中国土壤与肥料
中國土壤與肥料
중국토양여비료
SOIL AND FERTILIZER SCIENCES IN CHINA
2015年
2期
22-28
,共7页
王帅%王楠%张晋京%范春莹
王帥%王楠%張晉京%範春瑩
왕수%왕남%장진경%범춘형
白浆土%吸附%NH4+%影响因素
白漿土%吸附%NH4+%影響因素
백장토%흡부%NH4+%영향인소
albic soil%adsorption%ammonium ion%influencing factor
为探究白浆土对氮素的吸附规律及其影响因素,有效指导白浆土氮肥的科学施用,本研究采用平衡吸附法,研究了温度、有机质含量、振荡时间和离子强度等因素对白浆土吸附NH4+的影响,结果表明:(1)随初始NH4+浓度(0~1000 mg/L)的增加,白浆土对其吸附量也增加,当NH4+浓度≥600 mg/L时,吸附渐趋饱和,温度升高(293~313 K)有利于该吸附反应的进行,表观热力学参数(ΔG<0、ΔH >0、ΔS >0)的变化表明, NH4+在白浆土表面的吸附是自发、吸热且混乱度增加的过程。(2)剖面层次所引起的有机质含量递减亦会对白浆土吸附NH4+的数量有所抑制。(3)振荡时间影响白浆土吸附NH4+的动力学过程,该过程可分为起始的快速反应阶段及经过360 min后的慢速反应阶段,所选用的4个动力学方程均能较好拟合这一动态过程。应用过渡态理论所计算的活化热力学参数(ΔG≠>0,ΔH≠>0,ΔS≠<0)表明, NH4+在白浆土上的动力学吸附过程是耗能且体系有序度增高的过程。(4)共存Na+在其不同浓度范围内对白浆土吸附NH4+的影响机制各有不同,当Na+≥0.4 mol/L时,提升其浓度有利于NH4+在白浆土上的吸附。综上所述,在较高土壤养分含量条件下,后移施用氮肥则更有利于其利用率的提升。
為探究白漿土對氮素的吸附規律及其影響因素,有效指導白漿土氮肥的科學施用,本研究採用平衡吸附法,研究瞭溫度、有機質含量、振盪時間和離子彊度等因素對白漿土吸附NH4+的影響,結果錶明:(1)隨初始NH4+濃度(0~1000 mg/L)的增加,白漿土對其吸附量也增加,噹NH4+濃度≥600 mg/L時,吸附漸趨飽和,溫度升高(293~313 K)有利于該吸附反應的進行,錶觀熱力學參數(ΔG<0、ΔH >0、ΔS >0)的變化錶明, NH4+在白漿土錶麵的吸附是自髮、吸熱且混亂度增加的過程。(2)剖麵層次所引起的有機質含量遞減亦會對白漿土吸附NH4+的數量有所抑製。(3)振盪時間影響白漿土吸附NH4+的動力學過程,該過程可分為起始的快速反應階段及經過360 min後的慢速反應階段,所選用的4箇動力學方程均能較好擬閤這一動態過程。應用過渡態理論所計算的活化熱力學參數(ΔG≠>0,ΔH≠>0,ΔS≠<0)錶明, NH4+在白漿土上的動力學吸附過程是耗能且體繫有序度增高的過程。(4)共存Na+在其不同濃度範圍內對白漿土吸附NH4+的影響機製各有不同,噹Na+≥0.4 mol/L時,提升其濃度有利于NH4+在白漿土上的吸附。綜上所述,在較高土壤養分含量條件下,後移施用氮肥則更有利于其利用率的提升。
위탐구백장토대담소적흡부규률급기영향인소,유효지도백장토담비적과학시용,본연구채용평형흡부법,연구료온도、유궤질함량、진탕시간화리자강도등인소대백장토흡부NH4+적영향,결과표명:(1)수초시NH4+농도(0~1000 mg/L)적증가,백장토대기흡부량야증가,당NH4+농도≥600 mg/L시,흡부점추포화,온도승고(293~313 K)유리우해흡부반응적진행,표관열역학삼수(ΔG<0、ΔH >0、ΔS >0)적변화표명, NH4+재백장토표면적흡부시자발、흡열차혼란도증가적과정。(2)부면층차소인기적유궤질함량체감역회대백장토흡부NH4+적수량유소억제。(3)진탕시간영향백장토흡부NH4+적동역학과정,해과정가분위기시적쾌속반응계단급경과360 min후적만속반응계단,소선용적4개동역학방정균능교호의합저일동태과정。응용과도태이론소계산적활화열역학삼수(ΔG≠>0,ΔH≠>0,ΔS≠<0)표명, NH4+재백장토상적동역학흡부과정시모능차체계유서도증고적과정。(4)공존Na+재기불동농도범위내대백장토흡부NH4+적영향궤제각유불동,당Na+≥0.4 mol/L시,제승기농도유리우NH4+재백장토상적흡부。종상소술,재교고토양양분함량조건하,후이시용담비칙경유리우기이용솔적제승。
To explore the rule and its influencing factors of nitrogen ( N) fertilizer adsorbtion on the albic soil for better in-struction of applying N fertilizer, equilibrium adsorption method was performed to study the effects of temperature, content of organic matter, oscillation time and ionic strength on the adsorption of NH4+ on the albic soil. The results shown that (1) with the initial concentrations of NH4+ increasing (0~1 000 mg/L), its adsorption capacity on the albic soil was also enhanced. When the initial NH4 +concentration exceeded 600 mg/L, the adsorption capacity gradually reached the saturated state. The increase of reaction temperature (293~313K) was helpful for the absorption. The changes of apparent thermodynamic param-eters (ΔG<0, ΔH>0, ΔS>0) indicated that the NH4+ adsorption process was spontaneous, endothermic and increased in degree of disorder; (2) The gradual decline of organic matter content with soil depth could lower the NH4+ adsorption capacity;(3) The sorption kinetics was affected by determinable oscillation time, which could be divided into the initial fast phase and the subsequent slow phase after 360 min. This dynamic process was fitted well by all the four selected equations; From the thermodynamic parameters of activation (ΔG≠ >0, ΔH≠ >0, ΔS≠ <0) calculated by the transition state theory, it was shown that the adsorption of NH4+ onto the albic soil was energy-consumed with increasing of the degree of order; (4) The dif-ferent concentrations of coexisting Na+ in a certain range had different influencing mechanisms on the adsorption of NH4+. When the concentration of Na+ exceeded 0. 4 mol/L, the adsorption would be enhanced. In all, the backward-shift N fertilizer application in the albic soil with high fertility could be helpful to enhance its utilization efficiency.