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1. A Megathrust earthquake as source of a Pre-Colombian tsunami in Lesser Antilles: Insight from sediment deposits and tsunami modeling

Author:
L. Cordrie; N. Feuillet; A. Gailler; M. Biguenet; E. Chaumillon; P. Sabatier
Source:
Earth-science reviews 2022 v.228 pp. 104018
ISSN:
0012-8252
Subject:
Japan; altitude; earthquakes; geodesy; historical records; sediments; shrublands; subduction; tectonics; tsunamis; Antigua and Barbuda; Caribbean; Indonesia; Puerto Rico
Abstract:
... No megathrust earthquake similar to the Magnitude class 9 events in Sumatra in 2004 or in Japan in 2011 was firmly reported at the Lesser Antilles subduction zone. The largest known tsunamis followed either a strong intraplate earthquake (1867, Virgin Islands) or were transoceanic due to the 1755 Lisbon earthquake. In this region, where the convergence rate between the American and Caribbean plate ...
DOI:
10.1016/j.earscirev.2022.104018

2. A comparative study of riverine 137Cs dynamics during high-flow events at three contaminated river catchments in Fukushima

Author:
Takuya Niida; Yoshifumi Wakiyama; Hyoe Takata; Keisuke Taniguchi; Honoka Kurosawa; Kazuki Fujita; Alexei Konoplev
Source:
Science of the total environment 2022 v.821 pp. 153408
ISSN:
0048-9697
Subject:
Japan; accidents; cesium radioisotopes; comparative study; environment; inventories; nuclear power; power plants; rain; riparian areas; river water; rivers; seawater; sediments; total suspended solids; watersheds
Abstract:
... This study presents the temporal variations in riverine ¹³⁷Cs concentrations and fluxes to the ocean during high-flow events in three coastal river catchments contaminated by the Fukushima Daiichi Nuclear Power Plant accident. River water samples were collected at points downstream in the Niida, Ukedo, and Takase Rivers during three high-flow events that occurred in 2019–2020. Variations in both t ...
DOI:
10.1016/j.scitotenv.2022.153408

3. A storm-induced flood and associated nearshore dispersal of the river-derived suspended 137Cs

Author:
Yusuke Uchiyama; Natsuki Tokunaga; Kohei Aduma; Yuki Kamidaira; Daisuke Tsumune; Toshiki Iwasaki; Masatoshi Yamada; Yutaka Tadeda; Takashi Ishimaru; Yukari Ito; Yutaka W. Watanabe; Ken Ikehara; Miho Fukuda; Yuichi Onda
Source:
Science of the total environment 2022 v.816 pp. 151573
ISSN:
0048-9697
Subject:
Japan; coasts; earthquakes; freshwater; marine environment; models; nuclear power; power plants; riparian areas; rivers; sediment transport; sediments; typhoons
Abstract:
... Accidental leakage of radionuclides from the Fukushima Nuclear Power Plant (FNPP1) took place in the aftermath of the catastrophic tsunamis associated with the Great East Japan Earthquake that occurred on March 11, 2011. Significant amount of radionuclides released into the atmosphere were reportedly transported and deposited on land located near FNPP1. The Niida River, Fukushima, Japan, has been ...
DOI:
10.1016/j.scitotenv.2021.151573

4. Benthic food web structures as an explanation for prolonged ecological half-life of 137Cs in flatfish species in the Fukushima coastal area

Author:
Isak Holmerin; Filip Svensson; Toru Hirawake; Takashi Ishimaru; Yukari Ito; Jota Kanda; Francisco Nascimento; Clare Bradshaw
Source:
Journal of environmental radioactivity 2022 v.246 pp. 106844
ISSN:
0265-931X
Subject:
Japan; Pleuronectiformes; accidents; benthic organisms; cesium radioisotopes; coasts; demersal fish; digestive system; food webs; half life; nuclear power; pelagic fish; power plants; radioactivity; sediments; stable isotopes
Abstract:
... After the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP), Japan, in March 2011, ¹³⁷Cs in demersal fish had, between 2011 and 2015, a prolonged ecological half-life when compared to pelagic fish. Using stable isotope mixing models combined with gut content analysis and ¹³⁷Cs activity concentrations, this study investigated the hypothesis that an unexplored food web structure could be ...
DOI:
10.1016/j.jenvrad.2022.106844

5. Development of Quantitative Real-Time PCR for Detecting Environmental DNA Derived from Marine Macrophytes and Its Application to a Field Survey in Hiroshima Bay, Japan

Author:
Masami Hamaguchi; Toshihiro Miyajima; Hiromori Shimabukuro; Masakazu Hori
Source:
Water 2022 v.14 no.5 pp. -
ISSN:
2073-4441
Subject:
Japan; Rhodophyta; Sargassum; Ulva; Zostera marina; blue carbon; carbon dioxide; carbon sinks; climate change; coasts; death; ecological function; environmental DNA; marine environment; organic carbon; quantitative polymerase chain reaction; seagrasses; sediments; surveys; water
Abstract:
... The sequestration and storage of carbon dioxide by marine macrophytes is called blue carbon; this ecosystem function of coastal marine ecosystems constitutes an important countermeasure to global climate change. The contribution of marine macrophytes to blue carbon requires a detailed examination of the organic carbon stock released by these macrophytes. Here, we introduce a quantitative real-time ...
DOI:
10.3390/w14050827

6. Development of the East Korea Warm Current in the Hupo Trough of the southwestern East Sea (Japan Sea) since the Last Glacial Maximum based on TEX86 and [formula omitted] paleothermometers

Author:
Yu-Hyeon Park; Boo-Keun Khim
Source:
Organic geochemistry 2022 pp. 104446
ISSN:
0146-6380
Subject:
El Nino; Holocene epoch; Japan; climate; geochemistry; glaciation; monsoon season; observational studies; seawater; sediments; spring; surface water temperature; winter; Korean Peninsula
Abstract:
... In this study, we documented seawater temperatures estimated from U37K' and TEX₈₆ using a sediment core (ES14-GC02) from the Hupo Trough influenced by the East Korea Warm Current (EKWC) and tested the applicability of the TEX₈₆ paleothermometer to reconstruct seawater temperature variability of the EKWC since the Last Glacial Maximum (LGM). Compared to in situ observational data, U37K' temperature ...
DOI:
10.1016/j.orggeochem.2022.104446

7. Effects of temperature and oxygen on 137Cs desorption from bottom sediment of a dam lake

Author:
Hideki Tsuji; Hironori Funaki; Mirai Watanabe; Seiji Hayashi
Source:
Applied geochemistry 2022 v.140 pp. 105303
ISSN:
0883-2927
Subject:
Japan; cesium radioisotopes; desorption; dissolved oxygen; equations; freshwater lakes; geochemistry; organic matter; oxygen; regression analysis; sediments; spatial distribution; summer; surface water; thermodynamics; water temperature
Abstract:
... The temperature and oxygen environment play important roles in the desorption of ¹³⁷Cs from freshwater lake sediment to lake water. In this study, 12 quarterly surveys were performed to measure the dissolved ¹³⁷Cs concentration in surface and bottom lake water, the vertical distribution of water temperature, and the dissolved oxygen (DO) concentration at the upstream, midstream, and downstream sit ...
DOI:
10.1016/j.apgeochem.2022.105303

8. Enhanced understanding of physicochemical constraints on Corbicula japonica habitat in Lake Shinji assisted by machine learning

Author:
Jonathan Derot; Hiroshi Yajima; Mikio Nakamura
Source:
Ecological informatics 2022 v.69 pp. 101608
ISSN:
1574-9541
Subject:
Corbicula japonica; Japan; algorithms; clams; databases; fisheries; habitats; lakes; local government; sediments; silty clay soils; transportation; water quality
Abstract:
... The catch of Corbicula japonica is one of the top three in Japan's inland water fisheries. Most of the Japanese fishing stock of this bivalve comes from Lake Shinji. Since the 1980's the catch of this species declined drastically with strong inter-annual variation. New recruitment and poor growth of the clams were thought to be the main reasons for this decline. This bivalve has a poor transportat ...
DOI:
10.1016/j.ecoinf.2022.101608

9. Evaluation of the baseline carbon sequestration rates of Indo‐Pacific temperate and tropical seagrass meadow sediments

Author:
Toshihiro Miyajima; Masami Hamaguchi; Masakazu Hori
Source:
Ecological research 2022 v.37 no.1 pp. 9-20
ISSN:
0912-3814
Subject:
Japan; United Nations Framework Convention on Climate Change; blue carbon; carbon dioxide; carbon radioisotopes; carbon sequestration; climate; geophysics; greenhouse gases; hydrodynamics; organic carbon; research; sediments; surface area; temporal variation; Thailand
Abstract:
... Seagrass meadows have great capacity to sequester and store organic carbon (OC) in sediments for the long term and have been considered as a carbon dioxide sink for national greenhouse gas inventories in the Intergovernmental Panel on Climate Change Guidelines. Therefore, there is an urgent need to determine a reliable, well‐constrained estimate of the baseline long‐term OC sequestration (burial) ...
DOI:
10.1111/1440-1703.12263

10. How to evaluate sediment fingerprinting source apportionments

Author:
P. V. G. Batista; J. P. Laceby; O. Evrard
Source:
Journal of soils and sediments 2022 v.22 no.4 pp. 1315-1328
ISSN:
1439-0108
Subject:
Bayesian theory; Japan; colorimetry; decision making; model uncertainty; model validation; sediments; soil
Abstract:
... PURPOSE: Evaluating sediment fingerprinting source apportionments with artificial mixtures is crucial for supporting decision-making and advancing modeling approaches. However, artificial mixtures are rarely incorporated into fingerprinting research and guidelines for model testing are currently lacking. Here, we demonstrate how to test source apportionments using laboratory and virtual mixtures b ...
DOI:
10.1007/s11368-022-03157-4

11. Implications of spatial priority areas for hydrological ecosystem services through coupling hydrology model and Zonation model under different economic costs of water utilizations in northernmost of Japan

Author:
Min Fan; Manjiang Shi; Yunfeng Liu; Wen Chen; Yue Deng; Meiling Wang
Source:
Mitigation and adaptation strategies for global change 2022 v.27 no.1 pp. 2
ISSN:
1381-2386
Subject:
Japan; Soil and Water Assessment Tool model; case studies; decision making; economic costs; ecosystem management; ecosystem services; ecosystems; global change; nutrient retention; sediments; socioeconomic development; stakeholders; water yield; watersheds
Abstract:
... Although the importance of addressing economic values of ecosystem services in ecological planning and decision-making is evident, substantial practical challenges still remain. In particular, methods to identify spatial priority areas for the provision of hydrological ecosystem services across watershed need to be developed. Spatial priority areas are those locations which provide high benefits f ...
DOI:
10.1007/s11027-021-09976-z

12. Low nitrous oxide concentration and spatial microbial community transition across an urban river affected by treated sewage

Author:
Yiwen Zhou; Risako Toyoda; Toshikazu Suenaga; Tomo Aoyagi; Tomoyuki Hori; Akihiko Terada
Source:
Water research 2022 v.216 pp. 118276
ISSN:
0043-1354
Subject:
Japan; United Nations Framework Convention on Climate Change; denitrification; denitrifying microorganisms; equations; genes; greenhouse gases; microbial communities; municipal wastewater; nitrates; nitrification; nitrogen; nitrous oxide; regression analysis; research; rivers; sediments; sewage treatment; summer; wastewater treatment; water; winter
Abstract:
... Urban rivers receive used water derived from anthropogenic activities and are a crucial source of the potent greenhouse gas nitrous oxide (N₂O). However, considerable uncertainties still exist regarding the variation and mechanisms of N₂O production in response to the discharge of treated sewage from municipal wastewater treatment plants (WWTPs). This study investigated N₂O concentrations and micr ...
DOI:
10.1016/j.watres.2022.118276

13. Migration processes of radioactive cesium in the Fukushima nearshore area: Impacts of riverine input and resuspension

