DigitUMa
Repositório Institucional da Universidade da Madeira
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Synergy between ground-based remote sensing instruments for retrieving microphysical-optical-radiative properties of atmospheric aerosols
Publication . Oliveira, Daniel Camilo Fortunato dos Santos; Sicard, Michaël; Rodríguez Gómez, Alejandro Antonio
The improvements in retrieving microphysical, optical, and radiative properties
of aerosols can contribute to more detailed local observations and research, support
local or global climate modeling and air quality forecasting, validate satellite
products, and contribute to public policies. This PhD thesis aims at achieving such
improvements through synergies between ground-based remote-sensing
instruments. The objectives are to (1) evaluate the potential of an inversion
algorithm, namely GRASP, for retrieving aerosol properties from the synergy
between a polarized Sun-sky-lunar photometer and a state-of-the-art
ACTRIS/EARLINET multi-wavelength lidar, and (2) estimate long-term aerosol
radiative effects by combining net radiative fluxes from pyranometers and Aerosol
Optical Depth (AOD) from photometers, and assessing GRASP’s ability to retrieve
such effects on a case-by-case basis. To achieve Obj. 1, sensitive tests (noise-free
and random noise retrievals) were performed with GRASP for several combinations
of ground-based observations, including polarization information as GRASP inputs,
for three aerosol scenarios in Barcelona, Spain. The sensitive tests showed that the
addition of the Degree of Linear Polarization (DoLP) improved the noise-free and
random-noise GRASP inversions, particularly under higher AOD. The gains were
most notable for the coarse mode of the optical properties, and for the coarse mode
of the Real Refractive Index. To achieve Obj. 2, a direct method was applied to
estimate spectral Aerosol Forcing Efficiency (AFE) and Aerosol Radiative Forcing
(ARF) for a 14-year database in Barcelona, Spain. The AFE-ARF estimations
confirmed a dominant cooling forcing over Barcelona, with the strongest cooling
effect caused by mineral dust, followed by urban/industrial-biomass burning and
mixed aerosols. Furthermore, the GRASP inversions with DoLP were more accurate
for the ARF, agreeing with the direct method in the high-AOD cases.
Assessing the extent and impact of plastic pollution in coral reefs
Publication . Vered, Gal; Shenkar, Noa
Despite the growing awareness of the harmful effects, the continuous increase in plastic
influx into natural environments still poses a constant threat, endangering unique marine
ecosystems such as coral reefs. These reefs, which are essential ecologically and sustain
livelihoods for over a billion people worldwide, face severe degradation due to
anthropogenic activities, climate change and the pervasive issue of plastic pollution. Plastic
enters the oceans through various land- and sea-based human activities, breaking down into
microplastics and releasing chemical additives into the environment. Marine plastic debris
has detrimental effects on corals, increasing their vulnerability to pathogens and causing
issues like entanglement, suffocation and the ingestion of microplastics, resulting in energy
loss. Additionally, plastic additives leaching into the environment can harm marine
organisms, with chemicals such as bisphenols and phthalates disrupting endocrine systems.
The primary motivation of my research was to address the main knowledge gaps identified
by the United Nations Environment Programme concerning plastic pollution in coral-reef
ecosystems. I achieved this by conducting controlled experiments and comprehensive field
surveys, seeking to understand the extent and impact of plastic pollution in coral reefs.
My research encompasses an examination of the effects of plastic additives on coral
reef organisms; the characterization of plastic debris levels in the Gulf of Aqaba; and an
exploration of plastic additives in coral-reef invertebrates residing on natural substrates
compared to those residing on plastic debris. The findings from my study contribute to the
development of a comprehensive understanding of marine plastic pollution and its
implications for coral-reef ecosystems.
In Chapter 1, I examine the reproductive products of four tropical coral-reef
invertebrates exposed to environmentally-relevant concentrations in seawater of four
prevalent plastic additives: dibutyl phthalate (DBP), dimethyl phthalate (DMP), 4
nonylphenol (4-NP) and bisphenol A (BPA), as well as to 10
3
higher laboratory
concentrations of these four plastic additives. The findings reveal that apart from the -NP on the settlement of the soft coral Rhytisma
fulvum, none of the other tested materials demonstrated a significant effect on the exposed
organisms at environmentally relevant concentrations in the seawater. Regarding the high
laboratory concentrations: the 4-gnificant negative effects on all the
success in the solitary ascidian Herdmania momus, up to its complete failure to reproduce;
ad a significant negative effect on planulae
settlement of the stony coral Stylophora pistillata. The study's findings demonstrate the
negative and selective effects of plastic additives on the development and reproduction of
coral-reef organisms; and, specifically, the significant effect found following exposure to
4-NP. Consequently, if we wish to fully understand the impact of these contaminants on
this endangered ecosystem, their actual concentrations within the living organism tissues
need to be determined in order to produce relevant risk assessments for brooding coral
species.
