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Qu X, Huang C, Rao Z, Wu L, Luo Y, Chen F, Li Y, Zhao L, Liu L, Song Z, Deng W. Natural and anthropogenic controls on environmental change during the Holocene based on a multi-proxy record obtained from subalpine peatland in southern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169446. [PMID: 38159757 DOI: 10.1016/j.scitotenv.2023.169446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/02/2023] [Accepted: 12/15/2023] [Indexed: 01/03/2024]
Abstract
The interactions between past climate, human activity and environmental change in subtropical mountainous areas are poorly understood due to the lack of reliable records in South China. In this study, the evolution of the East Asian summer monsoon (EASM) during the Holocene, and the interactions between regional human activity and environmental change, were studied using multi-proxy records from a subalpine peat core recovered from South China. The chronology of this peat core has been well-constrained by 10 AMS 14C dates of peat stems. A series of proxy indicators, including carbon isotopes (δ13C), loss on ignition (LOI), magnetic susceptibility (MS), the chemical index of alteration (CIA), and geochemical elements from the Shiwangutian (SWGT) peatland were used to reconstruct the palaeohydrological changes during the Holocene. Regional moisture levels showed a generally arid-wet-arid pattern, and three phases of climatic change were detected as follows. 1) Between 11,600 and 9000 cal yr BP, the EASM was weak and a relatively dry climate developed. 2) Between 9000 and 4000 cal yr BP, the prevalence of humid climatic conditions was associated with a strong summer monsoon. 3) After 4000 cal yr BP, the climate shifted to relatively dry conditions. Further comparisons and analysis suggested that solar insolation, migration of the Intertropical Convergence Zone (ITCZ), and El Niño-Southern Oscillation (ENSO) activity played an important role in determining the variations in Holocene EASM intensity. In addition, the increase in both MS and heavy metal concentrations over the last 1000 years is consistent with an increase in the population of Hunan Province. Therefore, it can be inferred that population growth and the associated expansion of cropland and mining led to an increase in soil erosion and metal tool use. These findings suggest that the impact of human activity generally outweighed the natural climatic controls on the environment and landscape in the mountainous region of southern China over the last 1000 years.
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Affiliation(s)
- Xiaoxu Qu
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, Guangdong 524088, China
| | - Chao Huang
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, Guangdong 524088, China; Key Laboratory of Marine Mineral Resources, Ministry of Natural Resources, Guangzhou Marine Geological Survey, Guangzhou 511458, China; Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Guangdong Ocean University, Zhanjiang 524088, China; Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources, China.
| | - Zhiguo Rao
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographical Sciences, Hunan Normal University, Changsha 410081, China
| | - Liyuan Wu
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, Guangdong 524088, China
| | - Yongyi Luo
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, Guangdong 524088, China
| | - Fajin Chen
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, Guangdong 524088, China; Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Guangdong Ocean University, Zhanjiang 524088, China; Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources, China
| | - YunXia Li
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographical Sciences, Hunan Normal University, Changsha 410081, China
| | - Lin Zhao
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographical Sciences, Hunan Normal University, Changsha 410081, China
| | - Lidan Liu
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographical Sciences, Hunan Normal University, Changsha 410081, China
| | - Zhiguang Song
- College of Chemistry and Environment, Guangdong Ocean University, Zhanjiang 524088, China
| | - Wenfeng Deng
- State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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Liu H, Gu Y, Qin Y, Yu Z, Huang X, Xie S, Zheng M, Zhang Z, Cheng S. The elemental enrichments at Dajiuhu Peatland in the Middle Yangtze Valley in response to changes in East Asian monsoon and human activity since 20,000 cal yr BP. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:143990. [PMID: 33316522 DOI: 10.1016/j.scitotenv.2020.143990] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/30/2020] [Accepted: 11/15/2020] [Indexed: 06/12/2023]
Abstract
