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Late Quaternary Strata and Carbon Burial Records in the Yellow River Delta, China 被引量:4
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作者 ZHAO Guangming YE Siyuan +2 位作者 LI Guangxue DING Xigui YUAN Hongming 《Journal of Ocean University of China》 SCIE CAS 2015年第3期446-456,共11页
Sediment carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. To clarify the late Quaternary strata and carbon burial records in YeUow Riv... Sediment carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. To clarify the late Quaternary strata and carbon burial records in YeUow River delta (YRD), detailed analysis of benthic foraminifera, total carbon (TC), organic carbon (Corg), sedimentary characteristics and moisture contents of sediments, was performed on core ZK3, 30.3 m in length and obtained from YRD in 2007. Eight depositional units (designated U1-U8 in ascending order) were identified. A comprehensive analysis method of historical geography and sedimentary geology was used to de- termine the precise depositional ages of the modem Yellow River delta (MYRD), from which pre-MYRD ages were deduced. The results indicates that the maximum burial rates of TC, inorganic carbon (IC) and Corg occurred in the delta front (U5), and the mini- mum in the shallow sea (U3). Remarkable high sedimentation rates in the MYRD are responsible for burial efficiency of carbon, with an average rate of Corg burial reaching 2087±251 g(m2yr)-1, and that of IC reaching 13741±808g(m2yr)-1, which are much higher than those of other regions with high contents of Corg. Therefore, YRD has a significant burial efficiency for carbon sequestration. 展开更多
关键词 Yellow River delta late Quaternary strata carbon burial rate organic carbon inorganic carbon
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Impact of mangrove vegetation on seasonal carbon burial and other sediment characteristics in the Vellar-Coleroon estuary, India 被引量:1
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作者 Kandasamy Kathiresan Venugopal Gomathi +1 位作者 Raj Anburaj Kandasamy Saravanakumar 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第4期787-794,共8页
This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in... This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in the Vellar-Coleroon estuarine complex, India. The sedi- ment characteristics varied significantly between mangrove-vegetated and non-vegetated habitats or seasons of analysis, but not between soil depths. The mangrove sediments were rich in total carbon and total or- ganic carbon as compared to non-mangrove sediments (p 〈0.01). Total carbon was 98.2% higher in mature mangroves and 41.8% in planted mangroves than that in non-mangrove soil. Total organic carbon was as much as 2.5 times greater in mature mangroves and 2 times greater in planted mangroves than that in unvegetated soil. Carbon contents also varied many fold by season. Total carbon content was 8.6 times greater during pre-monsoon, 4.1 times greater during post-monsoon and 2.5 times greater during monsoon than during summer (P〈0.01 in all cases). Similarly, total organic carbon was 5.9 times greater during pre-monsoon, 3.1 times greater during post-monsoon and 69% greater during monsoon than during summer. In general, higher levels of sediment carbon were recorded during pre and post-monsoon seasons than during other seasons. Total carbon concentration was correlated negatively to temperature, sand and phosphorus (P 〈0.01); positively correlated with redox potential, silt, clay, C/N ratio, potassium (P 〈0.01) and nitrogen (P〈0.05); but not correlated with soil depth, pH or salinity. This work revealed that the carbon burial was rapid at the annual rate of 2.8% for total carbon, and 6.7% for total organic carbon in mangrove-planted sediment. Cleating of mangroves can result in significantly and rapidly reduced carbon stores.Our study highlights the importance of natural and plantation mangrove stands for conserving sediment carbon in the tropical coastal domain. 展开更多
