氧化还原电位及微生物对水库底泥释磷的影响  

Effects of oxidation-reduction potential and microorganism on the release of phosphorus from sediments

作　　者：黄廷林[1,2] 周瑞媛 夏超[1,2] 徐金兰[1,2] 

机构地区：[1]西部建筑科技国家重点实验室培育基地,西安710055 [2]西安建筑科技大学环境与市政工程学院,西安710055

出　　处：《环境化学》2014年第6期930-936,共7页Environmental Chemistry

基　　金：国家科技支撑计划(2012BAC04B02);国家自然科学基金重点项目(50830303)资助

摘　　要：为了解上覆水环境以及生物作用对水库底泥释磷作用的影响,本研究通过选取石砭峪水库底泥作为贫营养水库底泥代表,在实验室模拟了不同物理化学条件及不同微生物条件下水库底泥静态释磷过程.实验期间调查了上覆水处溶解氧(DO)、氧化还原电位(ORP)、pH等条件的影响,定期监测了上覆水中的溶解性正磷酸盐(PO3-4)、总磷(TP)、亚铁离子(Fe2+),反应开始前与结束后测定了底泥中不同持留形态的磷组分,其中包括铁铝结合态磷(Fe/Al-P)、钙磷(Ca-P)、无机磷(IP)、有机磷(OP)、总磷(TP),同时测定了反应前后底泥中碱性磷酸酶活性(APA).实验证明,ORP<0 mV的强还原性条件能够促进底泥中的磷大量释放,同时伴随着大量的Fe2+进入上覆水中.底泥中释放的磷是以Fe/Al-P和IP为主,并且进入水体中的磷大部分是PO3-4,占超过水体中TP的50%以上.底泥中微生物的活动能够促进OP的分解和转化,对底泥中其他形态的磷转化为PO3-4进入水体影响不大.同时微生物也可以吸收上覆水中除PO3-4之外的磷营养进入底泥中储存起来.In order to understand the effects of overlying water environment and the microbial activity on the release of phosphorus（ P） from sediments,static release processes of P in sediments of reservoir under different physical and chemical conditions and microbial activity conditions were simulated in the laboratory by selecting sediments in Shibianyu Reservior as representative of the poor nutrient reservoir. Dissolved oxygen（ DO）,oxidation-reduction potential（ ORP） and pH value in overlying water were measured during the experiment. Soluble orthophosphate（ PO3-4）,total phosphorus（ TP） and ferrous ions（ Fe2＋） were regularly monitored by on-line monitoring. P of different forms including Fe-bound phosphorus（ Fe /Al-P）,Ca-P,inorganic phosphorus（ IP）,organ phosphorus（ OP） and total phosphorus（ TP） and alkaline phosphatase（ APA） in sediments were measured before and after the reaction. The experiment showed that strong reducing conditions with ORP less than 0 mV promoted massive release of P from the sediments,accompanied by a large number of Fe2＋ entering into overlying water. P released from sediments was mainly IP and Fe /Al-P,and that entered into water was mainly PO3-4,accounting for more than 50% of the TP in the water.Microbial activity in sediments promoted the decomposition and transformation of OP,which had little effect on the transformation of P from other forms to PO3-4. Microbes in the sediments also absorbed P except PO3-4in overlying water.

关 键 词：底泥 释放 磷 ORP 微生物 

分 类 号：X524[环境科学与工程—环境工程] X172