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Kuzmenkova N, Golosov V, Ivanov M, Alexandrin M, Korneva I, Grabenko E, Rozhkova A, Bykhalova O. Bottom sediment radioactivity of the six Caucasus lakes located in different altitude zones. Environ Sci Pollut Res Int 2023; 30:50690-50702. [PMID: 36800094 DOI: 10.1007/s11356-023-25838-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 02/06/2023] [Indexed: 02/18/2023]
Abstract
Natural and artificial radioactivity of bottom sediment in the six lakes of the Western and Central Caucasus have been evaluated. It allowed to define the variation of sedimentation rate during the last 100-150 years using technogenic (137Cs) and natural (210Pb, 226Ra) radionuclides as a chronomarkers. The studied lakes are located in the contrasting geographic conditions, different orographic positions, and have different origin. The average annual precipitation in the area of each of the lakes has been detected to stay relatively constant during the 137Cs fallout period, while the air temperature has markedly increased during the last decades. The detected sedimentation rates are the indirect indicator of climate change in the mountains. They are slightly decreasing owing to the increased protection of soil by vegetation cover in the lower altitude zone; in the upper zones, they are growing due to accelerated glacier retreat. The radioecological situation is estimated as normal. High levels of 137Cs (33 kBq m-2) and 241Am (0.1 kBq m-2) in bottom sediments are attributed to the region-specific geographical characteristics.
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Affiliation(s)
- Natalia Kuzmenkova
- Institute of Geography RAS, Moscow, Russia. .,Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russia.
| | - Valentin Golosov
- Institute of Geography RAS, Moscow, Russia.,Faculty of Geography, Lomonosov Moscow State University, Moscow, Russia.,Department of Landscape Ecology, Institute of Ecology and Environment, Kazan Federal University, Kazan, Russia
| | - Maxim Ivanov
- Institute of Geography RAS, Moscow, Russia.,Faculty of Geography, Lomonosov Moscow State University, Moscow, Russia
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Paradis S, Lo Iacono C, Masqué P, Puig P, Palanques A, Russo T. Evidence of large increases in sedimentation rates due to fish trawling in submarine canyons of the Gulf of Palermo (SW Mediterranean). Mar Pollut Bull 2021; 172:112861. [PMID: 34523427 DOI: 10.1016/j.marpolbul.2021.112861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 08/10/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
Bottom trawling in submarine canyons can affect their natural sedimentation rates, but studies addressing this issue are still scarce. In the Gulf of Palermo (SW Mediterranean), bottom trawling occurs on the slope around Oreto, Arenella and Eleuterio canyons. Analyses of excess 210Pb concentrations and grain size fractions in sediment cores from their canyon axes revealed that sedimentation rates and silt contents increased in all canyons in the 1980s, due to the expansion of more powerful trawlers (>500 HP) to deeper fishing grounds. In Eleuterio and Arenella canyons, sedimentation rates increased by an order of magnitude (0.1-1.4 cm·yr-1), whereas they increased less (0.1-0.7 cm·yr-1) in Oreto Canyon, since the enhanced trawling-derived sediment fluxes into this canyon are affected by sediment resuspension from trawling along its axis. Considering the global expansion of bottom trawling, we anticipate similar alterations in other trawled canyons, with ecological consequences that should be addressed by management strategies.
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Affiliation(s)
- Sarah Paradis
- Institute of Environmental Science and Technology (ICTA) and Physics Department, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain; Geological Institute, Department of Earth Sciences, ETH Zürich, 8092 Zürich, Switzerland.