关键词 mangrove sediment carbon burial total carbon total organiccarbon
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Carbon Burial in Young Tropical Reservoirs Is Higher at Lower Latitudes*
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作者 Elizabeth Sikar Marco Aurelio dos Santos +9 位作者 Ana Carolina Moterani Isabella Matvienko Ana Carla Martins Veras Juliana Pinto Pereira Dias Orleno Marques da Silva Junior Claudio Pavani Marcelo Amorim Teodosio das Neves Milisse Nzualo Ayr Manoel Portilho Bentes Junior Rogerio Duarte 《Journal of Geoscience and Environment Protection》 2021年第12期84-99,共16页
Man-made environments such as tropical hydroelectric reservoirs alter the preexisting carbon (C) cycle and remove C from circulation through burial in sediments. Carbon burial (CB) was measured using the silica-tracer... Man-made environments such as tropical hydroelectric reservoirs alter the preexisting carbon (C) cycle and remove C from circulation through burial in sediments. Carbon burial (CB) was measured using the silica-tracer method during four field surveys in the less than six-year-old Belo Monte tropical reservoir. Fresh C sedimentation was also measured. Belo Monte’s CB median rate 276 (n = 84;min 0;max 352,625 mg C&#183;m<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>2</sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>d<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>1</sup>) is within the range (230 to 436 mg C<span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>m<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>2</sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>d<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>1</sup>) of CB rates measured further downstream at the Xingu Ria and higher than the averaged over 50 years oceanic rate 244 mg C<span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>m<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>2</sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>d<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>1</sup> estimated for an increasingly deoxygenated ocean. Carbon burial median rates of tropical reservoirs with similar age and trophic state correlate inversely with latitude at a rate of 17.5 mg C<span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>m<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>2</sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#F7F7F7;">&#183;</span>d<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45;</span>1</sup> per degree. Carbon burial efficiency of these reservoirs correlates positively with latitude at a ratio of 0.22% per degree. 展开更多
关键词 carbon burial SEDIMENTS Hydroelectric Reservoirs
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Potential evaluation of saline aquifers for the geological storage of carbon dioxide: A case study of saline aquifers in the Qian-5 member in northeastern Ordos Basin
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作者 Yan Li Peng Li +4 位作者 Hong-jun Qu Gui-wen Wang Xiao-han Sun Chang Ma Tian-xing Yao 《China Geology》 CAS CSCD 2024年第1期12-25,共14页
The well-developed coal electricity generation and coal chemical industries have led to huge carbon dioxide(CO_(2))emissions in the northeastern Ordos Basin.The geological storage of CO_(2) in saline aquifers is an ef... The well-developed coal electricity generation and coal chemical industries have led to huge carbon dioxide(CO_(2))emissions in the northeastern Ordos Basin.The geological storage of CO_(2) in saline aquifers is an effective backup way to achieve carbon neutrality.In this case,the potential of saline aquifers for CO_(2) storage serves as a critical basis for subsequent geological storage project.This study calculated the technical control capacities of CO_(2) of the saline aquifers