Measurement and Spatio-temporal Evolution of Equal-standard Pollution Loading of Mariculture in Zhejiang Province

In order to explore the pollution status of main mariculture areas in Zhejiang Province, this paper made a preliminary assessment of the pollution generated by mariculture activities in Zhejiang Province, by using the data of the fishery Statistics of Zhejiang Province from 2005 to 2021 and Manual for the First National Survey of Pollution Sources Production and Discharge Coefficient of Aquaculture Pollution Sources. And different kinds of pollutants were converted to equal-standard pollution loading. Meanwhile, an analysis of spatio-temporal evolution of equal-standard pollution loading and mariculture yield of major coastal cities in Zhejiang Province was conducted. The results showed that, the cumulative equal-standard pollution loading of mariculture in Zhejiang Province from 2005 to 2021 exceeded 700 000×104 m3/a, and revealed a trend of wavelike rise first and continuously rise after. Equal-standard pollution loading the highest is the highest in Ningbo with the cumulative volume of 271 769.2×104 m3/a. followed by Taizhou, Zhoushan and Wenzhou. From the perspective of mariculture species, shellfish produced the highest equal-standard pollution loading. And from the perspective of mariculture mode, raft cultivation and bottom sowing produce the highest equal-standard pollution loading. Spatio-temporal evolution analysis showed that, the changes of pollution and mariculture yield in Zhejiang were basically synchronized, and the equal-standard pollution loading and mariculture yield showed obvious growth trend