scholarly journals The Impacts of the Middle Holocene High Sea-Level Stand and Climatic Changes on Mangroves of the Jucuruçu River, Southern Bahia – Northeastern Brazil

Radiocarbon ◽  
2017 ◽  
Vol 59 (1) ◽  
pp. 215-230 ◽  
Author(s):  
Neuza Araújo Fontes ◽  
Caio A. Moraes ◽  
Marcelo C L Cohen ◽  
Igor Charles C. Alves ◽  
Marlon Carlos França ◽  
...  
Keyword(s):  
Organic Matter ◽  
Sea Level ◽  
Sedimentary Organic Matter ◽  
Northeastern Brazil ◽  
C3 Plants ◽  
Terrestrial Organic Matter ◽  
Stable Isotopic ◽  
Southern Bahia ◽  
Mangrove Dynamics ◽  
A Site

AbstractThe aim of this paper is to evaluate the compatibility between the Holocene relative sea-level (RSL) curves proposed for the Brazilian littoral and mangrove dynamics along a fluvial valley in the state of southern Bahia. This was done integrating geomorphological, sedimentological, palynological, and stable isotopic data from two cores collected at the mouth of the Jucuruçu River and at a site 23 km inland, near the city of Prado, northeastern Brazil. Core PR07, sampled from a fluvial plain at about 4.5±1 m above the RSL, reveals mangrove pollen (5–20%) and estuarine/terrestrial organic matter (δ13C=~–25‰, C/N=7.3–67) between 4.5 m (~7400 cal yr BP) and 1.75 m depth (~5350 cal yr BP). Core PR11, sampled from a mangrove tidal flat, also revealed mangrove pollen taxa (5-28%) since 660 cal yr BP. Core PR07 indicated absence of mangrove pollen and increase of sedimentary organic matter sourced from terrestrial C3 plants (δ13C=~–27‰, C/N=22–159) during the last 5350 cal yr BP. Probably, the changes in vegetation and sedimentary organic matter identified in core PR07 were caused by the combined effects of the RSL fluctuations, with a highstand at about 5350 cal yr BP of 2.7±1.35 m, and changes in fluvial discharge.

scholarly journals C and N elemental and stable isotopic signatures in sedimentary organic matter from Lake Pamvotis (Greece)

Geologija ◽  
2008 ◽  
Vol 51 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Polona Vreča ◽  
Constantine Stalikas ◽  
Gregor Muri ◽  
Victoria Daskalau ◽  
Tjaša Kanduč ◽  
...  
Keyword(s):  
Organic Matter ◽  
Sedimentary Organic Matter ◽  
Isotopic Signatures ◽  
Stable Isotopic ◽  
C And N

scholarly journals Evidence for the offshore transport of terrestrial organic matter due to the rise of sea level: The case of the East China Sea Continental Shelf

2000 ◽  
Vol 27 (23) ◽  
pp. 3893-3896 ◽  
Author(s):  
Kazumasa Oguri ◽  
Eiji Matsumoto ◽  
Yoshiki Saito ◽  
Makio C. Honda ◽  
Naomi Harada ◽  
...  
Keyword(s):  
Organic Matter ◽  
Continental Shelf ◽  
Sea Level ◽  
East China Sea ◽  
East China ◽  
The East China Sea ◽  
Terrestrial Organic Matter ◽  
China Sea ◽  
Offshore Transport

The tadpole of Dendropsophus haddadi (Bastos & Pombal 1996) (Hylidae: Hylinae)

Zootaxa ◽  
2012 ◽  
Vol 3476 (1) ◽  
pp. 86 ◽  
Author(s):  
RICARDO LOURENÇO-DE-MORAES ◽  
FELIPE SIQUEIRA CAMPOS ◽  
LUÍS FELIPE TOLEDO
Keyword(s):  
Central America ◽  
Sea Level ◽  
Atlantic Forest ◽  
Coastal Areas ◽  
The State ◽  
Northeastern Brazil ◽  
Small Species ◽  
Southern Mexico ◽  
Southern Bahia ◽  
Espirito Santo

The genus Dendropsophus Fitzinger, 1843 currently includes 92 species of hylid treefrogs distributed from South and Central America to southern Mexico (Frost 2011). Dendropsophus haddadi is a small species of this genus (male SVL 15–19 mm; female SVL 21–24 mm) that is allocated in the D. decipiens clade, part of the D. microcephalus group, together with other three species: D. berthalutzae, D. decipiens, and D. oliveirai (Faivovich et al. 2005; Frost 2011). This species was recorded in regions of ombrophilous Atlantic forest and scrubby restinga vegetation mainly in coastal areas between the state of Espírito Santo and Pernambuco, Brazil (Bastos & Pombal 1996; Amorim et al. 2009; Camurugi et al. 2010; Araújo-Neto et al. 2012), ranging from sea level up to 650 m of elevation (Peixoto & Pimenta 2004). In this paper, we described the tadpole of D. haddadi from a population from southern Bahia, northeastern Brazil.

