scholarly journals Natal origin and migration pathways of Mekong catfish (Pangasius krempfi) using strontium isotopes and trace element concentrations in environmental water and otoliths

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252769
Author(s):  
Ngan Trong Tran ◽  
Maylis Labonne ◽  
Ming-Tsung Chung ◽  
Chia-Hui Wang ◽  
Kuo-Fang Huang ◽  
...  
Keyword(s):  
Trace Element ◽  
Mekong Delta ◽  
Environmental Water ◽  
Mekong River ◽  
Migration Routes ◽  
Natal Origin ◽  
Element Concentrations ◽  
Migration Pathway ◽  
And Migration ◽  
Migration Pathways

To improve our knowledge of the migration pathway of a highly threatened fish species along the Mekong River, strontium isotope ratios (87Sr/86Sr) and 18 trace element concentrations were measured in the water and in the otoliths of an anadromous catfish, Pangasius krempfi, to infer its natal origin and potential migration pathways. Water was sampled at 18 locations along the mainstream, tributaries and distributaries of the Mekong River. To check for accuracy and precision, measurements of the 87Sr/86Sr ratios and trace element concentrations were then compared in two laboratories that use different analytical methods. Differences in trace element concentrations between locations were not significant and could not, therefore, be used to discriminate between migration pathways. However, the Mekong mainstream, tributaries and distributaries could all be discriminated using Sr isotopes. The 87Sr/86Sr profiles recorded in P. krempfi otoliths showed that there were three contingents with obligate freshwater hatching and variable spawning sites along the Mekong mainstream, from Phnom Penh (Cambodia) to Nong Khai (Thailand) or further. After hatching, the fish migrated more or less rapidly to the Mekong Delta and then settled for most of their lifetime in brackish water. Spawning habitats and migration routes may be threatened by habitat shifts and the increasing number of hydropower dams along the river, especially the contingents born above Khone Falls (Laos). The conservation of P. krempfi, as well as other migratory fish in the Mekong River, requires agreements, common actions and management by all countries along the Mekong River. This study highlighted the importance of using both Sr/Ca and 87Sr/86Sr ratios to understand life history of anadromous fishes as the 87Sr/86Sr ratio in the water was shown to be less effective than the Sr/Ca ratio in identifying movements between different saline areas.

scholarly journals Assessment of population size and migration routes of silver eel in the River Rhine based on a 2-year combined mark-recapture and telemetry study

2007 ◽  
Vol 64 (7) ◽  
pp. 1450-1456 ◽  
Author(s):  
Jan Klein Breteler ◽  
Tim Vriese ◽  
Jost Borcherding ◽  
André Breukelaar ◽  
Lothar Jörgensen ◽  
...  
Keyword(s):  
Population Size ◽  
Downstream Migration ◽  
Migration Route ◽  
River Rhine ◽  
Migration Routes ◽  
Silver Eel ◽  
Mark Recapture ◽  
And Migration ◽  
Migration Pathways ◽  
Combined Mark

Abstract Klein Breteler, J., Vriese, T., Borcherding, J., Breukelaar, A., Jörgensen, L., Staas, S., de Laak, G., and Ingendahl, D. 2007. Assessment of population size and migration routes of silver eel in the River Rhine based on a 2-year combined mark-recapture and telemetry study. – ICES Journal of Marine Science, 64: 1450–1456. More than 3000 female silver eels >50 cm were marked and released in the River Rhine at Cologne in 2004 and 2005, and more than 4000 and 6000 per year, respectively, were checked for marks in the different Rhine branches close to the sea. Migration pathways of downstream-migrating eels were also tracked by telemetry from the point of release (300–350 km from the sea, depending on the migration route) through the three main branches of the Rhine (Waal, Nederrijn + Lek, IJssel + Lake IJsselmeer) to the sea. Downstream migration to the sea took from <2 d to more than a year, but was generally in October and November of the year of release. Most successful migrators seemed to find their way to the sea via the Nieuwe Waterweg rather than via Lake IJsselmeer or Haringvliet. Some 23% of released eels of the 2004 cohort and 15% of the 2005 cohort made it to the sea in less than 2 years. The telemetry data suggest that the Nederrijn + Lek watercourse, the only location where hydropower stations have been built in the lower Rhine system, might be important for downstream migration of eels only in the years with greater discharges, suggesting that management measures should concentrate on the Waal and downstream sections to improve spawning escapement of the silver eel population of the Rhine system.

