日本地球惑星科学連合2018年大会

講演情報

[JJ] Eveningポスター発表

セッション記号 H (地球人間圏科学) » H-CG 地球人間圏科学複合領域・一般

[H-CG28] 海岸低湿地における地形・生物・人為プロセス

2018年5月20日(日) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:藤本 潔(南山大学)

[HCG28-P04] 三浦半島江奈湾干潟の堆積物中のCNS元素分析

*山本 有夏1北村 晃寿1山田 和芳2 (1.静岡大学、2.ふじのくに環境史ミュージアム)

キーワード:CNS元素分析、干潟の堆積物

The ratio of total sulfur (TS) to total organic carbon (TOC) (C/S ratio) and concentration of TS have been used to identify whether sediment deposited under freshwater or brackish water or sea water. For example, Berner & Raiswell (1984) reported that the C/S ratio of marine sediment is 0.5-5 (the average is 2.8±1.5), and freshwater sediment is >10, for sediment containing >1% TOC. Terashima et al. (1983) analyzed sediments of freshwater lakes, brackish water lakes and deep sea at and around Japan. The results showed that C/S ratio of marine sediments and freshwater sediments are >6 and >9, respectively. They also suggested that TS in freshwater sediments is usually low, but that the ratio of Lake Suwa (0.09 %) is similar to those of deposits of Obama (0.07 %) and Suruga (0.09 %) bays. More recently, Sheng et al. (2015) investigated Laizhou Bay in China, where the mean C/S ratios were 55.91 in marine sediment and 35.08 in river sediment, respectively. TS in marine sediment were 0.01-0.09 % and the average is 0.03 %. TS in river sediment were 0.42 %, and were anthropogenically-derived. Since C/S ratio and TS vary considerably from region, it is necessary to construct a determination indicator for the research area. This study reports CNS elemental analysis of tidal flat sediments in Ena Bay , Miura Peninsula, Kanagawa Prefecture, central Japan to establish the criteria for applying Holocene alluvial lowland around Shizuoka Prefecture.