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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. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

12. 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

13. 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

14. 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

15. 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

16. 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

17. 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

18. 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

19. 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

20. 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