INTEGRATED SOURCE, MATURATION AND MIGRATION ANALYSIS, GIPPSLAND BASIN, AUSTRALIA

1992 ◽  
Vol 32 (1) ◽  
pp. 313 ◽  
Author(s):  
P. S. Moore ◽  
B. J. Burns ◽  
J. K. Emmett ◽  
D. A. Guthrie
Keyword(s):  
Source Rocks ◽  
Source Distribution ◽  
Integrated Analysis ◽  
Peak Oil ◽  
Gas Generation ◽  
Southeastern Part ◽  
Migration Pathway ◽  
And Migration ◽  
Gippsland Basin ◽  
Migration Pathways

Biomarker geochemistry, maturation modelling and migration pathway analysis have been used in a new, integrated analysis of the Gippsland Basin. The analysis has resulted in the development of a predictive model for hydrocarbon charge and oil versus gas split. The study was carried out in 4 parts: analytical geochemistry, source distribution mapping, maturation modelling and migration pathway analysis.New geochemical biomarker studies confirm a non-marine source for the oils, but place peak oil generation in the upper part of the traditional oil window. Gas in the basin is mainly derived from overmature source rocks. Coals were recognised to contribute significantly to oil generation.The source rock thickness and distribution for the entire basin were mapped using analytical techniques plus wireline log analysis, coupled with seismic structural mapping and facies analysis. Prime oil-prone source rocks were found to be located in the lower coastal plain depositional environment. Extrapolations were necessary for older rocks, using stratigraphic models.Maturation modelling modelling of selected wells and synclines was carried out and an overall basin model constructed. Post-structuring yields of oil and gas were also derived. A key result was the lack of post-structuring overmature gas generation in the oil prone southeastern part of the basin, owing to high palaeo-temperatures associated with earlier rifting.Analysis of present day and palaeo-migration pathways gave an excellent match between predicted oil versus gas ratios and discoveries, both geographically and stratigraphically. The tool is now being used in a predictive mode to highgrade basin prospectivity.

scholarly journals The systematics and paleobiogeographic significance of Sub-Boreal and Boreal ammonites (Aulacostephanidae and Cardioceratidae) from the Upper Jurassic of the Bohemian Massif

2014 ◽  
Vol 65 (5) ◽  
pp. 378-389 ◽  
Author(s):  
Jan Hrbek
Keyword(s):  
Bohemian Massif ◽  
Upper Jurassic ◽  
Museum Collections ◽  
Systematic Revision ◽  
Marine Deposits ◽  
Migration Pathway ◽  
The Family ◽  
And Migration ◽  
Migration Pathways ◽  
Lower Kimmeridgian

Abstract Upper Jurassic marine deposits are either rarely preserved due to erosion or buried under younger sediments in the Bohemian Massif. However, fossil assemblages from a few successions exposed in northern Bohemia and Saxony and preserved in museum collections document the regional composition of macro-invertebrate assemblages and thus provide unique insights into broad-scale distribution and migration pathways of ammonites during the Late Jurassic. In this paper, we focus on the systematic revision of ammonites from the Upper Oxfordian and Lower Kimmeridgian deposits of northern Bohemia and Saxony. The ammonites belong to two families (Aulacostephanidae and Cardioceratidae) of high paleobiogeographic and stratigraphic significance. Six genera belong to the family Aulacostephanidae (Prorasenia, Rasenia, Eurasenia, Rasenioides, Aulacostephanus, Aulacostephanoides) and one genus belongs to the family Cardioceratidae (Amoeboceras). They show that the Upper Jurassic deposits of the northern Bohemian Massif belong to the Upper Oxfordian and Lower Kimmeridgian and paleobiogeographically correspond to the German-Polish ammonite branch with the geographical extent from the Polish Jura Chain to the Swabian and Franconian Alb. Therefore, the occurrences of ammonites described here imply that migration pathway connecting the Polish Jura Chain with habitats in southern Germany was located during the Late Oxfordian and Early Kimmeridgian in the Bohemian Massif.

ASSESSMENT OF TRACE ELEMENT CONCENTRATIONS IN THE FARMINGTON RIVER, HARTFORD COUNTY, CT

2016 ◽  
Author(s):  
Matthew Costa ◽  
◽  
Carley M. Cavanaugh ◽  
Oluyinka Oyewumi
Keyword(s):  
Trace Element ◽  
Element Concentrations

scholarly journals Paracellular and Transcellular Leukocytes Diapedesis Are Divergent but Interconnected Evolutionary Events

Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 254
Author(s):  
Michel-Edwar Mickael ◽  
Norwin Kubick ◽  
Pavel Klimovich ◽  
Patrick Henckell Flournoy ◽  
Irmina Bieńkowska ◽  
...  
Keyword(s):  
Immune Cell ◽  
Critical Role ◽  
Cellular Polarity ◽  
Endothelial Layer ◽  
Trichoplax Adhaerens ◽  
Migration Pathway ◽  
Two Systems ◽  
Sequence Reconstruction ◽  
Rhoa Protein ◽  
Migration Pathways