Author:
Toshiharu Misonou; Takahiro Nakanishi; Tadahiko Tsuruta; Takehiko Shiribiki; Yukihisa Sanada
Source:
Marine pollution bulletin 2022 v.178 pp. 113597
ISSN:
0025-326X
Subject:
Japan; cesium radioisotopes; coasts; marine pollution; mass transfer; regression analysis; riparian areas; rivers; seawater; sediment traps; sediments; turbidity
Abstract:
... It is essential to evaluate secondary migration caused by riverine input and resuspension from seabed sediments to estimate the future distribution of radioactive cesium (¹³⁷Cs) in the coastal area off Fukushima Prefecture. In particular, the inflow from rivers cannot be ignored because most of the ¹³⁷Cs inflow from rivers is deposited on the coast without elute into seawater. Two mooring systems ...
DOI:
10.1016/j.marpolbul.2022.113597

14. Morphology Recovery and Convergence of Topographic Evolution in the Natori River Mouth after the 2011 Tohoku Tsunami

Author:
Nguyen Trong Hiep; Hitoshi Tanaka; Nguyen Xuan Tinh
Source:
Water 2022 v.14 no.5 pp. -
ISSN:
2073-4441
Subject:
Japan; coasts; earthquakes; estuaries; evolution; littoral zone; riparian areas; rivers; sediments; shorelines; topography; tsunamis; water
Abstract:
... The 2011 Great East Japan earthquake and tsunami caused significant damage along the coastal region in Miyagi Prefecture. In the Natori River of Miyagi Prefecture, the recovery process of the estuarine morphology has been observed since the tsunami arrived. In this study, detailed analyses of collected aerial photographs and beach topography in front of the river mouth were conducted to evaluate w ...
DOI:
10.3390/w14050715

15. Pseudodesulfovibrio sediminis sp. nov., a mesophilic and neutrophilic sulfate-reducing bacterium isolated from sediment of a brackish lake

Author:
Ayaka Takahashi; Hisaya Kojima; Miho Watanabe; Manabu Fukui
Source:
Archives of microbiology 2022 v.204 no.6 pp. 307
ISSN:
0302-8933
Subject:
Japan; chromosomes; ethanol; fatty acids; genes; genomics; glucose; lactic acid; lakes; new species; nitrates; nucleotide sequences; pH; phenotype; pyruvic acid; sediments; sulfate-reducing bacteria; sulfates; sulfites; temperature; thiosulfates
Abstract:
... A novel mesophilic and neutrophilic sulfate-reducing bacterium, strain SF6ᵀ, was isolated from sediment of a brackish lake in Japan. Cells of strain SF6ᵀ were motile and rod-shaped with length of 1.2–2.5 μm and width of 0.6–0.9 μm. Growth was observed at 10–37 °C with an optimum growth temperature of 28 °C. The pH range for growth was 5.8–8.2 with an optimum pH of 7.0. The most predominant fatty a ...
DOI:
10.1007/s00203-022-02870-5

16. Radiocaesium accumulation and fluctuating asymmetry in the Japanese mitten crab, Eriocheir japonica, along a gradient of radionuclide contamination at Fukushima

Author:
Neil Fuller; Jim T. Smith; Tsugiko Takase; Alex T. Ford; Toshihiro Wada
Source:
Environmental pollution 2022 v.292 pp. 118479
ISSN:
0269-7491
Subject:
Eriocheir japonica; Japan; accidents; asymmetry; catadromous fish; cesium radioisotopes; freshwater; nuclear power; power plants; radioactive pollution; sediments
Abstract:
... The 2011 Tohoku earthquake-tsunami and the subsequent nuclear accident at the Fukushima Dai-ichi Nuclear Power Station (FDNPS) led to large-scale radionuclide contamination of the marine and freshwater environment. Monitoring studies of marine food products in the Fukushima region have generally demonstrated a declining trend in radiocaesium concentrations. However, the accumulation and eliminatio ...
DOI:
10.1016/j.envpol.2021.118479

17. Radiocesium transfer into freshwater planktonic Chlamydomonas spp. microalgae in a pond near the Fukushima Dai-ichi Nuclear Power Plant

Author:
Yoshito Sasaki; Hironori Funaki; Kenso Fujiwara
Source:
Limnology 2022 v.23 no.1 pp. 1-7
ISSN:
1439-8621
Subject:
Chlamydomonas; Japan; cesium radioisotopes; freshwater; limnology; microalgae; nuclear power; plankton; power plants; sediments; total suspended solids
Abstract:
... We investigated the transfer of radiocesium and its behavior in living cells and cellular debris in a Chlamydomonas spp. bloom in a pond located approximately 5 km from the Fukushima Dai-ichi Nuclear Power Plant. A microalgal bloom in the pond was the dominant factor in determining the radiocesium concentration (Bq/L) of the > 0.45 μm pond water fraction. The water-to-algae transfer factor [(¹³⁷Cs ...
DOI:
10.1007/s10201-021-00674-y

18. Reconstruction of time changes in radiocesium concentrations in the river of the Fukushima Dai-ichi NPP contaminated area based on its depth distribution in dam reservoir's bottom sediments

Author:
Alexei Konoplev; Yoshifumi Wakiyama; Toshihiro Wada; Maxim Ivanov; Mikhail Komissarov; Kenji Nanba
Source:
Environmental research 2022 v.206 pp. 112307
ISSN:
0013-9351
Subject:
Japan; accidents; cesium radioisotopes; models; nuclear power; power plants; remediation; research; rivers; sediments; Ukraine
Abstract:
... Radionuclide depth distribution in bottom sediments in deep-water zones of dam reservoirs, where no sediment mixing occurs, can be used to reconstruct time changes in particulate activity concentrations of radionuclides strongly bound to bottom sediments. This approach was used to analyze the ¹³⁷Cs concentration profile in a bottom sediment core collected from Ogaki dam reservoir on the Ukedo Rive ...
DOI:
10.1016/j.envres.2021.112307

19. Remobilisation of radiocaesium from bottom sediments to water column in reservoirs in Fukushima, Japan

Author:
Hironori Funaki; Hideki Tsuji; Takahiro Nakanishi; Kazuya Yoshimura; Kazuyuki Sakuma; Seiji Hayashi
Source:
Science of the total environment 2022 v.812 pp. 152534
ISSN:
0048-9697
Subject:
Japan; accidents; bioavailability; cesium radioisotopes; freshwater; ion exchange; mountains; nuclear power; power plants; riparian areas; sediments; watersheds
Abstract:
... Reservoir sediments generally act as a sink for radionuclides derived from nuclear accidents, but under anaerobic conditions, several radionuclides remobilise in bioavailable form from sediments to water columns, which may contribute to the long-term contamination of aquatic products. This study systematically investigated the ¹³⁷Cs activities of sediment–pore water, providing a direct evidence of ...
DOI:
10.1016/j.scitotenv.2021.152534

20. Responses of the benthic environment to reduction in anthropogenic nutrient loading in the Seto Inland Sea (Japan), based on M-AMBI assessment

Author:
Akira Umehara; Ángel Borja; Akiyuki Ishida; Satoshi Nakai; Wataru Nishijima
Source:
Marine environmental research 2022 v.173 pp. 105509
ISSN:
0141-1136
Subject:
Japan; advection; benthic ecosystems; benthic zone; chlorophyll; eutrophication; research; sediments; surface water; total organic carbon
Abstract:
... Deterioration of the sediment environment and benthic ecosystem is an undesirable effect of eutrophication, but little is known about the response of macrobenthic communities to eutrophication and their long-term recovery. In the present study, temporal changes in benthic ecological status, associated with reductions in anthropogenic impacts on a largest semi-enclosed sea in Japan, were determined ...
DOI:
10.1016/j.marenvres.2021.105509

21. Spatial distribution and benthic risk assessment of cyclic, linear, and modified methylsiloxanes in sediments from Tokyo Bay catchment basin, Japan: Si-based mass profiles in extractable organosilicon

Author:
Yuichi Horii; Nobutoshi Ohtsuka; Takahiro Nishino; Keisuke Kuroda; Yoshitaka Imaizumi; Takeo Sakurai
Source:
Science of the total environment 2022 pp. 155956
ISSN:
0048-9697
Subject:
Japan; basins; environment; hydrogen; probabilistic risk assessment; sediments; silane; silicone; watersheds
Abstract:
... We investigated the spatial distribution, mass profiles, and benthic risk assessment of a wide range of methylsiloxanes (MSs), including 7 cyclic MSs (CMSs; D3–D9; the number refers to the number of SiO bonds), 13 linear MSs (LMSs; L3–L15), and 15 modified and other MSs (MMSs) in sediments from the Tokyo Bay catchment basin, Japan. We observed widespread distribution of MSs (ΣCMS, ΣLMS, and ΣMMS) ...
DOI:
10.1016/j.scitotenv.2022.155956

22. Suitable indicators to determine tsunami impact on coastal areas in Northern Japan, Aomori Prefecture

Author:
Mike Frenken; Piero Bellanova; Yuichi Nishimura; Philipp Schulte; Frank Lehmkuhl; Klaus Reicherter; Jan Schwarzbauer
Source:
Environmental monitoring and assessment 2022 v.194 no.5 pp. 385
ISSN:
0167-6369
Subject:
Japan; coasts; data collection; pollution; sediments; total organic carbon; tsunamis
Abstract:
... The 2011 Tohoku-oki tsunami released and mobilized many anthropogenic and natural organic compounds and, hereby, left a clear signature in its sedimentary remnants. In this study, a wide variety of organic marker substances were analyzed in 15 sediment profiles from the Aomori coast (Northern Japan). Total organic carbon (TOC) and fine grain fraction normalization have been tested with the wide da ...
DOI:
10.1007/s10661-022-09989-4

23. The importance of the genetic diversity of the HcRNAV ssRNA virus in the viral-based bloom control of the dinoflagellate Heterocapsa circularisquama

Author:
Natsuko Nakayama; Masami Hamaguchi
Source:
Aquaculture 2022 v.546 pp. 737318
ISSN:
0044-8486
Subject:
Heterocapsa circularisquama; Japan; algal blooms; biological control; biological control agents; capsid; coat proteins; cross reaction; genetic variation; haplotypes; mutation rate; natural selection; nucleotide sequences; positive sense, single-stranded RNA viruses; salt lakes; sediments; viral core proteins
Abstract:
... The HcRNAV virus has been used to control the blooms of the harmful dinoflagellate Heterocapsa circularisquama through the spraying of autochthonous sediment containing HcRNAV from prior blooms. When using natural substances for harmful algal bloom (HAB) control, the effects on local ecosystems must be ascertained and minimized. Specifically, HcRNAV is a single-stranded RNA virus which replicates ...
DOI:
10.1016/j.aquaculture.2021.737318

24. Vertical profiles of legacy organochlorine pesticides in sediment cores from lake Nakaumi, Japan

Author:
Heesoo Eun; Yun Seok Kim; Toshihiro Sakamoto; Agata Miecznikowska; Jerzy Falandysz; Shigeki Masunaga; Hidenobu Kunii
Source:
Chemosphere 2022 v.290 pp. 133254
ISSN:
0045-6535
Subject:
DDT (pesticide); HCH (pesticide); Japan; chlordane; chlorinated hydrocarbons; cluster analysis; heptachlor; hexachlorobenzene; lakes; metabolites; mirex; pentachlorophenol; pesticide application; sediments; spatial distribution
Abstract:
... Two sediment core samples from the brackish Lake Nakaumi in Japan were analyzed to determine the historical profiles of organochlorine pesticides (OCPs). It was observed that from the 1940s to 2005, the vertical distribution of OCPs in sediment cores reflected the temporal trend of pesticide usage in Japan. Dichlorodiphenyltrichloroethane (DDT) and its metabolites were predominant, with concentrat ...
DOI:
10.1016/j.chemosphere.2021.133254

25. A modeling study on the oceanic dispersion and sedimentation of radionuclides off the coast of Fukushima

Author:
Yuki Kamidaira; Yusuke Uchiyama; Hideyuki Kawamura; Takuya Kobayashi; Shigeyoshi Otosaka
Source:
Journal of environmental radioactivity 2021 v.238-239 pp. 106724
ISSN:
0265-931X
Subject:
Japan; accidents; adsorption; cesium radioisotopes; clay; coasts; desorption; models; nuclear power; particle size; power plants; radioactivity; seawater; sediments; shear stress
Abstract:
... We developed a three-dimensional prognostic oceanic dispersion model that accounted for the phase transfer of radionuclides between seawater, suspended particles, and seabed sediments with multiscale grain sizes. A detailed hindcast of ¹³⁷Cs in the seabed sediment off the Fukushima coast was conducted to investigate the transfer mechanism of dissolved ¹³⁷Cs derived from the Fukushima Daiichi Nucle ...
DOI:
10.1016/j.jenvrad.2021.106724