The Gulf of Aqaba in the northern Red Sea is considered a potential coral-reef refuge
from climate change. However, it is subjected to increasing levels of plastic contamination.
In Chapter 2, I characterized the levels of benthic plastic debris, microplastics and plasticizers within the coral
2 years. I found that concentrations of benthic plastic debris lay within the level of the
reported data from other tropical coral reefs, with boating and fishing debris comprising
the most abundant categories. Unlike other studies that have investigated the relationship
between depth and the extent of plastic pollution, I found that the deep mesophotic reefs
featured significantly higher levels of benthic plastic debris compared to the shallower
concentrations to those reported for the central Red Sea surface seawater, with none of the
studied plasticizers exceeding the limits of quantification. These findings provide an
important scientific database for developing regional policies and management strategies
for battling plastic pollution and making the reefs of the northern Red Sea a coral refuge
protected from both global and local anthropogenic stressors.
In Chapter 3, I explore the differences in the presence of plastic additives among coral
reef invertebrates, particularly by comparing organisms residing on natural substrates with
those on plastic debris. The connection between the occurrence of plastic additives in corals
and encrusting invertebrates residing on plastic debris has not been explored to date, nor
contrasted with those residing on natural substrates. My analytical approach involved
utilizing Accelerated Solvent Extraction (ASE), Gas Chromatography-Mass Spectrometry
(GCMS), and High-Performance Liquid Chromatography coupled to both UV and Mass
Spectrometry (HPLC/UV/MS). These methodologies were applied to explore the
occurrence of seven targeted plastic additives in samples of three prevalent coral-reef
invertebrate species: Stylophora pistillata, Rhytisma fulvum and Crella cyathophora,
collected from both a protected reef within a marine nature reserve and an adjacent reef
outside the reserve. The study not only scrutinized the presence of plastic additives but also
investigated potential patterns across various species, substrates and sites. My findings
revealed the widespread presence of plastic additives in 52% of the examined organisms,
encompassing all the studied species and substrates, with Dibenzylamine and bis (2
ethylhexyl) phthalate (DEHP) emerging as the only detected compounds. Statistical
analyses indicated no significant difference in their presence between the natural substrate
and plastic debris. However, a statistically significant difference was observed in pollution
levels between sites, with the protected reef site exhibiting lower contamination. Notably,
R. fulvum within the marine reserve demonstrated significantly reduced pollution levels
compared to its counterparts in the unprotected adjacent reef. This underscores the
protective role of marine reserves in mitigating the impact of chemical pollutants on coral
reef ecosystems. The findings from this research add to the growing body of evidence
regarding the widespread presence of plastic-related chemicals, and highlight the protective
role of marine reserves in mitigating the impact of chemical pollutants on coral-reef
ecosystems.
The data acquired and presented in my dissertation contribute to promoting a global
understanding of the extent and impact of plastic pollution on coral-reef ecosystems. They
provide essential support for the science-based management of marine plastic pollution
and, consequently, may play a crucial role in the preservation of coral reefs.
Virtual reality to promote adaptation to psychological responses after early pregnancy loss
Publication . Mendes, Diana Carolina Gonçalves; Cameirão, Mónica da Silva; Fonseca, Ana Dias da
Early pregnancy loss, affecting nearly a quarter of identified pregnancies, is generally
disenfranchising and can lead to persistent perinatal grief, depression, anxiety and post-traumatic
stress disorder. Regardless, professional mental health support is often lacking. Standalone
immersive virtual reality has the potential to address this healthcare deficit by tackling the
invalidation and isolation that these women typically experience. Therefore, this research aimed
to design, develop and validate AViR2, a standalone virtual reality tool to prevent negative post
loss mental health responses.
To address the unstudied landscape of early pregnancy loss in Portugal, this research
started with a nationwide online survey characterizing the psychological impact, needs and
medical and technological experiences of these women. Our survey showed that many still
experience clinical levels of perinatal grief and comorbidities up to a year post-loss, possibly
modulated by their satisfaction with healthcare and information provision. Further, a few already
resort to digital alternatives. It further highlighted the need for them to receive early attention to
avoid psychological complications. It also emphasized the importance of providing spaces for
them to validate and memorialize their loss, facilitating adaptation.
The development of AViR2 was informed by various experimental studies that defined the
design guidelines for key virtual reality features (environments, virtual agents, body swapping).
Results demonstrated that nature-realistic and fractal-based environments reduce stress, a
humanoid speaking agent promotes personal self-disclosure, and body-swapping for self
dialogue aids perspective-taking. All these elements were integrated into four modules: Emotion
Management, Accepting the Loss, Social Sharing and Adapting to the Loss; each of these offering
psychoeducation and two to three tasks to practice adaptive coping skills.
