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Zhang J, Hao Q, Li Q, Zhao X, Fu X, Wang W, He D, Li Y, Zhang Z, Zhang X, Song Z. Source identification of sedimentary organic carbon in coastal wetlands of the western Bohai Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 913:169282. [PMID: 38141989 DOI: 10.1016/j.scitotenv.2023.169282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 12/05/2023] [Accepted: 12/09/2023] [Indexed: 12/25/2023]
Abstract
Coastal wetlands play a vital role in mitigating climate change, yet the characteristics of buried organic carbon (OC) and carbon cycling are limited due to difficulties in assessing the composition of OC from different sources (allochthonous vs. autochthonous). In this study, we analyzed the total organic carbon (TOC) to total nitrogen (TN) ratio (C/N), stable carbon isotope (δ13C) composition, and n-alkane content to distinguish different sources of OC in the surface sediments of the coastal wetlands on the western coast of the Bohai Sea. The coupling of the C/N ratio with δ13C and n-alkane biomarkers has been proved to be an effective tool for revealing OC sources. The three end-member Bayesian mixing model based on coupling C/N ratios with δ13C showed that the sedimentary OC was dominated by the contribution of terrestrial particulate organic matter (POM), followed by freshwater algae and marine phytoplankton, with relative contributions of 47 ± 21 %, 41 ± 18 % and 12 ± 17 %, respectively. The relative contributions of terrestrial plants, aquatic macrophytes and marine phytoplankton assessed by n-alkanes were 56 ± 8 %, 35 ± 9 % and 9 ± 5 % in the study area, respectively. The relatively high salinity levels and strong hydrodynamic conditions of the Beidagang Reservoir led to higher terrestrial plants source and lower aquatic macrophytes source than these of Qilihai Reservoir based on the assessment of n-alkanes. Both methods showed that sedimentary OC was mainly derived from terrestrial sources (plant-dominated), suggesting that vegetation plays a crucial role in storing carbon in coastal wetlands, thus, the coastal vegetation management needs to be strengthened in the future. Our findings provide insights into the origins and dynamics of OC in coastal wetlands on the western coast of the Bohai Sea and a significant scientific basis for future monitoring of the blue carbon budget balance in coastal wetlands.
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Affiliation(s)
- Juqin Zhang
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Qian Hao
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China.
| | - Qiang Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Xiangwei Zhao
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Xiaoli Fu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Weiqi Wang
- Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350117, China
| | - Ding He
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong SAR, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, Hong Kong SAR, China; State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Science, Wuhan 430071, China
| | - Yuan Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, China
| | - Zhenqing Zhang
- School of Geographic and Environmental Sciences, Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China; Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Xiaodong Zhang
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China.
| | - Zhaoliang Song
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
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Sun W, Niu X, Yin X, Duan Z, Xing L, Liu A, Ma Y, Gao P. Historical evolution of polycyclic aromatic hydrocarbon pollution in Chaihe Reservoir from 1863 to 2018. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 328:116944. [PMID: 36525734 DOI: 10.1016/j.jenvman.2022.116944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Pollution from polycyclic aromatic hydrocarbons (PAHs) spreads and changes worldwide. The pollution evolution in the regional water environment evolves in response to multiple factors, requiring considerable attention. PAH heterogeneity in the sediment core from Chaihe Reservoir was investigated to indicate dynamic changes in PAH pollution levels and sources and propose recommendations for controlling PAHs. Dynamic PAH patterns showed that the overall decline in PAH pollution was in association with local anthropogenic activities, temperature, and precipitation over the period 1863-2018. Nevertheless, coal, oil, and natural gas consumptions still played significant roles in transferring PAHs to the reservoir. Meanwhile, there were dominant local origins, including grass, wood, and coal combustion. The results highlight that the joint action of natural and anthropogenic interventions mitigated PAH pollution in the reservoir. Promoting improved fuels, new energy vehicles, and cleaner energy may further lower PAH pollution.
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Affiliation(s)
- Wenxian Sun
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255049, China.
| | - Xiaoyin Niu
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China.
| | - Xianwei Yin
- Zibo Eco-environmental Monitoring Centre of Shandong Province, Zibo, 255049, China.
| | - Zhenhao Duan
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255049, China.
| | - Liqi Xing
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255049, China.
| | - Aiju Liu
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China.
| | - Yanfei Ma
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China.
| | - Peiling Gao
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, China.
