Abundance and distribution of benthic foraminifera as indicators of the quality of the sedimentary environment in a subtropical lagoon, Gulf of California

2018 ◽  
Vol 130 ◽  
pp. 31-39 ◽  
Author(s):  
Adriana Gómez-León ◽  
Griselda M. Rodríguez-Figueroa ◽  
Evgueni Shumilin ◽  
Ana Luisa Carreño ◽  
Alberto Sánchez
Keyword(s):  
Benthic Foraminifera ◽  
Gulf Of California ◽  
Sedimentary Environment ◽  
Abundance And Distribution ◽  
Subtropical Lagoon

THE ABUNDANCE OF RECENT FORAMINIFERA IN SURFACE SEDIMENT OF AMBON BAY

2010 ◽  
Vol 2 (1) ◽  
Author(s):  
Suhartati M. Natsir
Keyword(s):  
Surface Sediment ◽  
Benthic Foraminifera ◽  
Sea Water ◽  
Planktonic Foraminifera ◽  
Sediment Characteristic ◽  
Abundance And Distribution

Foraminifera are generally live in sea water with various sizes. These organisms consist of planktonic and benthic foraminifera. Geological activity on plutonic and volcanic with vomiting magma is transpiring on, and then affects sedimentation and foraminiferal abundance of Ambon Bay. The study was determined to study the abundance and distribution of foraminifera based on the sediment characteristic of Ambon Bay. Sample collected in 2007 of Ambon Bay showed that only 29 samples of 50 samples containing foraminifera. The collected sediments have 86 species of foraminifera, consisting 61 species of benthic foraminifera and 25 species of planktonic foraminifera. The dominant benthic foraminifera in the surface sediment of Ambon bay were Amphistegina lessonii, Ammoniabeccarii,Elphidium craticulatum,Operculina ammonoides and Quinqueloculina parkery. The planktonic foraminifera that were frequently collected from the bay were Globorotalia tumida, Globoquadrina pseudofoliata, Globigerinoides pseudofoliata, Globigerinoides cyclostomus dan Pulleniatina finalis. Generally, the species dwelled as abundant on substrate sand, whereas the areas within substrate mud have no foraminifera lie on them. Keywords: Foraminifera, Abundance, Sediment, Ambon Bay

Optimization of the yield and quality of agar from Gracilariopsis lemaneiformis (Gracilariales) from the Gulf of California using an alkaline treatment

2008 ◽  
Vol 21 (3) ◽  
pp. 321-326 ◽  
Author(s):  
Javier Alejandro González-Leija ◽  
Enrique Hernández-Garibay ◽  
Isaí Pacheco-Ruíz ◽  
Julián Guardado-Puentes ◽  
Julio Espinoza-Avalos ◽  
...  
Keyword(s):  
Gulf Of California ◽  
Alkaline Treatment ◽  
Gracilariopsis Lemaneiformis ◽  
Yield And Quality

scholarly journals ORGANIC COMPOUNDS AS PROXIES OF THE SEDIMENTARY ENVIRONMENTAL QUALITY OF THE MARICÁ-GUARAPINA LAGOON SYSTEM (SE, BRAZIL)

2019 ◽  
Vol 4 (2) ◽  
pp. 159-173 ◽  
Author(s):  
Lazaro Laut ◽  
Maria Virgina Alves Martins ◽  
Pierre Belart ◽  
Maria Lucia Lorini ◽  
Iara Clemente ◽  
...  
Keyword(s):  
Organic Matter ◽  
Rio De Janeiro ◽  
Sedimentary Environment ◽  
Environmental Parameters ◽  
Geochemical Data ◽  
Fine Grained ◽  
Lagoon System ◽  
Se Brazil ◽  
Anthropogenic Contribution