in the fifth member of the Shiqianfeng Formation(the Qian-5 member)based on the statistical analysis of the logging and the drilling and core data from more than 200 wells in the northeastern Ordos Basin,as well as the sedimentary facies,formation lithology,and saline aquifer development patterns of the Qian-5 member.The results show that(1)the reservoirs of saline aquifers in the Qian-5 member,which comprise distributary channel sand bodies of deltaic plains,feature low porosities and permeabilities;(2)The study area hosts three NNE-directed saline aquifer zones,where saline aquifers generally have a single-layer thickness of 3‒8 m and a cumulative thickness of 8‒24 m;(3)The saline aquifers of the Qian-5 member have a total technical control capacity of CO_(2) of 119.25×10^(6) t.With the largest scale and the highest technical control capacity(accounting for 61%of the total technical control capacity),the Jinjie-Yulin saline aquifer zone is an important prospect area for the geological storage of CO_(2) in the saline aquifers of the Qian-5 member in the study area. 展开更多
关键词 carbon burial carbon neutral CO_(2) storage in saline aquifer Distributary channel sand body Potential evaluation Technical control capacity CO_(2)geological storage engineering Ordos Basin
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Burial fluxes and source apportionment of carbon in culture areas of Sanggou Bay over the past 200 years 被引量:2
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作者 LIU Sai HUANG Jiansheng +3 位作者 YANG Qian YANG Shu YANG Guipeng SUN Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期23-30,共8页
In this study, we assessed the burial fluxes and source appointment of different forms of carbon in core sediments collected from culture areas in the Sanggou Bay, and preliminarily analyzed the reasons for the greate... In this study, we assessed the burial fluxes and source appointment of different forms of carbon in core sediments collected from culture areas in the Sanggou Bay, and preliminarily analyzed the reasons for the greater proportion of inorganic carbon burial fluxes (BFTIc). The average content of total carbon (TC) in the Sanggou Bay was 2.14%. Total organic carbon (TOC) accounted for a small proportion in TC, more than 65% of which derived from terrigenous organic carbon (Ct), and while the proportion of marine-derived organic carbon (Ca) increased significantly since the beginning of large-scale aquaculture. Total inorganic carbon (TIC) accounted for 60%-75% of TC, an average of which was 60%, with a maximum up to 90% during flourishing periods (1880-1948) of small natural shellfish derived from seashells inorganic carbon (SheU-IC). The TC burial fluxes ranged from 31 g/(m2.a) to 895 g/(m2.a) with an average of 227 g/(m2.a), which was dominated by TIC (about 70%). Shell-IC was the main source of TIC and even TC. As the main food of natural shellfish, biogenic silica (BSi) negatively correlated with BFTIc through affecting shellfish breeding. BFTIc of Sta. S1, influenced greatly by the Yellow Sea Coastal Current, had a certain response to Pacific Decadal Oscillation (PDO) in some specific periods. 展开更多
关键词 carbon sources carbon burial fluxes shells inorganic carbon (Shell-IC) marine-derived organic carbon (Ca) Sanggou Bay
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Organic carbon source and burial during the past one hundred years in Jiaozhou Bay,North China 被引量:15
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作者 LI Xuegang YUAN Huamao LI Ning SONG Jinming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第5期551-557,共7页