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Sun W, Zhou Z, Yin X, Wang Y, Teng H, Liu A, Ma Y, Niu X. Response of sedimentation rate to environmental evolution in Da River Reservoir in Southwest China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:76739-76751. [PMID: 35670938 DOI: 10.1007/s11356-022-20801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 05/10/2022] [Indexed: 06/15/2023]
Abstract
Lake sediment records the evolution process of the interaction between human and nature. It is important to master the lacustrine sedimentation rate for the ecological environment assessment of catchment. A 60-cm sediment core was collected in the Da River Reservoir during 2019 to analyze radionuclides (210Pb and 137Cs) massic activities, grain size, total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and metals (Mn, Cu, Al, and Pb) mass fractions to reconstruct the response of sedimentation rate to environmental evolution. The environmental changes in the small catchment were classified into the following three stages through cluster analysis (CA) for geochemical parameters in the sediment core: phase I (1881-1985), phase II (1987-1999), and phase III (2000-2018). The average depth sedimentation rates (ADSRs) of the three stages were 0.33, 0.90, and 1.50 cm/year, respectively. The sedimentation rates increased from the bottom to the surface layer, indicating that the exogenous inputs into the reservoir have been occurring. The sediment deposition in phase III was strongly disturbed by the environmental changes (such as warmer climate and intensified land use). Therefore, sedimentation rates showed a rapid increase. Both Pearson correlation analysis and redundancy analysis (RDA) showed that sedimentation rates were positively correlated with climatic factors, particle size, nutrients and metals mass fractions, elemental ratios, and socioeconomic parameters. Sedimentation rates show high sensitivity to anthropogenic activities and climatic change, which can be used to reconstruct the environmental evolution process at a small catchment scale.
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Affiliation(s)
- Wenxian Sun
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, 255049, People's Republic of China
| | - Zike Zhou
- LongYou No.2 Senior High School, Quzhou, 324400, People's Republic of China
| | - Xianwei Yin
- Zibo Ecological Environment Quality Control Service Center, Zibo, 255049, People's Republic of China
| | - Yongping Wang
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, 255049, People's Republic of China
| | - Haowei Teng
- School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, 255049, People's Republic of China
| | - Aiju Liu
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo, 255049, People's Republic of China
| | - Yanfei Ma
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo, 255049, People's Republic of China
| | - Xiaoyin Niu
- School of Resources and Environmental Engineering, Shandong University of Technology, Zibo, 255049, People's Republic of China.
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Chen Y, Wang Y, Yu K, Zhao Z, Lang X. Occurrence characteristics and source appointment of polycyclic aromatic hydrocarbons and n-alkanes over the past 100 years in southwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 808:151905. [PMID: 34838905 DOI: 10.1016/j.scitotenv.2021.151905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/16/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
The extensive anthropogenic activities and their potential impacts during the Anthropocene have led to a research focus on the sedimentary record. In the present study, the occurrence and temporal variations in the fluxes and compositions of n-alkanes and polycyclic aromatic hydrocarbon (PAHs) were investigated in 210Pb-dated sediment cores from a small catchment near the outflow Tanglangchuan in the western Dianchi Lake, China. The continuing organic contamination (i.e. PAHs and n-alkanes) from inputs to outputs has been of concern. To trace the sources and driving forces, multi indicators were applied. Results showed that the total organic carbon (TOC) contents and C/N ratios varied in the range of 4.20-12.30 mg g-1 dw and 8.64-15.65, respectively, indicating algae- and terrestrial plant-derived organic matter (OM). The flux of Σn-alkanes ranged from 0.67 to 38.86 μg cm-2 a-1 with a peak in 2013. The long-chain n-alkanes (Σn-alk26-35) and short-chain n-alkanes (Σn-alk12-20) accounted for 44.02%-49.38% and 35.32%-41.49% of the Σn-alkanes, respectively. A bimodal distribution of n-alkanes was displayed in the sediments implying the sedimentary OM may be derived from a mixed source of endogenous and exogenous origin. The posterior peak (≥n-C26) compounds in the highest abundance were n-C31 or n-C33 with a significant odd-numbered C predominance, representing terrestrial plant-derived OM. Whereas n-C16 was rich in all sediment profiles reflecting crude oil or incompletely combusted fossil fuel-derived source. The indicators analysis showed an increasing trend of the contribution from terrestrial plants and wet to drought climate during 1873-2019. The sedimentary flux of ΣPAHs ranged between 11.71 and 1231.54 ng cm-2 a-1 and the percent of high-ring PAHs rose annually indicating enhanced anthropogenic activities. In the past 147 years, the results of present study highlight the influence of the agricultural and industrial economy on the catchment outlets.