| | - Claudio Lo Iacono
- Marine Sciences Institute, Consejo Superior de Investigaciones Científicas, Barcelona 08003, Spain
| | - Pere Masqué
- Institute of Environmental Science and Technology (ICTA) and Physics Department, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain; School of Natural Sciences, Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA 6027, Australia; International Atomic Energy Agency, 4a Quai Antoine 1er, 98000 Principality of Monaco, Monaco
| | - Pere Puig
- Marine Sciences Institute, Consejo Superior de Investigaciones Científicas, Barcelona 08003, Spain
| | - Albert Palanques
- Marine Sciences Institute, Consejo Superior de Investigaciones Científicas, Barcelona 08003, Spain
| | - Tommaso Russo
- Laboratory of Experimental Ecology and Aquaculture, Department of Biology, University of Rome Tor Vergata, Rome 00133, Italy
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Guo J, Costa OS, Wang Y, Lin W, Wang S, Zhang B, Cui Y, Fu H, Zhang L. Accumulation rates and chronologies from depth profiles of 210Pb ex and 137Cs in sediments of northern Beibu Gulf, South China sea. J Environ Radioact 2020; 213:106136. [PMID: 31983445 DOI: 10.1016/j.jenvrad.2019.106136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 09/28/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
Beibu Gulf is a highly dynamic and complex coastal environment that is currently experiencing one of the largest rates of development and urbanization in west China. Little is known about the effects of this increased human activity on coastal sedimentation processes and on the rates of sediment accumulation and the variation of organic materials to the coast. In this study, four sediment cores were collected and applied the 210Pb dating method to reconstruct sedimentation rates and historical changes of materials to the northern Beibu Gulf over the past century. Depth profiles of excess 210Pb (210Pbex) showed highest activity values at the surface (28.4-104.0 Bq kg-1) followed by a linear or exponential decay with depth for all but one study site. 137Cs activity ranged between 0.236 and 2.034 Bq kg-1, and a distinct peak activity - representing the 1963 fallout maximum - was observed at all but one site. Sediment chronologies were determined using the Constant Rate of Supply (CRS) model. Calculated accumulation rates in the studied sites were the lowest in the late 1920s and early 1930s (mass accumulation rate (MAR): 0.06 ± 0.01 g cm-2 y-1; sediment accumulation rate (SAR): 0.08 ± 0.01 cm y-1) and increased gradually until reaching maximum values in the 2010s (MAR: 0.22 ± 0.09 g cm-2 y-1; SAR: 0.46 ± 0.32 cm y-1). Current accumulation rates are up to 800% higher than rates observed in the 1920s, with most of the increase happening after 1970, coinciding with the increasing rate of urbanization and development in the region. The highest increase in SAR over the last century (+877%) was observed in Sanniang Bay, with the lowest rate of increase (+283%) observed in Lianzhou Bay. TOC content in these sediments has also increased over the last 100 years. Current values (0.98-1.28%) are about 170% higher than historical concentrations (before 1970). The positive correlations between TOC and population density and GDP growth in major cities surrounding the gulf, provide further indication that human activities have significantly altered the sedimentary environment in recent decades along the northern Beibu Gulf coast.
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Affiliation(s)
- Jing Guo
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China; College of Civil Engineering and Architecture, Guangxi University, Nanning, 530004, China; School of Earth Sciences, The Ohio State University at Mansfield, Mansfield, OH, 44906, USA
| | - Ozeas S Costa
- School of Earth Sciences, The Ohio State University at Mansfield, Mansfield, OH, 44906, USA
| | - Yinghui Wang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China.
| | - Wuhui Lin
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Shaopeng Wang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Bo Zhang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Yefeng Cui
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Hao Fu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China
| | - Linlin Zhang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning, 530004, China; School of Marine Sciences, Guangxi University, Nanning, 530004, China
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Begy RC, Simon H, Kelemen S, Preoteasa L. Investigation of sedimentation rates and sediment dynamics in Danube Delta lake system (Romania) by 210Pb dating method. J Environ Radioact 2018; 192:95-104. [PMID: 29909226 DOI: 10.1016/j.jenvrad.2018.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 06/09/2018] [Accepted: 06/09/2018] [Indexed: 06/08/2023]
Abstract
