广西淡水养殖尾水水质监测及治理建议OA

In order to evaluate the discharge status and treatment efficiency of tail water from freshwater aquacul-ture in Guangxi,water samples were collected from effluent of tail water treatment facilities of eight high-density freshwater aquaculture enterprises in 2023.Using SC/T 9101-2007"Requirement for Water Discharge from Freshwater Aquaculture Pond"and GB 3838-2002"Environmental Quality Standards for Surface Water"as evaluation references,seven physicochemical indicators were determined,including total suspended solids(TSS),permanganate index(CODMn),total phosphorus(TP),total nitrogen(TN),pH,ammonia nitrogen(NH3-N),and dissolved oxygen(DO).The results indicated that compliance rates of TSS,CODMn,and pH in the treated water reached 100%,while nitrogen and phosphorus pollution,and low dissolved oxygen levels,re-mained notable issues.Specifically,the compliance rates of TN and TP with the secondary water quality standards(SC/T 9101-2007)were 83.93%and 98.21%,respectively.The compliance rates of NH3-N and DO with the Class Ⅲ surface water standards(GB 3838-2002)were 69.64%and 57.14%,respectively.These findings demonstrate that the overall quality of treated aquaculture tail water in Guangxi is still inadequate.Existing treat-ment processes exhibit obvious deficiencies in regulating nitrogen transformation and improving oxygenation effi-ciency.To enhance tail water treatment performance,it is recommended to prioritize the optimization of biological nitrogen removal modules and aeration system design.