26. Additive Effects of Sediment and Nutrient on Leaf Litter Decomposition and Macroinvertebrates in Hyporheic Zone

Author:
Md. Khorshed Alam; Junjiro N. Negishi; Pongpet Pongsivapai; Shohei Yamashita; Tomohiro Nakagawa
Source:
Water 2021 v.13 no.10 pp. -
ISSN:
2073-4441
Subject:
Alnus japonica; Japan; detritivores; hyporheic zone; leaves; macroinvertebrates; nitrates; particle size; plant litter; rivers; sediments; water
Abstract:
... Despite the fact that leaf decomposition constitutes an important function in rivers, how multiple environmental stressors simultaneously affect it remains largely unknown. This study investigated the interactive effects of fine sediments (particle size: <2 mm; experimentally manipulated) and a specific nutrient (i.e., nitrate) on subsurface (hyporheic) leaf litter decomposition rate and macroinve ...
DOI:
10.3390/w13101340

27. Analysis of Stratum Subsidence Induced by Depressurization at an Offshore Hydrate-Bearing Sediment

Author:
Shuxia Li; Shuyue Ding; Didi Wu; Xiaopu Wang; Yongmao Hao; Qingping Li; Weixin Pang
Source:
Energy & fuels 2021 v.35 no.2 pp. 1381-1388
ISSN:
1520-5029
Subject:
Japan; dissociation; energy; permeability; sediments; simulation models; subsidence; temperature; Pacific Ocean
Abstract:
... Gas production from an offshore hydrate-bearing sediment (HBS) by depressurization will reduce the strength of cementation and increase the effective stress of hydrate reservoirs, which can result in some potential geohazards, such as wellbore instability and stratum subsidence. In this study, a thermal–hydrological–mechanical–chemical coupling numerical simulation model was established and applie ...
DOI:
10.1021/acs.energyfuels.0c03833

28. Characteristics and distribution of the event deposits induced by the 2011 Tohoku-oki earthquake and tsunami offshore of Sanriku and Sendai, Japan

Author:
Ken Ikehara; Kazuko Usami; Tomohisa Irino; Akiko Omura; Robert G. Jenkins; Juichiro Ashi
Source:
Sedimentary geology 2021 v.411 pp. 105791
ISSN:
0037-0738
Subject:
earthquakes; sediments; tsunamis; turbidity; Japan
Abstract:
... Deep-sea turbidite deposits are useful tools for submarine paleoseismology. It is fundamental to understand what kind of disturbance occurred owing to the earthquake and which event-induced deposits were formed in a particular area. The 2011 Tohoku-oki earthquake and tsunami were the most destructive geohazards in Japanese history. To understand their influence in the seafloor environment and to c ...
DOI:
10.1016/j.sedgeo.2020.105791

29. Contamination levels and temporal trends of legacy and current-use brominated flame retardants in a dated sediment core from Beppu Bay, southwestern Japan

Author:
Anh Quoc Hoang; Daichi Aono; Isao Watanabe; Michinobu Kuwae; Tatsuya Kunisue; Shin Takahashi
Source:
Chemosphere 2021 v.266 pp. 129180
ISSN:
0045-6535
Subject:
Japan; biphenyl; bromination; decabromodiphenyl ethane; decabromodiphenyl ether; risk; sediments
Abstract:
... Contamination levels and temporal trends of polybrominated diphenyl ethers (PBDEs) and some alternative brominated flame retardants (BFRs) were examined in a dated sediment core from the deepest part of the Beppu Bay, southwestern Japan. PBDEs were found in the upper layers of 0–15 cm depth at concentrations ranging from 5200 to 32,600 pg g⁻¹ with the peak estimated at 1995. Decabromodiphenyl ethe ...
DOI:
10.1016/j.chemosphere.2020.129180

30. Data-driven analysis for source apportionment and geochemical backgrounds establishment of toxic elements and REEs in the Tohoku region, Japan

Author:
Arie Pujiwati; Jiajie Wang; Kengo Nakamura; Yoshishige Kawabe; Noriaki Watanabe; Takeshi Komai
Source:
Chemosphere 2021 v.263 pp. 128268
ISSN:
0045-6535
Subject:
Japan; anthropogenic activities; databases; mineralization; principal component analysis; rare earth elements; rivers; sediments; toxicity
Abstract:
... The Tohoku region of Japan is geologically diverse, with a long agriculture and mining history; however, little information about the origins and distribution mechanisms of elements in this region has been reported. This study aims to provide fundamental insights into the effects of geological features and anthropogenic activities on various elements, including toxic elements and rare-earth elemen ...
DOI:
10.1016/j.chemosphere.2020.128268

31. Determination of brominated flame retardants including polybrominated diphenyl ethers, pentabromoethylbenzene, hexabromobiphenyl, and decabromodiphenyl ethane in sediment samples: Validation of a rapid and efficient clean-up method and application to a sediment core from Lake Biwa, Japan

Author:
Anh Quoc Hoang; Daichi Aono; Ayato Kawashima; Noriaki Hamada; Dede Falahudin; Isao Watanabe; Narumi K. Tsugeki; Michinobu Kuwae; Shin Takahashi
Source:
Chemosphere 2021 v.281 pp. 130867
ISSN:
0045-6535
Subject:
Japan; acid treatment; aluminum oxide; automation; biphenyl; bromination; chromatography; decabromodiphenyl ethane; decabromodiphenyl ether; labor; lakes; purification methods; sediments; silica gel; solvents; sulfuric acid
Abstract:
... The development of rapid and efficient analytical method for the determination of legacy and current-use brominated flame retardants (BFRs) has been performed due to environmental concern related to these pollutants. In the present study, we used an automated clean-up device equipped with pre-packed micro-column sets (containing sulfuric acid impregnated silica gel and silver-modified alumina) to ...
DOI:
10.1016/j.chemosphere.2021.130867

32. Diatom-inferred limnological changes in Lake Inawashiro-ko, Japan, over the past 1700 years

Author:
Kotaro Hirose; Toshikazu Gotoh; Yoshitaka Nagahashi
Source:
Journal of paleolimnology 2021 v.66 no.3 pp. 355-369
ISSN:
0921-2728
Subject:
Aulacoseira; Cyclotella; Fragilaria; Japan; alkalinization; euphotic zone; eutrophication; habitats; lakes; littoral zone; pH; paleoecology; plankton; sediments; water quality
Abstract:
... We inferred paleoenvironmental conditions in Lake Inawashiro-ko, Japan, over the past 1700 years, using diatom assemblages in the uppermost 2 m of sediment core INW2012. The core was characterized by three diatom zones: Zone 3 (302–1556 CE) was dominated by the planktonic taxon Aulacoseira nivalis; Zone 2 (1556–1991 CE) was predominantly planktonic Cyclotella radiosa and Aulacoseira subarctica; Zo ...
DOI:
10.1007/s10933-021-00212-x

33. Distribution and transfer of naturally occurring radionuclides and 137Cs in the freshwater system of the Plitvice Lakes, Croatia, and related dose assessment to wildlife by ERICA Tool

Author:
Božena Skoko; Dinko Babić; Zdenko Franić; Tomislav Bituh; Branko Petrinec
Source:
Environmental science and pollution research international 2021 v.28 no.18 pp. 23547-23564
ISSN:
0944-1344
Subject:
Japan; accidents; cesium radioisotopes; fish; freshwater; lakes; national parks; pollution; radioactivity; radium; research; risk; rivers; sediments; uncertainty; water activity; water distribution; wildlife; Croatia
Abstract:
... The aim of this study was to investigate the natural radioactivity of Plitvice Lakes, under the assumption that due to its status as a National Park, the area can be considered an example of a natural freshwater system. Also, considering the transfer parameter data as the largest source of uncertainty in radiological risk assessments, the impact of site-specific data on dose rate assessment, as op ...
DOI:
10.1007/s11356-021-12415-w

34. Diversity and functions of bacterial communities in water and sediment from the watershed of the Tama River flowing a highly urbanized area

Author:
Nanami Mizusawa; Md. Shaheed Reza; Chiharu Oikawa; Satomi Kuga; Mariko Iijima; Atsushi Kobiyama; Yuichiro Yamada; Yuri Ikeda; Daisuke Ikeda; Kazuho Ikeo; Shigeru Sato; Takehiko Ogata; Toshiaki Kudo; Mitsuru Jimbo; Ko Yasumoto; Naoto Urano; Shugo Watabe
Source:
Fisheries science 2021 v.87 no.5 pp. 697-715
ISSN:
0919-9268
Subject:
Bacteroides; Flavobacterium; Japan; Mycobacterium; Pseudomonas; alpha-Proteobacteria; beta-Proteobacteria; genes; metabolism; metagenomics; river water; rivers; sediments; sulfur; taxonomy; urbanization; virulence; watersheds
Abstract:
... Bacterial communities are important factors governing changes in river ecology. We evaluated the diversity of bacterial communities in sediment and size-fractionated water samples collected from the Tama River, Tokyo, Japan, to verify their taxonomy and functional classes. Samples were collected from three river areas, namely up-, mid- and downstream, and analyzed using MiSeq shotgun metagenomic s ...
DOI:
10.1007/s12562-021-01543-4

35. Evaluation of impacts of bottom fishing on demersal habitats: A case study off the Pacific coast of north-eastern Japan

Author:
Aigo Takeshige; Mai Miyamoto; Yoji Narimatsu; Shiroh Yonezaki; Masashi Kiyota
Source:
Fisheries research 2021 v.238 pp. 105916
ISSN:
0165-7836
Subject:
Japan; biomass; case studies; cluster analysis; coasts; ecosystems; habitats; hardness; research; sediments; species diversity; surveys; sustainable fisheries; topography; trawl nets
Abstract:
... Physical disturbance of the seafloor induced by bottom trawling is of increasing concern from the viewpoints of ecosystem conservation and sustainable fishery. We developed a method for evaluating the impacts of several kinds of trawl gears on the different seafloor habitats using bathymetry and sediment data and scientific survey data off the Pacific coast of north-eastern Japan. Ten types of hab ...
DOI:
10.1016/j.fishres.2021.105916

36. Evaluation of radioiodine (129I) dissolution from sediment of a brackish lake beside a spent nuclear fuel reprocessing plant in Japan

Author:
Yuhi Satoh; Shoko Imai
Source:
Journal of environmental radioactivity 2021 v.233 pp. 106608
ISSN:
0265-931X
Subject:
Japan; absorption; iodine; lakes; nuclear fuels; organic matter; radioactivity; sediments
Abstract:
... Dissolution fluxes of stable (¹²⁷I) and radioactive (¹²⁹I) isotopes of iodine from a brackish lake sediment beside a spent nuclear fuel reprocessing plant in Japan were evaluated through two kinds of experiments: incubation using a sediment core sample for 24 h, and observation of ¹²⁷I and ¹²⁹I concentrations in sedimentary pore water. For ¹²⁷I, the dissolution flux evaluated in the incubation exp ...
DOI:
10.1016/j.jenvrad.2021.106608

37. Extreme flood events and their frequency variations during the middle to late-Holocene recorded in the sediment of Lake Suigetsu, central Japan

Author:
Yoshiaki Suzuki; Ryuji Tada; Kana Nagashima; Takeshi Nakagawa; Katsuya Gotanda; Tsuyoshi Haraguchi; Gordon Schlolaut
Source:
Holocene 2021 v.31 no.1 pp. 121-133
ISSN:
1477-0911
Subject:
Holocene epoch; Japan; bioturbation; lakes; monsoon season; rain; sediments; China
Abstract:
... Many studies are reconstructing flood records in the continental margins during the middle to late-Holocene. However, distinguishing the frequency and magnitude of flood events was difficult. Light gray event layers (GELs) in the sediment of Lake Suigetsu in Central Japan can solve this problem because they are recording the occurrence and magnitude of flood events during the last 80 years. Using ...
DOI:
10.1177/0959683620961497