Being a dynamic environment associated with complex costal, fluvial and marine processes, only a few studies regarding the evolution of the Danube Delta and the human impacts on its ecosystem have been carried out. Being a sensible to all processes occurring in its catchment area, information is stored in the deposited sediments, which can be used as tracers for natural and anthropogenic processes. The aim of this study is to determine a detailed reconstruction of the sedimentation rates in the last century by applying the 210Pb dating method validated by 137Cs profiles. Additionally, the impacts of the construction of river-regulating structures (mainly the Iron Gates Hydro-Energetic Power Plants) are investigated, along with the assessment of natural phenomena (floods, storms etc.). To achieve this, 26 sediment cores from seven lakes were collected. 210Pbsup and 137Cs were determined using gamma spectrometry, while 210Pbtot was measured via alpha spectrometry (210Po), using the CRS model for age determination. From the assessed lakes, the most affected was the Matița Lake with a maximum sedimentation rate of 10.93 g cm-2 yr-1 and the least affected was the Isac Lake. Average sedimentation rates are: 0.95 g cm-2 yr-1 for Cruhlig Lake, 0.70 g cm-2 yr-1 for Uzlina Lake, 0.44 g cm-2 yr-1 for Isac Lake, 0.47 g cm-2 yr-1 for Cuibida Lake, 0.51 g cm-2 yr-1 for Iacob Lake, 1.00 g cm-2 yr-1 for Matița Lake and 0.76 g cm-2 yr-1 for Merhei Lake. Physical parameters (water content, porosity and bulk density) and LOI (organic matter and inorganic carbon content) were determined for each core to differentiate organic and non-organic sedimentation. Beside the natural influences, it is difficult to track the effects of the Iron Gates and not all analysed lakes were suitable for this task. The 1940-1970 period and the following ten years were compared in means of sedimentation: a decrease in sedimentation can be observed in four of the lakes: 59% in Cruhlig Lake, 16% in Uzlina Lake, 10% in Iacob Lake and 42% in Isac Lake, leading to an average 32% for the four lakes. The other three lakes show increasing tendencies of 39% in this period: 87% in Matița Lake, 6% in Merhei Lake and 24% in Cuibida Lake. Sedimentation rates show growths of 3 times after 1989, the most affected being the two northern lakes (3 times increase in both Matița Lake and Merhei Lake) and the four central lakes (2 times in case of Cuibida Lake, 3 times in Iacob Lake, 3 times in Isac Lake and 4 times in Uzlina Lake) with an average increase of 3 times, while the southern one (Cruhlig Lake) 2 times.
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Affiliation(s)
- R-Cs Begy
- Babeș-Bolyai University, Faculty of Environmental Science and Engineering, Fântânele 30, 400294, Cluj-Napoca, Romania; Babeș-Bolyai University, Interdisciplinary Research Institute on Bio-Nano-Science, Treboniu Laurean 42, 400271, Cluj-Napoca, Romania
| | - H Simon
- Babeș-Bolyai University, Faculty of Environmental Science and Engineering, Fântânele 30, 400294, Cluj-Napoca, Romania.
| | - Sz Kelemen
- Babeș-Bolyai University, Faculty of Environmental Science and Engineering, Fântânele 30, 400294, Cluj-Napoca, Romania
| | - L Preoteasa
- University of Bucharest, Faculty of Geography, M. Kogălniceanu Blvd 36-46, Sector 5, 050107, Bucharest, Romania
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Varley A, Tyler A, Bondar Y, Hosseini A, Zabrotski V, Dowdall M. Reconstructing the deposition environment and long-term fate of Chernobyl 137Cs at the floodplain scale through mobile gamma spectrometry. Environ Pollut 2018; 240:191-199. [PMID: 29738947 DOI: 10.1016/j.envpol.2018.04.112] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/20/2018] [Accepted: 04/24/2018] [Indexed: 06/08/2023]
Abstract
Cs-137 is considered to be the most significant anthropogenic contributor to human dose and presents a particularly difficult remediation challenge after a dispersal following nuclear incident. The Chernobyl Nuclear Power Plant meltdown in April 1986 represents the largest nuclear accident in history and released over 80 PBq of 137Cs into the environment. As a result, much of the land in close proximity to Chernobyl, which includes the Polessie State Radioecology Reserve in Belarus, remains highly contaminated with 137Cs to such an extent they remain uninhabitable. Whilst there is a broad scale understanding of the depositional patterns within and beyond the exclusion zone, detailed mapping of the distribution is often limited. New developments in mobile gamma spectrometry provide the opportunity to map the fallout of 137Cs and begin to reconstruct the depositional environment and the long-term behaviour of 137Cs in the environment. Here, full gamma spectrum analysis using algorithms based on the peak-valley ratio derived from Monte Carlo simulations are used to estimate the total 137Cs deposition and its depth distribution in the soil. The results revealed a pattern of 137Cs distribution consistent with the deposition occurring at a time of flooding, which is validated by review of satellite imagery acquired at similar times of the year. The results were also consistent with systematic burial of the fallout 137Cs by annual flooding events. These results were validated by sediment cores collected along a transect across the flood plain. The true merit of the approach was confirmed by exposing new insights into the spatial distribution and long term fate of 137Cs across the floodplain. Such systematic patterns of behaviour are likely to be fundamental to the understanding of the radioecological behaviour of 137Cs whilst also providing a tracer for quantifying the ecological controls on sediment movement and deposition at a landscape scale.
