Monitoring ocean-atmosphere interactions: dissolved organic matter (DOM), bacteria, and antibiotic-resistant genes (ARGs) in the Pacific and Southern Oceans

• Main Author: Jang, Jiyi
• Other Authors: Cho, Kyung Hwa
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Ulsan National Institute of Science and Technology 2022
• Subjects: Pacific; Ross Sea; Southern Ocean; Sea ice
• Online Access: https://scholarworks.unist.ac.kr/handle/201301/57425; http://unist.dcollection.net/common/orgView/200000603015

Department of Urban and Environmental Engineering (Environmental Science and Engineering) Seawater covers more than 70 percent of surface of the Earth and contains dissolved organic matters (DOM) and microorganisms. Sea is one of the important sources of organic and genetic matters of the atmosphere, which can consequently affect climate change and global warming. Accordingly, big data on the haracteristics and origins of organic and genetic matters in seawaters and atmosphere allows us to understand the changes in ecosystem and climate in the long term. Moreover, the application of deep learning technique is expected o be promising in predicting the occurrence of pollutants in the environment including seawaters. Therefore, in this study, I aimed 1) to analyze big data on the characteristics and origins of organic matter in seawaters, 2) to investigate big data on the characteristics and origins of genetic matter in seawaters, and 3) to develop deep learning techniques and predict the occurrence of the genetic matters in seawaters. First, to identify latitudinal characteristics of DOM in seawater, seawaters were collected along a transect from the western Pacific Ocean (36??N) to the Southern Ocean (74??S). Based on optical properties of DOM in seawaters, it seems that DOM were affected by terrestrial sources in the mid-latitude, while microbiologically produced in the low-latitude and produced within the ocean in the high-latitude. DOM characterization at molecular-level by Orbitrap-MS showed similar result to optical properties despite dominant lignin-like component in overall stations. In addition, the DOM characteristics in aerosol were analyzed with Orbitrap-MS, indicating that lignin-like component affects dominantly from the ocean to the atmosphere probably due to hydrophobicity of lignin. On the other hand, lipid-like component was dominant in aerosol collected from Ross Sea (RS) in the Southern Ocean where sea ice exists. These DOM characteristics in aerosol of RS were related to those of sea ice, ...