38. Flux and pathway of iodine dissolution from brackish lake sediment in the northeast of Japan

Author:
Yuhi Satoh; Shoko Imai
Source:
Science of the total environment 2021 v.789 pp. 147942
ISSN:
0048-9697
Subject:
Japan; autumn; environment; iodine; lakes; organic matter; seasonal variation; sediments; summer; temperature
Abstract:
... Sediment is one of the most important entities controlling the environmental dynamics of iodine. We previously evaluated the dissolution flux of iodine from aquatic sediment to its overlying water in a brackish lake through an incubation experiment with a sediment core sample, reporting the regulation factors of this flux, such as the temperature and oxygenic conditions. In this study, factors con ...
DOI:
10.1016/j.scitotenv.2021.147942

39. GIS-Based Three-Dimensional SPH Simulation for the 11 April 2018 Yabakei Landslide at Oita Nakatsu, Japan

Author:
Zheng Han; Fan Yang; Yange Li; Jie Dou; Ningsheng Chen; Guisheng Hu; Guangqi Chen; Linrong Xu
Source:
Water 2021 v.13 no.21 pp. -
ISSN:
2073-4441
Subject:
Japan; earthquakes; geomorphology; groundwater; humans; hydrodynamics; illite; landslides; rain; rheology; sediments
Abstract:
... Landslides are usually triggered by strong earthquakes, heavy rainfalls, or intensive human activities in common wisdom. However, an unexpected landslide occurred in the Yabakei area, Nakatsu, Oita, Japan, at the pre-dawn hour 3:50 a.m. on 11 April 2018, without any accompanying rainfall and earthquake records during the event. This catastrophic landslide was 200 m in width, 110 m in height, and 6 ...
DOI:
10.3390/w13213012

40. Geomesophilobacter sediminis gen. nov., sp. nov., Geomonas propionica sp. nov. and Geomonas anaerohicana sp. nov., three novel members in the family Geobacterecace isolated from river sediment and paddy soil

Author:
Zhengcheng Zhang; Zhenxing Xu; Yoko Masuda; Xueding Wang; Natsumi Ushijima; Yutaka Shiratori; Keishi Senoo; Hideomi Itoh
Source:
Systematic and applied microbiology 2021 v.44 no.5 pp. 126233
ISSN:
0723-2020
Subject:
Geobacteraceae; Japan; acetates; agar; amino acids; chemotaxonomy; citrates; ferrihydrite; fumarates; genes; glucose; new genus; nitrates; nucleic acid hybridization; paddies; paddy soils; phylogeny; propionic acid; pyruvic acid; rivers; sediments
Abstract:
... Bacteria in the family Geobacteraceae have been proven to fill important niches in a diversity of anaerobic environments and global biogeochemical processes. Here, three bacterial strains in this family, designated Red875ᵀ, Red259ᵀ, and Red421ᵀ were isolated from river sediment and paddy soils in Japan. All of them are Gram-staining-negative, strictly anaerobic, motile, flagellum-harboring cells t ...
DOI:
10.1016/j.syapm.2021.126233

41. Harmful algal blooms and environmentally friendly control strategies in Japan

Author:
Ichiro Imai; Nobuharu Inaba; Keigo Yamamoto
Source:
Fisheries science 2021 v.87 no.4 pp. 437-464
ISSN:
0919-9268
Subject:
Alexandrium catenella; Bacillariophyceae; Chattonella; Japan; Microcystis aeruginosa; algicides; biofilm; coastal water; fish; freshwater; macroalgae; people; poisonous algae; seagrasses; sediments; toxicity
Abstract:
... The presence and status of harmful algal blooms (HABs) in Japan are reviewed, revealing a decrease in red tides; however, toxic blooms are found to be increasing in western Japan. Environmentally friendly control strategies against HABs are also compared with integrated agricultural pest management. Very high densities (10⁵–10⁸ CFU/g) of algicidal and growth-inhibiting bacteria were found in biofi ...
DOI:
10.1007/s12562-021-01524-7

42. Historical record of polychlorinated biphenyls in a sediment core from Lake Biwa, Japan: Significance of unintentional emission and weathering signals revealed by full congener-specific analysis

Author:
Anh Quoc Hoang; Daichi Aono; Isao Watanabe; Narumi K. Tsugeki; Michinobu Kuwae; Shin Takahashi
Source:
Science of the total environment 2021 v.788 pp. 147913
ISSN:
0048-9697
Subject:
Japan; analytical methods; bioturbation; environment; historical records; lakes; polychlorinated biphenyls; polymers; sediments
Abstract:
... The occurrence of 209 PCB congeners was determined in a sediment core dated between 1930 and 2019 from Lake Biwa, a typical temperate monomictic lake in Japan. Concentrations of total PCBs ranged from 5.3 to 48 ng/g dry weight (dw), showing a highest peak at the 1960s to 1970s. The temporal trend of total PCBs in this sediment core generally matched with Japanese PCB production and emission patter ...
DOI:
10.1016/j.scitotenv.2021.147913

43. Hydrodynamic and topography based cellular automaton model for simulating debris flow run-out extent and entrainment behavior

Author:
Zheng Han; Yangfan Ma; Yange Li; Hong Zhang; Ningsheng Chen; Guisheng Hu; Guangqi Chen
Source:
Water research 2021 v.193 pp. 116872
ISSN:
0043-1354
Subject:
Japan; algorithms; case studies; hydrodynamics; mass movement; models; research; roughness; sediments; topography; water
Abstract:
... As for late, studies have indicated that cellular automaton (CA) models are among the most effective solutions for simulating the extent of debris-flow run-out. However, it is currently difficult to effectively simulate both the inundated area and the erosion pattern of the debris flow process. This difficulty is caused by the lack of detailing regarding debris flow hydrodynamics as the primary co ...
DOI:
10.1016/j.watres.2021.116872

44. Impacts of freeze-thaw processes and subsequent runoff on 137Cs washoff from bare land in Fukushima

Author:
Yasunori Igarashi; Yuichi Onda; Yoshifumi Wakiyama; Kazuya Yoshimura; Hiroaki Kato; Shohei Kozuka; Ryo Manome
Source:
Science of the total environment 2021 v.769 pp. 144706
ISSN:
0048-9697
Subject:
Japan; accidents; autumn; cesium radioisotopes; environment; freeze-thaw cycles; nuclear power; particulates; power plants; rain; rill erosion; rivers; runoff; scanners; sediment yield; sediments; soil; spring; summer; topography
Abstract:
... The deposited ¹³⁷Cs is one of the long-lived radionuclides, that was released following the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, has been hydrologically transported as particulates in the terrestrial environment of the Fukushima region. The impact of freeze-thaw processes and subsequent runoff affecting the ¹³⁷Cs flux and concentration in sediment discharge were revealed in bar ...
DOI:
10.1016/j.scitotenv.2020.144706

45. Increase in sedimentary organic carbon with a change from hypoxic to oxic conditions

Author:
Mukseet Mahmood; Shunsuke Taki; Satoshi Nakai; Takehiko Gotoh; Wataru Nishijima; Akira Umehara; Tomo Aoyagi; Yuya Sato; Tomoyuki Hori; Yoko Katayama; Reka Hajdu-Rahkama; Jaakko A. Puhakka
Source:
Marine pollution bulletin 2021 v.168 pp. 112397
ISSN:
0025-326X
Subject:
Japan; biodegradation; chemical oxygen demand; dissolved organic carbon; dissolved oxygen; marine pollution; microbial communities; sediments
Abstract:
... In the Seto Inland Sea, Japan, chemical oxygen demand has increased over recent decades, while average dissolved oxygen concentrations in the bottom water have increased. In this study, we investigated responses of organic carbon (OC) in hypoxic sediment to changes of redox conditions using experimental columns containing sediment and overlying water. Surface sediment showed an increase in OC alon ...
DOI:
10.1016/j.marpolbul.2021.112397

46. Influence of surface geology on phosphorus export in coastal forested headwater catchments in Akita, Japan

Author:
Atsushi Hayakawa; Yasunari Shiraiwa; Naoki Murakami; Yuki Murayama; Tomoko Ishida; Yuichi Ishikawa; Tadashi Takahashi
Source:
Soil science and plant nutrition 2021 v.67 no.3 pp. 332-346
ISSN:
1747-0765
Subject:
Japan; calcium; dissolved inorganic nitrogen; freshwater; hydrochemistry; ion exchange; liquids; plant nutrition; reactive phosphorus; sediments; streams
Abstract:
... Surface geology is a key factor regulating the geographical patterns of P export; however, geographically extensive data on P export mechanisms from natural coastal mountain regions are lacking. We compared stream-water characteristics in forested headwater catchments with different types of surface geology (marine sedimentary rocks [MSRs] and igneous rocks [IRs]) and evaluated the factors regulat ...
DOI:
10.1080/00380768.2021.1890987

47. Interspecific variation in ephippial size between Daphnia galeata and D. pulicaria in Lake Biwa, Japan

Author:
Narumi K. Tsugeki; Mie N. Honjo; Michinobu Kuwae
Source:
Limnology 2021 v.22 no.2 pp. 197-207
ISSN:
1439-8621
Subject:
Daphnia galeata; Japan; genes; interspecific variation; lakes; limnology; mitochondria; sediments
Abstract:
... Daphnia, keystone herbivores in lakes, routinely produce immediately hatching eggs; additionally, they also produce resting eggs enveloped by an ephippial case, a thickened carapace that allows population survival under harsh environmental conditions. To examine differences in ephippial morphology between Daphnia species in different subgenera, we conducted microscopic observations and genetic ana ...
DOI:
10.1007/s10201-020-00646-8

48. Invasive Japanese foraminifera in a south-west Australian estuary

Author:
Clément M. Tremblin; Maria Holzmann; Justin H. Parker; Aleksey Sadekov; David W. Haig
Source:
Marine & freshwater research 2021 v.73 no.3 pp. 328-342
ISSN:
1323-1650
Subject:
Japan; Retaria; adults; ballast water; color; estuaries; freshwater; introduced species; research; sediments; wood chips; Brazil; California; Western Australia
Abstract:
... An invasive foraminiferan is recorded for the first time in an Australian estuary. Trochammina hadai , originally described as endemic from Japan and subsequently found to be alien in coastal waters of California and Brazil, has been identified in estuarine sediment in the vicinity of Bunbury Port in Western Australia. Species determination is based on morphological, molecular and ecological simil ...
DOI:
10.1071/MF21254

49. Long-term changes in a trochid gastropod population affected by biogenic sediment stability on an intertidal sandflat in regional metapopulation context

Author:
Akio Tamaki; Seiji Takeuchi; Soonbo Yang; Shinji Sassa
Source:
Marine biology 2021 v.168 no.3 pp. 26
ISSN:
0025-3162
Subject:
Gastropoda; Japan; Polychaeta; benthic organisms; extinction; littoral zone; plankton; sediments; shrimp; stabilizers; topography
Abstract:
... Although destabilization and stabilization of soft sediments by macro-infauna are regarded as key to understanding benthic community dynamics, how component populations are affected concurrently by both agents was poorly investigated. On an intertidal sandflat, Kyushu, Japan during 1979 − 2014 (previous study) and 2015 − 2019, monitoring was made of the populations of the filter-feeding gastropod, ...
DOI:
10.1007/s00227-021-03828-9

50. Millennial-scale vertical deformation of the Hachinohe coastal plain (NE Japan)

Author:
Yuichi Niwa; Toshihiko Sugai
Source:
Geomorphology 2021 v.389 pp. 107835
ISSN:
0169-555X
Subject:
Holocene epoch; Japan; coastal plains; coasts; deformation; earthquakes; estuaries; marshes; sea level; sediments; subduction; subsidence; tectonics
Abstract:
... We report geomorphological and sedimentological analyses in the Hachinohe plain (northernmost Sanriku coast, NE Japan) that yield new insights into vertical deformation around the source region of the 2011 Tohoku-oki earthquake. Landform classification and analyses of seven sediment cores document the transgression and regression of a sandy barrier and back-barrier estuary in a wave-dominated estu ...
DOI:
10.1016/j.geomorph.2021.107835

51. Morpho-molecular description of a new HAB species, Pseudocochlodinium profundisulcus gen. et sp. nov., and its LSU rRNA gene based genetic diversity and geographical distribution

