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1. Adaptive downsizing in the piscivorous cyprinid fish, Opsariichthys uncirostris, facilitates rapid establishment after introduction to a small-scale habitat in Japan

Author:
Kei’ichiro Iguchi; Yuta Matsumoto; Yoshihisa Kurita; Katsutoshi Watanabe
Source:
Biological invasions 2019 v.21 no.6 pp. 2059-2066
ISSN:
1387-3547
Subject:
Opsariichthys uncirostris; body size; ecological invasion; evolutionary adaptation; eyes; fish; food availability; habitats; head; irrigation canals; lakes; morphometry; phenotypic plasticity; piscivores; principal component analysis; rivers; sexual maturity; swimming; tail; Japan
Abstract:
... The three-lips (Opsariichthys uncirostris) is a piscivorous cyprinid fish native to the Biwa Lake, central Japan. A recent unintentional introduction of the species has led to its invasion of a novel, small-scale habitat (the Futatsu River) composed of a few riverine stretches connected by irrigation ditches. Comparative observations of fish samples from both habitats provide evidence of dispariti ...
DOI:
10.1007/s10530-019-01957-3

2. Anthropogenic impacts on the distribution of wild and cultured Japanese eels in the Tone River watershed, Japan, from otolith oxygen and carbon stable isotopic composition

Author:
Kohma Arai; Hikaru Itakura; Akihito Yoneta; Kenzo Kaifu; Kotaro Shirai; Yoichi Miyake; Shingo Kimura
Source:
Environmental biology of fishes 2019 v.102 no.11 pp. 1405-1420
ISSN:
0378-1909
Subject:
Anguilla japonica; anthropogenic activities; carbon; eel; farmed fish; fish culture; fisheries; gates; models; otoliths; oxygen; resource management; rivers; stable isotopes; watersheds; Japan
Abstract:
... Effective management decisions are vital for the declining Japanese eel Anguilla japonica. Elucidating the distribution range of wild eels (i.e., naturally recruited individuals) represents the first step in resource management, although stocking of cultured eels throughout the waters of Japan masks the original distribution range of wild eels. Herein, we applied a recently developed discriminatio ...
DOI:
10.1007/s10641-019-00915-1

3. Assessing alpha and beta diversities of benthic macroinvertebrates and their environmental drivers between watersheds with different levels of habitat transformation in Japan

Author:
Chia-Ying Ko; Tomoya Iwata; Jun-Yi Lee; Aya Murakami; Junichi Okano; Naoto F. Ishikawa; Yoichiro Sakai; Ichiro Tayasu; Masayuki Itoh; Uhram Song; Hiroyuki Togashi; Shinich Nakano; Nobuhito Ohte; Noboru Okuda
Source:
Marine & freshwater research 2019 v.70 no.4 pp. 504-512
ISSN:
1323-1650
Subject:
chlorophyll; ecological communities; environmental factors; freshwater; freshwater ecosystems; habitat destruction; habitats; macroinvertebrates; planning; rivers; species diversity; water temperature; watersheds; Japan
Abstract:
... Little is known about differences in species diversity among ecological communities subject to different levels of human-caused habitat transformation and how this disturbance contributes to diversity through symbiotic dependencies with the environment in freshwater ecosystems. We estimated α and β diversities of benthic macroinvertebrates and relationships between diversity and environmental vari ...
DOI:
10.1071/MF18031

4. Assessment of organophosphorus flame retardants and plasticizers in aquatic environments of China (Pearl River Delta, South China Sea, Yellow River Estuary) and Japan (Tokyo Bay)

Author:
Nelson L.S. Lai; Karen Y. Kwok; Xin-hong Wang; Nobuyoshi Yamashita; Guijian Liu; Kenneth M.Y. Leung; Paul K.S. Lam; James C.W. Lam
Source:
Journal of hazardous materials 2019 v.371 pp. 288-294
ISSN:
0304-3894
Subject:
aquatic environment; aquatic organisms; carcinogens; cities; coasts; estuaries; flame retardants; gross domestic product; manufacturing; phosphates; plasticizers; river deltas; rivers; socioeconomic development; China; Japan; South China Sea; Yellow River
Abstract:
... The concentrations and spatial distribution of 14 organophosphorus flame retardants (OPFRs) and plasticizers were studied in aquatic environments of China, namely, the Pearl River Delta (PRD), South China Sea (SCS) and Yellow River Estuary (YRE), as well as Tokyo Bay (TB) in Japan. These locations were characterized by different levels of socioeconomic development and human activities. The spatial ...
DOI:
10.1016/j.jhazmat.2019.03.029

5. Assessment of the sources and inflow processes of microplastics in the river environments of Japan

Author:
Tomoya Kataoka; Yasuo Nihei; Kouki Kudou; Hirofumi Hinata
Source:
Environmental pollution 2019 v.244 pp. 958-965
ISSN:
0269-7491
Subject:
basins; biochemical oxygen demand; environmental indicators; humans; microplastics; models; pH; pollutants; population density; rivers; total nitrogen; total phosphorus; urbanization; waste management; water quality; watersheds; Japan
Abstract:
... The numerical and mass concentrations of microplastics collected at 36 sites on the surfaces of 29 Japanese rivers were mapped and compared with four basin characteristics (basin area, population density, and urban and agricultural ratios) and six water quality parameters (pH, biochemical oxygen demand (BOD), suspended solids (SS), dissolved oxygen (DO), total nitrogen (T-N), and total phosphorus ...
DOI:
10.1016/j.envpol.2018.10.111

6. Associations of Community Structure and Functions of Benthic Invertebrates with Nickel Concentrations: Analyses from Field Surveys

Author:
Kazutaka M. Takeshita; Takahiro Misaki; Takehiko I. Hayashi; Hiroyuki Yokomizo
Source:
Environmental toxicology and chemistry 2019 v.38 no.8 pp. 1728-1737
ISSN:
0730-7268
Subject:
Ephemeroptera; European Union; Plecoptera; Trichoptera; aquatic organisms; biomass; community structure; ecosystems; environmental quality; heavy metals; invertebrates; nickel; predators; regression analysis; rivers; surveys; uncertainty; Japan
Abstract:
... Field surveys provide valuable empirical information about the effects of heavy metals on the biological integrity of river ecosystems. To evaluate the effect of nickel (Ni) on aquatic organisms, we conducted field surveys of benthic invertebrates and Ni concentrations at 45 sites in 19 rivers in Japan. We examined the relationships between 11 structural or functional measures of benthic invertebr ...
DOI:
10.1002/etc.4462

7. Big in Japan: The importance of riparian corridors for Orthoptera

Author:
Tim Gardiner; Noburo Kuramoto; Misako Matsuba
Source:
Journal of orthoptera research 2019 v.28 no.1 pp. 27-35
ISSN:
1937-2426
Subject:
Asteraceae; Orthoptera; endangered species; fauna; floodplains; forests; grasshoppers; gravel; infrastructure; invasive species; land use; mowing; paddies; plants (botany); riparian areas; rivers; terraces; Japan
Abstract:
... There are few studies on the Orthoptera of the floodplains, paddy fields, and levee embankments of Japan’s riparian corridors. The research which has been undertaken indicates a relatively rich fauna (33% of Japan’s grasshopper species recorded) with endangered species (e.g. Eusphingonotusjaponicus) found on gravel floodplains, although diversity is restricted by forest cover and unfavorable land ...
DOI:
10.3897/jor.28.31380

8. Concordance between molecular biogeography of Dipteromimus tipuliformis and geological history in the local fine scale (Ephemeroptera, Dipteromimidae)

Author:
Masaki Takenaka; Tetsuya Tokiwa; Koji Tojo
Source:
Molecular phylogenetics and evolution 2019 v.139 pp. 106547
ISSN:
1055-7903
Subject:
Ephemeroptera; Quaternary period; biodiversity; environmental factors; gene flow; genetic variation; geographical distribution; histones; indigenous species; islands; mitochondrial DNA; mountains; nuclear genome; phylogeny; ribosomal DNA; ribosomal RNA; rivers; species dispersal; tectonics; Japan
Abstract:
... Species distribution area is determined by both biotic and abiotic factors. In particular, significant geological events influence the biodiversity and the genetic structures of the organisms inhabiting the area. The establishment of physical barriers (e.g., mountains, rivers), drives species differentiation by their interference with biological dispersal or gene flow. The Japanese Islands have a ...
DOI:
10.1016/j.ympev.2019.106547