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Affiliation(s)
- Yan Chen
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing 210023, China
| | - Yanhua Wang
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing 210023, China; Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, China.
| | - Kangkang Yu
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing 210023, China
| | - Zihan Zhao
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing 210023, China
| | - Xiulu Lang
- School of Geography, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing 210023, China
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He Y, Yang C, He W, Liu W, Xu F. New insights into spatiotemporal source apportionment of n-alkanes under mixed scenario: A pilot study on Lake Chaohu, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 742:140517. [PMID: 32623169 DOI: 10.1016/j.scitotenv.2020.140517] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/03/2020] [Accepted: 06/24/2020] [Indexed: 06/11/2023]
Abstract
N-alkanes are ideal molecular markers for the source apportionment of organic matter. However, the estimation of both biogenic and anthropogenic sources under mixed scenario using n-alkanes and their related proxies still remains an issue. In this study, we investigated spatiotemporal variations of n-alkanes in suspended particulate matter of Lake Chaohu for their source apportionment. Overall, Σ29 n-alkanes ranged from 324.1 to 113685 ng·L-1. C17H36 was the most abundant homologue and was followed by C18, C27 and C29 homologues. Carbon preference indexes (CPIs) in most samples (at least 85%) were < 3, indicating mixed sources of n-alkanes in Lake Chaohu. Therefore, biogenic and anthropogenic n-alkanes were separated by subtraction to avoid potential bias. Our results showed Σ biogenic and Σ anthropogenic n-alkanes ranged from 14.8 to 3531.6 ng·L-1 and 257.6 to 4938.5 ng·L-1, respectively. For biogenic n-alkanes, their carbon-chain distributions posed a preponderant peak at C17, indicating algae were the main contributors to biogenic n-alkanes in Lake Chaohu. Biogenic average chain length (ACLbio) was developed to quantify the contributions of different biogenic sources. We recommended ACLbio < 21 for algae dominance and ACLbio > 26 for terrestrial plant dominance. For anthropogenic n-alkanes, their carbon-chain distribution presented obviously spatiotemporal variations. The sources of anthropogenic n-alkanes in summer and winter were typical dominances of light petroleum and incomplete fossil fuel burning/heavy oil emission, respectively. New developed proxies, anthropogenic average chain length (ACLanthro) and the ratio of unit short- to long-carbon anthropogenic n-alkanes (L/H), are effective for quantifying the relative contributions of different anthropogenic sources. We recommend log10L/H > 0.5 and ACLanthro < 20.5 for light petroleum input dominance, log10L/H < -0.5 and ACLanthro > 26.5 for incomplete fossil fuel burning at high temperature/heavy oil emission dominance.
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Affiliation(s)
- Yong He
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Chen Yang
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Wei He
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Wenxiu Liu
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Fuliu Xu
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
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Historical Evolution of Sources and Pollution Levels of Heavy Metals in the Sediment of the Shuanglong Reservoir, China. WATER 2020. [DOI: 10.3390/w12071855] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
In this study, the concentrations of seven heavy metals (Cr, Ni, Cu, Zn, As, Hg, and Pb) and Pb isotope in a sediment core from the Shuanglong reservoir, Southwestern China, were investigated. Based on the constant rate of supply (CRS) model, the age span of a 60 cm sediment sample was determined to range from the years 1944 to 2015. Combined with chronology and heavy metal content, the evolution of the sources and pollution levels of heavy metals showed a changing trend composed of various stages. The sources of heavy metals transitioned from natural origins in 1944–1964 to industrial origins in 1965–2004. The subsequent reduction in heavy metal content was mainly due to the vigorous implementation of environmental protection policies from 2005 to 2012. In recent years (2013–2015), the heavy metal content has increased due to frequent human activity. Principal component analysis (PCA), correlation analysis, and the coefficient of variation (CV) analysis indicated that Cr, Ni, Cu, Zn, and As were derived from natural processes, Pb mainly came from automobile manufacturing, and Hg was mainly from industrial sources. The values of the geo-accumulation index (Ig), single pollution index (Pi), and single potential ecological risk index (Er) showed that the contamination of Hg and Pb was slight to moderate. Moreover, the values of the potential ecological risk index (RI), pollution load index (PLI), and Nemerow index (PN) indicated that the Shuanglong reservoir is under low ecological risk.
