环境因子对海州湾表层沉积物中氨氮吸附-解吸的影响  

Effects of Environmental Factors on Ammonia Nitrogen Adsorption and Desorption in the Surface Sediments of Haizhou Bay

作　　者：王功芹[1] 张硕[2,3,4] 李大鹏[2] 张中发[2] 李莉[2] WANG Gongqin;ZHANG Shuo;LI Dapeng;ZHANG Zhongfa;LI Li(School of Environment, Beijing Normal University, Beijing 100875, China;College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China;Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China;National Engineering Research Center for Oceanic Fisheries, Shanghai 201306, China)

机构地区：[1]北京师范大学环境学院,北京100875 [2]上海海洋大学海洋科学学院,上海201306 [3]大洋渔业资源可持续开发省部共建教育部重点实验室,上海201306 [4]国家远洋渔业工程技术研究中心,上海201306

出　　处：《生态环境学报》2017年第1期95-103,共9页Ecology and Environmental Sciences

基　　金：农业部转产转业项目-江苏省海州湾海洋牧场示范项目(D-8006-13-8023;D8006-12-8018);国家公益性行业(农业)科研专项(201003068)

摘　　要：沉积物中的有机质在微生物作用下矿化,产生大量氨氮,大部分氨氮会被沉积物颗粒吸附,影响氮在沉积物中的硝化、反硝化以及厌氧氨氧化等作用,因此,沉积物对氨氮的吸附-解吸作用是影响沉积物中氮循环的一个重要过程。海湾具有水动力作用强烈,扰动和盐度等物理化学条件复杂多变的特点,研究环境条件变化对沉积物中氨氮吸附-解吸的影响有助于揭示其对沉积物-水界面氮营养盐交换的影响机制。因此,以海州湾表层沉积物样品进行室内模拟实验,通过吸附-解吸动力学和热力学实验,研究扰动大小、粒度分布和盐度等环境因子对氨氮吸附-解吸的影响。结果表明,吸附和解吸是一个复合动力学过程,主要在30 min内完成,30 min以后逐渐达到动力学平衡状态;准二级吸附动力学方程和修正的Elovich模型对沉积物吸附氨氮的模拟效果较好,一级反应动力学方程可以较好地描述沉积物对氨氮的解吸动力学过程。热力学模型的拟合结果显示沉积物对氨氮的吸附符合Henry模型,描述解吸过程的最优模型是Langmuir模型。一定范围内振荡频率的增加、粒径的减小、盐度的降低都会提高沉积物对氨氮的吸附能力;一定范围内振荡频率的增加、粒度的增大、盐度的升高都会增强沉积物对氨氮的解吸量。该研究可为进一步认识和理解环境因子变化对氨氮吸附-解吸的影响及机制提供理论依据。The mineralization of organism in the sediment could generate large amounts of ammonia nitrogen.Most of the ammonianitrogen will be adsorbed by the sediments particles and will affect the nitrification,denitrification and anammox of nitrogen in thesediments,so the adsorption-desorption of ammonia nitrogen in sediments is an important process in nitrogen cycle.Bay hascomplicated and changing characteristics in physical and chemical conditions,such as hydrodynamic force function,disturbance andsalinity.Studies on the effects of environmental factors on ammonia nitrogen adsorption and desorption could reveal the influencingmechanism of nitrogen exchange in sediment-water surface.Therefore,the regulatory effects of disturbance intensity,sizedistribution and salinity on ammonia nitrogen adsorption and desorption in surface sediments were investigated through modeling inlaboratory along the Haizhou Bay,using adsorption and desorption dynamic and thermodynamics experiment.The results showedthat the adsorption and desorption is a complex dynamic process.The dynamic process mainly finishes in30minutes and reachequilibrium state after30minutes.The quasi-dynamic equations and the modified Elovich model can have a good description of theadsorption process.The first-order kinetics equation could fit desorption dynamics process.The fitting results of thermodynamicmodel revealed that the adsorption of ammonia nitrogen in the sediments conform to the Henry model and the optimal model todescribe desorption is Langmuir model.The study also showed that the adsorption capacity of surface sediment increased withdisturbing condition in a specific range,particle diameter reducing and salinity decreasing in a specific range.The desorptioncapacity of surface sediment increased with disturbing frequency,particle diameter and salinity increasing.This research will providethe theory basis for further recognize and understand the effect and its mechanism of environmental factors changes on adsorptionand desorption of ammonia nitrogen.

关 键 词：海州湾 表层沉积物 扰动 粒度分布 盐度 氨氮 吸附-解吸 

分 类 号：X834[环境科学与工程—环境工程]