Impacts of human interventions on the evolution of the Ria Formosa barrier island system (S. Portugal)

Geomorphology ◽  
2019 ◽  
Vol 343 ◽  
pp. 129-144 ◽  
Author(s):  
Katerina Kombiadou ◽  
Ana Matias ◽  
Óscar Ferreira ◽  
A. Rita Carrasco ◽  
Susana Costas ◽  
...  
Keyword(s):  
Barrier Island ◽  
Ria Formosa ◽  
Human Interventions ◽  
Island System

ASSESSMENT OF NATURAL AND ANTHROPIC DRIVERS TO THE EVOLUTION OF RIA FORMOSA BARRIER ISLAND SYSTEM

2019 ◽  
Author(s):  
KATERINA KOMBIADOU ◽  
ANA MATIAS ◽  
SUSANA COSTAS ◽  
A. RITA CARRASCO ◽  
ÓSCAR FERREIRA ◽  
...  
Keyword(s):  
Barrier Island ◽  
Ria Formosa ◽  
Island System

scholarly journals Holocene evolution of a barrier island system, Ria Formosa, South Portugal

The Holocene ◽  
2018 ◽  
Vol 29 (1) ◽  
pp. 64-76 ◽  
Author(s):  
Carlos Sousa ◽  
Tomasz Boski ◽  
Laura Pereira
Keyword(s):  
Seismic Refraction ◽  
Barrier Island ◽  
Color Variation ◽  
Present System ◽  
Middle Holocene ◽  
Accommodation Space ◽  
Ria Formosa ◽  
Age Model ◽  
Island System ◽  
South Portugal

Holocene evolution of the Ria Formosa barrier island system was studied through the examination of a large subsurface dataset acquired from 191 boreholes and five seismic refraction profiles. Two boreholes with total depths of 26 and 16.5 m were selected for a multi-proxy detailed laboratory analysis, including mean grain size distribution, organic matter (OM) content, color variation, shell identification, and benthic foraminifera assemblages. Selected cores are thought to be representative of the identified depositional sub-basins. Subsurface age data from 16 AMS 14C dated samples were plotted against depth and resulted in a coherent age model of sedimentary infill. The system evolution was largely controlled by sediment availability, accommodation space, and Holocene sea level rise, first at a rapid rate of 7 mm/yr from 10 kcal yr BP to 7.25 kcal yr BP, followed by a slowdown to 1.1 mm/yr until present. A conceptual model for the origin and Holocene evolution of the Ria Formosa barrier island system implies three main steps, leading to the present system geomorphology: (1) marine flooding of incised palaeovalleys by the rapid transgression of palaeovalleys in the early Holocene; (2) development of a proto-barrier island chain perched on Pleistocene detritic headlands and steeper interfluve areas during the early to middle Holocene; and (3) full development of the barrier islands chain and enclosing of the coastal lagoon, followed by the maturation of the system with subsequent siltation and salt marsh expansion from the middle Holocene until present. The onset of barrier system formation dates back to ca. 8 kcal yr BP, predating previously proposed age.

Salt marshes adjustment to anthropogenic pressures and sea-level rise

2021 ◽  
Author(s):  
A. Rita Carrasco ◽  
Katerina Kombiadou ◽  
Miguel Amado
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Salt Marshes ◽  
Anthropogenic Pressures ◽  
The Past ◽  
Ria Formosa ◽  
Sediment Loads ◽  
Human Interventions ◽  
South Portugal ◽  
And Sea Level

<p>It is predictable that salt marshes in regions, where sediment loads are high, should be stable against a broader range of relative sea level scenarios than those in sediment-poor systems. Despite extensive theoretical and laboratory studies, additional syntheses of marsh ‘persistence’ indicators under human interventions and accelerated sea-level rise rates are still needed. This study investigates the recent lateral changes occurring in lagoon-type marshes of the Ria Formosa lagoon (south Portugal) in the presence of human interventions and sea-level rise, to identify the major drivers for past marsh evolution and to estimate potential future trends. The conducted analysis assessed the past geomorphological adjustment based on imagery analysis and assessed its potential future adjustment to sea-level rise (~100 years) based on modelled land cover changes (by employing the SLAMM model within two sea-level rise scenarios).</p><p>Salt marshes in the Ria Formosa showed slow lateral growth rates over the last 70 years (<1 mm∙yr<sup>-1</sup>), with localized erosion along the main navigable channels associated with dredging activities. Higher change rates were noted near the inlets, with stronger progradation near the natural inlets of the system, fed by sediment influx pulses. Any potential influence of sea-level increase to an intensification of marsh-edge erosion in the past, could not be distinguished from human-induced pressures in the area. No significant sediment was exchanged between the salt marshes and tidal flats, and no self-organization pattern between them was observed in past. The related analysis showed that landcover changes in the salt marsh areas are likely to be more prominent in the future. The obtained results showed evidence of non-linearity in marsh response to high sea-level rise rates, which could indicate to the presence of critical thresholds and potential negative feedbacks within the system, with significant implications to marsh resilience.</p>

The Sedimentary Control of Accumulation of Coalbed Methane in Hancheng Coalbed Methane Field

2013 ◽  
Vol 295-298 ◽  
pp. 3350-3353
Author(s):  
Xiao Hong Wang ◽  
Da Meng Liu ◽  
Yan Bin Yao ◽  
Ying Li ◽  
Chen Xie ◽  
...  
Keyword(s):  
Coalbed Methane ◽  
Barrier Island ◽  
Lower Permian ◽  
Upper Carboniferous ◽  
Shallow Marine ◽  
Sedimentary Environments ◽  
Taiyuan Formation ◽  
Delta System ◽  
Island System

This paper discusses how sedimentary controls on accumulation of coal and coalbed methane in Hancheng CBM field. Two major coal-bearing strata include the Upper Carboniferous Taiyuan formation (a marine and terrestrial sedimentation) and the Lower Permian Shanxi formation (a terrestrial sedimentation). The favorable sedimentary environments for accumulation of coalbed methane by decreasing order are the shallow marine and barrier island system, the delta system, and the shallow marine and plane coast system.

scholarly journals Recent Evolution of the Natural Inlets of a Barrier Island System in Southern Portugal

2002 ◽  
Vol 36 ◽  
pp. 741-752 ◽  
Author(s):  
A. Vila-Concejo ◽  
A. Matias ◽  
Ó. Ferreira ◽  
C Duarte ◽  
J.M.A. Dias
Keyword(s):  
Barrier Island ◽  
Southern Portugal ◽  
Island System
Sign in / Sign up

Export Citation Format

Share Document