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Affiliation(s)
- Adam Varley
- Department of Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, United Kingdom.
| | - Andrew Tyler
- Department of Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, United Kingdom
| | - Yuri Bondar
- Norwegian Radiation Protection Authority, Grini Næringspark 13, 1332 Østerås, Norway
| | - Ali Hosseini
- Polessie State Radiation-Ecological Reserve, Tereshkovoy Street 7, Khoiniki, Gomel Region, Belarus
| | - Viachaslau Zabrotski
- Norwegian Radiation Protection Authority, Grini Næringspark 13, 1332 Østerås, Norway
| | - Mark Dowdall
- Polessie State Radiation-Ecological Reserve, Tereshkovoy Street 7, Khoiniki, Gomel Region, Belarus
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Yeager KM, Schwehr KA, Schindler KJ, Santschi PH. Sediment accumulation and mixing in the Penobscot River and estuary, Maine. Sci Total Environ 2018; 635:228-239. [PMID: 29674257 DOI: 10.1016/j.scitotenv.2018.04.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 03/26/2018] [Accepted: 04/03/2018] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) was discharged in the late 1960s into the Penobscot River by the Holtra-Chem chlor-alkali production facility, which was in operation from 1967 to 2000. To assess the transport and distribution of total Hg, and recovery of the river and estuary system from Hg pollution, physical and radiochemical data were assembled from sediment cores collected from 58 of 72 coring stations sampled in 2009. These stations were located throughout the lower Penobscot River, and included four principal study regions, the Penobscot River (PBR), Mendall Marsh (MM), the Orland River (OR), and the Penobscot estuary (ES). To provide the geochronology required to evaluate sedimentary total Hg profiles, 58 of 72 sediment cores were dated using the atmospheric radionuclide tracers 137Cs, 210Pb, and 239,240Pu. Sediment cores were assessed for depths of mixing, and for the determination of sediment accumulation rates using both geochemical (total Hg) and radiochemical data. At most stations, evidence for significant vertical mixing, derived from profiles of 7Be (where possible) and porosity, was restricted to the upper ~1-3cm. Thus, historic profiles of both total Hg and radionuclides were only minimally distorted, allowing a reconstruction of their depositional history. The pulse input tracers 137Cs and 239,240Pu used to assess sediment accumulation rates agreed well, while the steady state tracer 210Pb exhibited weaker agreement, likely due to irregular lateral sediment inputs.
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Affiliation(s)
- K M Yeager
- Sedimentary and Environmental Radiochemistry Research Laboratory (SER(2)L), Department of Earth and Environmental Sciences, University of Kentucky, Lexington, KY 40506, United States.
| | - K A Schwehr
- Laboratory for Oceanographic and Environmental Research (LOER), Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77554, United States.
| | - K J Schindler
- Sedimentary and Environmental Radiochemistry Research Laboratory (SER(2)L), Department of Earth and Environmental Sciences, University of Kentucky, Lexington, KY 40506, United States
| | - P H Santschi
- Laboratory for Oceanographic and Environmental Research (LOER), Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77554, United States.
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Andrade RLB, Hatje V, Masqué P, Zurbrick CM, Boyle EA, Santos WPC. Chronology of anthropogenic impacts reconstructed from sediment records of trace metals and Pb isotopes in Todos os Santos Bay (NE Brazil). Mar Pollut Bull 2017; 125:459-471. [PMID: 28800910 DOI: 10.1016/j.marpolbul.2017.07.053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 06/19/2017] [Accepted: 07/22/2017] [Indexed: 05/13/2023]
Abstract
The evolution of the impacts of anthropogenic activities in Todos os Santos Bay was evaluated by profiles of trace metals and Pb isotopes determined in sediment cores. Fluxes of metals increased up to 12, 4 and 2 times for Cu, Pb, and Zn, respectively, compared to those recorded in the beginning of the 20th century. Stable Pb isotopes identified a decommissioned lead smelter and burning of fossil fuels as the main sources of Pb. Most metals showed minor to moderate enrichment factors (EF<4), but Cu and Pb were highly enriched (EF=28 and 6, respectively) at the Aratu harbor. Temporal changes in sediments were associated to different activities, namely Pb smelting, burning of fossil fuels, maritime traffic, petroleum related activities, inputs of domestic effluents, and changes in land uses. The effects of the implementation of environmental policies to improve the waters of the bay could not be identified in the evaluated cores.
