Carbon sink potential of eutrophic lake sediments: a reconstruction of the potntial in lakes Nakaumi and Shinji during the last about four hundred years

富营养化湖泊沉积物的碳汇潜力：近四百年来中海湖和真道湖碳汇潜力的重建

• 批准号: 22540470
• 负责人: SAMPEI Yoshikazu
• 金额: $ 3.16万
• 依托单位: Shimane University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2010
• 资助国家: 日本
• 起止时间: 2010 至 2012
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-22540470/
• 关键词: 汽水域; 有機物濃度; 有機炭素埋積速度; 二酸化炭素; 硫化水素; カーボンシンク; 中海; 宍道湖; 富栄養湖; 中海・宍道湖; サプロペル

Carbon sink potential of eutrophic lake sediments from lakes Nakaumi and Shinji was studied for recent and several hundred years environments using surface sediments and sediment cores.TOC (total organic carbon) contents of southern and central L. Nakaumi showed high sapropelic about 3.6~4.0% in the 1cm surface sediments. These values are constant from AD1997. TOC contents of all samples from L. Shinji showed also sapropelic and high about 3.5~4.3% except for eastern part. These TOC values in L. Shinji are not changed during the last 5 years. According to the result of C/N ratio (7-9) and py-GC-MS, origin of organic matter in both lakes is supposed to be predominant phyto-plankton. Sediment cores showed low TOC contents about 1% between AD1800 and 1900 in both L. Nakaumi and Shinji and TOC contents drastically increased from 1% to 4% after AD1900. Analysis of AD2003 data by our preliminary research indicates that TOC contents over 3.5% of surface sediments have a good positive correlat … More ion with H2S (ppm), showing an equation: H2S (ppm) = 13.9 * TOC (%) - 52.1 (TOC>3.5%). Atmospheric CO2 concentration on the northeastern Nakaumi was low about 360 ppm in average (April to May, 2013), which could depend on spring blooming of phyto-plankton. Impressive difference of the CO2 concentration between daytime and nighttime was up to 80 ppm. Average OCARs in the surface sediments of L. Nakaumi and Shinji are 7.0 mgC/cm2/y and 4.0 mgC/cm2/y，respectively based on the sedimentation rate reported by Kanai et al., (1998, 2002). As a result, L. Nakaumi and Shinji have a potential carbon sink of about 6,000 tonC/y and 3,200 tonC/y, respectively. Low OCARs of the cored sediments with low TOC about 1% in L. Nakaumi during 50-25 cm (1770-1890) and TOC about 0.7% in L. Shinji during 30-20cm (1830-1890), i.e. Little Ice Age, suggested 2,000 tonC/y and 1,300 tonC/y, respectively. These low values during cool climate are about one - third of the present potential. These brackish lakes are characterized as a quick response carbon sink for climate change. Less

利用表层沉积物和沉积物岩心研究了近几百年来Nakaumi湖和Shinji湖富营养化湖泊沉积物的碳汇潜力。Nakaumi湖南部和中部的TOC(总有机碳)在1 cm表层沉积物中表现出较高的腐泥质含量，约为3.6~4.0%。这些值从1997年起是恒定的。除东部外，所有样品的总有机碳含量也表现为腐殖质，含量较高，为3.5~4.3%。这些TOC值在过去的5年中没有变化。根据C/N比(7~9)和Py-GC-MS分析结果，推测两湖有机质来源均以浮游植物为主。Nakaumi和Shji的沉积物岩心在AD1800至1900年间TOC含量都很低，约为1%，而在AD1900年后，TOC含量从1%急剧上升到4%。通过前期研究对2003年数据的分析表明，3.5%以上的表层沉积物中总有机碳含量与…有很好的正相关关系H_2S(Ppm)=13.9×TOC(%)-52.1(TOC&GT；3.5%)。Nakaumi东北部的大气CO2浓度较低，平均为360ppm(2013年4月至5月)，这可能取决于春季浮游植物的大量繁殖。令人印象深刻的是，白天和晚上的二氧化碳浓度差异高达80ppm。根据Kanai等人(1998,2002)报告的沉积速率，Nakaumi和Shjii表层沉积物中的平均OCARs分别为7.0mgC/cm2/y和4.0mgC/cm2/y。因此，L.Nakaumi和Shjii的潜在碳汇分别约为6000 tonC/y和3200 tonC/y。50-25 cm(1770-1890)Nakaumi和30-20 cm(1830-1890)新集低TOC约0.7%的岩心沉积物的低OCAR分别为2000tonC/a和1300tonC/a。在气候凉爽的时候，这些低值大约是目前潜力的三分之一。这些咸水湖泊的特点是对气候变化的快速反应碳汇。较少

项目成果

中海における底質表層の全有機炭素濃度の変化

中海底部沉积物表层总有机碳浓度变化

• 发表时间: 2012
• 作者: Amm;O.;R. Fujii;K. Kauristie;A. Aikio;A. Yoshikawa;A. Ieda;and H. Vanhamaki;富樫 均・原山 智・北野 聡;植田勇人・臼杵直・平内健一・三浦亮・YK10-13Leg2乗船研究者一同;三瓶良和
• 通讯作者: 三瓶良和