Author:
Zhangxi Hu; Ning Xu; Haifeng Gu; Zhaoyang Chai; Kazuya Takahashi; Zhun Li; Yunyan Deng; Mitsunori Iwataki; Kazumi Matsuoka; Ying Zhong Tang
Source:
Harmful algae 2021 v.108 pp. 102098
ISSN:
1568-9883
Subject:
Cochlodinium; DNA barcoding; Japan; biogeography; coasts; data collection; discoloration; estuaries; genes; genetic variation; geographical distribution; habitats; new genus; new species; phylogeny; poisonous algae; rivers; sediments; China; South China Sea; Yellow Sea
Abstract:
... Harmful algal blooms (HABs) caused by an unknown dinoflagellate species have frequently occurred in the Pearl River Estuary, China Since 2006. These blooms were associated with severe water discoloration and economic losses, ranging from several km² to 300 km² with the maximum recorded cell density being 2.77 × 10⁷ cells⋅L⁻¹. This unknown dinoflagellate species was initially identified as Cochlodi ...
DOI:
10.1016/j.hal.2021.102098

52. Numerical Study of Discharge Adjustment Effects on Reservoir Morphodynamics and Flushing Efficiency: An Outlook for the Unazuki Reservoir, Japan

Author:
Taymaz Esmaeili; Tetsuya Sumi; Sameh A. Kantoush; Yoji Kubota; Stefan Haun; Nils Rüther
Source:
Water 2021 v.13 no.12 pp. -
ISSN:
2073-4441
Subject:
Japan; algorithms; drawdown; hydrodynamics; hydroelectric power; mathematical models; rivers; sediments; transportation; water; watersheds
Abstract:
... The Unazuki Reservoir is located on the Kurobe River, which is influenced by a catchment with one of the highest sediment yields in Japan. Due to a sufficiently available discharge during flood events, annual sediment flushing with full water-level drawdown (i.e., free-flow sediment flushing) is conducted to preserve the effective storage capacity of the reservoir. Nevertheless, the upstream half ...
DOI:
10.3390/w13121624

53. Occurrence of highly radioactive microparticles in the seafloor sediment from the pacific coast 35 km northeast of the Fukushima Daiichi nuclear power plant

Author:
Takahito Ikenoue; Masato Takehara; Kazuya Morooka; Eitaro Kurihara; Ryu Takami; Nobuyoshi Ishii; Natsumi Kudo; Satoshi Utsunomiya
Source:
Chemosphere 2021 v.267 pp. 128907
ISSN:
0045-6535
Subject:
Japan; cesium radioisotopes; clay; coasts; desorption; glass; marine environment; microparticles; nuclear power; plagioclase; power plants; quartz; radioactivity; sediments; transmission electron microscopy; wind
Abstract:
... To understand the properties and significance of highly radioactive particles in the marine environment, we have examined seafloor sediment with a radioactivity of ∼1200 Bq/kg (dry weight; after decay correction to March 2011) collected 35 km northeast of the Fukushima Daiichi Nuclear Power Plant (FDNPP). Among the 697 highly radioactive particles separated from the sediment, two particles, D1-MAX ...
DOI:
10.1016/j.chemosphere.2020.128907

54. Paleoceanographic evolution of the Japan Sea during the Pleistocene – A benthic foraminiferal perspective

Author:
Manisha Das; Raj K. Singh; Ann Holbourn; S.H. Farooq; Nishant Vats; D.K. Pandey
Source:
Palaeogeography, palaeoclimatology, palaeoecology 2021 v.566 pp. 110238
ISSN:
0031-0182
Subject:
Japan; Pleistocene epoch; Retaria; climate; evolution; glaciation; inorganic carbon; latitude; oxygen; palaeogeography; paleoceanography; paleoclimatology; paleoecology; primary productivity; sea level; sediments; solar radiation; total organic carbon; Pacific Ocean
Abstract:
... We reconstructed the paleoceanographic evolution of the Japan Sea over the Pleistocene using benthic foraminiferal and organic geochemical records from sediment cores recovered at IODP Site U1426, which was drilled at a water depth of 900 m on the Oki Ridge in the southern Japan Sea. The dominant benthic foraminiferal biofacies and the assemblage composition, total organic and inorganic carbon, co ...
DOI:
10.1016/j.palaeo.2021.110238

55. Paleoceanographic insights on meridional ventilation variations in the Japan Sea since the Last Glacial Maximum: A radiolarian assemblage perspective

Author:
Zhi Dong; Xuefa Shi; Jianjun Zou; Xinqing Zou; Ruxi Dou; Yonghua Wu; Yanguang Liu; Chendong Ge; Sergey Gorbarenko
Source:
Global and planetary change 2021 v.200 pp. 103456
ISSN:
0921-8181
Subject:
Holocene epoch; Japan; exports; glaciation; hydrology; oxygen; paleoceanography; sea ice; sediments; snowmelt; topography
Abstract:
... The Japan Sea is ideal for investigating deep water formation due to its unique topography and hydrography. However, because of the scarcity of reliable indicator and high-resolution ventilation records, the driving mechanisms behind ventilation changes in the entire Japan Sea since the Last Glacial Maximum (LGM) remain elusive. In this study, we analyze the radiolarian assemblage in three sedimen ...
DOI:
10.1016/j.gloplacha.2021.103456

56. Receiver Function Imaging of the Amphibious NE Japan Subduction Zone—Effects of Low‐Velocity Sediment Layer

Author:
HyeJeong Kim; Hitoshi Kawakatsu; Takeshi Akuhara; Masanao Shinohara; Hajime Shiobara; Hiroko Sugioka; Ryota Takagi
Source:
Journal of geophysical research 2021 v.126 no.9 pp. e2021JB021918
ISSN:
2169-9313
Subject:
Japan; data collection; geophysics; research; sediments; subduction
Abstract:
... This study presents reflectivity images of the northeast (NE) Japan subduction zone continuous across the ocean and land. As nearly half of its forearc region is under the ocean, data from ocean bottom seismometers (OBSs) must be utilized to fully image the region by passive seismic analysis. The use of OBS data has been a challenge due to inherent characters of the ocean bottom observations: high ...
DOI:
10.1029/2021JB021918

57. Riverbed fluctuation and erosion property of cohesive sediment based on long-term topographic surveys in a macrotidal estuary

Author:
Kirana Somsook; Gubash Azhikodan; Maurice A. Duka; Katsuhide Yokoyama
Source:
Regional studies in marine science 2021 v.45 pp. 101848
ISSN:
2352-4855
Subject:
Japan; erodibility; estuaries; friction velocity; marine science; river flow; rivers; salinity; sediments; shear stress; stream channels; topography; turbidity
Abstract:
... The feature of large scouring process of cohesive sediment and the long term seasonal riverbed fluctuation at the estuarine turbidity maximum (ETM) zone of the macrotidal Chikugo River estuary, Japan were studied using the intensive periodical transverse surveys of riverbed topography and sediment sampling along with continuous monitoring of water level, salinity and turbidity during 2005–2017. Th ...
DOI:
10.1016/j.rsma.2021.101848

58. Seagrass contributes substantially to the sedimentary lignin pool in an estuarine seagrass meadow

Author:
Masatoshi Nakakuni; Kenta Watanabe; Khoki Kaminaka; Yukiko Mizuno; Keiko Takehara; Tomohiro Kuwae; Shuichi Yamamoto
Source:
Science of the total environment 2021 v.793 pp. 148488
ISSN:
0048-9697
Subject:
Bayesian theory; Japan; biomarkers; blue carbon; carbon sequestration; cutin; environment; estuaries; lignin; microalgae; organic carbon; seagrasses; sediments
Abstract:
... Shallow coastal ecosystems are reservoirs of carbon derived from allochthonous organic matter and autochthonous organic matter produced by microalgae and macrophytes. Carbon stored in vegetated coastal ecosystems has attracted broad attention as an important component of carbon sinks. Characterizing the source of carbon in sediments is essential for quantifying the carbon-sequestration function of ...
DOI:
10.1016/j.scitotenv.2021.148488

59. Significance of Fukushima-derived radiocaesium flux via river-estuary-ocean system

Author:
Shota Kambayashi; Jing Zhang; Hisashi Narita
Source:
Science of the total environment 2021 v.793 pp. 148456
ISSN:
0048-9697
Subject:
Japan; cesium radioisotopes; coasts; desorption; estuaries; marine environment; models; nuclear power; power plants; riparian areas; salinity; seawater; sediments
Abstract:
... The environmental dynamics of Fukushima-derived radiocaesium from land to ocean and the impact of its flux on the marine environment are matters of concern because radiocaesium will be continually transported to the open ocean for the next several decades, or possibly more than one hundred years. In order to assess the distribution and flux of radiocaesium in a river-estuary-ocean system, we inves ...
DOI:
10.1016/j.scitotenv.2021.148456

60. Spatial Patterns in Frictional Behavior of Sediments Along the Kumano Transect in the Nankai Trough

Author:
Hanaya Okuda; Matt J. Ikari; Alexander Roesner; Katja Stanislowski; Andre Hüpers; Asuka Yamaguchi; Achim J. Kopf
Source:
Journal of geophysical research 2021 v.126 no.11 pp. e2021JB022546
ISSN:
2169-9313
Subject:
Japan; clay; friction; geophysics; mineral content; models; research; sediments; subduction; Pacific Ocean
Abstract:
... Fault slip activity at subduction zones is governed by sediment frictional properties, which in turn are affected by diagenetic processes. To study the spatial patterns in frictional properties across the Nankai Trough, SW Japan, and their relations to fault slip activity, we used sediment samples (10%–59% clay mineral content) along the Kumano transect covering a large spatial range from the inpu ...
DOI:
10.1029/2021JB022546

61. Spatiotemporal change of cesium-137 in the Pacific coast of Tohoku, Japan: The mussel watch approach

Author:
Naoko Murakami-Sugihara; Kotaro Shirai; Hirofumi Tazoe; Kaoruko Mizukawa; Hideshige Takada; Takeyasu Yamagata; Shigeyoshi Otosaka; Hiroshi Ogawa
Source:
Marine pollution bulletin 2021 v.168 pp. 112413
ISSN:
0025-326X
Subject:
Japan; cesium radioisotopes; coasts; marine pollution; mussels; seawater; sediments; soil
Abstract:
... We measured radiocesium in mussel tissue collected from the Pacific coast of Tohoku from 2011 to 2015 to investigate the temporal and spatial dynamics of radiocesium in the coastal area. Radioactive ¹³⁷Cs was detected in all the samples collected in 2011, but it was not found in samples from localities north of Sendai after 2012. In contrast, ¹³⁷Cs was detected in many sites in the Fukushima area ...
DOI:
10.1016/j.marpolbul.2021.112413

62. Spatiotemporally varying inter-relationships between mainstem riverbed elevation and tributary sediment supply since the last interglacial in the upper Ara River, central Japan

Author:
Takayuki Takahashi; Toshihiko Sugai
Source:
Geomorphology 2021 v.383 pp. 107697
ISSN:
0169-555X
Subject:
Holocene epoch; Japan; drainage; floodplains; mass movement; river valleys; rivers; sediment transport; sediments; stream channels; watersheds
Abstract:
... The dynamics of sediment transport processes over millennial time scales in mountain river valleys remain poorly understood, limiting our overall understanding of sediment routing through river basins. Here, we reconstruct changes of the mainstem riverbed elevation, tributary sediment supply processes, and their inter-relationships since the last interglacial in the upper Ara River valley, central ...
DOI:
10.1016/j.geomorph.2021.107697

63. The Kiryu Experimental Watershed: 50‐years of rainfall‐runoff data for a forest catchment in central Japan

Author:
Masanori Katsuyama; Nobuhito Ohte; Yoshiko Kosugi; Makoto Tani
Source:
Hydrological processes 2021 v.35 no.3 pp. e14104
ISSN:
0885-6087
Subject:
Chamaecyparis obtusa; Japan; climatic factors; forest plantations; forested watersheds; hills; hydrologic data; rain; runoff; sediment transport; sediments; soil; soil erosion; wood industry
Abstract:
... The Kiryu Experimental Catchment (KEW) is a small (5.99 ha) forest catchment located in Shiga Prefecture, central Japan (34°58′ N, 136°00′ E; www.bluemoon.kais.kyoto-u.ac.jp/kiryu/contents.html). Around this area, forest devastation occurred from ca. 1250 to ca. 150 years ago because of overuse of forest and timbers. Then, hillside forestation was carried out for more than 100 years to prevent soi ...
DOI:
10.1002/hyp.14104

