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Significant socio-economic factors for local e-government development in Portugal
No full textIn this paper, we present an empirical study of local e-government in Portugal and an investigation of the socio-economic indicators that are most significant to explain its development. The websites of all Portuguese municipalities were analysed according to three dimensions: government information, service delivery and participation. The results were investigated using regression models to identify the socio-economic indicators that are most significant to explain development and clustering techniques to identify homogeneous groups of municipalities in what concerns that development. We identify the socio-economic factors that are most significant to explain the results of municipalities and the discriminating factors for development in each dimension of analysis. We also identify seven main profiles of municipalities with different median scores in the three dimensions, which allow us to validate our own methodology and, generically, the ordered stages paradigm of the majority of the existent e-government maturity models. © 2013 Inderscience Enterprises Ltd
Administrative modernisation and e-government: the case of Águeda
No full textA major goal of governments today is to provide quality services, being their biggest challenge to implement tools that meet citizens' needs. For many years, the various levels of public administration, including municipalities, worked in a bureaucratic logic, making it difficult to provide services of excellence. E-government tried to overcome this problem. This article will analyse the impacts of administrative modernisation in a Portuguese municipality, Águeda, based on documentary analysis and interviews to senior officials of that municipality. © 2013 AISTI
A complex picture of associations between two host mussels and symbiotic bacteria in the Northeast Atlantic
No full textAmong chemosymbiotic metazoans found at deep-sea hydrothermal vents, cold seeps and organic falls, members of the mussel clade Bathymodiolinae (Bivalvia: Mytilidae) have evolved interactions with a higher diversity of bacterial lineages than other bivalve groups. Here, we characterized the bacteria associated with "Bathymodiolus" mauritanicus and Idas-like specimens from three sites in the Northeast Atlantic (two mud volcanoes in the Gulf of Cadiz and one seamount of the Gorringe Bank). Phylogenetic analysis of bacterial 16S rRNA-encoding gene sequences demonstrated that "B". mauritanicus has a dual symbiosis dominated by two phylotypes of methane-oxidising bacteria and a less abundant phylotype of a sulphur-oxidising bacterium. The latter was the dominant phylotype in a sympatric population of Idas-like mussels at the Darwin mud volcano. These results are the first report of a bacterial phylotype shared between two deep-sea mussels from divergent clades. This sulphur-oxidising bacterium was absent from Idas-like specimens from the other two sites (Gorringe Bank and MeknSs mud volcano), in which bacterial clone libraries were dominated by other Gammaproteobacteria related to symbionts previously identified in Idas modiolaeformis from the Eastern Mediterranean. All Idas-like specimens studied herein are closely related and also related to I. modiolaeformis. However, they probably display different associations with bacteria, with the possible absence of both methane- and sulphur-oxidising symbionts at the Gorringe Bank. These results draw a very complex picture of associations between mussels and bacteria in the Northeast Atlantic, which could be highly variable depending on locale characteristics of the habitats
Tidal and subtidal propagation in two Atlantic estuaries: Patos lagoon (Brazil) and Ria de Aveiro lagoon (Portugal)
No full textProcesses affecting the exchanges between lagoons and the adjacent inner continental shelf are controlled by tidal
and subtidal oscillations. Patos and Ria de Aveiro are coastal lagoons located on the southeast coast of Brazil and
northwest coast of Portugal, respectively. In the Patos Lagoon the tidal regime is micro-tidal and the local and nonlocal
wind forcing dominate the hydrodynamics, while in the Ria deAveiro lagoon tides are meso-tidal and represent
the main forcing. The main purpose of this study is to compare the propagation of tidal and subtidal oscillations
throughout the access channel of the Patos Lagoon and the main channels of Ria de Aveiro Lagoon. Predicted time
series of sea surface elevation (SSE) were obtained through modelling experiments for Patos Lagoon, while
measurements of SSE were carried out in several stations distributed along the main channels of the Ria de Aveiro
Lagoon, providing the data for this comparative study. The SSE time series were high-pass/low-pass filtered and the
propagation of tidal and subtidal oscillations was estimated for both lagoons by shifting from the time domain into
the frequency domain and applying spectral and cross-spectral analysis to the filtered SSE time series. Results
indicate that tidal and subtidal oscillations are differently attenuated in these lagoons due to the different local and
non-local forcing and to the morphology of the lagoons. This study also indicates that the proposed method is an
efficient and alternative way of estimating tidal and subtidal attenuation in both micro- and meso-tidal coastal
lagoons
Bioaccumulation and biochemical markers in feral crab (carcinus maenas) exposed to moderate environmental contamination: the impact of non-contamination-related variables
No full textModerate contamination is a challenging scenario for ecotoxicologists because of the occurrence of subtle biomarker responses and the increased relevance of non-contamination related variables.