The impact of Quaternary sea-level changes on the sedimentary organic matter of the Paraíba do Sul Deltaic Complex area, southeastern Brazil

2019 ◽  
Vol 95 ◽  
pp. 102274 ◽  
Author(s):  
Marcelo de A. Carvalho ◽  
Josiane B. Plantz ◽  
Thiago G. Carelli ◽  
Gustavo Santiago ◽  
Viviane S.F. Trindade ◽  
...  
Keyword(s):  
Organic Matter ◽  
Sea Level ◽  
Sedimentary Organic Matter ◽  
Southeastern Brazil ◽  
Sea Level Changes ◽  
The Impact

scholarly journals Distribution and degradation of terrestrial organic matter in the sediments of peat-draining rivers, Sarawak, Malaysian Borneo

2019 ◽  
Vol 16 (22) ◽  
pp. 4517-4533 ◽  
Author(s):  
Ying Wu ◽  
Kun Zhu ◽  
Jing Zhang ◽  
Moritz Müller ◽  
Shan Jiang ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Total Nitrogen ◽  
River System ◽  
Small Rivers ◽  
C3 Plants ◽  
Terrestrial Organic Matter ◽  
Diagenetic Alteration ◽  
Lignin Phenols ◽  
Malaysian Borneo

Abstract. Tropical peatlands are one of the largest pools of terrestrial organic carbon (OCterr); however, our understanding of the dynamics of OCterr in peat-draining rivers remains limited, especially in Southeast Asia. This study used bulk parameters and lignin phenol concentrations to investigate the characteristics of OCterr in a tropical peat-draining river system (the main channel of the Rajang and three smaller rivers: the Maludam, Simunjan, and Sebuyau) in the western part of Sarawak, Malaysian Borneo. The depleted δ13C levels and lignin composition of the organic matter indicates that the most important plant source of the organic matter in these rivers is woody angiosperm C3 plants, especially in the three small rivers sampled. The diagenetic indicator ratio, i.e., the ratio of acid to aldehyde of vanillyl phenols ((Ad∕Al)V), increased with decreasing mean grain size of sediment from the small rivers. The selective sorption of acid relative to aldehyde phenols might explain the variations in the (Ad∕Al)V ratio. Elevated (Ad∕Al)V values observed from the Maludam's sediments may also be attributed to source plant variations. The (Ad∕Al)V ratio appears to be related to the C∕N ratio (the ratio of total organic carbon to total nitrogen) in the Rajang and small rivers. In small rivers, a quick decline of C∕N ratios is a response to the slower modification of (Ad∕Al)V ratios due to better preservation of lignin phenols. An accumulation of lignin phenols with higher total nitrogen percentages (TN%) in the studied systems was observed. Most of the OCterr discharged from the Rajang and small river systems was material derived from woody angiosperm plants with limited diagenetic alteration before deposition and thus could potentially provide significant carbon to the atmosphere after degradation.

Variations in δ13C values of sedimentary organic matter since late Miocene time in the Indus Fan (IODP Site 1457) of the eastern Arabian Sea

2019 ◽  
Vol 157 (6) ◽  
pp. 1012-1021 ◽  
Author(s):  
Boo-Keun Khim ◽  
Jongmin Lee ◽  
Sanbeom Ha ◽  
Jingu Park ◽  
Dhananjai K. Pandey ◽  
...  
Keyword(s):  
Organic Matter ◽  
Late Miocene ◽  
Arabian Sea ◽  
Sedimentary Organic Matter ◽  
Marine Phytoplankton ◽  
Land Plants ◽  
Terrestrial Organic Matter ◽  
Underlying Assumption ◽  
Catchment Areas ◽  
Eastern Arabian Sea

