Spatial Distributions of Surface Sedimentary Organics and Sediment Profile Image Characteristics in a High-Energy Temperate Marine RiOMar: The West Gironde Mud Patch

The spatial distributions of (1) surface sediment characteristics (D0.5, Sediment Surface Area (SSA), Particulate Organic Carbon (POC), Chlorophyll-a (Chl-a), Phaeophytin-a (Phaeo-a), Total and Enzymatically Hydrolyzable Amino Acids (THAA, EHAA), δ13C) and (2) sediment profile image (apparent Redox Potential Discontinuity (aRPD), numbers and depths of biological traces) characteristics were quantified based on the sampling of 32 stations located within the West Gironde Mud Patch (Bay of Biscay, NE Atlantic) in view of (1) assessing the spatial structuration of a temperate river-dominated ocean margin located in a high-energy area, (2) disentangling the impacts of hydrodynamics and bottom trawling on this structuration, and (3) comparing the West Gironde Mud Patch with the Rhône River Prodelta (located in a low-energy area). Results support the subdivision of the West Gironde Mud Patch in a proximal and a distal part and show (1) the existence of depth gradients in surface sedimentary organics characteristics and bioturbation within the distal part; (2) no evidence for a significant effect of bottom trawling, as opposed to Bottom Shear Stress, on the West Gironde Mud Patch spatial structuration; and (3) major discrepancies between spatial structuration in the West Gironde Mud Patch and the Rhône River Prodelta, which were attributed to differences in tidal regimes, sedimentation processes, and local hydrodynamics, which is in agreement with current river-dominated ocean margin typologies.

Download Full-text

Spatial Distributions and Model Selections of Commercial Estuarine Fish (Sciaenidae) Populations Related to Water Quality, Chl-a, and AML in Musi River mouth, South Sumatra

3BIO: Journal of Biological Science, Technology and Management ◽

10.5614/3bio.2021.3.2.1 ◽

2021 ◽

Vol 3 (2) ◽

pp. 1-11

Author(s):

Andriwibowo Andriwibowo ◽

Adi Basukriadi ◽

Erwin Nurdin

Keyword(s):

Water Quality ◽

Chlorophyll A ◽

River Mouth ◽

Estuarine Fish ◽

Limiting Factor ◽

Spatial Distributions ◽

The West ◽

Chl A ◽

East River ◽

River Mouths

Estuary and river mouth are essential habitats for many commercial estuarine fishes, including the Sciaenidae family. While recently, estuaries have been threatened by anthropogenic marine litter (AML) transported from nearby land and river. An important type of AML is plastic litter since it takes a long degradation time. In the South Sumatra Province, Indonesia, one of the vital estuaries is the Musi estuary. This paper aims to map the spatial distributions of two Sciaenids, including Panna microdon and Otolithoides pama, and Sciaenid’s environmental covariates, including water quality, chlorophyll a, and plastic litters in Musi estuary and model the correlations of Sciaenids with their covariates. The maps were developed using GIS, and the model was validated using AIC methods. The data were collected from 3 river mouths in the west, central, and east of the Musi estuary. The data showed that the populations of both Sciaenids were higher in the east river mouth rather than in the west. Sciaenid populations were positively correlated with high salinity, DO, chlorophyll a, moderate transparency, and low temperature. A high load of AML’s frequency (7.54 items/m2) and weights (36.8 gram/m2) has reduced both Sciaenid populations in the central river mouth of the estuary. In contrast, low AML loads in the east have correlated with high Sciaenid populations. Model selection based on AIC values shows the best model for P.microdon retained an effect of AML weight with AIC values of 22.591 and 28.321 for O. pama. This concludes that the weight of plastic litter in estuary water was the main limiting factor for Sciaenid populations in Musi.

Download Full-text

Comparison of ecological quality indices based on benthic macrofauna and sediment profile images: A case study along an organic enrichment gradient off the Rhône River

Ecological Indicators ◽

10.1016/j.ecolind.2011.04.028 ◽

2012 ◽

Vol 12 (1) ◽

pp. 133-142 ◽

Cited By ~ 15

Author(s):

Céline Labrune ◽

Alicia Romero-Ramirez ◽

Jean Michel Amouroux ◽

Jean Claude Duchêne ◽

Martin Desmalades ◽

...