9. Cyt b gene and D-loop sequence analyses of Coilia nasus from the Rokkaku River of Japan

Author:
Chao Sun; Zhongya Xuan; Hongbo Liu; Tao Jiang; Jian Yang
Source:
Regional studies in marine science 2019 v.32 pp. 100840
ISSN:
2352-4855
Subject:
Coilia mystus; Coilia nasus; anadromous fish; anchovies; estuaries; genes; genetic distance; genetic variation; haplotypes; marine science; monophyly; population dynamics; rivers; sequence analysis; China; Japan
Abstract:
... The estuarine tapertail anchovy (Coilia nasus) is a small anadromous fish mainly distributed in the northwest and western Pacific, extending southward toward Guangdong in southeastern China and northward to the Ariake Sound of southwestern Japan. This important commercial anchovy has suffered from population decline in both Japan and China, and the taxonomic status of the populations from Japan an ...
DOI:
10.1016/j.rsma.2019.100840

10. Dissolved 137Cs concentrations in stream water and subsurface water in a forested headwater catchment after the Fukushima Dai-ichi Nuclear Power Plant accident

Author:
Sho Iwagami; Maki Tsujimura; Yuichi Onda; Ryohei Konuma; Yutaro Satou; Koichi Sakakibara; Vasyl Yoschenko
Source:
Journal of hydrology 2019 v.573 pp. 688-696
ISSN:
0022-1694
Subject:
accidents; base flow; cesium; groundwater; leachates; nuclear power; power plants; radionuclides; rivers; soil water; streams; summer; watersheds; Japan
Abstract:
... Numerous studies have been conducted on ¹³⁷Cs transport in the environment in Fukushima, Japan, since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. Many studies have monitored river and stream water, and a declining trend in dissolved ¹³⁷Cs concentrations has been reported. In addition, temporary increases in dissolved ¹³⁷Cs concentrations have been observed during rainstorm events. ...
DOI:
10.1016/j.jhydrol.2019.04.019

11. Downstream migration and mortality of larval Ayu (Plecoglossus altivelis altivelis) on the Sanriku coast, northern Japan

Author:
Masayoshi Hata; Tsuguo Otake
Source:
Environmental biology of fishes 2019 v.102 no.10 pp. 1311-1325
ISSN:
0378-1909
Subject:
Plecoglossus altivelis; coasts; larvae; mortality; rivers; spawning; surveys; Japan
Abstract:
... The ecology and mortality of larval ayu (Plecoglossus altivelis altivelis) during downstream migration was investigated during three spawning seasons (2008–2010) in the Unosumai River, Iwate Prefecture, Japan. Downstream larval migration occurred from early September to mid-December, peaking from late September to mid-October. Larval drift numbers recorded at the lowest reach spawning ground peake ...
DOI:
10.1007/s10641-019-00909-z

12. Ecological risks of insecticide contamination in water and sediment around off-farm irrigated rice paddy fields

Author:
Shunsuke Furihata; Atsushi Kasai; Kazumasa Hidaka; Makihiko Ikegami; Hitoshi Ohnishi; Koichi Goka
Source:
Environmental pollution 2019 v.251 pp. 628-638
ISSN:
0269-7491
Subject:
acute toxicity; aquatic organisms; biodiversity; dinotefuran; environmental assessment; environmental impact; fipronil; irrigation; paddies; pesticide application; risk; risk assessment; rivers; sediments; surface water; Japan
Abstract:
... The ecological impacts of insecticides in aquatic areas around agricultural lands have long been ignored in the regulation scheme of pesticides in Japan. Upon the scheme, the predicted concentration of an insecticide in the main stream of a river is the only parameter considered, suggesting that the ecological impacts of insecticides on local biodiversity around agricultural fields are underestima ...
DOI:
10.1016/j.envpol.2019.05.009

13. Effect of neap-spring hydrodynamics on salt and suspended sediment transport in multi-branched urban estuaries

Author:
Joan Cecilia Casila; Victor Ella; Katsuhide Yokoyama
Source:
Science of the total environment 2019 v.694 pp. 133653
ISSN:
0048-9697
Subject:
combined sewer systems; dissolved oxygen; estuaries; freshwater; hydrodynamics; hypoxia; nutrients; odors; oxygen; particulate organic matter; rivers; salinity; sediment transport; sediments; suspended sediment; tides; turbidity; water quality; Japan
Abstract:
... Unique neap and spring tide hydrodynamic features were studied in the estuarine areas of multi-branched urban rivers in Tokyo, Japan. Intensive measurements of salinity, turbidity, dissolved oxygen, velocity, particulate organic matter (POM), and nutrients were conducted for 13h in five stations simultaneously on July 3 and July 11, 2017. Water sampling, analysis and calculations of salt and sedim ...
DOI:
10.1016/j.scitotenv.2019.133653

14. Evaluation from otolith Sr stable isotope ratios of possible juvenile growth areas of Japanese eels collected from the West Mariana Ridge spawning area

Author:
Tsuguo Otake; Yosuke Amano; Kotaro Shirai; Noritaka Mochioka; Toshiro Takahashi; Seinen Chow; Hiroaki Kurogi; Shouzeng Dou; Asuka Yamaguchi; Katsumi Tsukamoto
Source:
Fisheries science 2019 v.85 no.3 pp. 483-493
ISSN:
0919-9268
Subject:
Anguilla japonica; adults; eel; estuaries; genetic similarity; habitat preferences; juveniles; otoliths; rivers; seawater; spawning; stable isotopes; strontium; China; Japan; Korean Peninsula; Taiwan
Abstract:
... The widely distributed East Asian Japanese eel Anguilla japonica constitutes a single genetically homogeneous population with a single spawning area near the West Mariana Ridge. Otolith ⁸⁷Sr/⁸⁶Sr ratios of adults (categorized as “river“, “estuarine” or “sea” eels, according to their habitat use history determined from otolith Sr:Ca ratio analysis) collected from the spawning area in 2008 and 2009 ...
DOI:
10.1007/s12562-019-01304-4

15. Evaluation of Human- and Animal-Specific Viral Markers and Application of CrAssphage, Pepper Mild Mottle Virus, and Tobacco Mosaic Virus as Potential Fecal Pollution Markers to River Water in Japan

Author:
Bikash Malla; Koki Makise; Koki Nakaya; Taizo Mochizuki; Takahiro Yamada; Eiji Haramoto
Source:
Food and environmental virology 2019 v.11 no.4 pp. 446-452
ISSN:
1867-0334
Subject:
Pepper mild mottle virus; Tobacco mosaic virus; humans; river water; rivers; swine; water pollution; Japan
Abstract:
... Five human-specific markers were detected in 59–74% of 27 human fecal-source samples collected in Yamanashi Prefecture, Japan. Similarly, potential human-specific markers, crAssphage, pepper mild mottle virus (PMMoV), and tobacco mosaic virus were detected in 96–100% of samples, with crAssphage showing the maximum concentration of 12.03 log copies/L. However, these markers were detected in 100% (3 ...
DOI:
10.1007/s12560-019-09398-w

16. Evaluation of the effects of irrigation water on groundwater budget by a hydrologic model

Author:
Keiji Takase; Yoichi Fujihara
Source:
Paddy and water environment 2019 v.17 no.3 pp. 439-446
ISSN:
1611-2490
Subject:
aquifers; coasts; groundwater; hydrologic cycle; hydrologic models; irrigation; irrigation water; paddies; rain; river water; rivers; saltwater intrusion; seepage; water table; Japan
Abstract:
... Groundwater is a valuable water resource, and it is used for domestic, industrial or agricultural use around the world. Especially, water use in paddy fields is very large, and it influences groundwater in Japan. However, it is difficult to understand its water balance and to control it for management, because it flows under the ground and is affected by a lot of processes in the hydrologic cycle. ...
DOI:
10.1007/s10333-019-00739-w

17. Factors controlling dissolved 137Cs concentrations in east Japanese Rivers

Author:
Hideki Tsuji; Yumiko Ishii; Moono Shin; Keisuke Taniguchi; Hirotsugu Arai; Momo Kurihara; Tetsuo Yasutaka; Takayuki Kuramoto; Takahiro Nakanishi; Sangyoon Lee; Takuro Shinano; Yuichi Onda; Seiji Hayashi
Source:
Science of the total environment 2019 v.697 pp. 134093
ISSN:
0048-9697
Subject:
absorption; accidents; cesium; dissolved organic carbon; equations; hydrologic models; inventories; land use; nuclear power; organic soils; potassium; power plants; radionuclides; regression analysis; river water; rivers; soil composition; solutes; topography; urban areas; water quality; watersheds; wetlands; Japan
Abstract:
... To investigate the main factors that control the dissolved radiocesium concentration in river water in the area affected by the Fukushima Daiichi nuclear power plant accident, the correlations between the dissolved ¹³⁷Cs concentrations at 66 sites normalized to the average ¹³⁷Cs inventories for the watersheds with the land use, soil components, topography, and water quality factors were assessed. ...
DOI:
10.1016/j.scitotenv.2019.134093

