[A-HW24] Material transportation and cycling at the land-sea interface: from headwaters to the ocean

[AHW24-07] Research for setting local environmental thresholds that contribute to coral reef conservation in the era of high CO₂

★Invited Papers

*Akira Iguchi^1,7, Atsushi Suzuki^1,7, Mariko Iijima¹, Jun Yasumoto², Takashi Nakamura³, Kazuhiko Sakai⁴, Ko Yasumoto⁵, Nanami Mizusawa⁵, Naoki H. Kumagai⁶ (1.Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 2.Faculty of Agriculture, University of the Ryukyus,, 3.Faculty of Science, University of the Ryukyus, 4.Tropical Biosphere Research Center, University of the Ryukyus, 5.School of Marine Biosciences, Kitasato University, 6.Center for Climate Change Adaptation, National Institute for Environmental Studies, 7.Research Laboratory on Environmentally-conscious Developments and Technologies [E-code])

Keywords:Coral reefs, Nutrients, Coral calcification, Metagenome

We are currently conducting research in the coral reef areas of the Ryukyu Archipelago with the aim of determining the thresholds of environmental factors that ensure healthy coral growth, based on an understanding of the water cycle and nutrient loads unique to the islands and experiments to evaluate the effects of combined stresses on corals that take into account terrestrial-derived loads (e.g., nutrients). In this presentation, we will outline the details of the nutrient load in coral reefs that we have identified so far, focusing on accumulated nutrients (phosphate bound to calcareous sediments), the evaluation of the effects of accumulated nutrients on coral calcification, and the bacterial load based on metagenomic analysis, and describe the direction of our future research.