AbstractA 1108.6 m long core was recovered at Site U1457 located on the Indus Fan in the Laxmi Basin of the eastern Arabian Sea during IODP Expedition 355. Shipboard examinations defined five lithologic units (I to V) of the lower Paleocene to Holocene sedimentary sequence. In this study, δ13C values of sedimentary organic matter (SOM) confirm the differentiation of the lithologic units and further divide units III and IV into two subunits (1 and 2). Based on the underlying assumption that the SOM is decided primarily by a mixture of marine and terrestrial origins, δ13CSOM values at Site U1457 provide information on the terrestrial catchment conditions since late Miocene time. Low δ13CSOM values from late Miocene to late Pleistocene times are similar (c. −22.0 ‰) for the most part, reflecting a consistent contribution of terrestrial organic matter from the catchment areas characterized by dominant C3 land plants. Significantly lower δ13CSOM values (c. −24.0 ‰) in Unit III-2 (∼8 to ∼7 Ma) might be due to a greater input of C3 terrestrial organic matter. The increase in δ13CSOM values at ∼7 Ma and the appearance of high δ13CSOM values (c. −18.0 ‰) within Unit III-1 (∼7 to ∼2 Ma) indicate that C4 biomass overwhelmed the terrestrial catchment environment as a result of enhanced terrestrial aridity in the Himalayan foreland. The three-end-member simple mixing model, estimating the relative contributions of SOM from terrestrial C3 and C4 plants and marine phytoplankton, supports our interpretation of the distribution of C3 and C4 land plants in the terrestrial catchment environment.

Climate, sea-level, and anthropogenic influences on coastal vegetation of the southern Bahia, Northeastern Brazil, during the mid-late Holocene

Geomorphology ◽  
2021 ◽  
pp. 107967
Author(s):  
Beatriz L. Figueiredo ◽  
Igor Charles C. Alves ◽  
Marcelo C.L. Cohen ◽  
Luiz C.R. Pessenda ◽  
Marlon Carlos França ◽  
...  
Keyword(s):  
Sea Level ◽  
Late Holocene ◽  
Northeastern Brazil ◽  
Coastal Vegetation ◽  
Anthropogenic Influences ◽  
Southern Bahia

Impact of land-sea organic matter fluxes on the ocean biogeochemistry during the Last Deglaciation

2021 ◽  
Author(s):  
Thomas Extier ◽  
Katharina Six ◽  
Bo Liu ◽  
Tatiana Ilyina
Keyword(s):  
Organic Matter ◽  
Carbon Cycle ◽  
Sea Level ◽  
Biogeochemical Cycle ◽  
Global Ocean ◽  
Last Deglaciation ◽  
Terrestrial Organic Matter ◽  
Heinrich Event ◽  
The Last Deglaciation ◽  
Ocean Carbon

<p>The Last Deglaciation (21-10 ka) is the most recent transition from a glacial to interglacial state. It is characterized by a pronounced sea level change of 95 m resulting in flooding of land areas and changes of coastlines. This period is also marked by several millennial events like the Heinrich Event 1 with diverse effects on sea level, oceanic circulation, climate and carbon cycle. In case of flooding of land surfaces during periods of sea level rise, carbon and nutrients stored in terrestrial organic matter in vegetation and soils are transferred to the ocean, potentially impacting the global ocean biogeochemical cycle and the uptake/release of CO<sub>2</sub> once being remineralized. Changes in the ocean biogeochemical cycles are also indirectly related to the poorly constrained stoichiometry and remineralization time-scales of terrestrial organic matter, which both differ from the well-known parameters for marine organic matter.</p><p>We present here the first coupled transient simulation over the Last Deglaciation using the global ocean biogeochemical model HAMOCC (HAMburg Ocean Carbon Cycle) as part of the paleo-version of the MPI-ESM (Max Planck Institute Earth System Model) to study the impact of terrestrial organic matter input on the ocean biogeochemical cycle and oceanic CO<sub>2</sub> fluxes during large sea level variations. This model version combines (1) a fully interactive adaptation of the ocean bathymetry with corresponding changes of the land-sea distribution, (2) a transient river routing and (3) the land-sea terrestrial organic matter transfer after flooding. Our simulation provides new insights on the land carbon inputs to the ocean carbon inventory (water column and sediment) due to flooding, with 170 GtC between 21-10 ka, of which 21.1 GtC and 36.8 GtC are within two 1000 years large freshwater discharge events (between 15-14 ka and 12-11 ka). These inputs of carbon rich material to the ocean during flooding events have however only a local effect on ocean CO<sub>2</sub> outgassing, the global ocean remaining a sink of CO<sub>2</sub>. To infer the response of CO<sub>2</sub> fluxes in this context, sensitivity experiments can be performed during the type of Heinrich event (15-14 ka) to evaluate and better constrain the terrestrial organic matter remineralization parameters.</p>

Sign in / Sign up

Export Citation Format

Share Document