18. Flood Simulations in Mid-Latitude Agricultural Land Using Regional Current and Future Extreme Weathers

Author:
Nobuaki Kimura; Hirohide Kiri; Sachie Kanada; Iwao Kitagawa; Ikuo Yoshinaga; Hidenori Aiki
Source:
Water 2019 v.11 no.11 pp. -
ISSN:
2073-4441
Subject:
agricultural land; climate; climate models; hydrologic models; latitude; meteorological data; riparian areas; risk; rivers; simulation models; typhoons; watersheds; Japan
Abstract:
... Recent extreme weather events like the August 2016 flood disaster have significantly affected farmland in mid-latitude regions like the Tokachi River (TR) watershed, the most productive farmland in Japan. The August 2016 flood disaster was caused by multiple typhoons that occurred in the span of two weeks and dealt catastrophic damage to agricultural land. This disaster was the focus of our flood ...
DOI:
10.3390/w11112421

19. Genetic population structure of Japanese river sculpin Cottus pollux (Cottidae) large‐egg type, inferred from mitochondrial DNA sequences

Author:
Shoichiro Yamamoto
Source:
Journal of fish biology 2019 v.94 no.2 pp. 325-329
ISSN:
0022-1112
Subject:
Cottus pollux; Japan; fish; genetic structure; geographical distribution; haplotypes; mitochondrial DNA; population genetics; population structure; rivers
Abstract:
... The geographic distribution of mitochondrial DNA haplotypes from Japanese river sculpin Cottus pollux large‐egg type (LE), collected from 55 locations in 22 rivers over most of the species’ range in Japan, was examined to assess for patterns of population genetic structure. The 87 haplotypes observed from C. pollux LE were distinguishable from C. pollux middle‐egg type and small‐egg type haplotype ...
DOI:
10.1111/jfb.13890

20. Genetic relatedness of Mycobacterium avium subsp. hominissuis isolates from bathrooms of healthy volunteers, rivers, and soils in Japan with human clinical isolates from different geographical areas

Author:
Kentaro Arikawa; Tomoaki Ichijo; Satomi Nakajima; Yukiko Nishiuchi; Hirokazu Yano; Aki Tamaru; Shiomi Yoshida; Fumito Maruyama; Atsushi Ota; Masao Nasu; Daria A. Starkova; Igor Mokrousov; Olga V. Narvskaya; Tomotada Iwamoto
Source:
Infection, genetics, and evolution 2019 v.74 pp. 103923
ISSN:
1567-1348
Subject:
Mycobacterium avium; genetic relationships; genetic variation; humans; lifestyle; minisatellite repeats; pathogens; patients; respiratory tract diseases; river water; rivers; soil; swine; tandem repeat sequences; volunteers; Japan
Abstract:
... Japan reportedly has high incidence rate of nontuberculous mycobacterial lung disease (14.7 cases per 100,000 person in 2014). In Japan, the most common etiology is Mycobacterium avium subsp. hominissuis (MAH). MAH is a typical inhabitant of the environment, especially bathrooms, which are considered as a potential source of infection. To corroborate this hypothesis, we determined the detection ra ...
DOI:
10.1016/j.meegid.2019.103923

21. How Does the Japanese Water Shrew Chimarrogale platycephalus Cross the Concrete Walls of Check Dams?

Author:
Hiroaki Saito; Hiroshi Hashimoto; Teruaki Hino; Masaharu Motokawa
Source:
Mammal study 2019 v.44 no.1 pp. 1-11
ISSN:
1348-6160
Subject:
concrete; dams (hydrology); rivers; sediments; shrews; streams; surveys; Japan
Abstract:
... The concrete walls of check dams are considered a physical barrier for aquatic and semiaquatic animals that inhabit mountain streams. Traveling behaviors around concrete check dams by the Japanese water shrew Chimarrogale platycephalus, a semi-aquatic mammal, were directly observed via radio-tracking in Kamikoshi Stream in central Honshu, Japan. Traveling behaviors were mainly observed on the wet ...
DOI:
10.3106/ms2017-0056

22. Identification of Phosphorus Sources in a Watershed Using a Phosphate Oxygen Isoscape Approach

Author:
Takuya Ishida; Yoshitoshi Uehara; Tomoya Iwata; Abigail P. Cid-Andres; Satoshi Asano; Tohru Ikeya; Ken’ichi Osaka; Jun’ichiro Ide; Osbert Leo A. Privaldos; Irisse Bianca B. De Jesus; Elfritzson M. Peralta; Ellis Mika C. Triño; Chia-Ying Ko; Adina Paytan; Ichiro Tayasu; Noboru Okuda
Source:
Environmental science & technology 2019 v.53 no.9 pp. 4707-4716
ISSN:
1520-5851
Subject:
bedrock; ecosystems; eutrophication; hydrologic models; land use; oxygen; oxygen isotopes; paddies; phosphates; phosphorus; pollution load; river water; rivers; watersheds; Japan
Abstract:
... Identifying nonpoint phosphorus (P) sources in a watershed is essential for addressing cultural eutrophication and for proposing best-management solutions. The oxygen isotope ratio of phosphate (δ¹⁸OPO₄) can shed light on P sources and P cycling in ecosystems. This is the first assessment of the δ¹⁸OPO₄ distribution in a whole catchment, namely, the Yasu River Watershed in Japan. The observed δ¹⁸O ...
DOI:
10.1021/acs.est.8b05837

23. Interannual changes in radiocesium concentrations in annually laminated tufa following the Fukushima Daiichi Nuclear Power Plant accident

Author:
Nagayoshi Katsuta; Yoshiki Miyata; Takuma Murakami; Yoshihisa Mino; Sayuri Naito; Koji Yasuda; Shinya Ochiai; Osamu Abe; Atsushi Yasuda; Maki Morimoto; Shin-ichi Kawakami; Seiya Nagao
Source:
Applied geochemistry 2019 v.102 pp. 34-43
ISSN:
0883-2927
Subject:
Andosols; accidents; calcite; carbonates; cesium; dissolved carbon dioxide; geochemistry; mica; nuclear power; power plants; radionuclides; rain; river water; rivers; seasonal variation; stream channels; summer; temperature; texture; Japan
Abstract:
... Chemical and radiocesium concentrations in water and riverbed tufa of the Nigori River, flowing out of the southern foot of Mt. Asama volcano in central Japan, were investigated following the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. This tufa is characterized by porous and dense laminae. Its annual lamination (varve) is formed by seasonal changes in dissolved CO2 concentration in wa ...
DOI:
10.1016/j.apgeochem.2019.01.002

24. Introduction of DEAE Sepharose for isolation of dissolved organic matter

Author:
Morimaru Kida; Hajime Sato; Asuka Okumura; Haruka Igarashi; Nobuhide Fujitake
Source:
Limnology 2019 v.20 no.2 pp. 153-162
ISSN:
1439-8621
Subject:
adsorption; agarose; anion exchange resins; cellulose; dissolved organic carbon; fulvic acids; lakes; models; nuclear magnetic resonance spectroscopy; rivers; Japan
Abstract:
... An anion exchange resin, diethylaminoethyl (DEAE) Sepharose®, was utilized for the isolation of dissolved organic matter (DOM) from fresh waters as an alternative to the discontinued DEAE cellulose. We used the following two chemically distinct model DOM samples to determine the optimized adsorption conditions onto DEAE Sepharose: the International Humic Substances Society’s standard samples, Suwa ...
DOI:
10.1007/s10201-018-0561-3

25. Longitudinal and microhabitat distributions of fishes, amphibians, and reptiles and the environmental characteristics in the upper Yura River, Kyoto, Japan

Author:
Hikaru Nakagawa
Source:
Ecological research 2019 v.34 no.2 pp. 245
ISSN:
0912-3814
Subject:
Japan; amphibians; data collection; fish; habitat preferences; microhabitats; reptiles; research; rivers; streams; sympatry; vegetation cover
Abstract:
... Quantitative data on the distribution of aquatic vertebrate species along environmental gradients at multiple spatial scales are useful for assessing habitat quality, understanding habitat selection, and predicting the population structures of focal species. In addition, comparable datasets for multiple species enable the examination of the interspecific differences in habitat niches and their dif ...
DOI:
10.1111/1440-1703.1268

26. Longitudinal distribution and microhabitat use of young Japanese eel Anguilla japonica in a small river flowing through paddy areas

Author:
Manabu Kume; Yuki Terashima; Toshihiro Wada; Yoh Yamashita
Source:
Journal of applied ichthyology 2019 v.35 no.4 pp. 876-883
ISSN:
0175-8659
Subject:
Anguilla japonica; eel; habitat preferences; linear models; microhabitats; paddies; rivers; stream channels; weirs; Japan
Abstract:
... Although the Japanese eel Anguilla japonica is a commercially important species, its habitat use is not well understood during its life stages in the river. In this study, we investigated the longitudinal distribution and microhabitat use of young Japanese eels (<200 mm in total length [TL], which correspond to elver and early yellow stages) using 180 quadrates (1 m × 1 m) in six stations in a sma ...
DOI:
10.1111/jai.13911

