日本地球惑星科学連合2021年大会

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[E] ポスター発表

セッション記号 A (大気水圏科学) » A-HW 水文・陸水・地下水学・水環境

[A-HW22] 流域生態系における物質輸送と循環:源流から沿岸まで

2021年6月4日(金) 17:15 〜 18:30 Ch.09

コンビーナ:前田 守弘(岡山大学)、入野 智久(北海道大学 大学院地球環境科学研究院)、小野寺 真一(広島大学大学院先進理工系科学研究科)、Adina Paytan(University of California Santa Cruz)

17:15 〜 18:30

[AHW22-P22] The effects of groundwater runoff on the coastal bacterial communities near the Ryukyu Limestone area

*水澤 奈々美1、井口 亮2、飯島 真理子2、丸山 莉緒1、安元 純3、安元 剛1、広瀬 美奈4、渡部 終五1 (1.北里大学海洋生命科学部、2.産業技術総合研究所、3.琉球大学農学部、4.トロピカルテクノプラス)

Corals are exposed to various stressors such as high water temperature and anthropogenic activities. For example, those inhabiting the coastal area are thought to be strongly affected by terrestrial runoff rich in nutrients and other anthropogenic contaminants. Groundwater is believed to act as a carrier for terrestrial materials running into coastal waters in the southern part of Okinawa Jima Island. However, its lineage to the damage of corals has not been well understood. Because the microbial community plays key roles in biogeochemical cycles, we performed as a first step metagenomic analysis on the coastal seawater as well as on the groundwater in the southern part of Okinawa Jima Island to evaluate the effect of the groundwater runoff on the coastal ecosystem including coral reefs. Coastal water and groundwater samples were collected from Yaese Town and filtered through 0.2 µm pore size filters. Amplicon libraries were constructed using Pro341F/Pro805R primers targeting the V3-V4 region of the bacterial 16S rRNA gene and analyzed by an Illumina MiSeq system, then obtained fastq files were processed by QIIME2. As a result, four prokaryotic phyla, Proteobacteria, Bacteroidetes, Cyanobacteria and Actinobacteria, were found to be dominant in both the coastal water and groundwater samples. Cluster analysis revealed that the samples were divided into 2 groups; one included 16 samples from the coastal waters, and another included 8 samples from the coastal water and 7 samples from the groundwater. Clustering of the latter group comprised of both the coastal water and groundwater samples suggest that the groundwater from certain areas in this study affects the coastal ecosystem at the bacterial community level. We are currently surveying environmental factors in the groundwater which may affect the coastal bacterial communities.