Marine Assessment II -State and Trend of the Seas of Republic of Korea- (Summary)

Abstract

Trends in major physical and chemical characteristics of the seas: Medium to long-term trends for the past 10 years are illustrated for the major physical and biogeochemical parameters of the marine ecosystem. As for the coastal water quality, changes during 2012-2016 are shown compared to 2007-2011. Factors that show differences in trends among sea areas are shown by sea area and, for others, the trend for the entire sea area is represented. Trends in key indicators of marine food resources: In order to identify trends in marine food resources, seven indicators were set, including fisheries production, catch per unit effort (CPUE), fishery biomass, number of fishermen, aquaculture production, production per unit area (PPUA), and marine forest area. To see changes in trends, we compare the latest five-year indicator values of 2012-2016 with the indicator values of 2007-2011. The number of indicator values for comparing and analyzing the indicators is five for each period, which makes parametric tests impossible. Therefore, a Mann-Whitney non-parametric rank test was used. Changes in trends in human activities related to the marine environment: As for the human activities affecting the marine environment, the trends of vessel cargo amount, sewerage penetration rate, number of marine oil spill accidents, marine sand mining amount, marine litter amount, coastal erosion rate, marine tourism and leisure population, and marine science and technology research expense for the period of 2012-2016 are shown compared to the trends of 2007-2011. Status of marine biological diversity: The marine biodiversity and habitat have very limited data to enable assessment of their trends and health grade. Based on data from 2018, the distribution status of marine species, protected species, endangered marine species, endangered fish species, native marine species, marine mammals, seabirds, and marine reptiles are presented. For the habitat, we attempted to evaluate biodiversity or health grade in the rocky intertidal zone, soft intertidal zone, subtidal zone, deep sea basin, pelagic zone, and Dokdo offshore.However, information on species distribution in each habitat was quite fragmented and required constant monitoring.