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Galoski CE, Jiménez Martínez AE, Schultz GB, Dos Santos I, Froehner S. Use of n-alkanes to trace erosion and main sources of sediments in a watershed in southern Brazil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 682:447-456. [PMID: 31128364 DOI: 10.1016/j.scitotenv.2019.05.209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
Erosive processes can transport sediments containing nutrients, heavy metals and contaminants of organic and inorganic origin into bodies of water, therefore affecting the local ecosystem and the population that benefits from the water sources. In order to better understand the origin of sediment sources and establish mitigation measures, the use of the sediment fingerprinting technique has been highlighted. Thus, the present work had as objective to apply n-alkanes in order to trace and understand the main sources of organic matter in sediments and associate the results with land and soil occupation. The study area is located in the municipality of Rio Negrinho - Brazil, in the Saci river basin. Soil samples were collected and classified according to their use and occupation, as well as and samples of local vegetation to be used as reference. The distribution of n-alkanes in the sediments was compared with the distribution found in the vegetation and soil. Previously, a distribution pattern of n-alkanes had been identified in all major vegetation used to trace the source of organic matter and hence the soil. The concentrations of total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP) and granulometry were also analyzed in the soil and sediment samples. Indexes between n-alkanes were used and applied to assess the source together with statistical analysis (PCA). In sum, the results showed that the sediments are mainly composed of Pinus taeda reforestation soils, as well as soil from the abandoned roads used to transport the cut trees, while the contribution of autochthonous sediments was found to be minimal. In this way, the fingerprint technique served as an auxiliary tool in order to establish measures for the good management of a river basin, bringing important information about the contributing sources of sediment to water bodies.
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Affiliation(s)
- Carlos Eduardo Galoski
- Department of Environmental Engineering, Federal University of Parana, Curitiba 81531-980, Brazil.
| | | | - Gilson Bauer Schultz
- Department of Geography, Federal University of Parana, Curitiba 81531-980, Brazil
| | - Irani Dos Santos
- Department of Geography, Federal University of Parana, Curitiba 81531-980, Brazil
| | - Sandro Froehner
- Department of Environmental Engineering, Federal University of Parana, Curitiba 81531-980, Brazil
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Liu C, Li Z, Chang X, Nie X, Liu L, Xiao H, Wang D, Peng H, Zeng G. Apportioning source of erosion-induced organic matter in the hilly-gully region of loess plateau in China: Insight from lipid biomarker and isotopic signature analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 621:1310-1319. [PMID: 29054640 DOI: 10.1016/j.scitotenv.2017.10.097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/10/2017] [Accepted: 10/11/2017] [Indexed: 06/07/2023]
Abstract
Understanding the dynamics of organic matter (OM) at global and local scales is one of the challenges in the environmental sciences and i.e. terrestrial biogeochemistry. The accurate identification of OM is an essential element to achieve this goal. In our study, a novel application for quantitatively apportioning sources of eroded sedimentary OM from an eco-geomorphologic perspective was shown successfully via a coupled molecular n-alkane biomarkers and stable isotopic signatures (13C and 15N) along with elemental compositions (TOC and TN) using a Bayesian mixing model (SIAR). Soil source samples were collected from different land use types (i.e., forests, grassland, cropland, and fallow) and gully, which were probably transported downstream along the steep terrain. Meanwhile, three soil profiles with a total of 90 sediment samples were also sampled in check dam. The results indicated that cropland was the main sedimentary OM source in this catchment, contributing 29.5%, whereas the forests, grassland, fallow and gully contributed 12.17%, 15.39%, 21.53% and 21.85%, respectively. Although the molecular biomarker as a tracer was not valid solely, the combined approaches of n-alkanes biomarker and bulk parameters were efficient complements in tracing OM source in a hilly-gully region on the Loess Plateau of China.