Organic carbon (OC), total nitrogen (TN), and ^210Pb in core sediment were measured to quantify the burial of organic carbon and the relative importance of allochthonous and autochthonous contributions during the ... Organic carbon (OC), total nitrogen (TN), and ^210Pb in core sediment were measured to quantify the burial of organic carbon and the relative importance of allochthonous and autochthonous contributions during the past one hundred years in Jiaozhou Bay, North China. The core sediment was dated using ^210Pb chronology, which is the most promising method for estimation of sedimentation rate on a time scale of 100-150 years. The variation of the burial flux of organic carbon in the past one hundred years can be divided into the following three stages: (1) relatively steady before 1980s; (2) increasing rapidly from the 1980s to a peak in the 1990s, and (3) decreasing from the 1990s to the present. The change is consistent with the amount of solid waste and sewage emptied into the bay. The OC:TN ratio was used to evaluate the source of organic carbon in the Jiaozhou Bay sediment. In the inner bay and bay mouth, the organic carbon was the main contributor from terrestrial sources, whereas only about half of organic carbon was contributed from terrestrial source in the outer bay. In the inner bay, the terrestrial source of organic carbon showed a steady change with an increase in the range of 69%-77% before 1990 to 93% in 2000, and then decreased from 2000 because of the decrease in the terrestrial input. In the bay mouth, the percentage of organic carbon from land reached the highest value with 94% in 1994. In the outer bay, the sediment source maintained steady for the past one hundred years. 展开更多
关键词 organic carbon source burial Jiaozhou Bay
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Burial fluxes and sources of organic carbon in sediments of the central Yellow Sea mud area over the past 200 years 被引量:4
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作者 YANG Shu YANG Qian +3 位作者 LIU Sai CAI Deling QU Keming SUN Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期13-22,共10页
Long-term changes of composition, sources and burial fluxes of TOC (total organic carbon) in sediments of the central Yellow Sea mud area and their possible affecting factors are discussed in this paper. Firstly, si... Long-term changes of composition, sources and burial fluxes of TOC (total organic carbon) in sediments of the central Yellow Sea mud area and their possible affecting factors are discussed in this paper. Firstly, similarity analysis is employed to confirm that the carbon burial features resulted from two collected cores are typical in the central Yellow Sea mud area where YSWC (Yellow Sea Warm Current) is prevalent. On this basis, the burial flux of TOC here was considered to be 235.5-488.4 pmol/(cm^2.a) since the first industrial revolution, accounting for about 70%-90% among burial fluxes of TC (total carbon) in the sediments. Compared TOC/TC ratio in the two cores with that in other marine sediments worldwide, we suggest that the growth of calcareous/non-calcareous organisms and dissolution of IC (inorganic carbon) are important factors controlling the TOC/TC ratio in sediment. Results of two-end mixed model based on fi13C data indicate that marine-derived organic carbon (OCa) is the main part among total burial organic carbon which accounts for a ratio over 85%. Due to the high TOC/TC ratio in the two cores, TC in the sediments also mainly exists as OCa, and the proportion of OCa is about 60%-80%. Away from the shore and relatively high primary production in upper waters are the main reasons that OCa is predominant among all burial OC in sediments of the central Yellow Sea mud area. Burial of OC in this mud area is probably mainly influenced by the human activities. Although the economic development during the late 19th century caused by the first industrial revolution in China did not obviously increase the TOC burial fluxes in the sediments, the rise of industry and agriculture after the founding of new China has clearly increased the TOC burial flux since 1950s. Otherwise, we also realize that among TC burial fluxes, TIC account for about 10%-30% in sediments of the central Yellow Sea mud area, so its burial could not be simply ignored here. Distinct from TOC burial, long-term TIC burial fluxes variations relate with climate changes more closely: the East Asian summer monsoon may influence the strength of the Huanghe River (Yellow River) flood, which could further affect the transport of terrestrial IC from land to the central Yellow Sea as well as the burial of these IC in the sediments. 展开更多