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Affiliation(s)
- R L B Andrade
- Centro Interdisciplinar de Energia e Ambiente (CIENAM), Instituto de Química, Universidade Federal da Bahia, Rua Barão de Jeremoabo, s/n, Ondina, Salvador, BA 40170-290, Brazil.
| | - V Hatje
- Centro Interdisciplinar de Energia e Ambiente (CIENAM), Instituto de Química, Universidade Federal da Bahia, Rua Barão de Jeremoabo, s/n, Ondina, Salvador, BA 40170-290, Brazil
| | - P Masqué
- Centre for Marine Ecosystems Research, School of Science, Edith Cowan University, Joondalup, WA 6027, Australia; Institut de Ciència i Tecnologia Ambientals, Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Oceans Institute & School of Physics, The University of Western Australia, Crawley, WA 6009, Australia
| | - C M Zurbrick
- Earth, Atmospheric, and Planetary Sciences (EAPS), Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - E A Boyle
- Earth, Atmospheric, and Planetary Sciences (EAPS), Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - W P C Santos
- Departamento de Química (DAQ-SSA), Instituto Federal da Bahia, Salvador, BA 40301-015, Brazil
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Matisoff G, Watson SB, Guo J, Duewiger A, Steely R. Sediment and nutrient distribution and resuspension in Lake Winnipeg. Sci Total Environ 2017; 575:173-186. [PMID: 27741453 DOI: 10.1016/j.scitotenv.2016.09.227] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/30/2016] [Accepted: 09/30/2016] [Indexed: 06/06/2023]
Abstract
Severe algal blooms in Lake Winnipeg since the late 1990s have been attributed to increased watershed nutrient loading, much of which is associated with suspended particles. Within-lake transport and fate of this nutrient fraction and the importance of internal loading via resuspension, however, are unknown. We measured radioisotopes (7Be, 210Pb, 137Cs), metal and nutrient contents of suspended solids in major tributaries and lake-water, in sediment traps and in bottom sediments to estimate sediment resuspension and mass accumulation rates using two models. Sedimentation rates calculated from 137Cs and 210Pb dated cores and sediment traps indicated that most (95-99%) suspended material is derived from bottom sediment; mixing models using7Be/210Pb and 137Cs yielded similarly high estimates (82 and 84%, respectively). 137Cs profiles in cores indicated that up to ~7cm remains actively resuspended for times up to 23years before incorporation into deeper sediments. Total and bioavailable phosphorus (TP, BAP) in this top sediment layer were generally lower in the North than the South Basin, likely reflecting inputs from the Assiniboine and Red Rivers at the southern end of Lake Winnipeg, with an average of ~30% TP as BAP. Estimates of average sediment-associated internal TP loading for the South Basin (0.264g/m2/y) were ~2× those for the North Basin (0.146g/m2/y). Together, this internal loading is comparable to the magnitude of the external loading. Our results indicate that surficial sediments in Lake Winnipeg will remain a significant and active source of internal nutrient loading for several decades, a process which may delay the response of the lake to external nutrient management.
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Affiliation(s)
- Gerald Matisoff
- Dept. Earth, Environmental and Planetary Sciences, Case Western Reserve University, Cleveland, OH 44106-7216, USA.
| | - Sue B Watson
- Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, Burlington, ON, L7R 4A6, Canada
| | - Jay Guo
- Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, Burlington, ON, L7R 4A6, Canada
| | - Anna Duewiger
- Dept. Earth, Environmental and Planetary Sciences, Case Western Reserve University, Cleveland, OH 44106-7216, USA
| | - Rebecca Steely
- Dept. Earth, Environmental and Planetary Sciences, Case Western Reserve University, Cleveland, OH 44106-7216, USA
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Porto P, Walling DE, Cogliandro V, Callegari G. Exploring the potential for using 210Pb ex measurements within a re-sampling approach to document recent changes in soil redistribution rates within a small catchment in southern Italy. J Environ Radioact 2016; 164:158-168. [PMID: 27474835 DOI: 10.1016/j.jenvrad.2016.06.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 05/21/2016] [Accepted: 06/29/2016] [Indexed: 06/06/2023]
Abstract