Bottom sediment is a natural trap for organic matter and different kinds of pollutants. The accumulation of large amount of organic matter gives rise to the eutrophication of the aquatic ecosystems. The analyses of the quantity and quality of the organic matter (biopolymers) help to determine the trophic status of coastal ecosystems. The Maricá-Guarapina Lagoon System (MGLS) is located in Rio de Janeiro and is composed by four connected lagoons: Maricá, Barra, Padre and Guarapina. It has been suffering impacts due to the intense and uncontrolled property speculation. Based on this problem, this study aimed to characterize the organic matter (OM) amount and quality in sediments and the relation with the impacted areas in this lagoon system. The collected sediment samples were analyzed for geochemical data combined with grain size and physical-chemical environmental parameters of the bottom water. Statistical results evidenced that the sedimentary environment of the MGLS is heterogenous. The organic matter supplied to the MGLS is provided from different sources but the autochthonous contribution (phytoplanktonic productivity and vegetal detritus from the mangrove fringe) prevails. The anthropogenic contribution was more evident in Padre Lagoon, where the sediments had relatively low TOC contents (0.1-0.8%). The MGLS is accumulating mainly aged organic matter. The most impacted zones were found in Guarapina, Barra and Maricá lagoons, in bottoms of fine-grained sediments, with relatively high TOC and labile biopolymeric compounds (proteins, carbohydrates and lipids) contents, which should evolve into an ever-increasing stage of eutrophication. COMPOSTOS ORGÂNICOS USADOS COMO INDICADORES DA QUALIDADE AMBIENTAL SEDIMENTAR DO SISTEMA LAGUNAR MARICÁ-GUARAPINA (SE DO BRASIL)ResumoO sedimento de fundo constitui uma armadilha natural para a matéria orgânica e diferentes tipos de poluentes. O acúmulo de grande quantidade de matéria orgânica dá origem à eutrofização dos ecossistemas aquáticos. Estimativas de quantidade e qualidade da matéria orgânica (biopolímeros) podem ajudar a determinar o estado trófico dos ecossistemas costeiros. O Sistema Lagunar de Maricá-Guarapina (MGLS), localizado no Estado do Rio de Janeiro (SE do Brasil), é composto por quatro lagunas interconectadas: Maricá, Barra, Padre e Guarapina. Este sistema tem sofrido impactos devido à intensa e descontrolada especulação imobiliária. Neste contexto, este estudo teve como objetivo caracterizar a quantidade e qualidade de matéria orgânica (MO) dos sedimentos do MGLS. Foram obtidos dados geoquímicos e confrontados com resultados granulométricos em amostras de sedimentos coletados em 22 estações de amostragem e analisados parâmetros físico-químicos da água. Os resultados estatísticos evidenciaram que o ambiente sedimentar do MGLS é heterogêneo. Este sistema recebe matéria orgânica de diferentes fontes, sendo, porém, prevalecente a contribuição autóctone (produtividade fitoplanctônica e detritos vegetais dos manguezais existentes na região). A contribuição antropogênica de matéria orgânica foi mais evidente na Lagoa do Padre, onde os sedimentos apresentaram teores de COT relativamente baixos (0,1-0,8%). As zonas mais impactadas foram encontradas em fundos de sedimentos finos, com teores relativamente elevados de COT e de compostos biopoliméricos lábeis (proteínas, carboidratos e lipídios), nas lagunas de Guarapina, Barra e Maricá. Os resultados obtidos revelam também que o MGLS está acumulando principalmente matéria orgânica envelhecida e permitem prever que as referidas áreas podem evoluir para um estágio de cada vez maior grau de eutrofização.Palavras-chave: Lagunas Costeiras Tropicais. Biopolímeros. Eutrofização. Dinâmica Sedimentar.

Assessment of near-surface mapping capabilities by airborne transient electromagnetic data — An extensive comparison to conventional borehole data

Geophysics ◽  
2014 ◽  
Vol 79 (4) ◽  
pp. B187-B199 ◽  
Author(s):  
Cyril Schamper ◽  
Flemming Jørgensen ◽  
Esben Auken ◽  
Flemming Effersø
Keyword(s):  
Raw Materials ◽  
Sedimentary Environment ◽  
Poor Quality ◽  
Aquifer Vulnerability ◽  
Data Types ◽  
Borehole Data ◽  
Surface Mapping ◽  
Near Surface ◽  
Transient Electromagnetic