27. Long‐term fauna and flora records of the experimental forests of the Forest Research Station of Hokkaido University, Japan

Author:
Chisato Terada; TaeOh Kwon; Nobuko Kazahari; Osamu Kishida; Shunsuke Utsumi
Source:
Ecological research 2019 v.34 no.3 pp. 349
ISSN:
0912-3814
Subject:
Japan; biodiversity; databases; fauna; flora; research; rivers; surveys; vascular plants; vegetation structure; vertebrates
Abstract:
... The Forest Research Station of Hokkaido University owns a vast area of experimental forests, which are composed of a large variety of ecosystems ranging from aquatic ecosystems, such as wetlands and river basins, to various types of forests, such as primary, secondary and artificial forests. Additionally, these forests are representative of numerous climatic zones, such as warm temperate, cool tem ...
DOI:
10.1111/1440-1703.12007

28. Modern lake ecosystem management by sustainable harvesting and effective utilization of aquatic macrophytes

Author:
Syuhei Ban; Tatsuki Toda; Mitsuhiko Koyama; Kanako Ishikawa; Ayato Kohzu; Akio Imai
Source:
Limnology 2019 v.20 no.1 pp. 93-100
ISSN:
1439-8621
Subject:
anaerobic digestion; aquatic ecosystems; ecosystem management; harvesting; lakes; littoral zone; macrophytes; microalgae; mineral fertilizers; plant growth; rivers; Japan
Abstract:
... There are many problems related to overgrowth of aquatic macrophytes in many lakes and rivers throughout the world; for instance, the harvesting costs in Lake Biwa have been increasing by 200 million Japanese yen a year (equivalent to 1.8 million USD). Historically, aquatic macrophytes were harvested for use as fertilizer in agriculture in Japan, but are no longer in use because chemical fertilize ...
DOI:
10.1007/s10201-018-0557-z

29. Morphological Changes of the Lower Tedori River, Japan, over 50 Years

Author:
Dang Minh Hai; Shinya Umeda; Masatoshi Yuhi
Source:
Water 2019 v.11 no.9 pp. -
ISSN:
2073-4441
Subject:
aerial photography; anthropogenic activities; dams (hydrology); data collection; empirical models; rivers; sediments; spatial variation; surveys; temporal variation; topography; watersheds; Japan
Abstract:
... Long-term variation in the morphological characteristics of rivers is complicated as a result of temporally and spatially variable natural processes and anthropogenic disturbances. Better understanding of their relationship is therefore important for river basin management. The present study conducted a detailed analysis of a long-term dataset consisting of a 58-year topographic survey and related ...
DOI:
10.3390/w11091852

30. Multiple habitat use of Japanese sea bass Lateolabrax japonicus in the estuary region of the Tone River system, implied by stable isotope analysis

Author:
Yoichi Miyake; Hikaru Itakura; Aigo Takeshige; Hiroaki Onda; Akira Yamaguchi; Akihito Yoneta; Kohma Arai; Yulina V. Hane; Shingo Kimura
Source:
Ichthyological research 2019 v.66 no.1 pp. 172-176
ISSN:
1341-8998
Subject:
Lateolabrax japonicus; carbon; estuaries; euryhaline species; fish; habitat preferences; muscle tissues; nitrogen; rivers; saline water; stable isotopes; winter; Japan
Abstract:
... Japanese sea bass Lateolabrax japonicus is a euryhaline fish species. The present study aimed to elucidate their habitat use in the estuary region of the Tone River system in Japan through stable isotope analysis. Carbon and nitrogen stable isotope ratios of muscle tissues of 74 specimens were grouped by hierarchical cluster analysis and were compared with body sizes. The results suggested that Ja ...
DOI:
10.1007/s10228-018-0655-2

31. Numerical and experimental study on the risk of paddy field damage due to river bank breach during serious floods

Author:
Tetsuro Tsujimoto; Kumiko Tsujimoto
Source:
Paddy and water environment 2019 v.17 no.2 pp. 247-253
ISSN:
1611-2490
Subject:
Oryza sativa; climate change; disasters; floods; laboratory experimentation; land use; landscapes; paddies; ponds; rain; residential areas; rice; rivers; rural areas; sediment transport; sediments; soil; Japan
Abstract:
... In Japan, paddy fields located adjacent to rivers are a familiar landscape in rural areas, and they are divided from rivers by soil banks. Soil banks are easily breached by overtopping in floods. Previously, although soil banks were often breached in many locations, inundation in paddy fields was not necessarily a serious disaster, but it was rather positively accepted as a nutrient supplier to pa ...
DOI:
10.1007/s10333-019-00717-2

32. Post-release behaviors and movements of cultured and wild Japanese eels (Anguilla japonica) in a shallow brackish water lagoon in northeastern Japan

Author:
Takuji Noda; Toshihiro Wada; Takashi Iwasaki; Tatsuma Sato; Kaoru Narita; Ikuo Matsumoto; Tomoya Hori; Hiromichi Mitamura; Nobuaki Arai
Source:
Environmental biology of fishes 2019 v.102 no.12 pp. 1435-1456
ISSN:
0378-1909
Subject:
Anguilla japonica; acoustics; brackish water; eel; farmed fish; nocturnal activity; reproduction; rivers; typhoons; water temperature; Japan
Abstract:
... A total of 30 cultured [610.6 ± 24.0 mm total length (TL)] and six wild Japanese eels Anguilla japonica collected on site (622.2 ± 133.1 mm TL) were tagged with acoustic transmitters and released into a shallow brackish water lagoon in northeastern Japan in June 2014 and July–October 2014, respectively; their post-release movements in the entire lagoon were monitored by acoustic receivers. We foun ...
DOI:
10.1007/s10641-019-00917-z

33. The Role of the Spatial Distribution of Radar Rainfall on Hydrological Modeling for an Urbanized River Basin in Japan

Author:
Shakti P. C.; Tsuyoshi Nakatani; Ryohei Misumi
Source:
Water 2019 v.11 no.8 pp. -
ISSN:
2073-4441
Subject:
basins; hydrologic engineering; hydrologic models; meteorological data; polarimetry; radar; rain; rivers; runoff; statistical analysis; urbanization; watersheds; Japan
Abstract:
... Recently, the use of gridded rainfall data with high spatial resolutions in hydrological applications has greatly increased. Various types of radar rainfall data with varying spatial resolutions are available in different countries worldwide. As a result of the variety in spatial resolutions of available radar rainfall data, the hydrological community faces the challenge of selecting radar rainfal ...
DOI:
10.3390/w11081703

34. Soil carbon stocks and their primary origin at mature mangrove ecosystems in the estuary of Fukido River, Ishigaki Island, southwestern Japan

Author:
Yasuo Iimura; Kazutoshi Kinjo; Miyuki Kondo; Toshiyuki Ohtsuka
Source:
Soil science and plant nutrition 2019 v.65 no.5 pp. 435-443
ISSN:
1747-0765
Subject:
Bruguiera gymnorhiza; Rhizophora stylosa; aboveground biomass; carbon; carbon sinks; estuaries; fine roots; leaves; mangrove forests; rivers; soil; soil carbon; stable isotopes; subtropics; trees; tropics; Japan
Abstract:
... Mangrove ecosystems play an important role in carbon (C) accumulation in tropical and subtropical regions. Below-ground deep anoxic soil is especially important for C accumulation. However, quantitative data on below-ground soil C stocks in mangrove ecosystems are lacking compared with data on above-ground biomass. In addition, soil C accumulation processes in mangrove ecosystems have not been suf ...
DOI:
10.1080/00380768.2019.1660589

35. Spatial distribution of spawning redds and larvae of Rhinogobius flumineus in relation to hydrogeomorphological characteristics in Kamo River, Japan

Author:
Kohei Yokota; Yasuhiro Takemon; Masayuki Fujihara
Source:
Paddy and water environment 2019 v.17 no.3 pp. 475-483
ISSN:
1611-2490
Subject:
Rhinogobius flumineus; aquatic insects; dominant species; egg masses; freshwater; habitats; larvae; predation; predatory fish; rivers; spawning; statistical models; stream channels; vegetation; Japan
Abstract:
... A freshwater goby, Rhinogobius flumineus, is one of the dominant species in the Kamo River and the Takano River, Kyoto City, Japan. We investigated the spatial distribution of their spawning redds and larval habitats in relation to hydrogeomorphological features at the confluence of the Kamo and Takano Rivers. A total of 78 egg masses were found. The spawning redds were concentrated in the transit ...
DOI:
10.1007/s10333-019-00743-0