Here we present multiproxy inorganic geochemical records from a peat core (ZK5) from the Dajiuhu Basin in central China to investigate peatland deposition processes and atmospheric metal pollution and to explore their relationships with East Asian monsoon change and human activities in the Middle Yangtze Valley since 20,000 cal yr BP. The peat physicochemical data including total organic carbon (TOC), trace elements, and grain-size show that the site has changed from a lake during the cold-wet Last Glacial Maximum (LGM; 20,000-18,000 cal yr BP), to a marshy wetland during the mild last deglaciation (18,000-11,500 cal yr BP) and a peatland during the mostly warm and dry Holocene (11,500 cal yr BP-present). This general sequence corresponds with changes in East Asian monsoon indicated by stalagmites δ18O records and boreal summer insolation. Marked decreases in trace element concentrations correspond to two periods of peatland expansion during the abrupt hydroclimatic transitions from the LGM to the last deglaciation and from the last deglaciation to the early Holocene. Warm-dry mid-Holocene might induce high organic matter decomposition in peat sediments. Increasing natural element concentrations since the late Holocene are correlated with the weakening of the summer monsoon and elevated atmospheric dust deposition. Increasing Cu and Pb concentrations in peat record indicate large-scale Cu smelting during the Bronze Age and excessive coal burning during the 10th century or so. The anthropogenic heavy metals were transported by prevailing East Asian summer monsoon and deposited in the Dajiuhu Basin during periods of heightened human activities. Our compilation of heavy metals records across China confirmed the noticeable impacts of the historical human activity on deposition environments during the late Holocene. Consequently, trace elements from the Dajiuhu Basin are reliable proxies for capturing monsoon climate-induced peatland deposition response and present important evidence for a historical atmospheric heavy metal pollution in the Middle Yangtze Valley. Our results offer useful references for peatland evolution and protection under the background of global change.
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Affiliation(s)
- Hongye Liu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China; Hubei Key Laboratory of Wetland Evolution & Eco-Restoration (WEER), China University of Geosciences, Wuhan 430074, China
| | - Yansheng Gu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China; Hubei Key Laboratory of Wetland Evolution & Eco-Restoration (WEER), China University of Geosciences, Wuhan 430074, China.
| | - Yangmin Qin
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China; Hubei Key Laboratory of Wetland Evolution & Eco-Restoration (WEER), China University of Geosciences, Wuhan 430074, China
| | - Zicheng Yu
- Department of Earth and Environmental Sciences, Lehigh University, Bethlehem, PA 18015, USA; Institute for Peat and Mire Research, School of Geographical Sciences, Northeast Normal University, Changchun 130024, China
| | - Xianyu Huang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Shucheng Xie
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Min Zheng
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Zhiqi Zhang
- Hubei Key Laboratory of Wetland Evolution & Eco-Restoration (WEER), China University of Geosciences, Wuhan 430074, China; Shennongjia National Park Administration, Shennongjia 442400, Hubei, China
| | - Shenggao Cheng
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
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Li Y, Ma C, Zhu C, Huang R, Zheng C. Historical anthropogenic contributions to mercury accumulation recorded by a peat core from Dajiuhu montane mire, central China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 216:332-339. [PMID: 27289528 DOI: 10.1016/j.envpol.2016.05.083] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 05/27/2016] [Accepted: 05/29/2016] [Indexed: 06/06/2023]
Abstract
Mercury (Hg) accumulation records spanning the last 16,000 years before present (yr BP, relative to AD 1950) were derived from a peat core collected from Dajiuhu mire, central China. The natural Hg concentration and accumulation rate (free from anthropogenic influence) were 135.5 ± 53.9 ng g(-1) and 6.5 ± 4.5 μg m(-2) yr(-1), respectively. The increase in Hg flux that started from a core depth of 96.5 cm (3358 cal yr BP) is independent of soil erosion and organic matter content. We attribute this to an increase in atmospheric Hg deposition derived from regional anthropogenic activities. Anthropogenic Hg accumulation rates (Hg-ARA) in the pre-industrial period peaked during the Ming and the early Qing dynasties (582-100 cal yr BP), with Hg-ARA of 9.9-24.6 and 10.7-24.4 μg m(-2) yr(-1), respectively. In the industrial interval (post∼1850 AD), Hg-ARA increased progressively and reached 32.7 μg m(-2) yr(-1) at the top of the core. Our results indicate the existence of regional atmospheric Hg pollution spanning the past ∼3400 years, and place recent Hg enrichment in central China in a broader historical context.