A newly developed helicopter transient electromagnetic (TEM) system has the ability to measure very early times within just a few μs after the turn off of the primary current. For such a system, careful calibration and accurate modeling of the electromagnetic (EM) response is critical to get true resistivities of the very shallow geologic layers. We discovered that this leads to resolution of the same level or in some cases even better than what can be obtained from airborne frequency EM systems. This allowed a range of important applications where high and accurate resolution is mandatory, e.g., geotechnical applications such as urban planning, railroad and road investigations, landslides or distribution of raw materials, and assessing aquifer vulnerability. We evaluated the results of a pilot survey covering the Norsminde catchment south of Aarhus, Denmark, where we found that near-surface layers (top 30 m) can be mapped with an accuracy of a few meters in a complicated glacial sedimentary environment. The mapping of the geologic layers was assessed by a detailed analysis in which we developed a general methodology for crosschecking the EM and borehole data. This methodology is general and can easily be adapted to other data types and surveys. After rating the quality of the boreholes based on a list of predefined criteria, we concluded that the EM data matched with about three-quarters of the boreholes located within less than 15 m from the closest EM soundings. The remaining quarter of the boreholes fell into two groups in which half of the boreholes were of very poor quality or had inaccurate coordinates. Only eight of all the boreholes could not be reproduced by the data, and we attributed this to be caused by very strong lateral or vertical geologic variations not resolvable by the TEM technique.

Benthic Foraminifera Across the Cretaceous/Paleogene Boundary in the Eastern Tethys (Northern Alborz, Galanderud Section): Extinction Pattern and Paleoenvironmental Reconstruction

2020 ◽  
Vol 50 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Masoud A. Rostami ◽  
Fabrizio Frontalini ◽  
R. Mark Leckie ◽  
Rodolfo Coccioni ◽  
Eric Font ◽  
...  
Keyword(s):  
Species Richness ◽  
Benthic Foraminifera ◽  
Oxygen Index ◽  
Major Change ◽  
Partial Recovery ◽  
Paleoenvironmental Reconstruction ◽  
The Third ◽  
Paleoenvironmental Changes ◽  
Abundance And Distribution ◽  
Depositional Setting

Abstract Extinction patterns, paleobathymetric inferences, and paleoenvironmental changes based on benthic foraminifera were investigated across the Cretaceous/Paleogene (K/Pg) boundary at the Galanderud section (Northern Alborz, Iran), which contains one of the most continuous and expanded K/Pg transitions in the eastern Tethys. On the basis of benthic foraminiferal taxa abundance and distribution, an outer neritic to uppermost bathyal paleo-depositional setting is inferred. In addition, benthic foraminiferal assemblages and planktic/benthic ratios do not indicate any major change in relative sea level during latest Maastrichtian-early Danian time. Changes in benthic foraminiferal assemblages, morphotypes, diversity, heterogeneity, and benthic foraminiferal oxygen index, coupled with statistical analyses, define three intervals. In the first interval (uppermost Maastrichtian Plummerita hantkeninoides Zone), benthic foraminiferal assemblages are moderately to well preserved and highly diverse, with a combination of epibenthic and endobenthic taxa indicating stable, mesotrophic to weakly eutrophic, normal marine conditions. A major change in benthic foraminiferal assemblages at the K/Pg boundary defines a second interval (basal Danian Guembelitria cretacea and lower part of Parvularugoglobigerina eugubina Zones) that is marked by a decrease in the endobenthic morphogroups as well as a decrease in diversity, heterogeneity, genus and species richness. This second interval denotes highly oligotrophic conditions and a collapse in productivity and food availability due to the extinction of some primary producers, with the exception of the three chalk beds representing short-lived blooms of calcareous dinoflagellates. Benthic foraminifera do not show significant extinction at the end of the Cretaceous at this section with only about an 8% loss of species. Additionally, the abundance of some opportunistic species, including Cibicidoides pseudoacutus and Tappanina selmensis, may reflect instability in the benthic foraminiferal assemblages. The third interval (middle-upper part of the Pv. eugubina Zone) is characterized by the dominance of epibenthic morphogroups (up to 70% of the assemblages) with a partial recovery of endobenthic groups. The characteristics of the benthic foraminiferal assemblages indicate that the flux of food to the benthos had not fully recovered during the early Danian.