关键词 the central Yellow Sea mud area organic carbon burial flux source long-term changes human activities
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全球变暖对青藏高原不同补给类型湖泊生产力的影响 被引量:1
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作者 张玉枝 马雪洋 +1 位作者 李倩 任娇 《地理科学》 CSSCI CSCD 北大核心 2024年第2期351-358,共8页
研究以青藏高原阿翁错和托素湖湖泊沉积物为研究对象,通过多指标(总有机碳含量、有机碳同位素和有机碳埋藏速率等)综合分析,重建不同补给类型湖泊的生产力变化及碳循环过程。结果显示:全球变暖对不同类型湖泊的生产力的影响存在显著差... 研究以青藏高原阿翁错和托素湖湖泊沉积物为研究对象,通过多指标(总有机碳含量、有机碳同位素和有机碳埋藏速率等)综合分析,重建不同补给类型湖泊的生产力变化及碳循环过程。结果显示:全球变暖对不同类型湖泊的生产力的影响存在显著差异。在以降水和冰川融水为主要补给源的阿翁错,全球变暖造成冰川融水补给增加。当指示冰川融水补给量变化的δ^(18)O_(carb)值逐渐偏负时,湖泊沉积物TOC含量逐渐升高;指示冰川融水输入造成湖泊面积持续扩张,营养物质增加,湖泊生产力提高;当湖泊面积扩张较快,即冰川融水在短时间内快速输入时,TOC含量下降,可能是由于当冰川融水输入过多,造成湖水温度下降过快时,底栖藻类生产力下降,进而湖泊固碳能力下降。对于受人类活动影响的托素湖,全球变暖对湖泊水文过程及生产力的影响较小,δ^(18)O_(carb)值变化主要受控于农业灌溉活动引起的湖泊补给水量的变化。当δ^(18)O_(carb)值升高时,TOC含量增加;推测是由于农业灌溉耗水量增加导致湖泊补给水量减少,湖泊水位下降,湖泊底部接收到更多光照,湖泊生产力上升,固碳能力随之上升。 展开更多
关键词 青藏高原 湖泊 气候变化 湖泊生产力 有机碳埋藏速率
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长江口滨海湿地有机碳循环过程及影响因素研究进展 被引量:1
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作者 杨中元 娄厦 +3 位作者 陈仕哲 Irina Fedorova Viktorovna Dorzhievna Radnaeva Larisa Elena Nikitina 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期303-312,共10页
滨海湿地是“蓝碳生态系统”的重要组成部分。综述了长江口滨海湿地土壤有机碳时空分布及含量、碳汇速率、有机碳横向输入输出通量及量化方法、有机碳循环定量分析模型以及有机碳储量和组分对不同影响因素所做出的动态响应规律,发现在... 滨海湿地是“蓝碳生态系统”的重要组成部分。综述了长江口滨海湿地土壤有机碳时空分布及含量、碳汇速率、有机碳横向输入输出通量及量化方法、有机碳循环定量分析模型以及有机碳储量和组分对不同影响因素所做出的动态响应规律,发现在土壤有机碳水平空间分布上,崇西湿地>崇明东滩>九段沙>南汇潮滩;有机碳通量和浓度变化主要受到植物生物量和结构、水和土壤的理化性质、陆源输入和潮汐动力、间隙水交换以及人类活动和全球气候变化的影响。未来应加强长江口湿地土壤碳库和有机碳输运通量统一观测,准确量化各主要因素对有机碳的贡献,这对研究盐沼湿地的碳循环机理和碳汇评估具有重要意义。 展开更多
关键词 长江口湿地 有机碳时空分布 垂向埋藏速率 横向输送通量 影响因素 碳汇评估
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全新世长江河口铁结合沉积有机碳的埋藏及其影响因素的研究
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作者 陈佳琪 肖文杰 +5 位作者 刘志良 潘思尚 年小美 张卫国 葛黄敏 许云平 《海洋与湖沼》 CAS CSCD 北大核心 2024年第5期1139-1149,共11页
探究海洋沉积物中有机碳的来源、埋藏通量及其稳定机制对于理解全球碳循环具有重要的意义。河口连结陆地和海洋两大碳库,是全球碳循环的关键地带。前人研究发现活性铁(FeR)在沉积有机碳的保存中扮演着重要角色。尽管长江口及其邻近东海... 探究海洋沉积物中有机碳的来源、埋藏通量及其稳定机制对于理解全球碳循环具有重要的意义。河口连结陆地和海洋两大碳库,是全球碳循环的关键地带。前人研究发现活性铁(FeR)在沉积有机碳的保存中扮演着重要角色。尽管长江口及其邻近东海区域的碳循环已经被广泛研究,但关于FeR在地质时间尺度上如何影响沉积有机碳的埋藏过程尚不清楚。文章对长江口横沙岛采集的一根40 m长的沉积柱样(HSD22)进行了分析,探讨了在全新世长江口沉积环境发生明显变化的三个阶段(潮滩相、河口湾-浅海相、三角洲相)期间总有机碳(TOC)和铁结合有机碳(FeR-OC)含量及其稳定碳同位素(δ13C)的变化及其影响因素。研究结果显示,在潮滩相、河口湾-浅海相和三角洲相,FeR-OC含量分别为0.04%±0.02%、0.08%±0.04%和0.09%±0.06%,占TOC的比例分别为6.73%、12.73%和12.06%。这一研究表明,在全新世期间,长江河口区约有11.72%±6.03%的沉积有机碳是通过与铁结合来保存埋藏的,凸显了FeR在河口湿地有机碳保存机制中的重要性。基于δ13C端元混合模型估算发现FeROC以陆源有机碳为主,但在不同的沉积相间波动明显。这些发现强调了河口湿地FeR矿物在有机碳保护过程中受到有机碳来源和埋藏条件的影响。 展开更多
关键词 铁结合有机碳 活性铁 不同沉积相 碳埋藏通量 河口湿地
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近60年来洪泽湖的碳埋藏特征
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作者 戚甲豪 刘泰北 赵华 《水文地质工程地质》 CAS CSCD 北大核心 2024年第4期66-76,共11页
湖泊是重要的陆地生态系统碳汇。目前我国大部分湖泊碳埋藏研究仅考虑有机碳埋藏,多忽略无机碳埋藏,这会导致湖泊总碳埋藏能力被低估,该情况在湿润的东部平原区尤为显著。为了全面了解东部平原湖泊碳埋藏特征,更加合理地评估有机碳埋藏... 湖泊是重要的陆地生态系统碳汇。目前我国大部分湖泊碳埋藏研究仅考虑有机碳埋藏,多忽略无机碳埋藏,这会导致湖泊总碳埋藏能力被低估,该情况在湿润的东部平原区尤为显著。为了全面了解东部平原湖泊碳埋藏特征,更加合理地评估有机碳埋藏和无机碳埋藏对总碳埋藏的贡献,以东部平原区的代表性湖泊洪泽湖为研究对象,在^(210)Pb-^(137)Cs年代序列基础上,结合沉积物中的C/N、碳同位素特征等,对洪泽湖典型岩心(编号HZH-12)以及其他12个表层沉积物中的有机碳、无机碳时空变化进行分析,探究了近60 a来洪泽湖沉积物的碳埋藏特征。结果表明:(1)C/N和δ^(13)C显示内源有机碳是洪泽湖的主要有机碳来源;过去60 a有机碳和无机碳埋藏速率具有明显协同变化特征(R2=0.76,p<0.001),意味着无机碳可能源自浮游藻类光合作用导致的次生碳酸盐沉积。(2)有机碳和无机碳对比结果显示,洪泽湖无机碳含量(1.09%)明显高于有机碳(0.61%);无机碳埋藏速率为34.27 g/(m^(2)·a),要远高于25.27 g/(m^(2)·a)的有机碳埋藏速率。总的来说,洪泽湖有机碳在总碳埋藏中占比为42.4%,而无机碳在总碳埋藏中占比高达57.6%,这意味着忽略无机碳埋藏可能导致东部平原湖泊碳埋藏能力被极大低估。未来该区域的湖泊碳埋藏研究需要兼顾有机碳和无机碳埋藏。 展开更多
关键词 碳埋藏 有机碳 无机碳 洪泽湖