In recent years, the fallout radionuclides caesium-137 (137Cs) and unsupported lead-210 (210Pbex) have been successfully used to document rates of soil erosion in many areas of the world, as an alternative to conventional measurements. By virtue of their different half-lives, these two radionuclides are capable of providing information related to different time windows. 137Cs measurements are commonly used to generate information on mean annual erosion rates over the past ca. 50-60 years, whereas 210Pbex measurements are able to provide information relating to a longer period of up to ca. 100 years. However, the time-integrated nature of the estimates of soil redistribution provided by 137Cs and 210Pbex measurements can be seen as a limitation, particularly when viewed in the context of global change and interest in the response of soil redistribution rates to contemporary climate change and land use change. Re-sampling techniques used with these two fallout radionuclides potentially provide a basis for providing information on recent changes in soil redistribution rates. By virtue of the effectively continuous fallout input, of 210Pb, the response of the 210Pbex inventory of a soil profile to changing soil redistribution rates and thus its potential for use with the re-sampling approach differs from that of 137Cs. Its greater sensitivity to recent changes in soil redistribution rates suggests that 210Pbex may have advantages over 137Cs for use in the re-sampling approach. The potential for using 210Pbex measurements in re-sampling studies is explored further in this contribution. Attention focuses on a small (1.38 ha) forested catchment in southern Italy. The catchment was originally sampled for 210Pbex measurements in 2001 and equivalent samples were collected from points very close to the original sampling points again in 2013. This made it possible to compare the estimates of mean annual erosion related to two different time windows. This comparison suggests that mean annual rates of net soil loss had increased during the period between the two sampling campaigns and that this increase was associated with a shift to an increased sediment delivery ratio. This change was consistent with independent information on likely changes in the sediment response of the study catchment provided by the available records of annual sediment yield and changes in the annual rainfall documented for the local area.
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Affiliation(s)
- Paolo Porto
- Dipartimento di Agraria, Università degli Studi Mediterranea, Località Feo di Vito, Reggio Calabria, Italy; Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Rennes Drive, Exeter EX4 4RJ, UK.
| | - Desmond E Walling
- Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Rennes Drive, Exeter EX4 4RJ, UK
| | - Vanessa Cogliandro
- Dipartimento di Agraria, Università degli Studi Mediterranea, Località Feo di Vito, Reggio Calabria, Italy; Dipartimento DIBAF, Università della Tuscia, Viterbo, Italy
| | - Giovanni Callegari
- C.N.R.-Istituto per i Sistemi Agricoli e Forestali del Mediterraneo, Sezione Ecologia e Idrologia Forestale, Rende, CS, Italy
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Bonotto DM, Vergotti M. (210)Pb and compositional data of sediments from Rondonian lakes, Madeira River basin, Brazil. Appl Radiat Isot 2015; 99:5-19. [PMID: 25699663 DOI: 10.1016/j.apradiso.2015.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 01/07/2015] [Accepted: 02/03/2015] [Indexed: 11/28/2022]
Abstract
Gold exploration has been intensive in Brazilian Amazon over the last 40 years, where the use of mercury as an amalgam has caused abnormal Hg concentrations in water bodies. Special attention has been directed to Madeira River due to fact it is a major tributary of Amazon River and that since 1986, gold exploration has been officially permitted along a 350km sector of the river. The (21)(0)Pb method has been used to date sediments taken from nine lakes situated in Madeira River basin, Rondônia State, and to verify where anthropogenic Hg might exist due to gold exploitation in Madeira River. Activity profiles of excess (21)(0)Pb determined in the sediment cores provided a means to evaluate the sedimentation rates using a Constant Flux: Constant Sedimentation (CF:CS) and Constant Rate of Supply (CRS) of unsupported/excess (21)(0)Pb models. A significant relationship was found between the CF:CS sedimentation rates and the mean values of the CRS sedimentation rates (Pearson correlation coefficient r=0.59). Chemical data were also determined in the sediments for identifying possible relationships with Hg occurring in the area. Significant values were found in statistical correlation tests realized among the Hg, major oxides and Total Organic Carbon (TOC) content in the sediments. The TOC increased in the sediment cores accompanied by a loss on ignition (LOI) increment, whereas silica decreased following a specific surface area raising associated to the TOC increase. The CRS model always provided ages within the permitted range of the (21)(0)Pb-method in the studied lakes, whereas the CF:CS model predicted two values above 140 years.
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Affiliation(s)
- Daniel Marcos Bonotto
- Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), Câmpus de Rio Claro, Av. 24-A No.1515, C.P. 178, CEP 13506-900 Rio Claro, São Paulo, Brasil.
| | - Marcelo Vergotti
- Fundação Universidade Federal de Rondônia (UNIR), Av. Presidente Dutra No. 2965, CEP 78900-500 Porto Velho, Rondônia, Brasil.
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