64. The Relative Effects of Biotic and Abiotic Factors on the Recruitment of Freshwater Mussels (Margaritifera laevis)

Author:
Keita Kawajiri; Nobuo Ishiyama; Kazuki Miura; Akira Terui; Masanao Sueyoshi; Futoshi Nakamura
Source:
Water 2021 v.13 no.9 pp. -
ISSN:
2073-4441
Subject:
Japan; Margaritifera; Oncorhynchus masou; fish diseases; freshwater; juveniles; larval development; population density; salmon; sediments; water quality; water temperature
Abstract:
... Freshwater mussels, Unionoida, are endangered across the globe due to recruitment failure. In the present study, with general linear mixed models, we investigated the relative effects of biotic (host fish density) and abiotic (water depth, fine sediment, water temperature, and water quality) factors on the recruitment of Margaritifera laevis in 10 streams of Hokkaido, northern Japan. We additional ...
DOI:
10.3390/w13091289

65. The influence and impact of tsunamis on the microorganism assembly of Nagatsura-Ura Lagoon, Miyagi, northeastern Japan

Author:
Yutaka Okumura; Hiromi Matsuoka; Hisayuki Arakawa; Fuyuki Tokanai; Atsushi Suzuki; Toshiaki Irizuki; Hiroto Kajita; Motoyuki Hara
Source:
Fisheries science 2021 v.87 no.1 pp. 121-130
ISSN:
0919-9268
Subject:
Alexandrium; Bacillariophyceae; Chaetoceros; Japan; chlorophyll; earthquakes; phytoplankton; seawater; sediments; tsunamis
Abstract:
... Two sediment cores were collected from two sites in Nagatsura-Ura Lagoon, the mouth of which was destroyed in the 2011 Tohoku-oki tsunami. Although sediment conditions differed widely between the central and inner parts of the lagoon, we could identify traces of the 2011 Tohoku-oki tsunami at both, and those of earlier tsunamis in the inner part of the lagoon. Chlorophyll a maxima were observed at ...
DOI:
10.1007/s12562-020-01472-8

66. The middle to Late Holocene environment on the Iturup Island (kurils, North Western Pacific)

Author:
Larisa Nazarova; Nadezhda G. Razjigaeva; Larisa A. Ganzey; Tatiana R. Makarova; Marina S. Lyashevskaya; Boris K. Biskaborn; Philipp Hoelzmann; Larisa V. Golovatyuk; Bernhard Diekmann
Source:
Quaternary international 2021 pp. -
ISSN:
1040-6182
Subject:
Bacillariophyceae; Chironomidae; Holocene epoch; Japan; Russia; climate; cold; cooling; freshwater; ice; lakes; marine environment; paleoecology; pollen; sea level; sediments; tectonics; Okhotsk Sea; Pacific Ocean
Abstract:
... The Kuril Islands stretch southwest from Kamchatka, Russia, to Hokkaido, Japan and separate the Sea of Okhotsk from the northern Pacific Ocean. A series of transgressions and regressions linked to variations in climatically affected global ice volume are among the most important drivers of Holocene environmental changes in the region. Despite a long research history, reconstructions of the Holocen ...
DOI:
10.1016/j.quaint.2021.05.003

67. Thiosulfativibrio zosterae gen. nov., sp. nov., and Thiosulfatimonas sediminis gen. nov., sp. nov.

Author:
Jun Mochizuki; Hisaya Kojima; Manabu Fukui
Source:
Archives of microbiology 2021 v.203 no.3 pp. 951-957
ISSN:
0302-8933
Subject:
Japan; Zostera marina; chromosomes; genes; lakes; pH; quinones; sediments; sulfides; sulfur; temperature
Abstract:
... Aerobic, Gram-stain-negative, obligately chemolithoautotrophic thiosulfate-oxidizing bacteria, strains AkT22ᵀ and aks77ᵀ were isolated from a brackish lake in Japan. Strains AkT22ᵀ and aks77ᵀ were isolated from samples of eelgrass and sediment, respectively. Growth on sulfide, tetrathionate, elemental sulfur, and organic substrates was not observed for both strains. Growth of the strains was obser ...
DOI:
10.1007/s00203-020-02090-9

68. Trace metal geochemical and Zn stable isotope data as tracers for anthropogenic metal contributions in a sediment core from Lake Biwa, Japan

Author:
Kai Nils Nitzsche; Toshihiro Yoshimura; Naoto F. Ishikawa; Nanako O. Ogawa; Katsuhiko Suzuki; Naohiko Ohkouchi
Source:
Applied geochemistry 2021 v.134 pp. 105107
ISSN:
0883-2927
Subject:
Japan; basins; freshwater lakes; geochemistry; industrialization; municipal wastewater; paddies; pollution; runoff; sediments; stable isotopes; urbanization; watersheds; zinc
Abstract:
... The catchment of Lake Biwa, the largest freshwater lake in Japan, has experienced rapid urbanization and industrialization in the second half of the 20th century; yet little is known about the historical trend of metal pollution. We analyzed the elemental concentrations and zinc stable isotope ratios (δ⁶⁶Zn) in a sediment core from the Northern basin of the lake. The goals were 1) to reconstruct t ...
DOI:
10.1016/j.apgeochem.2021.105107

69. Use of comprehensive target analysis for determination of contaminants of emerging concern in a sediment core collected from Beppu Bay, Japan

Author:
Kou Nishimuta; Daisuke Ueno; Shin Takahashi; Michinobu Kuwae; Kiwao Kadokami; Takashi Miyawaki; Hidenori Matsukami; Hidetoshi Kuramochi; Taiki Higuchi; Yuki Koga; Hideaki Matsumoto; Noriko Ryuda; Hideki Miyamoto; Tomokazu Haraguchi; Shin-Ichi Sakai
Source:
Environmental pollution 2021 v.272 pp. 115587
ISSN:
0269-7491
Subject:
Japan; anthracenes; automation; liquid chromatography; phosphates; pollutants; pollution; sediments; toxicity
Abstract:
... In recent years, concern about the release of anthropogenic organic micropollutants referred to as contaminants of emerging concern (CECs) has been growing. The objective of this study was to find potential CECs by means of an analytical screening method referred to as comprehensive target analysis with an automated identification and quantification system (CTA-AIQS), which uses gas and liquid chr ...
DOI:
10.1016/j.envpol.2020.115587

70. Variation in rainfall patterns triggering debris flow in the initiation zone of the Ichino-sawa torrent, Ohya landslide, Japan

Author:
Haruka Tsunetaka; Norifumi Hotta; Fumitoshi Imaizumi; Yuichi S. Hayakawa; Takeshi Masui
Source:
Geomorphology 2021 v.375 pp. 107529
ISSN:
0169-555X
Subject:
Japan; freeze-thaw cycles; landslides; mountains; rain; sediment yield; sediments; summer; watersheds; winter
Abstract:
... Rainfall patterns that trigger debris flows may vary depending on the amount of sediment storage in their initiation zones. However, the current literature did not fully explore the relationship between the rainfall patterns triggering debris flows and changes in sediment storage. In this study, we investigated the variation in rainfall patterns for debris-flow occurrences via field-based, four-ye ...
DOI:
10.1016/j.geomorph.2020.107529

71. A new radiolarian transfer function for the Pacific Ocean and application to fossil records: Assessing potential and limitations for the last glacial-interglacial cycle

Author:
Iván Hernández-Almeida; Demetrio Boltovskoy; Svetlana B. Kruglikova; Giuseppe Cortese
Source:
Global and planetary change 2020 v.190 pp. 103186
ISSN:
0921-8181
Subject:
autocorrelation; climate; data collection; environmental factors; fossils; latitude; multivariate analysis; sediments; surface water temperature; Bering Sea; Japan; Okhotsk Sea; Pacific Ocean
Abstract:
... Climatic and oceanographic processes in the Pacific Ocean have global implications. Reliable sedimentary proxies in this region are thus necessary to understand the magnitude of past climate variability. Radiolarian assemblages are of particular relevance in some regions of the Pacific Ocean where other proxies are either poorly preserved or are biased towards a specific season. Previously publish ...
DOI:
10.1016/j.gloplacha.2020.103186

72. Adopting deep learning methods for airborne RGB fluvial scene classification

Author:
Patrice E. Carbonneau; Stephen J. Dugdale; Toby P. Breckon; James T. Dietrich; Mark A. Fonstad; Hitoshi Miyamoto; Amy S. Woodget
Source:
Remote sensing of environment 2020 v.251 pp. 112107
ISSN:
0034-4257
Subject:
Japan; data collection; environment; humans; image interpretation; labor; land cover; landscapes; neural networks; riparian areas; rivers; sediments; statistical analysis; vegetation; Canada; Costa Rica; Italy; United Kingdom
Abstract:
... Rivers are among the world's most threatened ecosystems. Enabled by the rapid development of drone technology, hyperspatial resolution (<10 cm) images of fluvial environments are now a common data source used to better understand these sensitive habitats. However, the task of image classification remains challenging for this type of imagery and the application of traditional classification algorit ...
DOI:
10.1016/j.rse.2020.112107

73. Alien worm in worm: a new genus of endoparasitic polychaete (Phyllodocidae, Annelida) from scale worms (Aphroditidae and Polynoidae, Annelida)

Author:
Naoto Jimi; Taeko Kimura; Akito Ogawa; Hiroshi Kajihara
Source:
Systematics and biodiversity 2020 v.19 no.1 pp. 13-21
ISSN:
1478-0933
Subject:
Japan; Phyllodocidae; biodiversity; endoparasites; new genus; phylogeny; sediments
Abstract:
... Up to now, 19 species in eight genera and two families (Dorvilleidae and Oenonidae) of polychaetes are known to be endoparasitic in the body of other polychaetes. In this paper, we describe Endovermis seisuiae gen. et sp. nov. as the first representative of Phyllodocidae parasitizing other polychaetes. Specimens of E. seisuiae were found in the body cavity of Aphrodita sp. (Aphroditidae) and Lepid ...
DOI:
10.1080/14772000.2020.1785038

74. Analysis of environmental and microbiological changes in Onagawa Bay immediately after the tsunami of the Great East Japan Earthquake based on sediment cores

Author:
Yutaka Okumura; Kenji Kaneko; Hiroto Ota; Hiromitsu Nagasaka; Motoyuki Hara
Source:
Marine pollution bulletin 2020 v.157 pp. 111235
ISSN:
0025-326X
Subject:
DNA; Japan; Miozoa; chlorophyll; earthquakes; marine pollution; phytoplankton; sediments; tsunamis
Abstract:
... We investigated two sediment cores to understand whether a tsunami in Onagawa Bay, Japan caused environmental changes. The value of δ¹³C ranged from −21.9‰ to −24.3‰ and of δ¹⁵N ranged from 5.1 to 5.9‰. We conclude that the source of the sediment in the present study area was mainly oceanic and not terrestrial. The chlorophyll concentration ranged from 1.8 to 4.0 μg/g ww, and did not vary greatly ...
DOI:
10.1016/j.marpolbul.2020.111235

75. Carbaryl residue concentrations, degradation, and major sinks in the Seto Inland Sea, Japan

Author:
Aly Derbalah; Russel Chidya; Chikumbusko Kaonga; Yoko Iwamoto; Kazuhiko Takeda; Hiroshi Sakugawa
Source:
Environmental science and pollution research international 2020 v.27 no.13 pp. 14668-14678
ISSN:
0944-1344
Subject:
Japan; biodegradation; carbaryl; fish; half life; human health; hydrolysis; models; photolysis; plankton; pollution; research; river water; rivers; seawater; sediments
Abstract:
... The fate of carbaryl in the Seto Inland Sea (west Japan) was predicted using a mass distribution model using carbaryl concentrations in river and sea water samples, degradation data, and published data. The predicted carbaryl concentrations in water in Kurose River and the Seto Inland Sea were 4.320 and 0.2134 μg/L, respectively, and the predicted concentrations in plankton, fish, and sediment wer ...
DOI:
10.1007/s11356-020-08010-0

76. Catchment topography and the distribution of electron donors for denitrification control the nitrate concentration in headwater streams of the Lake Hachiro watershed