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Affiliation(s)
- Chun Liu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shaanxi 712100, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Zhongwu Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shaanxi 712100, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Xiaofeng Chang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shaanxi 712100, PR China
| | - Xiaodong Nie
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou, 510650, PR China
| | - Lin Liu
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shaanxi 712100, PR China
| | - Haibing Xiao
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shaanxi 712100, PR China
| | - Danyang Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Hao Peng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
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Liu C, Dong Y, Li Z, Chang X, Nie X, Liu L, Xiao H, Bashir H. Tracing the source of sedimentary organic carbon in the Loess Plateau of China: An integrated elemental ratio, stable carbon signatures, and radioactive isotopes approach. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 167:201-210. [PMID: 27843064 DOI: 10.1016/j.jenvrad.2016.10.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 10/23/2016] [Accepted: 10/25/2016] [Indexed: 06/06/2023]
Abstract
Soil erosion, which will induce the redistribution of soil and associated soil organic carbon (SOC) on the Earth's surface, is of critically importance for biogeochemical cycling of essential elements and terrestrial carbon sequestration. Despite the importance of soil erosion, surprisingly few studies have evaluated the sources of eroded carbon (C). This study used natural abundance levels of the stable isotope signature (13C) and radioactive isotopes (137Cs and 210Pbex), along with elements ratio (C/N) based on a two end member mixing model to qualitatively and quantitatively identify the sources of sedimentary OC retained by check dam in the Qiaozigou small watershed in the Loess Plateau, China. Sediment profiles (0-200 cm) captured at natural depositional area of the basin was compared to possible source materials, which included: superficial Loess mineral soils (0-20 cm) from three land use types [i.e., grassland (Medicago sativa), forestland (Robinia pseudoacacia.), shrubland (Prunus sibirica), and gully land (Loess parent material.)]. The results demonstrated that SOC in sediments showed significantly negative correlation with pH (P < 0.01), and positive correlation with soil water content (SWC) (P < 0.05). The sedimentary OC was not derived from grasslands or gullies. Forestland and shrubland were two main sources of eroded organic carbon within the surface sediment (0-60 cm deep), except for that in the 20-40 cm soil layer. Radionuclides analyses also implied that the surface sediments retained by check-dams mainly originated from soils of forestland and shrubland. Results of the two end-member mixing model demonstrated that more than 50% SOC (mean probability estimate (MPE) 50.13% via 13C and 60.53% via C/N) in surface sediment (0-20 cm deep) derived from forestland, whereas subsurface sedimentary SOC (20-200 cm) mainly resulted from shrubland (MPE > 50%). Although uncertainties on the sources of SOC in deep soils exist, the soil organic δ13C and C/N is still an effective indicator for sources of sedimentary organic carbon in the deposition zone in the short term (<10 years).
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Affiliation(s)
- Chun Liu
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shanxi, 712100, PR China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Yuting Dong
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shanxi, 712100, PR China; Tianshui Soil and Water Conservation Experimental Station, Yellow River Conservancy Commission, Tianshui, Gansu Province, 741000, PR China.
| | - Zhongwu Li
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shanxi, 712100, PR China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Xiaofeng Chang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shanxi, 712100, PR China
| | - Xiaodong Nie
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Lin Liu
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shanxi, 712100, PR China
| | - Haibing Xiao
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling, Shanxi, 712100, PR China
| | - Hassan Bashir
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
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Sedimentary Record of Polycyclic Aromatic Hydrocarbons from the Shuanglong Catchment, Southwest China. J CHEM-NY 2017. [DOI: 10.1155/2017/4976574] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) in the dated sediments from the Shuanglong catchment in the southwest of China were measured to characterize source inputs. The PAHs concentrations in the priority controlling list of US EPA (∑PAHs) ranged within 102.47~563.24 ng g−1, with an average value of 207.18 ng g−1. The 2-3 rings PAHs were predominant, accounting for 73.77% of ∑PAH. According to the classification of pollution levels, ∑PAHs concentrations in the sediments are within the range of moderate pollution level. Both the total and individual PAH concentrations changed with the depth. The profile distribution of PAHs concentration in the sediments suggested that PAHs acted as an effective way to reconstruct the historical trends of socioeconomic changes in the study areas. Results of Ant/(Ant + Phe), Fla/(Fla + Pyr), and BaA/(BaA + Chry) show that petroleum and petrogenic matter are attributed to the potential pollution source in the Shuanglong catchment. The coal combustion and incomplete combustion of gasoline and fossil fuel are dominant. TOC contents had positive correlation with ∑PAHs (R2=0.72, P<0.001), 2-3 rings (R2=0.44, P<0.001), 4-ring (R2=0.78, P<0.001), and 5-6 rings (R2=0.62, P<0.001).