AViR2 was tested for usability and subsequently evaluated in a feasibility study with two
women who had suffered a loss within six months of participation. AViR2 yielded very good levels
of usability and resulted in a reliable reduction of perinatal grief symptoms in both participants
and of post-traumatic stress disorder symptoms in one of them. Qualitative data showed that
these improvements were connected to symbolic closure, creative expression, and emotional
disclosure promoted by the system.
Ultimately, this work fills a gap in the national clinical literature and advances validation
of digital therapeutic tools. It demonstrates that an evidence-based immersive virtual reality
intervention can promote psychological adaptation and facilitate coping for women who have
suffered an early pregnancy loss.
UV-filters from insular ocean-cities. Impact on the marine sustainability
Publication . Íñiguez Santamaría, Eva; Cordeiro, Nereida Maria Abano; Dinis, Ana Margarida Brites Caetano; Kaufmann , Manfred Josef
Organic ultraviolet filters (oUVFs) are synthetic chemical compounds widely used in industrial
applications and personal care products to protect human skin and materials from solar
radiation. Over recent decades, increasing demand for these products has resulted in a
substantial rise in production and consumption, leading to their release into the environment.
Despite widespread use, information on environmental concentrations, chemical behaviour,
spatial distribution, persistence, and potential adverse effects on marine organisms remains
limited. Consequently, oUVFs are classified as Contaminants of Emerging Concern. Coastal
ecosystems are particularly vulnerable to oUVF contamination due to intensified tourism and
recreational activities, which constitute the main direct input pathways through activities such
as swimming and bathing. Indirect pathways, including wastewater treatment plant effluents,
industrial discharges, and terrestrial runoff, also contribute to inputs to marine environments
and may influence their persistence and distribution. This doctoral thesis investigates the
distribution, accumulation, and persistence of oUVFs, as well as their potential trophic transfer,
using an oceanic island as a representative study scenario. This approach enables the
assessment of oUVF contamination across a spatial gradient from coastal zones to deep-sea
environments and across multiple trophic levels through the analysis of diverse marine
organisms. Results indicate that areas influenced by direct coastal activities exhibit higher
oUVF concentrations than locations affected by indirect sources. Sessile organisms, such as
macroalgae, were particularly vulnerable, displaying elevated concentrations in areas subjected
to higher anthropogenic pressure. Herbivorous species exhibited the highest diversity and
concentrations of oUVFs, consistent with greater exposure and bioaccumulation potential at
lower trophic levels. Similar patterns were observed at higher trophic levels, including pelagic
species such as skipjack tuna (Katsuwonus pelamis), bathypelagic species such as black
scabbardfish (Aphanopus carbo), and deep-diving cetaceans. While sperm whales (Physeter macrocephalus) showed higher concentrations, resident short-finned pilot whales
(Globicephala macrorhynchus) exhibited a higher frequency of occurrence. Furthermore,
oUVFs were more prevalent in water column compartments characterized by elevated organic
matter, including the surface microlayer associated with zooplankton communities, and the
deep-sea bottom, associated with black scabbardfish habitat. In contrast, highly mobile species
with broad vertical and horizontal distributions showed low or undetectable concentrations.
Among the analyzed compounds, OC, EHS, HMS, BDBDM, and DTS were the most
frequently detected, underscoring their persistence. Overall, this thesis demonstrates the
widespread distribution of oUVFs beyond coastal environments, their impact on commercial
species, and their accumulation in top predators. It also presents the first validated methodology
for detecting oUVFs in marine zooplankton and provides concentration data across multiple
species and habitats, thereby addressing critical knowledge gaps.
Co-designing companions in virtual natural environments for enhanced well-being: insights from dementia informal caregivers
Publication . Peres, Beatriz; Lopes, Daniel S; Jorge, Joaquim; Campos, Pedro F.; Rodrigues Jardim Rino Peres, Beatriz; Pereira Campos, Pedro Filipe; Campos, Pedro
Informal caregivers of family members with Alzheimer’s Disease
and Related Dementias (ADRD) perform an often difficult and emo
tionally demanding task. The combination of Virtual Natural Envi
ronments (VNEs) and some form of social interaction could help
meet some caregiver needs but remains unexplored. In this study,
we investigate how ADRD informal caregivers envision compan
ionship in the context of VR nature. Through co-design sessions
with 15 ADRD informal caregivers, the thematic analysis identified
four main themes: companionship needs, physical presence, vir
tual presence, and characteristics and behaviors. Diverse types of
companions were suggested, with a preference for empathetic, cred
ible, and authentic companionship. Design opportunities include
integrating physical and virtual companionship within VNEs. This
research highlights the importance of designing companions that
help caregivers feel understood. Considering informal caregivers’
perspectives is integral to developing interventions that effectively
address their emotional and social well-being.