36. Stream drift feeding and microhabitat competition of invasive smallmouth bass Micropterus dolomieu, native Japanese dace Tribolodon hakonensis and pale chub Opsariichthys platypus in the Nogu River, Japan

Author:
Miles I. Peterson; Satoshi Kitano
Source:
Environmental biology of fishes 2019 v.102 no.1 pp. 69-79
ISSN:
0378-1909
Subject:
Micropterus dolomieu; Opsariichthys; Tribolodon; feeding methods; foraging; indigenous species; microhabitats; rivers; streams; Japan
Abstract:
... Foraging behavior and microhabitat use of native Japanese dace, pale chub, and invasive smallmouth bass were studied in the Nogu River, Nagano, Japan. Chub, dace and smallmouth bass all used drift feeding as their dominant foraging behavior. Chub drift fed most frequently, followed by dace, and smallmouth bass drift fed significantly less frequently than both native species. Chub and dace utilized ...
DOI:
10.1007/s10641-019-0844-5

37. Trace of outbreeding between Biwa salmon (Oncorhynchus masou subsp.) and amago (O. m. ishikawae) detected from the upper reaches of inlet streams within Lake Biwa water system, Japan

Author:
Masayuki Kuwahara; Hiroshi Takahashi; Takeshi Kikko; Seiji Kurumi; Kei’ichiro Iguchi
Source:
Ichthyological research 2019 v.66 no.1 pp. 67-78
ISSN:
1341-8998
Subject:
Bayesian theory; Oncorhynchus masou; amplified fragment length polymorphism; anadromous fish; dams (hydrology); fish communities; haplotypes; hybridization; lakes; life history; males; mitochondrial DNA; outbreeding; plasticity; population structure; rivers; salmon; streams; Japan
Abstract:
... The establishment of fluvial fish populations from anadromous populations by natural or artificial barriers obstructing migration is a good research subject to study life history plasticity. Biwa salmon, Oncorhynchus masou subsp., a salmonid fish endemic to the Lake Biwa water system, exhibit life history variation (e.g., mature stream-resident males) in addition to a typical lacustrine life histo ...
DOI:
10.1007/s10228-018-0650-7

38. Tracing chronological shifts in farmland demarcation trees in southwestern Japan: implications from species distribution patterns, folk nomenclature, and multiple usage

Author:
Yoshinori Tokuoka; Fukuhiro Yamasaki; Kenichiro Kimura; Kiyokazu Hashigoe; Mitsunori Oka
Source:
Journal of ethnobiology and ethnomedicine 2019 v.15 no.1 pp. 21
ISSN:
1746-4269
Subject:
Celtis; Chaenomeles speciosa; Euonymus japonicus; Gardenia jasminoides; Salix; agricultural land; alluvial plains; color; crop production; elderly; farmers; geographical distribution; indigenous knowledge; industry; interviews; landscapes; livelihood; multivariate analysis; rivers; sericulture; species diversity; trees; vegetation; villages; youth; Japan
Abstract:
... BACKGROUND: Understanding the history of anthropogenic vegetation is often difficult due to the lack of tangible historical evidence. In this study, we examined chronological changes of farmland demarcation trees planted on alluvial plains along the Hijikawa River in southwestern Japan based on species distribution patterns, folk nomenclature, and multiple usage of the trees. METHODS: The species ...
DOI:
10.1186/s13002-019-0301-8
PubMed:
31029161
PubMed Central:
PMC6487015

39. Trend of 137Cs concentration in river water in the medium term and future following the Fukushima nuclear accident

Author:
Takahiro Nakanishi; Kazuyuki Sakuma
Source:
Chemosphere 2019 v.215 pp. 272-279
ISSN:
0045-6535
Subject:
accidents; cesium; equations; half life; migratory behavior; nuclear power; power plants; radionuclides; river water; rivers; seasonal variation; water temperature; Japan
Abstract:
... It is a critical to examine the migration behavior of radiocesium derived from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in river systems to predict the future contamination status and propose effective countermeasures to reduce exposure. We conducted a three-year-long observation (April 2015–March 2018) of the ¹³⁷Cs concentration in two rivers which located surrounding the FDNPP ...
DOI:
10.1016/j.chemosphere.2018.10.017

40. Use of high-resolution seismic reflection data for paleogeographical reconstruction of shallow Lake Yamanaka (Fuji Five Lakes, Japan)

Author:
L. Lamair; A. Hubert-Ferrari; S. Yamamoto; O. Fujiwara; Y. Yokoyama; E. Garrett; M. De Batist; V.M.A. Heyvaert; Evelien Boes; Atsunori Nakamura; Stephen Obrochta; Masanobu Shishikura; Yosuke Miyairi; Helmut Brückner; Eisuke Ono; Svenja Riedesel; Koen De Rycker; Yoshiki Sato; Jan Walstra; the QuakeRecNankai Team
Source:
Palaeogeography, palaeoclimatology, palaeoecology 2019 v.514 pp. 233-250
ISSN:
0031-0182
Subject:
basins; drilling; floodplains; geophysics; lakes; landscapes; lava; paleoecology; ponds; rivers; vegetation cover; volcanic activity; water supply; wetlands; Japan
Abstract:
... High-resolution seismic profiles, combined with the integration of published drilling data, provide a detailed paleoenvironmental history of Lake Yamanaka (Fuji Five Lakes, Japan). This study presents a detailed analysis of the different depositional stages of the area currently occupied by Lake Yamanaka (floodplain wetland, river and lake). From ca. 5500 cal yr BP to ca. 5050 cal yr BP, the Yaman ...
DOI:
10.1016/j.palaeo.2018.09.028

41. Use of sterols to monitor surface water quality change and nitrate pollution source

Author:
Kei Nakagawa; Hiroki Amano; Ronny Berndtsson; Yuji Takao; Takahiro Hosono
Source:
Ecological indicators 2019 v.107 pp. 105534
ISSN:
1470-160X
Subject:
coprostanol; drinking water; effluents; environmental indicators; nitrate nitrogen; nitrates; nitrite nitrogen; nitrites; pollution; rivers; summer; surface water; water quality; winter; Japan
Abstract:
... Coprostanol was tested as ecological indicator to trace domestic and manure effluents and to investigate possible pollution sources in surface water. Pollution assessment was performed by analysing NO3−, NO2−, coprostanol (5β(H)-Cholestan-3β-ol), and cholestanol (5α(H)-Cholestan-3β-ol) in water samples from 42 sites along rivers in Shimabara and Unzen City, Japan. NO2-N concentration exceeded 0.04 ...
DOI:
10.1016/j.ecolind.2019.105534

42. Using spectrocolourimetry to trace sediment source dynamics in coastal catchments draining the main Fukushima radioactive pollution plume (2011–2017)

Author:
Olivier Evrard; Roxanne Durand; Anthony Foucher; Tales Tiecher; Virginie Sellier; Yuichi Onda; Irène Lefèvre; Olivier Cerdan; J. Patrick Laceby
Source:
Journal of soils and sediments 2019 v.19 no.9 pp. 3290-3301
ISSN:
1439-0108
Subject:
accidents; autumn; color; cultivation area; decontamination; discriminant analysis; forests; landscapes; landslides; linear models; monitoring; nuclear power; organic matter; power plants; radioactive pollution; remediation; rivers; sediments; subsoil; surface area; topsoil; typhoons; watersheds; Japan
Abstract:
... PURPOSE: Spectrocolourimetric measurements provide a relatively inexpensive, quick and non-destructive alternative to the analysis of geochemical and organic matter properties. When used in the analysis of sediments and their potential sources, these colour parameters may provide important information on the dominant processes (i.e. erosion) occurring in the Critical Zone. Here, they are used to i ...
DOI:
10.1007/s11368-019-02302-w

43. Variability and change of precipitation and flood discharge in a Japanese river basin

Author:
Makoto Higashino; Heinz G. Stefan
Source:
Journal of hydrology 2019 v.21 pp. 68-79
ISSN:
2214-5818
Subject:
El Nino; atmospheric precipitation; basins; climate change; flood control; planning; river flow; rivers; runoff; watersheds; wet season; Japan; Pacific Ocean
Abstract:
... The Banjo River basin on Kyushu Island in the southwest of Japan.This study focuses on the impact of local and/or large scale climate change on the river flow in the small and steep river basin. The variability, trend, correlation and change of extreme and mean precipitation and river (flood) runoff are investigated.In the small and steep river basins of Japan, the maximum annual flood runoff whic ...
DOI:
10.1016/j.ejrh.2018.12.003

44. A data set of long‐term observation of aquatic vertebrates and associate environmental factors in a temperate stream, the Yura River, Kyoto, Japan