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Xu M, Wang Y, Yang H, Xie B, Niu X. Modern climate and vegetation variability recorded in organic compounds and carbon isotopic compositions in the Dianchi watershed. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:14314-14324. [PMID: 25976326 DOI: 10.1007/s11356-015-4651-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 05/04/2015] [Indexed: 06/04/2023]
Abstract
The aliphatic hydrocarbons distribution and compound-specific characteristics of carbon isotopic compositions in the sediments from the small catchment (197 km(2)) of the Dianchi watershed were investigated for identification of modern climate and vegetation variations in the study area. Results show that a regular bimodal n-alkanes distribution ranged from nC16 to nC33, with strong dominance at nC17 for short-chain n-alkanes and nC31 for long-chain n-alkanes. Mass chromatogram of total fatty acids also indicates corresponding mixed contribution of algae, hydrophilous non-emergent (C4 plants) and terrestrial plants (C3 plants) to sedimentary organic matter (OM). At the depth of -24 to -25 cm (early 1970s), nC31/nC17 and terrestrial to aquatic ratio of hydrocarbons (TAR) values decrease, suggesting a shift of OM origins from C3 terrestrial plants to algae-derived C4 plants. The highest water stage in 1971 was found to be recorded in the particle size (<4 μm). For long-chain alkanes, the values of δ (13)Corg and δ (13)Cn-alkanes varied from -26.9 to -22.4 and -33.4 to -27.9 ‰, respectively. Population growth and economic development led to a demand for abundant habitable and cultivable land. Due to unreasonable land expansion, the primordial forest sporadically distributed. A mixture of C3 and C4 plants probably replaced C3 plants as the sources of OM in the past 10 years. The changes of land-use types and severe drought resulted in the excessive OM inputs to the watershed.
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Affiliation(s)
- Meina Xu
- School of Geography Science, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing, 210023, China
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Cooper RJ, Pedentchouk N, Hiscock KM, Disdle P, Krueger T, Rawlins BG. Apportioning sources of organic matter in streambed sediments: an integrated molecular and compound-specific stable isotope approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 520:187-197. [PMID: 25817221 DOI: 10.1016/j.scitotenv.2015.03.058] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 03/14/2015] [Accepted: 03/15/2015] [Indexed: 06/04/2023]
Abstract
We present a novel application for quantitatively apportioning sources of organic matter in streambed sediments via a coupled molecular and compound-specific isotope analysis (CSIA) of long-chain leaf wax n-alkane biomarkers using a Bayesian mixing model. Leaf wax extracts of 13 plant species were collected from across two environments (aquatic and terrestrial) and four plant functional types (trees, herbaceous perennials, and C3 and C4 graminoids) from the agricultural River Wensum catchment, UK. Seven isotopic (δ13C27, δ13C29, δ13C31, δ13C27-31, δ2H27, δ2H29, and δ2H27-29) and two n-alkane ratio (average chain length (ACL), carbon preference index (CPI)) fingerprints were derived, which successfully differentiated 93% of individual plant specimens by plant functional type. The δ2H values were the strongest discriminators of plants originating from different functional groups, with trees (δ2H27-29=-208‰ to -164‰) and C3 graminoids (δ2H27-29=-259‰ to -221‰) providing the largest contrasts. The δ13C values provided strong discrimination between C3 (δ13C27-31=-37.5‰ to -33.8‰) and C4 (δ13C27-31=-23.5‰ to -23.1‰) plants, but neither δ13C nor δ2H values could uniquely differentiate aquatic and terrestrial species, emphasizing a stronger plant physiological/biochemical rather than environmental control over isotopic differences. ACL and CPI complemented isotopic discrimination, with significantly longer chain lengths recorded for trees and terrestrial plants compared with herbaceous perennials and aquatic species, respectively. Application of a comprehensive Bayesian mixing model for 18 streambed sediments collected between September 2013 and March 2014 revealed considerable temporal variability in the apportionment of organic matter sources. Median organic matter contributions ranged from 22% to 52% for trees, 29% to 50% for herbaceous perennials, 17% to 34% for C3 graminoids and 3% to 7% for C4 graminoids. The results presented here clearly demonstrate the effectiveness of an integrated molecular and stable isotope analysis for quantitatively apportioning, with uncertainty, plant-specific organic matter contributions to streambed sediments via a Bayesian mixing model approach.
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Affiliation(s)
- Richard J Cooper
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
| | - Nikolai Pedentchouk
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Kevin M Hiscock
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Paul Disdle
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | | | - Barry G Rawlins
- British Geological Survey, Keyworth, Nottingham NG12 5GG, UK
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