Infiltration of the endothelial layer of the blood-brain barrier by leukocytes plays a critical role in health and disease. When passing through the endothelial layer during the diapedesis process lymphocytes can either follow a paracellular route or a transcellular one. There is a debate whether these two processes constitute one mechanism, or they form two evolutionary distinct migration pathways. We used artificial intelligence, phylogenetic analysis, HH search, ancestor sequence reconstruction to investigate further this intriguing question. We found that the two systems share several ancient components, such as RhoA protein that plays a critical role in controlling actin movement in both mechanisms. However, some of the key components differ between these two transmigration processes. CAV1 genes emerged during Trichoplax adhaerens, and it was only reported in transcellular process. Paracellular process is dependent on PECAM1. PECAM1 emerged from FASL5 during Zebrafish divergence. Lastly, both systems employ late divergent genes such as ICAM1 and VECAM1. Taken together, our results suggest that these two systems constitute two different mechanical sensing mechanisms of immune cell infiltrations of the brain, yet these two systems are connected. We postulate that the mechanical properties of the cellular polarity is the main driving force determining the migration pathway. Our analysis indicates that both systems coevolved with immune cells, evolving to a higher level of complexity in association with the evolution of the immune system.

scholarly journals Invasive Plant Species Distribution Is Structured by Soil and Habitat Type in the City Landscape

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 773
Author(s):  
Ilona Szumańska ◽  
Sandra Lubińska-Mielińska ◽  
Dariusz Kamiński ◽  
Lucjan Rutkowski ◽  
Andrzej Nienartowicz ◽  
...  
Keyword(s):  
Distribution Pattern ◽  
Species Distribution ◽  
Human Activities ◽  
Invasive Plant ◽  
Habitat Type ◽  
Permanent Plots ◽  
Human Land Use ◽  
And Migration ◽  
Migration Pathways ◽  
The City

Invasive alien species (IAS) is a global problem that largely relates to human activities and human settlements. To prevent the further spread of IAS, we first need to know their pattern of distribution, to determine which constitutes the greatest threat, and understand which habitats and migration pathways they prefer. Our research aimed to identify the main vectors and distribution pattern of IAS of plants in the city environment. We checked the relations between species distribution and such environmental factors as urban soil type and habitat type. We applied data on IAS occurrence (collected in the period 1973–2015) in 515 permanent plots with dimensions of 0.5 × 0.5 km and analyzed by direct ordination methods. In total, we recorded 66 IAS. We found a 27% variance in the IAS distribution pattern, which can be explained by statistically significant soil and habitat types. The most important for species distribution were: river and alluvial soils, forests and related rusty soils, and places of intensive human activities, including areas of urbisols and industriosols. Our results provide details that can inform local efforts for the management and control of invasive species, and they provide evidence of the different associations between natural patterns and human land use.

scholarly journals Caught in the Crossfire: Challenges to Migrant Protection in the Yemeni and Libyan Conflicts

2020 ◽  
Vol 8 (4) ◽  
pp. 318-331
Author(s):  
Danielle Flanagan
Keyword(s):  
Legal Framework ◽  
International Humanitarian Law ◽  
Humanitarian Law ◽  
Armed Groups ◽  
Migration Routes ◽  
Conflict Zones ◽  
Conflict Situations ◽  
Stable Conditions ◽  
The Cost ◽  
Migration Pathways

In spite of the prevailing security dynamics in Yemen and Libya, both states continue to serve as areas of transit along some of the world’s largest mixed migration routes, leaving migrants caught in the crossfire of the two conflicts. This article examines the legal framework governing the protection of migrants in armed conflict under international humanitarian and human rights law. It also identifies two adverse incentives produced by the conflict situations that impede the exercise of these legal protections: (1) profits derived from migrant smuggling and trafficking, and (2) the use of migrants to support armed groups. In the absence of stable conditions in Yemen and Libya, individuals have little reason to respect international legal protections and discontinue migrant abuse connected with the lucrative businesses of smuggling and trafficking. The intractable nature of the two conflicts has also led to the strategic use of migrants as armed support, and more specifically as combatants, weapons transports, and human shields. Given these realities, the article outlines several recommendations to address the issue of migrant abuse in conflict. It recommends that states, particularly those neighboring Yemen and Libya, strengthen regular migration pathways to help reduce the number of migrants transiting through active conflict zones. It further advises that the international community increase the cost of noncompliance to international humanitarian law through the use of accountability mechanisms and through strategic measures, including grants of reciprocal respect to armed groups that observe protections accorded to migrants in conflict situations.

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