Author:
Atsushi Hayakawa; Yu Funaki; Tatsuya Sudo; Ryoki Asano; Hirotatsu Murano; Shintaro Watanabe; Tomoko Ishida; Yuichi Ishikawa; Shin Hidaka
Source:
Soil science and plant nutrition 2020 v.66 no.6 pp. 906-918
ISSN:
1747-0765
Subject:
Japan; cells; correlation; denitrification; digital elevation models; information; lakes; linear models; measurement; nitrates; nitrous oxide; plant nutrition; riparian areas; sampling; sedimentary rocks; sediments; soil organic carbon; spatial variation; stream channels; subsoil; sulfides; topography; water; watersheds
Abstract:
... We examined the linkages between topography and electron donors for denitrification on in-stream NO₃ ⁻ concentration in headwater catchments in the Lake Hachiro watershed having marine sedimentary rock, Japan. In 35 headwater catchments (0.07–16.9 km²), we sampled stream water every season in 2 years. The water samples were analyzed for NO₃ –, dissolved nitrous oxide (dN₂O), and SO₄ ² – concentrat ...
DOI:
10.1080/00380768.2020.1827292

77. Characteristics of sediment dynamics following large-scale sediment supply events in mountain watersheds in Japan

Author:
Hiroaki Izumiyama; Taro Uchida; Katsuya Horie; Wataru Sakurai
Source:
Geomorphology 2020 v.367 pp. 107301
ISSN:
0169-555X
Subject:
basins; earthquakes; rain; risk; rivers; sediment yield; sediments; time series analysis; topographic slope; watersheds; Japan
Abstract:
... Large-scale sediment supply events (LSEs) cause not only a sudden increase in sediment discharge immediately after their occurrence, but also a long-term condition of elevated sediment yield. In Japan, many LSEs, triggered by heavy rainfall or earthquakes have created high risks for sediment-related disaster. However, the difference between sediment dynamics following a LSE triggered by rainfall a ...
DOI:
10.1016/j.geomorph.2020.107301

78. Characterization of mono- to deca-chlorinated biphenyls in a well-preserved sediment core from Beppu Bay, Southwestern Japan: Historical profiles, emission sources, and inventory

Author:
Shin Takahashi; Hoang Quoc Anh; Isao Watanabe; Daichi Aono; Michinobu Kuwae; Tatsuya Kunisue
Source:
Science of the total environment 2020 v.743 pp. 140767
ISSN:
0048-9697
Subject:
Japan; dechlorination; environment; inventories; sediments
Abstract:
... Contamination levels and profiles of mono- to deca-chlorinated biphenyls (PCBs) were characterized in a sediment core dated in 1954–2011 from Beppu Bay, southwestern Japan, providing a comprehensive and detailed picture on the environmental occurrence, temporal trends, and emission sources of these pollutants in the study area. Concentrations of total PCBs in the core ranged from 3.5 to 150 (media ...
DOI:
10.1016/j.scitotenv.2020.140767

79. Control of radiocesium recontamination by plant removal along a decontaminated riverside in Fukushima, Japan

Author:
Takuhei Yamasaki; Tatsuhiro Nishikiori; Satoshi Suzuki
Source:
Journal of environmental management 2020 v.270 pp. 110856
ISSN:
0301-4797
Subject:
Japan; accidents; air; decontamination; environmental management; nuclear power; phytomass; power plants; rain; risk; sediments
Abstract:
... The accident at the Fukushima Dai-ichi Nuclear Power Plant in March 2011 resulted in the widespread deposition of radiocesium in and around Fukushima prefecture. Riversides have an additional contamination risk through deposition of material containing radiocesium transported from upstream. In our previous research (Nishikiori and Suzuki, 2017) we developed a decontamination method in a river bank ...
DOI:
10.1016/j.jenvman.2020.110856

80. Description of Three Novel Members in the Family Geobacteraceae, Oryzomonas japonicum gen. nov., sp. nov., Oryzomonas sagensis sp. nov., and Oryzomonas ruber sp. nov.

Author:
Zhenxing Xu; Yoko Masuda; Chie Hayakawa; Natsumi Ushijima; Keisuke Kawano; Yutaka Shiratori; Keishi Senoo; Hideomi Itoh
Source:
Microorganisms 2020 v.8 no.5 pp. -
ISSN:
2076-2607
Subject:
Geobacteraceae; Japan; agar; amino acids; chemotaxonomy; citrates; ferrihydrite; freshwater; genomics; malates; methanol; new genus; nucleic acid hybridization; paddies; phylogeny; pyruvic acid; sediments
Abstract:
... Bacteria of the family Geobacteraceae are particularly common and deeply involved in many biogeochemical processes in terrestrial and freshwater environments. As part of a study to understand biogeochemical cycling in freshwater sediments, three iron-reducing isolates, designated as Red96ᵀ, Red100ᵀ, and Red88ᵀ, were isolated from the soils of two paddy fields and pond sediment located in Japan. Th ...
DOI:
10.3390/microorganisms8050634

81. Differences in conservation candidate tidal rivers by cross‐taxon analysis in the Japanese temperate zone

Author:
Akihiko Koyama; Ryutei Inui; Kazuki Kanno; Katsuhisa Eguchi; Atsushi Tanabe; Jun Nakajima; Norio Onikura; Tomoko Minagawa
Source:
Aquatic conservation 2020 v.30 no.12 pp. 2313-2326
ISSN:
1052-7613
Subject:
Gobiiformes; Japan; anthropogenic activities; biodiversity conservation; crabs; estuaries; habitats; littoral zone; salt marshes; sediments; temperate zones
Abstract:
... 1.For effective biodiversity conservation, verifying the correspondence of conservation sites among taxa and identifying the environmental characteristics of these sites are essential; however, only a few such studies have been performed in estuaries. The aim of the present study was to verify the surrogacy of estuarine gobies and crabs, to identify tidal rivers of high conservation priority, and ...
DOI:
10.1002/aqc.3377

82. Differences in fish assemblage structures between tidal marsh and bare sandy littoral habitats in a brackish water lake, eastern Japan

Author:
Seiya Kaneko; Kouki Kanou; Mitsuhiko Sano
Source:
Ichthyological research 2020 v.67 no.3 pp. 439-450
ISSN:
1341-8998
Subject:
Acanthogobius; Crustacea; Phragmites australis; Salangichthys microdon; benthic organisms; brackish water; dominant species; epiphytes; fish; fishery resources; food availability; habitats; lakes; littoral zone; salt marshes; sediments; species richness; surface water; water quality; zooplankton; Japan
Abstract:
... Fish assemblage structures and environmental properties (e.g., water quality, sediment condition and prey abundance) were compared between tidal marshes, dominated by the common reed Phragmites australis, and bare sandy areas in the brackish-water Lake Hinuma, eastern Japan, by daytime seine net sampling in October 2014, and January, April and July 2015. A total of 4,076 fish individuals from 30 s ...
DOI:
10.1007/s10228-020-00739-5

83. Dissolved and Particulate Organic Matter Dynamics Relative to Sediment Resuspension Induced by the Tidal Cycle in Macrotidal Estuaries, Kyushu, Japan

Author:
Hiroyuki Takasu; Koji Uchino; Koichiro Mori
Source:
Water 2020 v.12 no.9 pp. -
ISSN:
2073-4441
Subject:
Japan; fluorescence; organic nitrogen; particulate organic carbon; riparian areas; rivers; salinity; sediments; turbidity; water
Abstract:
... The tide-induced resuspension of sediments plays important roles in the efflux of particulate organic carbon (POC) from rivers to the coastal sea. Although dissolved organic carbon (DOC) comprises more than half of the riverine flux of organic carbon to the ocean, the influence of sediment resuspension induced by the tidal cycle on DOC dynamics is largely unknown. This study examined the dynamics ...
DOI:
10.3390/w12092561

84. Does the dispersal of fairy shrimps (Branchiopoda, Anostraca) reflect the shifting geographical distribution of freshwaters since the late Mesozoic?

Author:
Hidetoshi Naganawa; Elena Yu. Naumova; Natalia N. Denikina; Ilya G. Kondratov; Elena V. Dzyuba; Atsushi Iwasawa
Source:
Limnology 2020 v.21 no.1 pp. 25-34
ISSN:
1439-8621
Subject:
Branchinecta; Mesozoic era; aquatic plants; coasts; fossils; genes; genetic distance; geographical distribution; lakes; phylogeny; refuge habitats; ribosomal DNA; ribosomal RNA; sediments; shorelines; steppes; surface water; watersheds; Japan; Lake Baikal; Russia
Abstract:
... Order Anostraca (fairy shrimp of large branchiopods) is a primitive crustacean group, retaining ancient forms and ecology. The Holarctic family Chirocephalidae originated over 100 million years ago; it is a very long-lived freshwater taxon that has survived from the Mesozoic to the present. Thus, using this taxon as an indicator, we verified how the geographical distribution of freshwaters shifted ...
DOI:
10.1007/s10201-019-00589-9

85. Dominating factors influencing rapid meander shift and levee breaches caused by a record-breaking flood in the Otofuke River, Japan

Author:
Tomoko Kyuka; Kazunori Okabe; Yasuyuki Shimizu; Satomi Yamaguchi; Kazuyoshi Hasegawa; Kho Shinjo
Source:
Journal of hydro-environment research 2020 v.31 pp. 76-89
ISSN:
1570-6443
Subject:
Japan; bank erosion; research; riparian areas; rivers; sediment transport; sediments; surveys; typhoons; vegetation
Abstract:
... The Otofuke River is a tributary of the Tokachi River, Hokkaido Japan, consisting of a channelized reach with a steep slope and a relatively large designed width. In August 2016, the river witnessed four major flooding events with a record-breaking discharge within a time span of 15 days. The Otofuke River originally had a straight channelized reach. However, because of a series of flooding events ...
DOI:
10.1016/j.jher.2020.05.003

86. Effect of Crab Burrows on CO2 Flux from the Sediment Surface to the Atmosphere in a Subtropical Mangrove Forest on Ishigaki Island, Southwestern Japan

Author:
Mitsutoshi Tomotsune; Hideshi Arai; Shinpei Yoshitake; Morimaru Kida; Nobuhide Fujitake; Kazutoshi Kinjo; Toshiyuki Ohtsuka
Source:
Estuaries and coasts 2020 v.43 no.1 pp. 102-110
ISSN:
1559-2723
Subject:
aerobic conditions; burrows; carbon dioxide; carbon dioxide production; carbon sinks; crabs; forest litter; mangrove forests; phenology; sediments; species diversity; surface area; temperature; water content; Japan
Abstract:
... To clarify the effects of crab burrows on variation in sediment CO₂ flux in mangrove forest, we measured the traits of crab burrows (density and entrance area size) and the CO₂ flux rate from sediment surfaces, in areas with and without burrows, in a subtropical mangrove forest on Ishigaki Island, southwestern Japan. Burrow density and entrance area showed significant differences among seasons (wa ...
DOI:
10.1007/s12237-019-00667-2

87. Effects of increasing concentrations of fine suspended sediment on the survival, growth, condition factor and gill condition of artificially reared juveniles of Oncorhynchus masou, Salvelinus leucomaenis and Plecoglossus altivelis

Author:
Keishi Matsuda
Source:
Aquaculture research 2020 v.51 no.3 pp. 972-981
ISSN:
1355-557X
Subject:
Oncorhynchus masou; Plecoglossus altivelis; Salvelinus leucomaenis; aquaculture; artificial rearing; condition factor; habitats; juveniles; sediments; survival rate; suspended sediment; turbidity; Japan
Abstract:
... Little is known about the effect of chronic turbidity created by fine suspended sediment on the health and growth of artificially reared Oncorhynchus masou, Salvelinus leucomaenis and Plecoglossus altivelis—three important aquaculture species in Japan. This study compared survival rate, daily growth rate, condition factor (estimated from the ratio of standard length to weight) and gill condition a ...
DOI:
10.1111/are.14442

88. End-Guadalupian extinction of larger fusulinids in central Iran and implications for the global biotic crisis

Author:
Sakineh Arefifard; Jonathan L. Payne
Source:
Palaeogeography, palaeoclimatology, palaeoecology 2020 v.550 pp. 109743
ISSN:
0031-0182
Subject:
Capitanian age; Lopingian epoch; Retaria; carbonates; corals; extinction; marine ecosystems; sediments; shale; volcanic activity; China; Iran; Japan; Thailand
Abstract:
... The end-Guadalupian (Capitanian) biotic crisis was less intense than its end-Permian counterpart but highly selective against certain groups of tropical organisms, such as rugose corals and keriothecal-walled fusulinid foraminifera. The causes of this event remain debated, in part due to apparent disagreement among stratigraphic sections in the timing of taxonomic losses. In order to further const ...
DOI:
10.1016/j.palaeo.2020.109743

