A. Rita Carrasco

Universidade do Algarve | UALG · Centro de Investigação Marinha e Ambiental (CIMA)

Coastal vegetated ecosystems are major organic carbon (OC) and total nitrogen (TN) sinks, but the mechanisms that regulate their spatial variability need to be better understood. Here we assessed how superficial sedimentary OC and TN within intertidal vegetated assemblages (saltmarsh and seagrass) vary along a flow gradient, which is a major driver...

It is rational to assume that salt marshes in regions where sediment loads are high should remain stable or prograde when facing a range of sea-level scenarios, whereas those in sediment-poor systems may erode or drown. Despite extensive theoretical and laboratory studies, additional marsh ‘persistence’ indicators under human pressures and accelera...

From an ecological and socio-economic perspective, salt marshes are one of the most valuable natural assets on Earth. As external pressures are causing their extensive degradation and loss globally, the ability to monitor salt marshes on a long-term scale and identify drivers of change is essential for their conservation. Remote sensing has been de...

One of the key questions about wetlands resilience to sea-level rise is whether sediment supply will be enough to keep them coping with growing inundation levels. To address this question, researchers have put a lot of effort into field data collection and ecogeomorphic modelling, in an attempt to identify the tipping points of marsh survival. This...

Tidal coastal wetlands, common home to seagrass and salt marshes, are relevant carbon sinks due to their high capacity to accumulate and store organic carbon in their sediments. Recent studies demonstrated that the spatial variability of this organic carbon within the same wetland system can be significant. Some of the environmental drivers of this...

Despite being considered one of the most pressing global issues, biodiversity loss and the degradation of ecosystems is continuing at an alarming rate. In December 2022, COP15 saw the adoption of the Kunming-Montreal Global Biodiversity Framework, where four overarching international goals for biodiversity and 23 targets. While these targets are a...

Sustainability is a universal goal that requires balancing social, economic and environmental dimensions, and that applies to both terrestrial and marine environments. Several authors argue that arts are valuable tools to frame and engage with current environmental issues related to sustainability, including pollution, climate change and biodiversi...

The EGU Biodiversity Task Force welcomes the ambitious targets outlined in the Nature Restoration Law that was presented by the European Commission on 22 June 2022. The Nature Restoration Law's binding targets to restore degraded terrestrial land and marine ecosystems across the EU is a positive step for biodiversity and will enable the EU to take...

Coastal vegetated ecosystems such as saltmarshes and seagrasses are important sinks of organic carbon (OC) and total nitrogen (TN), with large global and local variability, driven by the confluence of many physical and ecological factors. Here we show that sedimentary OC and TN stocks of intertidal saltmarsh (Sporobolus maritimus) and seagrass (Zos...

The present study is a short provocative looking at stakeholders' views in the dimensions of ecosystem services in a global environmental change context. The work is based on a regional survey and intents to examine the perceptions of stakeholders of the Ria Formosa lagoon about salt marshes value. Results are part of an ongoing study about wetland...

Natural sciences have traditionally been disseminated in outreach activities as formal, one-way presentations. Nevertheless, innovative strategies are being increasingly developed using arts, gaming, and sketching, amongst others. This work aimed at testing an alternative and innovative way to engage non-expert audiences in ocean and coastal geolog...

Applying the ecological resilience principles to barrier island geomorphological evolution requires approaches that perceive and interpret resilience far from predefined barrier characteristics and static views. Accepting that barrier islands, like all natural systems, are dynamic and adaptively changing in response to external disturbances is fund...

Natural sciences have traditionally been disseminated in outreach activities as formal one-way presentations. Nevertheless, innovative strategies are being increasingly developed using arts, gaming, sketching, amongst others. This work aimed at testing an alternative and innovative way to engage non-expert audiences in ocean and coastal geology, th...

Resilience has been used over a wide range of scientific fields and often ambiguously, causing confusion over terminology and concepts and giving rise to distinct interpretations and misconceptions, even within the same scientific discipline. Starting by providing clarifications and definitions of the main terminology and key principles of ecologic...