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Assessment on Redox Conditions and Organic Burial of Siliciferous Sediments at the Latest Permian Dalong Formation in Shangsi,Sichuan,South China 被引量:12
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作者 周炼 张海强 +2 位作者 王瑾 黄俊华 解习农 《Journal of China University of Geosciences》 SCIE CSCD 2008年第5期496-506,共11页
The redox sensitive elements, molybdenum (Mo) and uranium (U), in marine sediments from the latest Permian Dalong (大隆) Formation at the Shangsi (上寺) Section, Northeast Sichnan (四川), South China, were a... The redox sensitive elements, molybdenum (Mo) and uranium (U), in marine sediments from the latest Permian Dalong (大隆) Formation at the Shangsi (上寺) Section, Northeast Sichnan (四川), South China, were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) to determine their response to a range of redox conditions, and to estimate the organic carbon burial rate. On the basis of the correlation between anthigenic Mo abundance and organic carbon content in modern oceans, the organic carbon burial rates were calculated for the rocks at Dalong Formation, ranging from 0.48-125.83 mmol/(m^2.d), which shows a larger range than the mineralization rate of organic carbon at the continental margins (1.6-4.23 mmol/(m^2-d)). The Zr-normalized Mo and U abundances show large fluctuations in the entire section. The maxima of Zr-normalized Mo abundance and thus the maxima of the organic carbon burial rates were observed at the interval between the 155th and 156th beds (404-407 m above the base of Middle Permian). A decrease (the minimum) in U/Mo ratios is present in this interval. It is speculated that the oxygen-limited conditions and ultimately anoxia or euxinia may develop within this depth interval. In contrast, an enhanced enrichment of Zr-normalized U abundance is found, in association with less enrichment in Zr-normalized Mo abundance in the interval from the 151st to 154th beds (395-404 m above the base of Middle Permian), inferring the dominance of a suboxic/anoxic depositional condition (denitrifying condition), or without free H2S. The presence of small quantities of dissolved oxygen may have caused the solubilization and loss of Mo from sediments. It is proposed that the multiple cycles of abrupt oxidation and reduction due to the upwelling at this interval lead to the enhanced accumulation of authigenic U, but less enrichment of Mo. A decrease in the contents of U, Mo, and TOC is found above the 157th bed (407 m above the base of Middle Permian), in association with the enhanced U/Mo ratio, suggesting the overall oxic conditions at the end of the Dalong Formation. 展开更多
关键词 molybdenum URANIUM organic carbon burial rate Dalong Formation.
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河道型水库沉积物有机碳空间分布特征及其埋藏效应
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作者 秦勇 孙鹤 +4 位作者 李姗泽 顾菲 曹珍 李小影 阎腾飞 《水利水电技术(中英文)》 北大核心 2024年第2期123-132,共10页
【目的】河流筑坝对有机碳具有重要的拦截作用,影响内陆水体碳循环。目前,河道型水库沉积物有机碳空间分布特征和自生有机碳埋藏通量仍不明确。【方法】采用沉积物柱芯法、沉积物物理化学参数和碳同位素二元混合模型,对河道型水库(银盘... 【目的】河流筑坝对有机碳具有重要的拦截作用,影响内陆水体碳循环。目前,河道型水库沉积物有机碳空间分布特征和自生有机碳埋藏通量仍不明确。【方法】采用沉积物柱芯法、沉积物物理化学参数和碳同位素二元混合模型,对河道型水库(银盘水库)沉积物有机碳埋藏开展了调研。【结果】结果显示:银盘水库沉积物有机碳含量变化范围为0.99%~1.32%,库中和坝前沉积柱有机碳含量均值分别为1.12%和1.16%;内源有机碳与总磷呈现显著正相关;有机碳埋藏速率变化范围为98.7~348.9 g C·m^(-2)·a^(-1),平均值为223.8 g C·m^(-2)·a^(-1),有机碳埋藏通量和内源有机碳埋藏通量分别为2.5×10^(9)g C·a^(-1)和1.8×10^(9)g C·a^(-1);内源有机碳对沉积物总有机碳的贡献比例为69.0%~75.2%,平均值为71.5%。【结论】结果表明:河道型水库沉积柱有机碳含量从库中到坝前没有明显变化;水库内源有机质的生成与营养盐输入和水体滞留时间密切相关;银盘水库有机碳埋藏通量相当于全球水库有机碳埋藏通量的0.04‰,河道型水库是个重要的潜在碳汇。研究结果能够为河道型水库碳埋藏研究和水电清洁型评估提供参考依据。 展开更多
关键词 河道型水库 碳循环 有机碳埋藏 碳埋藏通量 沉积物柱芯 长江流域 影响因素
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利用声学调查法和沉积柱理化参数评估河道型水库碳埋藏通量
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作者 秦勇 付文军 +4 位作者 包宇飞 顾菲 厉励 曹珍 李小影 《湖泊科学》 EI CAS CSCD 北大核心 2024年第6期1820-1833,共14页
