K was diffusing controlled proceeding.4. Both of the treatments fertilized with organic fertilizer or with potassuim had much higher value of -ΔK⁰. There was a markedly or even more positive correlation between -ΔK⁰ with CEC, readily available K and clay contents.The ARe^K value was high in the treatments of organic fertilizer、potassuim and higher nitrition fertilizer（AN2、BN2）. The soil organic matter,CEC, readily available potassium,clay contents and saturation of K⁺ had a markedly positive correlation with ARe^K.The ARe^K value in the treatments with organic fertilizer is 1³ times higher than that of the treatment with inorganic fertilizer. The PBC^K value in the treatments with organic fertilizer were decreased with long-time fertilized of greenhouse vegetable soils. The PBC^K value in the treatments with potassuim and higher nitrition fertilizer（AN2、BN2） were low. The CEC, organic matter, readily available potassuim contents all had a markedly negative correlation with the PBC^K value. The value of edge sites exchangeable potassium devided by plan sites exchangeable potassium（e/p） had a markedly positive correlation with PBC^K, and was the main reason to affect the PBC^K value.The best equation to simulate the K release with H₂O and CaCl₂ extracting was both the first order equation, and that was power diffusing equation when extracted with NaCl, while that was two constants equation when extracted with NH₄Cl. Both in the treatments of with or without organic fertilizer , the treatments with only potassium（K）and the treatments with potassium and phosphorus （PK） both had higher quantities of potassium extraced by 0.1molL^-1NaCl, NH₄Cl,CaCl₂ and H₂O,but the treatments with only nitrition （N1）or the treatments with nitrition and phosphorus both had lower quantities of potassium extracted.5. About 30%-50% of the fixed K in the treatments with inorganic fertilizer could be extracted, while in the treatments with organic fertilizer, not only the newly fixed K could be extracted but also the elder fixed K. The rate of the amount of potassium released by countinous extracting to the amount of interlayer sites potassium was similar to that of readily available potassium /slowly available potassium in the soil,and had a markedly positive correlation between them. The release of fixed K when extracted with NaCl in each treatments were diffusing controlled proceeding6. The best equation to simulate the adsorbing and desorbing K after organic matter removed still was the Elovich equation. The simulations of equations to the treatments after organic matter removed were not as well as that of original treatments. Plan sites, edge sites and interlayer sites took part in the proceedings of adsorbing and desorbing simuitaneously. Which site was dominat in the proceeding would be the essence that impact the fitting degree of kinetic equations.The research had got a preliminary understanding that the capacities of K supplying in the different fertilized treatments in thegreenhouse vegetable soil had its own characteristics and were different in each. The differences in CEC, organic matter, clay （the role of Potassium sites）, readily and slowly available K contents （Potassium effective forms） were the main reason to affect the distinction of K supplying capacity in each treatment.更多还原