Overwash hydrodynamic datasets are mixed in quality and scope, being difficult to obtain due to fieldwork experimental limitations. Nevertheless, these measurements are crucial to develop reliable models to predict overwash. Aiming to overcome such limitations, this work presents accurate fieldwork data on overwash hydrodynamics, further exploring...

Human interventions on sandy barriers interfere strongly with natural barrier dynamics, to the extent of having become key moderators of geomorphological evolution. This work identifies and analyses natural and human-induced drivers and their importance to the multi-decadal evolution of a barrier system. The methodology, based on aerial photograph...

Introduction: The increase in the frequency of extreme atmospheric conditions and of the global sea-level rise (SLR) rate is now an established fact (IPCC, 2013). Coastal evolution forced by SLR and storms involve phenomena such as the increased inundation of low-lying lands, shoreface and coastline erosion, displacement of natural habitats and sed...

Aerial photographic data and historical maps were used to identify trends, growth patterns and responses to anthropogenic disturbances in the barriers of the Ria Formosa system (South Portugal). Hard (inlet stabilizations, jetties) and soft (nourishments, inlet relocations) coastal works have influenced, to different extents, the recent (1952-2014)...

A number of previous research studies have addressed the enormous role played by biodiversity and ecosystems in human well-being and have placed particular emphasis on the consequences of the reduction or loss of these services. A handful of studies have implemented practical methodologies to quantify the variability of limiting factors leading to...

The services of a coastal ecosystem are critical to the functioning of the Earth’s life-support systems, and they are intimately governed by biotic and geologic couplings. This work assesses the temporal evolution of salt marsh ecosystems in a coastal lagoon, Ria Formosa lagoon, and analysis its triggering processes, both natural processes and huma...

The aim of the present paper is to analyse the recent morphological evolution of the sandy barriers of Ria Formosa, a multi-inlet system located in South Portugal, to assess evolution regimes and related controlling factors and to identify resilience mechanisms in response to natural and artificial drivers of change. The data collected comprise aer...

This study evaluates the patterns and effects of relative sea-level rise on the tidal circulation of the basin of the Ria Formosa coastal lagoon using a process-based model that is solved on an unstructured mesh. To predict the changes in the lagoon tidal circulation in the year 2100, the model is forced by tides and a static sea level. The bathyme...

The present paper contributes to assessing the resilience of a complex barrier island environment, namely of the Ria Formosa multi-inlet system in southern Portugal. The long-term morphologic evolution of four study areas during the last 60 years (1947 to 2014) is analysed based on aerial photographs, including the environments of oceanic and backb...

Overwash hydrodynamics datasets are mixed in quality and scope, being hard to obtain due to fieldwork experimental difficulties. Aiming to overcome such limitations, this work presents accurate fieldwork data on overwash hydrodynamics, further exploring it to model overwash on a low-lying barrier island. Fieldwork was performed on Barreta Island (P...

Overwash hydrodynamics were measured during a storm event. Data from literature and fieldwork were used to setup a numerical model, using XBeach in non-hydrostatic mode. Different simulations were conducted to assess the influence of several factors on overwash statistics. Nearshore morphology was found to greatly influence overwash. Sediment mean...

The present paper focusses on the objectives and methodology of the EVREST project regarding the identification of natural mechanisms that promote resilience in barrier island systems, both in oceanfront and backbarrier environments. The study area of the project is the Ria Formosa barrier island system, located in southern Portugal.

A major concern of coastal engineering is not only to access the damage to coastal structures by severe wave overtopping, but also the hazard imposed to users. Local hazard is often associated to the volume of overtopping water per unit of time (called overtopping discharge). Despite two decades of intensive research, it is yet not fully clear to p...

A major concern of coastal engineering is not only to access the damage to coastal structures by severe wave overtopping, but also the hazard imposed to users. Local hazard is often associated to the volume of overtopping water per unit of time (called overtopping discharge). Despite two decades of intensive research, it is yet not fully clear to p...

Accurate prediction of the occurrence and morphological consequences of overwash are important for coastal flood risk assessment and management. A number of morphological and oceanographic factors controlling overwash have been identified by several authors, including nearshore bathymetry. This work intends to identify alongshore variations in stor...