河道型水库对有机碳具有重要的拦截作用,影响内陆水体碳循环。然而,河道型水库水体滞留时间较短,其碳埋藏效应容易被忽视。受野外观测方法的限制,准确地评估河道型水库碳汇潜力面临挑战。声学调查法能够全面反映水库沉积物淤积分布,是... 河道型水库对有机碳具有重要的拦截作用,影响内陆水体碳循环。然而,河道型水库水体滞留时间较短,其碳埋藏效应容易被忽视。受野外观测方法的限制,准确地评估河道型水库碳汇潜力面临挑战。声学调查法能够全面反映水库沉积物淤积分布,是一种快速、经济和准确的水库碳埋藏评估方法。本研究采用声学调查法、沉积柱理化参数和碳同位素技术,对乌江流域河道型水库(思林水库)有机碳埋藏开展了调研。结果表明,思林水库沉积物厚度变化范围为0~3.53 m,不规则的水下地形导致沉积物淤积分布具有高度的空间异质性。思林水库沉积物有机碳含量、C/N摩尔比和δ13 C值变化范围分别为1.03%~3.40%、4.62~9.14和-28.5‰~-23.8‰,平均值分别为1.93%、7.24和-26.6‰,显示沉积物有机碳主要来源于水生浮游植物。思林水库内源有机碳对沉积物总有机碳的贡献比例范围为21.2%~85.1%,平均值为60.1%。沉积物内源有机质含量与营养盐氮磷浓度呈显著正相关,表明营养盐氮磷的输入促进了内源有机质的生成。思林水库有机碳埋藏速率变化范围为0~12133.4 g/(m^(2)·a),平均值为1429.8 g/(m^(2)·a),有机碳埋藏通量为2.16×10^(10)g/a,相当于全球水库有机碳埋藏通量的0.36‰,表明河道型水库碳汇潜力不容忽视。思林水库内源有机碳通量为1.30×10^(10)g/a,相当于水气界面CO 2释放通量的0.32倍。本研究水库和其他研究的水库有机碳埋藏速率与水体滞留时间呈对数函数关系,该经验函数将有助于估算全球水库有机碳埋藏速率。 展开更多
关键词 河道型水库 思林水库 有机碳埋藏 声学调查法 柱状沉积物 碳同位素 水体滞留时间
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茅埏岛红树林沉积物有机碳埋藏特征解析
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作者 于洋 水柏年 +4 位作者 吕聪聪 李滨 李雪丽 魏珍 胡成业 《中国环境科学》 EI CAS CSCD 北大核心 2024年第8期4539-4546,共8页
以茅埏岛北部红树林湿地为研究区域,旨在探究红树林湿地沉积物有机碳埋藏特征和来源.基于放射性同位素(^(210)Pb)采用恒定沉积速率模式分析沉积速率(SAR)、有机碳密度、埋藏速率(OCAR)、有机碳潜在来源及贡献率.茅埏岛红树林湿地的沉积... 以茅埏岛北部红树林湿地为研究区域,旨在探究红树林湿地沉积物有机碳埋藏特征和来源.基于放射性同位素(^(210)Pb)采用恒定沉积速率模式分析沉积速率(SAR)、有机碳密度、埋藏速率(OCAR)、有机碳潜在来源及贡献率.茅埏岛红树林湿地的沉积速率约为1.8cm/a.沉积物以粉砂和黏土为主,粒径随深度变化基本保持稳定,且过剩^(210)Pb活度与深度之间具有较好的相关性,表明沉积环境较为稳定.沉积物有机碳密度平均值为0.66g/cm^(3),埋藏速率为120.01g/(m^(2)·a).通过碳氮稳定同位素分布特征结合多线性混合模型(IsoSource)可知,沉积物有机碳来源总体以海陆混合来源为主,其中海源占比50.3%,陆源占比33.4%,树源贡献占比16.3%;表层沉积物以陆源和树源输入为主,树源贡献率最高达46.4%.红树林植被组成、成林时间等是影响沉积物有机碳埋藏重要因素. 展开更多
关键词 红树林湿地 有机碳 沉积物 埋藏速率
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A large carbon pool in lake sediments over the arid/semiarid region, NW China 被引量:12
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作者 Jianghu Lan Hai Xu +3 位作者 Bin Liu Enguo Sheng Jiangtao Zhao Keke Yu 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第3期289-298,共10页
Carbon burial in lake sediments is an important component of the global carbon cycle. However, little is known about the magnitude of carbon sequestered in lake sediments over the arid/semiarid region of China(ASAC).I... Carbon burial in lake sediments is an important component of the global carbon cycle. However, little is known about the magnitude of carbon sequestered in lake sediments over the arid/semiarid region of China(ASAC).In this study, we estimate both organic and inorganic carbon burial since *AD 1800 based on nine lakes in ASAC,and discuss the most plausible factors controlling carbon burial. Our estimates show that the annual organic carbon burial rate(OCBR) ranges from 5.3 to 129.8 g cm-2year-1(weighted mean of 49.9 g cm-2year-1), leading to a standing stock of 1.1–24.0 kg cm-2(weighted mean of 8.6 kg cm-2)and a regional sum of *108 Tg organic carbon sequestered since *AD 1800. The annual inorganic carbon burial rate(ICBR) ranges from 11.4 to 124.0 g cm-2year-1(weighted mean of 48.3 g cm-2year-1), which is slightly lower than OCBR. The inorganic carbon standing stock ranges from2.4 to 26.0 kg cm-2(weighted mean of 8.1 kg cm-2),resulting in a sum of *101 Tg regional inorganic carbon burial since *AD 1800, which is slightly lower than the organic carbon sequestration. OCBR in ASAC shows a continuously increasing trend since *AD 1950, which is possibly due to the high autochthonous and allochthonous primary production and subsequently high sedimentation rate in the lakes. This increasing carbon burial is possibly related to both climatic changes and enhanced anthropogenic activities, such as land use change, deforestation, and eutrophication in the lake. Furthermore, OCBR and ICBR are expected to continuously increase under the scenario of increasing precipitation and runoff and enhanced anthropogenic activities.The results of this research show that the buried carbon in lake sediments of the ASAC region constitutes a significant and large carbon pool, which should be considered and integrated into the global carbon cycle. 展开更多
关键词 西北干旱半干旱地区 湖泊沉积物 碳库 缓冲寄存器 全球碳循环 加权平均 输出通道 显示控制