Author:
Hikaru Nakagawa
Source:
Ecological research 2019 v.34 no.1 pp. 8
ISSN:
0912-3814
Subject:
Japan; channelization; data collection; fish; fish communities; forests; land use; microhabitats; mortality; population density; population dynamics; research; rivers; streams; watersheds
Abstract:
... The population dynamics of fishes are strongly affected by habitat characteristics that are constantly changing due to seasonal and interannual variations in climatic, hydrological and geographical processes. Seasonal and interannual variations in hydrological events directly affect the movement, growth and mortality of stream fishes, and indirectly affect their population density and standing cro ...
DOI:
10.1111/1440-1703.1059

45. The importance of riparian subtropical lucidophyllous forest to odonate conservation

Author:
Masaru Sakai; Shin‐ichi Suda; Taichi Okeda; Ryosuke Nomura; Izumi Washitani
Source:
Aquatic conservation 2019 v.29 no.5 pp. 682-692
ISSN:
1052-7613
Subject:
Odonata; anthropogenic activities; flood control; forest types; habitats; indigenous species; lotic systems; riparian forests; rivers; species richness; streams; subtropics; Japan
Abstract:
... Glossy, broad‐leaved, evergreen (lucidophyllous) forests are found mainly in humid subtropical regions of East Asia and are recognized as a biodiverse biome harbouring numerous endemic species. To date, however, few studies have considered the conservation importance of rivers draining these unique environments. In this study, lotic Odonata were used as indicators to examine factors affecting ripa ...
DOI:
10.1002/aqc.3099

46. A modeling approach to estimate the 137Cs discharge in rivers from immediately after the Fukushima accident until 2017

Author:
Kazuyuki Sakuma; Takahiro Nakanishi; Kazuya Yoshimura; Hiroshi Kurikami; Kenji Nanba; Mark Zheleznyak
Source:
Journal of environmental radioactivity 2019 v.208-209 pp. 106041
ISSN:
0265-931X
Subject:
accidents; atmospheric deposition; cesium; coasts; equations; inventories; models; nuclear power; power plants; radioactivity; radionuclides; river water; rivers; water management; watersheds; Japan
Abstract:
... We developed a simple model to evaluate and predict the 137Cs discharge from catchments using a tank model and the L-Q equation. Using this model, the 137Cs discharge and discharge ratio from the Abukuma River and 13 other rivers in the Fukushima coastal region were estimated from immediately after the Fukushima accident up to 2017. The 137Cs discharge (and discharge ratio to the deposition invent ...
DOI:
10.1016/j.jenvrad.2019.106041

47. Application of Backpack-Mounted Mobile Mapping System and Rainfall–Runoff–Inundation Model for Flash Flood Analysis

Author:
Takahiro Sayama; Koji Matsumoto; Yuji Kuwano; Kaoru Takara
Source:
Water 2019 v.11 no.5 pp. -
ISSN:
2073-4441
Subject:
case studies; floods; models; mountains; remote sensing; rivers; satellites; sediments; surveys; topography; watersheds; Japan
Abstract:
... Satellite remote sensing has been used effectively to estimate flood inundation extents in large river basins. In the case of flash floods in mountainous catchments, however, it is difficult to use remote sensing information. To compensate for this situation, detailed rainfall–runoff and flood inundation models have been utilized. Regardless of the recent technological advances in simulation ...
DOI:
10.3390/w11050963

48. Assessing Spatial Flood Risk from Multiple Flood Sources in a Small River Basin: A Method Based on Multivariate Design Rainfall

Author:
Xinyu Jiang; Lijiao Yang; Hirokazu Tatano
Source:
Water 2019 v.11 no.5 pp. -
ISSN:
2073-4441
Subject:
case studies; drainage; multivariate analysis; rain; rainfall duration; risk; risk assessment; risk management; rivers; watersheds; Japan
Abstract:
... A key issue in assessing the spatial distribution of flood risk is considering risk information derived from multiple flood sources (river flooding, drainage inundation, etc.) that may affect the risk assessment area. This study proposes a method for assessing spatial flood risk that includes flooding and inundation in small-basin areas through multivariate design rainfall. The concept of critical ...
DOI:
10.3390/w11051031

49. Contrasting effects of dams with and without reservoirs on the population density of an amphidromous goby in southwestern Japan

Author:
Yoshifumi Sumizaki; Ryota Kawanishi; Mikio Inoue; Motohiro Takagi; Koji Omori
Source:
Ichthyological research 2019 v.66 no.3 pp. 319-329
ISSN:
1341-8998
Subject:
Rhinogobius; dams (hydrology); diadromous fish; freshwater fish; geographical distribution; hatching; juveniles; lakes; larvae; population density; rivers; streams; surface water; surveys; water storage; weirs; Japan
Abstract:
... Dam construction affects the distribution and abundance of freshwater fishes, particularly for diadromous species. Amphidromous fishes spawn in rivers, and hatched larvae descend to the sea (or standing water body such as lakes) immediately after hatching, grow there typically for a few months, and then ascend rivers as small juveniles. Landlocked populations of amphidromous fishes above dams and ...
DOI:
10.1007/s10228-018-00678-2

50. Contribution of precipitation to groundwater flow systems in three major alluvial fans in Toyama Prefecture, Japan: stable-isotope characterization and application to the use of groundwater for urban heat exchangers

Author:
Nagisa Okakita; Kaname Iwatake; Hiromichi Hirata; Akira Ueda
Source:
Hydrogeology journal 2019 v.27 no.1 pp. 345-362
ISSN:
1431-2174
Subject:
air conditioning; alluvial plains; groundwater; groundwater flow; heat exchangers; heat pumps; hydrogeology; melting; oxygen; river water; rivers; roads; runoff; snow; stable isotopes; summer; winter; Japan
Abstract:
... The isotopic compositions (D and ¹⁸O) of 177 precipitation samples collected at seven observation stations in Toyama Prefecture and one station in Gifu Prefecture in the northern part of central Japan were determined. The source and characteristics of the isotopes were clarified and their contribution to the groundwater flow systems of three major alluvial fans in the same area were investigated. ...
DOI:
10.1007/s10040-018-1850-y

51. Delayed impacts of the IOD: cross-seasonal relationships between the IOD, Tibetan Plateau snow, and summer precipitation over the Yangtze–Huaihe River region

Author:
Yue Zhang; Wen Zhou; Eric C. H. Chow; Marco Y. T. Leung
Source:
Climate dynamics 2019 v.53 no.7-8 pp. 4077-4093
ISSN:
0930-7575
Subject:
climate; electrical equipment; melting; monsoon season; rain; rivers; snow; summer; water vapor; winter; China; Indian Ocean; Japan
Abstract:
... Significant anomalous signals are found during the ensuing summer after the Indian Ocean Dipole (IOD) forcing mode dissipates over the tropical Indian Ocean. These signals manifest as increased summer precipitation over the Yangtze–Huaihe River (YHR) region associated with abnormal water vapor convergence contributed mainly by southerly water vapor input along the western flank of an anomalous ant ...
DOI:
10.1007/s00382-019-04774-5

52. Differential population dynamics of a coastal porpoise correspond to the fishing effort in a large estuarine system

Author:
Wenzhi Lin; Leszek Karczmarski; Jun Li; Stephen C.Y. Chan; Lang Guo; Yuping Wu
Source:
Aquatic conservation 2019 v.29 no.2 pp. 223-234
ISSN:
1052-7613
Subject:
Neophocaena phocaenoides; conservation status; demographic statistics; environmental indicators; estuaries; fisheries; habitats; models; monitoring; mortality; population dynamics; risk assessment; river deltas; rivers; China; Japan; Korean Peninsula; Yangtze River
Abstract:
... The finless porpoise (genus Neophocaena) is susceptible to fishery‐caused mortality, and its numbers are thought to be in decline across its entire range. However, population demographics have rarely been quantified for this genus, with a few exceptions of the narrow‐ridged form (Neophocaena asiaeorientalis) in waters off Japan, Korea, and in the Yangtze River of China, all of which show a drastic ...
DOI:
10.1002/aqc.2998

53. Dispersal Characteristics and Pathways of Japanese Glass Eel in the East Asian Continental Shelf

Author:
Yu-San Han; Kuan-Mei Hsiung; Heng Zhang; Lai-Yin Chow; Wann-Nian Tzeng; Akira Shinoda; Tatsuki Yoshinaga; Sung-Pyo Hur; Sun-Do Hwang; Yoshiyuki Iizuka; Shingo Kimura
Source:
Sustainability 2019 v.11 no.9 pp. -
ISSN:
2071-1050
Subject:
Anguilla japonica; aquaculture; continental shelf; eel; fish fry; fish larvae; otoliths; rivers; water currents; water temperature; China; Japan; Korean Peninsula; Taiwan; Yellow Sea
Abstract:
... The Japanese eel Anguilla japonica is an important aquaculture fish species in the East Asian countries of Japan, China, Korea, and Taiwan. All glass eel fry are captured from the wild and understanding the recruitment patterns of the glass eel is important. The larvae of A. japonica are passively transported to the East Asian Continental Shelf by the North Equatorial Current, the Kuroshio, the Ku ...
DOI:
10.3390/su11092572