89. Estimation of spatiotemporal variations in nutrient fluxes from sediments in the seasonally hypoxic Omura Bay, Japan

Author:
Naoki Muta; Yu Umezawa; Akira Yamaguchi; Hirokazu Suzaki; Minoru Wada; Hideaki Nakata; Kazuaki Kawamoto; Kazumi Matsuoka
Source:
Limnology 2020 v.21 no.3 pp. 341-356
ISSN:
1439-8621
Subject:
Japan; limnology; organic matter; sediment-water interface; sediments; summer; water temperature
Abstract:
... In the seasonally hypoxic semi-enclosed Omura Bay, Japan, regression equations estimating year-round nutrient [NO₃ + NO₂, NH₄, PO₄, Si(OH)₄] concentrations in pore water were successfully constructed based on water temperature and the concentration of biogenic elements in surface sediments, except for NH₄ and PO₄ concentrations in summer when the hypoxic water mass develops. Core incubation studie ...
DOI:
10.1007/s10201-019-00591-1

90. Evaluation of a virus-based control method to protect cultured oysters from the harmful dinoflagellate Heterocapsa circularisquama

Author:
Natsuko Nakayama; Masami Hamaguchi; Hiroaki Yamaguchi; Ken Masuda; Masatsugu Fujiwara
Source:
Aquaculture 2020 v.529 pp. 735625
ISSN:
0044-8486
Subject:
Heterocapsa circularisquama; algal blooms; analysis of variance; clams; control methods; environmental impact; laboratory experimentation; mutation; oyster culture; oysters; sediments; spraying; ssRNA viruses; viruses; Japan
Abstract:
... This study evaluates a novel control method for harmful algal blooms (HABs) that uses natural sediment including associated viruses. In Japan, commercial aquaculture of bivalves such as oysters, pearl oysters and clams is severely threatened by blooms of the harmful dinoflagellate, Heterocapsa circularisquama. HcRNAV is a single-stranded RNA virus that specifically infects H. circularisquama. Give ...
DOI:
10.1016/j.aquaculture.2020.735625

91. Evaluation of dissolution flux of iodine from brackish lake sediments under different temperature and oxygenic conditions

Author:
Yuhi Satoh; Shoko Imai
Source:
Science of the total environment 2020 v.707 pp. 135920
ISSN:
0048-9697
Subject:
absorption; aerobic conditions; air flow; iodates; iodine; isotopes; lakes; nitrogen; nuclear fuels; regression analysis; sediments; temperature; Japan; Pacific Ocean
Abstract:
... Dissolution flux of iodine from aquatic sediments in a brackish lake (Lake Obuchi), facing the Pacific Ocean and adjacent to a nuclear fuel reprocessing plant in northeast Japan, was evaluated using incubation experiments on sediment core samples. The experiments were performed under three different temperatures (29, 17, and 6 °C) and oxygenic (air flow, N₂ gas flow, and untreated) conditions for ...
DOI:
10.1016/j.scitotenv.2019.135920

92. Genomic and geochemical identification of the long-chain alkenone producers in the estuarine Lake Takahoko, Japan: Implications for temperature reconstructions

Author:
Hiroto Kajita; Hideto Nakamura; Naohiko Ohkouchi; Naomi Harada; Miyako Sato; Shun Tokioka; Hodaka Kawahata
Source:
Organic geochemistry 2020 v.142 pp. 103980
ISSN:
0146-6380
Subject:
Isochrysis galbana; estuaries; genomics; lakes; phylotype; ribosomal DNA; sediments; summer; water temperature; Japan; United States
Abstract:
... Identifying the lacustrine haptophyte species that produce long-chain alkenones (LCAs) is essential for using alkenone unsaturation ratios to create lake water temperature reconstructions. We discovered LCAs in the brackish Lake Takahoko in northern Japan. The identity of LCA-producing species was investigated using 18S ribosomal DNA (rDNA) and organic geochemical analysis. Two distinct genetic gr ...
DOI:
10.1016/j.orggeochem.2020.103980

93. Improving Water Leaving Reflectance Retrievals from ABI and AHI Data Acquired Over Case 2 Waters from Present Geostationary Weather Satellite Platforms

Author:
Bo-Cai Gao; Rong-Rong Li
Source:
Remote Sensing 2020 v.12 no.19 pp. -
ISSN:
2072-4292
Subject:
Japan; aerosols; algorithms; chlorophyll; coastal water; color; data collection; image analysis; land; models; oceans; reflectance; remote sensing; satellites; sediments; weather
Abstract:
... The current generation of geostationary weather satellite instruments, such as the Advanced Baseline Imagers (ABIs) on board the US NOAA GOES 16 and 17 satellites and the Advanced Himawari Imagers (AHIs) on board the Japanese Himawari-8/9 satellites, have six channels located in the visible to shortwave IR (SWIR) spectral range. These instruments can acquire images over both land and water surface ...
DOI:
10.3390/rs12193257

94. Interannual variations in abundance and distribution of Chattonella cysts, and the relationship to population dynamics of vegetative cells in the Yatsushiro Sea, Japan

Author:
Goh Onitsuka; Mineo Yamaguchi; Setsuko Sakamoto; Tomoyuki Shikata; Natsuko Nakayama; Saho Kitatsuji; Shigeru Itakura; Kiyonari Sakurada; Hidenori Ando; Naoaki Yoshimura; Hirohiko Mukai; Hirokazu Yamashita
Source:
Harmful algae 2020 v.96 pp. 101833
ISSN:
1568-9883
Subject:
Chattonella; El Nino; environmental factors; germination; poisonous algae; population dynamics; regression analysis; sediments; solar radiation; spring; summer; temperature; vegetative cells; Japan
Abstract:
... The fish-killing raphidophytes Chattonella spp. have a resting cyst stage. To investigate the abundance and distribution of Chattonella cysts and determine their relationship to the population dynamics of vegetative cells, we conducted field observations from 2002 to 2017 in the Yatsushiro Sea, a semi-enclosed embayment in Japan, and analyzed the data including environmental conditions. Analysis o ...
DOI:
10.1016/j.hal.2020.101833

95. Late Jurassic to early Early Cretaceous tectonic nature on the NE Asian continental margin: Constraints from Mesozoic accretionary complexes

Author:
Yu Li; Wen-Liang Xu; Ri-Xiang Zhu; Feng Wang; Wen-Chun Ge; A.A. Sorokin
Source:
Earth-science reviews 2020 v.200 pp. 103042
ISSN:
0012-8252
Subject:
Early Cretaceous epoch; Early Jurassic epoch; Late Jurassic epoch; igneous rocks; provenance; sandstone; seamounts; sediments; subduction; tectonics; zircon; China; Eurasia; Japan; Russia
Abstract:
... It is widely accepted that subduction of the Paleo-Pacific Plate beneath Eurasia began in the early Mesozoic. However, the tectonic nature and processes of the NE Asian continental margin in the Late Jurassic to early Early Cretaceous remain unclear. In this contribution, lithological, provenance, and metamorphic–deformation data are used to constrain the formation of Mesozoic accretionary complex ...
DOI:
10.1016/j.earscirev.2019.103042

96. Linking heterogeneous distribution of radiocaesium in soils and pond sediments in the Fukushima Daiichi exclusion zone to mobility and potential bioavailability

Author:
Estela Reinoso-Maset; Justin Brown; Marit N. Pettersen; Frits Steenhuisen; Abednego Tetteh; Toshihiro Wada; Thomas G. Hinton; Brit Salbu; Ole Christian Lind
Source:
Journal of environmental radioactivity 2020 v.211 pp. 106080
ISSN:
0265-931X
Subject:
accidents; air; autoradiography; bioavailability; cesium; computer software; environmental impact; gamma spectrometry; gastric juice; leaching; nuclear power; power plants; radioactivity; radionuclides; sediments; soil; Japan
Abstract:
... During the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 significant amounts of radiocaesium were released into the atmosphere from the reactor units 1, 2 and 3. This caused a non-uniform deposition, in composition and direction, of ¹³⁴Cs and ¹³⁷Cs in the near field (<30 km) from the reactors. In this work, we elucidate the influence of speciation, including radioactive particles, ...
DOI:
10.1016/j.jenvrad.2019.106080

97. Major element and REE compositions of Pliocene sediments in southwest Japan: Implications for paleoweathering and paleoclimate

Author:
Nozomi Hatano; Kohki Yoshida; Saori Mori; Eiji Sasao
Source:
Sedimentary geology 2020 v.408 pp. 105751
ISSN:
0037-0738
Subject:
Pleistocene epoch; Pliocene epoch; clay; coasts; humid zones; monsoon season; paleoclimatology; rare earth elements; sediments; summer; tectonics; weathering; Japan
Abstract:
... The history of the East Asian monsoon and the relationship between the development of the monsoon climate, tectonics and global climate are complicated and controversial. Earlier studies have indicated that the East Asian monsoon fluctuated in the Asian interior during the Pliocene. Thus, the chemical weathering record in coastal regions of East Asia can be the key to elucidating its evolution as ...
DOI:
10.1016/j.sedgeo.2020.105751

98. Mass balance and latest fluxes of radiocesium derived from the fukushima accident in the western North Pacific Ocean and coastal regions of Japan

Author:
Michio Aoyama; Daisuke Tsumune; Yayoi Inomata; Yutaka Tateda
Source:
Journal of environmental radioactivity 2020 v.217 pp. 106206
ISSN:
0265-931X
Subject:
accidents; atmospheric deposition; cesium radioisotopes; coasts; decontamination; inventories; radioactivity; rivers; sediments; soil; Japan; Pacific Ocean; Sea of Japan
Abstract:
... This article summarizes and discusses mass balance calculations of the activities of Fukushima-derived ¹³⁷Cs released to the atmosphere and ocean prior to 2018 as well as the ¹³⁷Cs inventories on land and in the ocean, biota, and sediment. We propose that the consensus value of the total amount of ¹³⁷Cs released to the atmosphere was 15–21 PBq; atmospheric deposition of ¹³⁷Cs on land was 3–6 PBq; ...
DOI:
10.1016/j.jenvrad.2020.106206

99. Mercury speciation in preserved historical sludge: Potential risk from sludge contained within reclaimed land of Minamata Bay, Japan

Author:
Mineshi Sakamoto; Takaaki Itai; Kohji Marumoto; Masumi Marumoto; Hitoshi Kodamatani; Takashi Tomiyasu; Hiromitsu Nagasaka; Keisuke Mori; Alexandre J. Poulain; José L. Domingo; Milena Horvat; Akito Matsuyama
Source:
Environmental research 2020 v.180 pp. 108668
ISSN:
0013-9351
Subject:
X-ray absorption spectroscopy; dredging; energy-dispersive X-ray analysis; fish; mercury; mercury poisoning; methylmercury compounds; reclaimed land; remediation; risk; seawater; sediments; shellfish; sludge; transmission electron microscopy; wastewater; Japan
Abstract:
... In the latter half of the 1950s, a large amount of methylmercury (MeHg) was discharged directly into Minamata Bay, Japan by a chemical factory, resulting in the contamination of the fish and shellfish. Ultimately, an outbreak of MeHg intoxication, called Minamata disease, occurred. From 1977 to 1988, the Kumamoto Prefectural Government dredged and transferred sediments exceeding 25 μg/g of total m ...
DOI:
10.1016/j.envres.2019.108668

100. Metal partitioning and leaching vulnerability in soil, soakaway sediments, and road dust in the urban area of Japan

Author:
Manish Kumar; Hiroaki Furumai; Ikuro Kasuga; Futoshi Kurisu
Source:
Chemosphere 2020 v.252 pp. 126605
ISSN:
0045-6535
Subject:
cadmium; compliance; copper; dust; environmental factors; groundwater; isotope dilution technique; leaching; lead; models; prediction; sediment deposition; sediments; soil; sorption; urban areas; zinc; Japan
Abstract:
... Isotope dilution techniques (IDT) and sequential extraction procedures (SEPs) were compared to apprehend the differences between two techniques in determining metal exchangeability and vulnerability to pollute the urban groundwater. For this purpose, soil (n = 2), “soakaway” sediment deposited in the artificial infiltration facilities (AIF) (n = 4), and road dust (n = 2) were sampled from Tokyo me ...
DOI:
10.1016/j.chemosphere.2020.126605