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近百年来异龙湖有机碳和无机碳埋藏响应水体富营养化的协同变化特征 被引量:3
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作者 李平 陈光杰 +11 位作者 孔令阳 黄林培 王旭 杨关绍 索旗 李静 王露 韩桥花 周起 郭雯 李蕊 张涛 《中国环境科学》 EI CAS CSCD 北大核心 2023年第10期5489-5502,共14页
湖泊碳埋藏模式及其动态变化对陆地碳汇通量与全球碳收支估算具有重要影响,然而现有湖泊碳埋藏评估主要基于有机碳的埋藏模式,缺乏对无机碳埋藏以及有机碳-无机碳协同变化过程的系统评估.本文通过对云南岩溶区异龙湖开展沉积物岩芯样品... 湖泊碳埋藏模式及其动态变化对陆地碳汇通量与全球碳收支估算具有重要影响,然而现有湖泊碳埋藏评估主要基于有机碳的埋藏模式,缺乏对无机碳埋藏以及有机碳-无机碳协同变化过程的系统评估.本文通过对云南岩溶区异龙湖开展沉积物岩芯样品的多指标分析和湖盆3个点位的记录对比,结合210Pb、137Cs年代学序列,识别了1900年以来异龙湖有机碳和无机碳埋藏通量的变化历史和空间特征,并甄别了二者协同变化的主要特征及其转化路径.结果表明,近百年来流域开发导致的营养盐长期输入(如沉积物氮和磷的持续富集)显著提高了异龙湖的内源初级生产力,表现为1900~2020年间沉积物藻类色素含量持续增加,蓝藻叶黄素浓度由~7.02μg/g显著增加到~38.99μg/g.同期有机碳和无机碳的埋藏通量均出现持续的上升趋势,且两者的同步变化特征显著(r=0.98~0.99,P<0.001).回归分析表明,藻类生物量是碳埋藏通量上升的主要驱动因子(R^(2)=0.33~0.91,P<0.001),指示了藻类光合作用以及“生物碳泵”效应对碳埋藏过程的驱动作用.在流域地表物质输入强度总体下降(如磁化率信号和沉积物C:N比值的减小)的背景下,藻类生物量和内源有机碳的持续上升导致了有机质矿化过程中自生碳酸盐的转化作用明显增加(如无机碳δ13C信号的持续下降),进而促进了有机碳与无机碳埋藏通量的协同增长.上述结果表明,水体富营养化过程促进形成了有机碳和无机碳埋藏通量同步增加的长期模式,加强了异龙湖有机碳和无机碳埋藏过程的耦合作用.因此在人类活动与气候变化持续的背景下,对岩溶地区湖泊碳埋藏模式的科学评估需要关注无机碳埋藏过程及其对陆地碳汇通量的动态影响. 展开更多
关键词 富营养化 碳埋藏 无机碳 协同变化 异龙湖
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塔里木盆地深层碳酸盐岩建造-改造作用与多类型储层有序性分布 被引量:5
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作者 樊太亮 高志前 吴俊 《地学前缘》 EI CAS CSCD 北大核心 2023年第4期1-18,共18页
我国深层海相碳酸盐具有埋藏深度大、地质时代老、地质演化过程复杂等特点,其储层形成和分布受到众多因素制约,是海相油气勘探面临的关键问题之一。本文总结了团队在塔里木盆地长期研究成果,从深层碳酸盐岩建造和改造作用出发,揭示塔里... 我国深层海相碳酸盐具有埋藏深度大、地质时代老、地质演化过程复杂等特点,其储层形成和分布受到众多因素制约,是海相油气勘探面临的关键问题之一。本文总结了团队在塔里木盆地长期研究成果,从深层碳酸盐岩建造和改造作用出发,揭示塔里木盆地多类型碳酸盐岩储层的主要发育条件和有序性分布。(1)塔里木盆地台地格局、地层发育演化及后期的埋藏与改造,均是盆缘构造事件在盆内的构造-沉积作用响应。早古生代盆地经历了地貌张裂分化与小型裂陷群形成、地貌挤压分化与层间不整合发育、古隆起与大型不整合作用、多期不整合叠加与古隆起埋藏改造等演化过程。(2)碳酸盐岩台地沉积过程中存在着不同尺度、不同类型的分异演化作用,可分为雏形期、建造期、鼎盛期和分解-消亡期,相应的台地边缘演化经历了缓斜坡、进积镶边、加积镶边和退积陡坡等建造过程,控制着台缘礁滩、台内滩、早期白云岩化潮坪等有利于规模化储集岩发育的沉积相带分布。(3)多级次不整合和断裂-流体改造是优质储层形成的重要机制。多期区域构造活动和周期性海平面变化控制了不同级别的不整合面发育,海平面下降主导的层序界面导致碳酸盐岩周期性暴露,形成了不同规模的层间岩溶和同沉积岩溶,区域构造运动所对应的大型不整合控制了大规模表生岩溶储层发育,不同规模的断裂和裂缝既是储层发育带,也是流体活动和改造的主要区带。(4)塔北-顺北地区不整合发育强度和断裂活动强度由北向南有序变化,控制了碳酸盐岩储层类型与分布的有序性变化,自北向南依次发育雅克拉断凸潜山型白云岩储层、塔河主体区古风化壳型岩溶储层、塔河斜坡区层控型岩溶储层、塔河覆盖区断溶型储层和顺北断控型储层,反映出由剥蚀区至覆盖区不整合控储作用逐渐变弱,而断裂控储作用增强。 展开更多
关键词 深层碳酸盐岩 建造-改造作用 储层有序分布 塔里木盆地
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长江古河谷早中全新世沉积物碳埋藏通量与来源解析 被引量:1
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作者 苟富刚 《海洋学报》 CAS CSCD 北大核心 2023年第4期95-108,共14页
为了研究长江古河谷地区早中全新世沉积物的碳埋藏速率及来源,进行了ZK1孔沉积物总有机碳(TOC)、总氮(TN)及δ^(13)C的测定,结合AMS^(14)C(植物碎屑、贝壳)测年、有孔虫及粒度数据,分析了长江古河谷碳埋藏的时空分布特征与TOC来源。采... 为了研究长江古河谷地区早中全新世沉积物的碳埋藏速率及来源,进行了ZK1孔沉积物总有机碳(TOC)、总氮(TN)及δ^(13)C的测定,结合AMS^(14)C(植物碎屑、贝壳)测年、有孔虫及粒度数据,分析了长江古河谷碳埋藏的时空分布特征与TOC来源。采用历史地理学、沉积地质学结合测年数据进行了年代地层划分,自下而上分别为U1潮汐河道、U2河口湾、U3潮流砂脊和U4前三角洲。沉积物受到水深、径流、河口余环流、潮流、波浪、风暴与再矿化等作用或因素影响,TOC平均值为0.41%,低于长江河口表层沉积物基准值0.46%。ZK1碳埋藏通量(TOC_(BF))介于7.4~110.5g/(m^(2)·a)之间,差异较大。TOC_(BF)数值主要受控于沉积速率。δ^(13)C与TOC/TN(C/N)投影点结果表明,TOC来源表现为多源特征,且整体表现为偏陆源特征。C/N与δ^(13)C线性拟合相关性高,适合采用C/N与δ^(13)C进行TOC来源的定量分析。基于C/N与δ^(13)C采用三端源模型进行了TOC来源分析。U2、U3沉积期处于全新世大暖期,其海源碳与陆源碳较U1、U2沉积单元高,这主要与海洋、陆地初级生产力的提高有关。ZK1海洋浮游植物对TOC的贡献量平均值为31%。河口浮游植物对TOC的贡献量平均值为31%。陆源有机碳对TOC的贡献量平均值为38%。整体来看,陆源有机碳的贡献量大于河口浮游植物与海洋浮游植物的贡献量,这与图解法的分析结果基本一致。 展开更多
关键词 有机碳 有孔虫 埋藏速率 沉积环境 AMS^(14)C
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海湾地质碳汇网格化计算——以三门湾为例 被引量:1
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作者 张旭 田元 +5 位作者 王建强 张鹏辉 陈彬 田雨晴 董超 印萍 《海洋地质前沿》 CSCD 北大核心 2023年第6期46-54,共9页
河口海湾地区因沉积物富含有机质和高沉积速率成为地球上重要的碳汇区,在专题性碳汇调查不足情况下,如何更好地发掘前人地质调查数据资源,科学计算河口海湾地质碳埋藏能力,是科学评价海洋碳汇能力支撑双碳目标的重要挑战。以浙江省三门... 河口海湾地区因沉积物富含有机质和高沉积速率成为地球上重要的碳汇区,在专题性碳汇调查不足情况下,如何更好地发掘前人地质调查数据资源,科学计算河口海湾地质碳埋藏能力,是科学评价海洋碳汇能力支撑双碳目标的重要挑战。以浙江省三门湾海域表层沉积物和沉积柱状样品为研究对象,综合运用粒度分析、有机地球化学分析、210Pb和137Cs测年等测试手段,充分考虑海湾地区海底地形复杂、海陆交互强烈、人类活动活跃等典型特征,探索海湾碳汇网格化计算方法,建立了海湾地质碳汇评估模型。计算表明:三门湾有机碳年埋藏速率为64.04 gC·m^(−2)·a^(−1),有机碳年埋藏量达89.71 GgC,河口和潮滩区有机碳埋藏速率高,为74.02 gC·m^(−2)·a^(−1),海湾中部和深水区为52.93 gC·m^(−2)·a^(−1)。 展开更多
关键词 三门湾 地质碳汇 网格化 有机碳埋藏速率
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