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Affiliation(s)
- Yuanping Li
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210046, PR China; School of Resources and Environment, West Anhui University, Lu'an, Anhui 237012, PR China
| | - Chunmei Ma
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210046, PR China.
| | - Cheng Zhu
- School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu 210046, PR China
| | - Run Huang
- School of Resources and Environment, West Anhui University, Lu'an, Anhui 237012, PR China
| | - Chaogui Zheng
- School of Geography Information and Tourism, Chuzhou University, Chuzhou, Anhui 239000, PR China
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Using Peat Records as Natural Archives of Past Atmospheric Metal Deposition. ENVIRONMENTAL CONTAMINANTS 2015. [DOI: 10.1007/978-94-017-9541-8_12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Kempter H, Krachler M, Shotyk W. Atmospheric Pb and Ti accumulation rates from Sphagnum moss: dependence upon plant productivity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:5509-5515. [PMID: 20545344 DOI: 10.1021/es100366d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The accumulation rates of atmospheric Pb and Ti were obtained using the production rates of Sphagnum mosses collected in four ombrotrophic bogs from two regions of southern Germany: Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Surfaces of Sphagnum carpets were marked with plastic mesh and one year later the production of plant matter was harvested. Metal concentrations were determined in acid digests using sector field ICP-MS employing well established analytical procedures. Up to 12 samples (40 x 40 cm) were collected per site, and 6-10 sites were investigated per bog. Variations within a given sampling site were in the range 2.3-4x for Pb concentrations, 1.8-2.5x for Ti concentrations, 3-8.3x for Pb/Ti, 5.6-7.8x for Pb accumulation rates, and 2.3-6.4x for Ti accumulation rates. However, the median values of these parameters for the sites (6-10 per bog) were quite consistent. The mosses from the bogs in NBF exhibited significantly greater productivity (187-202 g m(-2) a(-1)) compared to the OB peat bogs (71-91 g m(-2) a(-1)), and these differences had a pronounced effect on the Pb and Ti accumulation rates. Highly productive mosses showed no indication of a "dilution effect" of Pb or Ti concentrations, suggesting that more productive plants were simply able to accumulate more particles from the air. The median rates of net Pb accumulation by the mosses are in excellent agreement with the fluxes obtained by direct atmospheric measurements at nearby monitoring stations in both regions (EMEP and MAPESI data).
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Affiliation(s)
- H Kempter
- Institute of Earth Sciences, University of Heidelberg, INF 236, D-69120 Heidelberg, Germany
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Farmer JG, Anderson P, Cloy JM, Graham MC, MacKenzie AB, Cook GT. Historical accumulation rates of mercury in four Scottish ombrotrophic peat bogs over the past 2000 years. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 407:5578-88. [PMID: 19646736 DOI: 10.1016/j.scitotenv.2009.06.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/05/2009] [Accepted: 06/16/2009] [Indexed: 05/04/2023]
Abstract
The historical accumulation rates of mercury resulting from atmospheric deposition to four Scottish ombrotrophic peat bogs, Turclossie Moss (northeast Scotland), Flanders Moss (west-central), Red Moss of Balerno (east-central) and Carsegowan Moss (southwest), were determined via analysis of (210)Pb- and (14)C-dated cores up to 2000 years old. Average pre-industrial rates of mercury accumulation of 4.5 and 3.7 microg m(-2) y(-1) were obtained for Flanders Moss (A.D. 1-1800) and Red Moss of Balerno (A.D. 800-1800), respectively. Thereafter, mercury accumulation rates increased to typical maximum values of 51, 61, 77 and 85 microg m(-2) y(-1), recorded at different times possibly reflecting local/regional influences during the first 70 years of the 20th century, at the four sites (TM, FM, RM, CM), before declining to a mean value of 27+/-15 microg m(-2) y(-1) during the late 1990s/early 2000s. Comparison of such trends for mercury with those for lead and arsenic in the cores and also with direct data for the declining UK emissions of these three elements since 1970 suggested that a substantial proportion of the mercury deposited at these sites over the past few decades originated from outwith the UK, with contributions to wet and dry deposition arising from long-range transport of mercury released by sources such as combustion of coal. Confidence in the chronological reliability of these core-derived trends in absolute and relative accumulation of mercury, at least since the 19th century, was provided by the excellent agreement between the corresponding detailed and characteristic temporal trends in the (206)Pb/(207)Pb isotopic ratio of lead in the (210)Pb-dated Turclossie Moss core and those in archival Scottish Sphagnum moss samples of known date of collection. The possibility of some longer-term loss of volatile mercury released from diagenetically altered older peat cannot, however, be excluded by the findings of this study.
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Affiliation(s)
- John G Farmer
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland, UK.
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