54. Environmental DNA analysis reveals the spatial distribution, abundance, and biomass of Japanese eels at the river‐basin scale

Author:
Hikaru Itakura; Ryoshiro Wakiya; Satoshi Yamamoto; Kenzo Kaifu; Takuya Sato; Toshifumi Minamoto
Source:
Aquatic conservation 2019 v.29 no.3 pp. 361-373
ISSN:
1052-7613
Subject:
Anguilla japonica; DNA; biomass; catadromous fish; eel; endangered species; life history; monitoring; population dynamics; rivers; surveys; Japan
Abstract:
... There is growing international concern about declines in populations of anguillid eels, resulting in their inclusion in the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. Monitoring the population dynamics of these species is often challenging, however, owing to their broad distributions and complex, catadromous life histories. Whether environmental DNA ( ...
DOI:
10.1002/aqc.3058

55. Facultative amphidromy involving estuaries in an annual amphidromous fish from a subtropical marginal range

Author:
Iki Murase; Kei'ichiro Iguchi
Source:
Journal of fish biology 2019 v.95 no.6 pp. 1391-1398
ISSN:
0022-1112
Subject:
Japan; Plecoglossus altivelis ryukyuensis; adults; body size; diadromous fish; estuaries; food availability; freshwater; otoliths; rivers; salinity
Abstract:
... Variation in the life cycle of diadromous fishes can be explained by differential food availability between marine and freshwater habitats, since migration is often interpreted as a mechanism for exploiting food resources. Theoretically, a migration pattern of mainly remaining in freshwater occurs in tropical and subtropical habitats where fluvial productivity possibly exceeds marine productivity. ...
DOI:
10.1111/jfb.14147

56. Georeferenced multimedia environmental fate of volatile methylsiloxanes modeled in the populous Tokyo Bay catchment basin

Author:
Takeo Sakurai; Yoshitaka Imaizumi; Keisuke Kuroda; Takehiko I. Hayashi; Noriyuki Suzuki
Source:
Science of the total environment 2019 v.689 pp. 843-853
ISSN:
0048-9697
Subject:
basins; emissions; environmental fate; georeferencing; households; models; rivers; sediments; sewage systems; sewage treatment; siloxanes; wastewater; wastewater treatment; watersheds; Japan
Abstract:
... We investigated the multimedia fate of decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) in the densely populated catchment basin of Tokyo Bay, Japan, by using a georeferenced multimedia model. We estimated the daily per person consumption rate of these compounds in Japan according to literature. Emissions to the atmosphere accounted for almost all of the emissions of these ...
DOI:
10.1016/j.scitotenv.2019.06.462

57. High resilience of aquatic community to a 100-year flood in a gravel-bed river

Author:
Junjiro N. Negishi; Akira Terui; Badrun Nessa; Kazuki Miura; Takeaki Oiso; Keizo Sumitomo; Tomoko Kyuka; Mitsuaki Yonemoto; Futoshi Nakamura
Source:
Landscape and ecological engineering 2019 v.15 no.2 pp. 143-154
ISSN:
1860-1871
Subject:
Oncorhynchus mykiss; aquatic ecosystems; aquatic food webs; carbon; diarrhea; fauna; fish; food chain; gravel; landscapes; nitrogen; riparian forests; rivers; stable isotopes; stream channels; Japan
Abstract:
... Our understanding of ecosystem responses to exceedingly large rare flood events is currently limited. We report the resilience of aquatic community to a 100-year record-high flood, and how it varies depending on levels of water pollution, in a fourth-order gravel-bed river in northern Japan. We used data on riparian landscape structure, channel morphology, and community structure of aquatic fauna, ...
DOI:
10.1007/s11355-019-00373-y

58. Impacts of previous maintenance of river embankments on the grassland communities by changing soil properties

Author:
Tomoyo F. Koyanagi; Susumu Yamada; Hirotoshi Matsuzaki; Yuichi Kato
Source:
Ecological engineering 2019 v.131 pp. 73-80
ISSN:
0925-8574
Subject:
environmental factors; grasslands; habitats; linear models; rivers; sand; soil properties; soil surveys; species richness; Japan
Abstract:
... River embankments can be the potential semi-natural habitats for grassland species, although the recent disturbances for maintenance would alter overall vegetation of river embankments. For evaluating possibility of grassland species conservation in vegetation of river embankments, we aimed to clarify how does the previous maintenances (i.e. disturbance history) influence current species compositi ...
DOI:
10.1016/j.ecoleng.2019.03.004

59. Numerical study of transport pathways of 137Cs from forests to freshwater fish living in mountain streams in Fukushima, Japan

Author:
Hiroshi Kurikami; Kazuyuki Sakuma; Alex Malins; Yoshito Sasaki; Tadafumi Niizato
Source:
Journal of environmental radioactivity 2019 v.208-209 pp. 106005
ISSN:
0265-931X
Subject:
accidents; cesium; foods; forest litter; forest soils; forested watersheds; forests; freshwater fish; leaves; losses from soil; models; nuclear power; organic soils; power plants; radioactivity; radionuclides; river water; rivers; streams; Japan
Abstract:
... The accident at the Fukushima Dai-ichi Nuclear Power Plant in 2011 released a large quantity of radiocesium into the surrounding environment. Radiocesium concentrations in some freshwater fish caught in rivers in Fukushima Prefecture in October 2018 were still higher than the Japanese limit of 100 Bq kg−1 for general foodstuffs. To assess the uptake of 137Cs by freshwater fish living in mountain s ...
DOI:
10.1016/j.jenvrad.2019.106005

60. OH defects in quartz as a provenance tool: Application to fluvial and deep marine sediments from SW Japan

Author:
Dominik Jaeger; Roland Stalder; Hideki Masago; Michael Strasser
Source:
Sedimentary geology 2019 v.388 pp. 66-80
ISSN:
0037-0738
Subject:
Fourier transform infrared spectroscopy; basins; data collection; deformation; glaciofluvial deposits; marine sediments; mixing; provenance; quartz; rivers; sediment deposition; wells; Japan; Pacific Ocean
Abstract:
... Hydrogen-related point defects (OH defects) in the crystal lattice of detrital, monocrystalline quartz have been proposed as an indicator to distinguish different sediment sources, making it a potential tool for provenance analysis. This study tests this novel technique on samples from SW Japan by comparing the results of OH defect analyses with those of “classical” provenance studies. OH defects ...
DOI:
10.1016/j.sedgeo.2019.05.003

61. Seasonal morphodynamic evolution in a meandering channel of a macrotidal estuary

Author:
Gubash Azhikodan; Katsuhide Yokoyama
Source:
Science of the total environment 2019 v.684 pp. 281-295
ISSN:
0048-9697
Subject:
dry season; estuaries; global positioning systems; monitoring; river flow; rivers; salinity; sediment transport; sediments; surveys; topography; turbidity; wet season; Japan
Abstract:
... The spatio-temporal morphodynamics in relation to the fortnightly tidal variations and seasonal river discharge variations in a meandering estuarine channel were investigated. Intensive topographic surveys (longitudinal and transverse) every 3–4 months using a digital sonar system equipped with a differential global positioning system and continuous monitoring of salinity and turbidity with moored ...
DOI:
10.1016/j.scitotenv.2019.05.289

62. Seasonal variations in nutrients and biogenic particles in the upper and lower layers of East China Sea Shelf and their export to adjacent seas

Author:
Yucheng Wang; Xinyu Guo; Liang Zhao; Jing Zhang
Source:
Progress in oceanography 2019 v.176 pp. 102138
ISSN:
0079-6611
Subject:
continental shelf; detritus; ecosystems; inventories; models; nutrients; phytoplankton; rivers; seasonal variation; East China Sea; Japan; Yangtze River
Abstract:
... Based on a three dimensional low-trophic ecosystem model, we revaluated budgets of nutrients and biogenic particles (phytoplankton and detritus) in the East China Sea (ECS), a continental shelf sea with high productivity that is affected by a large river (Changjiang River) and a western boundary current (Kuroshio). Following careful comparison of model results with available observation data, we c ...
DOI:
10.1016/j.pocean.2019.102138

63. Simulation of natural capital and ecosystem services in a watershed in Northern Japan focusing on the future underuse of nature: by linking forest landscape model and social scenarios