Keyword(s):

Benthic Macrofauna ◽

Organic Enrichment ◽

Ecological Quality ◽

Quality Indices ◽

Rhône River ◽

Sediment Profile ◽

Rhone River

Download Full-text

Effects of monsoon activity on monthly phytoplankton blooms in the gulf of Thailand in El Nino year 2002

VNU Journal of Science Earth and Environmental Sciences ◽

10.25073/2588-1094/vnuees.4232 ◽

2018 ◽

Vol 34 (2) ◽

Author(s):

Thien Le

Keyword(s):

El Niño ◽

El Nino ◽

Surface Wind ◽

Spatial Distributions ◽

Gulf Of Thailand ◽

Northeast Monsoon ◽

Phytoplankton Blooms ◽

The West ◽

Chl A ◽

The Gulf Of Thailand

ABSTRACT: The Gulf of Thailand is a semi-closed Gulf on the west and southwest side of the Indochina Penisula and experienced reversal monsoon. The object of the present study is to investigate monthly and spatial distributions of the phytoplankton in the Gulf of Thailand during whole El Nino year 2002 by using remote-sensing measurements of chlorophyll-a (Chl-a) and surface wind vectors. Results show that monthly and spatial variations of the phytoplankton blooms are primarily associated with the monsoonal winds. In general, the average monthly Chl-a concentrations were quite low (<0.5 mg m-3) most area of the Gulf, with a belt of higher Chl-a concentrations along the coast during throughout year. Phytoplankton blooms extensively offshore in the near-coastal area of the Gulf in January and February, which is consistent with the winter northeast monsoon. In particular, one peak of Chl-a concentrations was observed in December. Areas with higher Chl-a concentrations along the coast were observed in both winter and summer monsoon months. KEY WORDS: Phytoplankton blooms, Monsoon, Gulf of Thailand, El Nino

Download Full-text

Interactions territoriales, dynamique des usages et de la biodiversité dans les zones humides du delta du Rhône : une approche par la modélisation multi-agents (Territorial interactions, uses and biodiversity dynamics within the wetlands of Rhone river delta : a multi agent modelling approach)

Bulletin de l Association de géographes français ◽

10.3406/bagf.2003.2353 ◽

2003 ◽

Vol 80 (4) ◽

pp. 417-429

Author(s):

Raphaël Mathevet ◽

André Mauchamp ◽

Robert Lifran ◽

Brigitte Poulin ◽

Gaétan Lefebvre

Keyword(s):

River Delta ◽

Rhône River ◽

Rhone River ◽

Multi Agent ◽

Modelling Approach ◽

Multi Agents

Download Full-text

A mesohabitat method used to assess minimum flow changes and impacts on the invertebrate and fish fauna in the Rhône River, France

River Research and Applications ◽

10.1002/rra.997 ◽

2007 ◽

Vol 23 (5) ◽

pp. 525-543 ◽

Cited By ~ 15

Author(s):

Atle Harby ◽

Jean-Michel Olivier ◽

Sylvie Merigoux ◽

Emmanuel Malet

Keyword(s):

Fish Fauna ◽

Rhône River ◽

Minimum Flow ◽

Rhone River ◽

Flow Changes

Download Full-text

A biological Indian Ocean Dipole event in 2019

Scientific Reports ◽

10.1038/s41598-021-81410-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wei Shi ◽

Menghua Wang

Keyword(s):

Biological Activity ◽

Indian Ocean ◽

Indian Ocean Dipole ◽

Infrared Imaging ◽

Equatorial Indian Ocean ◽

The West ◽

Indian Ocean Dipole Event ◽

Chl A ◽

Positive Indian Ocean Dipole ◽

Dipole Response

AbstractThe 2019 positive Indian Ocean Dipole (IOD) event in the boreal autumn was the most serious IOD event of the century with reports of significant sea surface temperature (SST) changes in the east and west equatorial Indian Ocean. Observations of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP) between 2012 and 2020 are used to study the significant biological dipole response that occurred in the equatorial Indian Ocean following the 2019 positive IOD event. For the first time, we propose, identify, characterize, and quantify the biological IOD. The 2019 positive IOD event led to anomalous biological activity in both the east IOD zone and west IOD zone. The average chlorophyll-a (Chl-a) concentration reached over ~ 0.5 mg m−3 in 2019 in comparison to the climatology Chl-a of ~ 0.3 mg m−3 in the east IOD zone. In the west IOD zone, the biological activity was significantly depressed. The depressed Chl-a lasted until May 2020. The anomalous ocean biological activity in the east IOD zone was attributed to the advection of the higher-nutrient surface water due to enhanced upwelling. On the other hand, the dampened ocean biological activity in the west IOD zone was attributed to the stronger convergence of the surface waters than that in a normal year.

Download Full-text