Environmental forcing on the flux of organic-walled dinoflagellate cysts in recent sediments from a subtropical lagoon in the Gulf of California

2018 ◽  
Vol 621 ◽  
pp. 548-557 ◽  
Author(s):  
Tomasa Cuellar-Martinez ◽  
Rosalba Alonso-Rodríguez ◽  
Ana Carolina Ruiz-Fernández ◽  
Anne de Vernal ◽  
Lourdes Morquecho ◽  
...  
Keyword(s):  
Gulf Of California ◽  
Dinoflagellate Cysts ◽  
Environmental Forcing ◽  
Recent Sediments ◽  
Subtropical Lagoon

scholarly journals Composition of planktonic organisms and its associated physico-chemical parameters in two ponds at African regional aquaculture centre (ARAC) Aluu, Port Harcourt

1970 ◽  
Vol 21 (1) ◽  
pp. 1-5
Author(s):  
GN Woke ◽  
IP Aleleye-Wokoma
Keyword(s):  
Water Quality ◽  
Heavy Rainfall ◽  
Aquatic Organisms ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Port Harcourt ◽  
Dominant Classes ◽  
Abundance And Distribution ◽  
Plankton Communities

Composition of plankton communities in two ponds at African Regional Agriculture Centre (ARAC) Aluu, Port Harcourt was undertaken between May and June 2004, to assess the composition, relative abundance and distribution of plankton. The diversity of plankton was poor. Twenty-eight taxa representing four (4) families were recorded for phytoplankton while seventeen taxa representing four families were identified for zooplankton. Chlorophyta and Cladocera were the most dominant classes in phytoplankton and zooplankton in terms of abundance, constitute 13.0% and 17.1% respectively. The water quality of the ponds is evident by high temperature (28.80C), depth (57.5cm), transparency (42), dissolved oxygen (4.9mg/l) and low BOD of (1.4mg/l). The lower density of organisms could be partly attributed due to heavy rainfall which destabilize the surface water and substrate. Hence, extensive studies of the ponds where aquatic organisms are kept should be carried out to maintain proper utilization of ponds.KEYWORDS: Plankton, composition, communities richness, abundance.

scholarly journals Organic carbon rich sediments: benthic foraminifera as bio-indicators of depositional environments

2019 ◽  
Author(s):  
Elena Lo Giudice Cappelli ◽  
Jessica L. Clarke ◽  
Craig Smeaton ◽  
Keith Davidson ◽  
William E. N. Austin
Keyword(s):  
Organic Matter ◽  
Carbon Content ◽  
Benthic Foraminifera ◽  
Organic Content ◽  
Depositional Environments ◽  
Carbon Burial ◽  
Actual Change ◽  
Freshwater Inputs

Abstract. Fjords have been described as hotspots for carbon burial, potentially playing a key role within the carbon cycle as climate regulators over multiple timescales. Nevertheless, little is known about the long-term fate of the carbon that may become stored in fjordic sediments. One of the main reasons for this knowledge gap is that carbon arriving on the seafloor is prone to post-depositional degradation, posing a great challenge when trying to discriminate between an actual change in carbon deposition rate and post depositional carbon loss. In this study, we evaluate the use of modern benthic foraminifera as bio-indicators of carbon content in six voes (fjords) on the west coast of Shetland. Benthic foraminifera are sensitive to changes in carbon content in the sediments, and changes in their assemblage composition therefore reflect synchronous variations in the quantity and quality of carbon reaching the seafloor. We identified four environments based on the relationship between benthic foraminiferal assemblages and carbon content in the sediments: 1) Land-locked regions influenced by riverine/freshwater inputs of organic matter, namely the head of fjords with a restricted geomorphology; 2) Stressed environments with a heavily stratified water column and sediments rich in organic matter of low nutritional value; 3) Depositional environments with moderate organic content and mild or episodic current activity; 4) Marginal to coastal settings with low organic content, such as fjords with an unrestricted geomorphology. We conclude that foraminifera potentially provide a tool to disentangle primary carbon signals from post-depositional degradation and loss of carbon because of their environmental sensitivity and high preservation potential in the sedimentary record.

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