Author:
Chihiro Haga; Takahiro Inoue; Wataru Hotta; Rei Shibata; Shizuka Hashimoto; Hiroko Kurokawa; Takashi Machimura; Takanori Matsui; Junko Morimoto; Hideaki Shibata
Source:
Sustainability science 2019 v.14 no.1 pp. 89-106
ISSN:
1862-4065
Subject:
age structure; biomass; case studies; decision making; ecosystem services; forests; land management; landscapes; natural capital; pastures; population distribution; rivers; simulation models; species diversity; sustainability science and engineering; terrestrial ecosystems; watersheds; Japan
Abstract:
... A quantitative scenario approach to compare the future state of natural capital and ecosystem services (ESs) plays a key role in facilitating decision-making for the sustainable management of landscapes. In Japan, the shrinking and aging population will likely lead to a situation of underuse of natural resources, resulting in rewilding of terrestrial ecosystems. This study conducted a quantitative ...
DOI:
10.1007/s11625-018-0623-9

64. Spatial and temporal changes in genetic structure and diversity of isolated white-spotted charr (Salvelinus leucomaenis) populations

Author:
Shoichiro Yamamoto; Kentaro Morita; Genki Sahashi
Source:
Hydrobiologia 2019 v.840 no.1 pp. 35-48
ISSN:
0018-8158
Subject:
Salvelinus leucomaenis; anadromous fish; dams (hydrology); effective population size; erosion control; fish communities; freshwater fish; gene flow; genetic markers; genetic variation; habitat fragmentation; heterozygosity; hydroelectric power; microsatellite repeats; population structure; power generation; rivers; temporal variation; Japan
Abstract:
... In Japan, numerous artificial dams constructed for erosion control or hydroelectric power generation have affected almost all rivers and resulted in isolation and fragmentation of many freshwater fish populations. We examined genetic structure and diversity of two temporally isolated samples (spanning 15 years) from 23 white-spotted charr (Salvelinus leucomaenis) populations, including above- and ...
DOI:
10.1007/s10750-019-3924-9

65. Spatial variation in sedimentary radioactive cesium concentrations in Tokyo Bay following the Fukushima Daiichi Nuclear Power Plant accident

Author:
Atsushi Kubo; Kai Tanabe; Yukari Ito; Takashi Ishimaru; Hisayuki Arakawa; Jota Kanda
Source:
Chemosphere 2019 v.235 pp. 550-555
ISSN:
0045-6535
Subject:
accidents; cesium; coastal water; estuaries; inventories; microparticles; nuclear power; power plants; radioactivity; radionuclides; rivers; sediments; watersheds; Japan
Abstract:
... Cesium-137 concentrations in sediment (137Cs) at Tokyo Bay were measured at 26 stations during 2017. Average 137Cs concentrations at the Arakawa river mouth (117 ± 46 Bq kg−1) were approximately six times higher than those of the other stations in the bay (20 ± 16 Bq kg−1). There were radiocesium-bearing microparticles in the bay sediment as well as in suspended matter of Fukushima coastal waters. ...
DOI:
10.1016/j.chemosphere.2019.06.215

66. Study of aquatic ecological regions using fish fauna and geographic archipelago factors

Author:
Rei Itsukushima
Source:
Ecological indicators 2019 v.96 pp. 69-80
ISSN:
1470-160X
Subject:
climate; coastal water; ecoregions; ecosystems; environmental indicators; fauna; fish; floodplains; islands; issues and policy; local government; quantitative analysis; researchers; rivers; water currents; watersheds; Japan
Abstract:
... An evaluation of ecological integrity is required for ecosystem conservation and restoration. The ecological region, or “ecoregion”, has been adopted as a unit of geological area to enable a comparison of the ecological integrity of different regions. The delineation of an ecological region is difficult in countries in East Asia, including Japan because of complex topographies (i.e., several penin ...
DOI:
10.1016/j.ecolind.2018.08.057

67. Temporal and spatial change in phosphate–phosphorus concentration and modeling with land-use variation in Sengari reservoir basin, Japan

Author:
Baobab Kibet Kimengich; Junichiro Takeuchi; Keitaro Goto; Masayuki Fujihara
Source:
Paddy and water environment 2019 v.17 no.2 pp. 131-139
ISSN:
1611-2490
Subject:
aquatic ecosystems; basins; eutrophication; forests; golf courses; irrigation scheduling; land use; models; nutrients; paddies; phosphate phosphorus; pollutants; pollution load; regression analysis; residential areas; rivers; septic systems; sewage treatment; total phosphorus; water quality; water treatment; Japan
Abstract:
... Severe degradation of water quality from nutrient pollutants has increased eutrophication that affects aquatic ecosystems and increases the cost of water treatment. This study was conducted in the Sengari Reservoir basin, which experiences high eutrophication due to phosphorus in the nutrient load it receives. Dissolved phosphate–phosphorus (PO₄–P) accounts for the highest ratio of total phosphoru ...
DOI:
10.1007/s10333-019-00705-6

68. Transport and Redistribution of Radiocesium in Fukushima Fallout through Rivers

Author:
Keisuke Taniguchi; Yuichi Onda; Hugh G. Smith; William Blake; Kazuya Yoshimura; Yosuke Yamashiki; Takayuki Kuramoto; Kimiaki Saito
Source:
Environmental science & technology 2019 v.53 no.21 pp. 12339-12347
ISSN:
1520-5851
Subject:
Japan; accidents; cesium radioisotopes; decline; environmental science; forests; nuclear power; paddies; power plants; rivers; sediments; technology; watersheds; Ukraine
Abstract:
... The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident released the most significant quantity of radiocesium into the environment since Chernobyl, and detailed measurements over the initial 5 years provide new insights into fluvial redistribution of radiocesium. We found that the high initial activity concentration of ¹³⁷Cs-bearing suspended sediment in rivers was followed by a steep exponenti ...
DOI:
10.1021/acs.est.9b02890

69. Water quality and pollution loading of a river segment affected by landfill leachate and domestic waste

Author:
Vanseng Chounlamany; Maria Antonia Tanchuling; Takanobu Inoue
Source:
International journal of environmental studies 2019 v.76 no.3 pp. 379-395
ISSN:
1029-0400
Subject:
agricultural wastes; biochemical oxygen demand; chemical oxygen demand; dissolved oxygen; dry season; electrical conductivity; landfill leachates; landfills; monitoring; river water; rivers; streams; total dissolved solids; total suspended solids; water quality; Europe; Japan; Philippines
Abstract:
... The Marikina River in the Philippines has been polluted by Payatas landfill leachate, and domestic and agricultural waste. This study monitored the water quality at five stations on the river and two stations on two creeks that discharge to the river to determine the effects of Payatas landfill and to estimate pollution loading. The dissolved oxygen (DO), chemical oxygen demand (COD) and other wat ...
DOI:
10.1080/00207233.2018.1507874

70. The growth and nutrient uptake of invasive vines on contrasting riverbank soils

Author:
M. Harun Rashid; Md Nazim Uddin; Animesh Sarkar; Mahfuza Parveen; Takashi Asaeda
Source:
River research and applications 2019 v.35 no.6 pp. 749-758
ISSN:
1535-1459
Subject:
Pueraria montana var. lobata; Sicyos angulatus; belowground biomass; clones; habitats; invasive species; nutrient content; nutrient uptake; plant growth; plants (botany); resource allocation; riparian areas; riparian soils; rivers; soil heterogeneity; soil nutrients; starch; tissues; total nitrogen; total phosphorus; Japan
Abstract:
... This study sought to investigate the research question as to whether the growth and nutrient uptake of two invasive vines, Pueraria lobata and Sicyos angulatus, are affected by the heterogeneity of soil characteristics of two riverbank sites with different flooding regimes. Soil, individual ramets of P. lobata and S. angulatus plants were sampled monthly from quadrats set on homogenous stands from ...
DOI:
10.1002/rra.3435

71. A molecular approach to identification of protonemata helps assess biodiversity of extremely acidic freshwaters

Author:
Dovilė Barcytė; Jan Fott; Linda Nedbalová
Source:
Limnology 2019 v.20 no.2 pp. 225-231
ISSN:
1439-8621
Subject:
adults; algae; biodiversity; chloroplasts; genes; genetic markers; habitats; internal transcribed spacers; lakes; mitochondria; mosses and liverworts; pH; phylogeny; protonemata; ribosomal DNA; ribulose-bisphosphate carboxylase; rivers; Japan
Abstract:
... Macroscopic fuzzy clumps of green filaments resembling filamentous algae were found on multiple sampling occasions in the water close to the shore of the extremely acidic (pH < 3) Hromnice Lake in Czechia. Microscopic investigation revealed that these filaments were moss protonemata. In order to identify the moss, we sequenced chloroplast (rbcL), mitochondrial (nad5), and nuclear (ITS2) molecular ...
DOI:
10.1007/s10201-019-00570-6