Overwash prediction is very important for coastal zone management. This work intends to identify alongshore variations in storm impact and evaluate the role of sub-aerial and submerged morphologies in overwash occurrence. For this study, 24 cross-shore topo-bathymetric profiles were set on Barreta Island (Ria Formosa barrier island system, Portugal...

This study investigates sediment transport at a very low-energy backbarrier beach in southern Portugal, from a spring-to-neap tide period, during fair-weather conditions. Rates and directions of transport were determined based on the application of fluorescent tracer techniques. Wind and currents were collected locally, whereas the dominant small a...

There is little unanimity concerning the environmental modifications potentially forced by the acceleration of global climate change in the coming century, or the future actions required to work towards a sustainable development of natural habitats in the coastal zone. A simple framework to assess the potential implications of flooding in fetch-lim...

This article defines short-term (tidal cycle) sediment-transport patterns at a backbarrier beach based on detailed field studies. Fieldwork was planned to record nonstorm, spring tide conditions that enable the definition of background sediment dynamics at the study area. The experiment was set at two beach morphologies: beach face and sandbank. Cu...

This study reports the medium-term evolution of a sandy backbarrier and its relation with prevailing wind conditions. Obtained results demonstrated that Ancão backbarrier does not behave as a scale-down version of higher energy fetch-limited or oceanic beaches, being considered as a low-energy beach with extremely low wind-induced wave conditions....

Sediment transport studies are useful tools for the determination of sediment budgets, important in the definition of management policies, in particular in environments not fully understood like fetch-limited beaches. Only a few studies have been made with respect to these beaches, and research efforts need to be continued to correctly quantify the...

Sandy beaches can be found in fetch-limited environments that are protected from ocean generated waves, as estuaries, lagoons, and backbarriers, and where fetch characteristics allow local wind-generated waves to develop and maintain a beach. The morphodynamics of these low-energy beaches present a peculiar behaviour and general open-ocean models a...

Profile characteristics of low energy sandy beaches include narrow foreshores that are often steep, with reflective swash zones. Seaward of the foreshore a low gradient terrace is generally present, acting as a wave energy filter. Low magnitude changes are usually associated to this type of environments, either cross- or longshore. To examine the s...

Profile characteristics of low energy sandy beaches include narrow foreshores that are often steep, with reflective swash zones. Seaward of the foreshore a low gradient terrace is generally present, acting as a wave energy filter. Low magnitude changes are usually associated to this type of environments, either cross- or longshore. To examine the s...

Shorelines occurring along restricted fetch environments, such as the backsides of barrier islands, are extremely diverse with respect to their morphologic characteristics and evolution. In order to better understand the morphodynamic evolution of backbarriers and the associated implications for entire barrier systems, this study proposes a backbar...

Management of the interactions between social/economic interests and the coastal environment requires practical, interdisciplinary assessment techniques. Backbarrier systems are critical natural resources that provide both economic and social benefits. Activities such as aquaculture, fishing, shipping and port activities, sediment mining, salt extr...

The shoreline changes along the backbarrier of a barrier system are extremely variable and critically dependent upon geographic location and the inherent interaction with hydrodynamic processes. There are only a few studies describing the backbarrier morphodynamic evolution and inherent implications to the entire barrier system. In the present stud...

The coastal stretch of Boca do Rio, western Algarve, Portugal, is experiencing shoreline retreat. Roman ruins are located along the beach section of the coast, and a 17th-century fort is positioned over the cliff section. Both historic monuments are being destroyed by erosion but need to be protected due to their heritage status. Aerial photograph...

Uncontrolled dredging in complex environments such as barrier island systems can produce major changes in inlet conditions, current circulations patterns and modify channel margins, leading to silting or erosion. This paper presents a study of the evolution of Faro Channel between 1927 and 2001, in the Ria Formosa barrier island system, taking into...

Inlet opening greatly modify the nearshore and bay morphology, as well as both updrift and downdrift shorelines. This paper analyses the evolution of the downdrift coast as response to the opening and stabilisation of an inlet at south Portugal. The inlet opening and stabilisation was responsible by two major effects on the downdrift coast: (1) dra...