The Method to Identity the Key Control Factor of Red Tide:A Case Study of Bohai Sea
LIN Guo-Hong;DONG Yue-Ru;LI Ke-Qiang;WANG Shu-ping;WANG Xiu-Lin;Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,College of Ocean University of China;State Key Laboratory of Analytical Chemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University;
Red tide has caused great economic loses because of the increasing occurrence frequency,geographic scope and the damage degree in the Bohai Sea.In this case,it is urgently to take measures to prevent and control the occurrence of red tide,the key of which is to determine the key control factors.However,there is no specific factors screening method in current study,or the screening methods are too single.Meanwhile,the key control factors of red tide may have differences in different sea areas.Therefore,based on red tide in the Bohai Sea,we establish an identification method of key control factors which includes the literature factor retrieval summary,alternative factor screening,alternative factor association analysis,the impact factor independence analysis,fluctuation analysis,and key control factor identification etc.Factors fluctuationis analyzed through entropy value method and variance coefficient method by analyzing statistical data associated with red tide occurrence from 1990 to 2009 in the Bohai Sea.And finally,the key control factors are identified with the theory of sensitivity analysis method by combing the principal component analysis and analytic hierarchyprocess(AHP).Results show that there are 14 factors with cumulative frequency reaching 90%,named alternative factors.Independences of 9 quantifiable factors are assured based on the framework of horizontal and vertical association.And then,weight of factors are calculated by both variance coefficient method and entropy method.Result shows that N/P,DIN,DIP,COD and rainfall reflect stronger information resolution ability.Based on the results of principal component analysis and analytic hierarchy process,the key control factors of red tide primarily are DIN,DIP and N/P in Bohai Sea,indicating that the frequent occurrence of red tide in the Bohai Sea may be connected with the nutrient inputs,especially the imbalance of nutrient structure caused by the excessive input of nitrogenous nutrients.Therefore,some measures such as increasing control of pollution,reducing input of terrestrial nutrients and mitigating degree of eutrophication can provide the basis for the prediction and the governance of red tide in the Bohai Sea.
【Fund】： 国家重点研发项目(2016YFC1402101);; 国家基金委-山东省联合基金项目(U1606404);; 国家减灾中心项目:“渤海典型赤潮灾害预防及减灾技术预研”资助~~
【CateGory Index】： X55
【CateGory Index】： X55