This investigative biomonitoring study was performed in a moderately contaminated coastal system (Óbidos lagoon, Portugal) to examine winter–summer variations on biochemical responses and accumulated metals in
Carcinus maenas
, searching for associations with environmental and biological factors.
Males and females were collected in three sites: Barrosa (BB) and Bom-Sucesso (BS) in upper lagoon, and
the middle lagoon (ML), closer to the lagoon inlet. Water and sediment were monitored for metals (Cu, Mn,
Ni, Cr, Cd). Catalase (CAT), glutathione peroxidase (GPx), glutathione
S
-transferase (GST), total glutathione
content (GSH
t
), lipid peroxidation (LPO), and ethoxyresorufin-
O
-deethylase (EROD), as well as Cu, Mn, Ni,
Cr and Cd were measured in the crabs’ hepatopancreas. Inter-site differences, though infrequent, pointed
to the presence of crab stressors at BB. This was particularly obvious in summer when higher GSTas well
as lower GSH
t
and EROD were found in females, and accompanied by higher Ni accumulation. Seasonal
differences of biochemical responses superimposed spatial variations in line with the contrasting winter–summer conditions regarding water quality and, to a lesser extent, with metal bioaccumulation. CAT, GSH
t
,
and LPO were higher in summer, whereas enhancements of GPx and GSTwere recorded in winter. Winter
increases were in agreement with higher availability of metals in water and enhancement of accumulated
levels, particularly in females as emphasized by a bioaccumulation index. On the other hand, increases in
summer were mainly driven by non-contamination related factors. Males and females exhibited different
patterns of metal accumulation and biochemical responses, with females being more responsive, as confirmed by a general stress index (IBR). Results recommend gender separation in biomonitoring programs
using crabs. The integration of biochemical responses into IBR substantiated data interpretation. This is
particularly relevant under moderate contamination allowing for better site-distinction rather than biochemical responses considered individually
Trends of bathymetric variations at a tidal inlet
No full textThis work aims at establishing the trends of erosion and deposition in the
Ria de Aveiro
inlet
and surrounding area. Bathymetric changes were evaluated through two different methodologies: analysis of
bathymetric field data and results from numerical modeling. The numerical results of bathymetric changes
obtained show deposition trends at the centre of the navigat
ion channel, and erosion close to the north jetty.
These erosion trends show that the stability of the part of the north jetty located in the inlet might be threatened.
The comparisons of the numerical results with the observed data allow establishing the performance of the model
in simulating bathymetric variations for the period under study
Evaluation of single waves effects on the morphology evolution of a coastal lagoon inlet
No full textIn morphodynamic simulations of coastal lagoons should be
included the several processes that contribute to
sediment transport and consequently to bathymetric cha
nges. The individual contribution of the tidal currents,
waves, wind and rivers disc
harge should be considered to better characterize the study area evolution. In the
work presented herein, an evaluation of single wave effects on the bathymetric changes of a coastal inlet is
presented, by neglecting the forcing of wind and rivers
discharge in the numerical simulations and filtering the
changes produced by the tidal currents. The bathymet
ric changes, the residual sediment fluxes and the
sedimentation rates induced by eight monochromatic waves
at the inlet were analyzed. It was concluded that the
influence of the simulated waves on the morphodynamics
is restricted to the inlet and adjacent nearshore.
Additionally, the changes in the bathymetry and residual sediment transport are strongly dependent on the wave
height forcing rather than on their frequency of occurrence. These conclusions emphasize the importance of
independently analyze each wave, to better understand its impact in coastal systems dynamics
Composition and distribution of zooplankton across an upwelling front on the northern Portuguese coast during summer
No full textZooplankton was sampled during the summer of 1995 from a grid of 34 shelf stations located off the Ria de
Aveiro (northwestern Portugal), which were arranged into cross-shore transects extending either to the
shelf break or to the 50 m isobath. At each station, a bongo net was hauled obliquely from close to the
bottom or a maximum depth of 50 m to the surface. STD casts were made also at each station and wind
data were obtained from a land station. Analysis of salinity and temperature data detected the presence of
strong thermohaline stratification and a lens of reduced salinity water at the surface. A well-defined front,
located at a depth of 10 to 35 m, separated cold water close to shore from warmer offshore water.
Isopycnals between the front and the shore were bent towards the surface. The structure of the thermo-
haline features was consistent with the upwelling-favourable winds measured during the sampling period. A
classification and a multivariate analysis of variance of the more abundant species showed the presence of
two distinct assemblages that were separated by the front, indicating that these formations are important
features structuring the zooplanktonic community of upwelling areas. The data further indicate that the
zooplankton was composed of Palaeartic Atlantic and Mediterranean neritic species, and that oceanic
species were absent from the samples. The absence of oceanic species is interpreted as resulting from the
offshore displacement of the slope poleward flow and of the Portugal Current that takes place during the
summer, as a response to upwelling-favourable winds
The circatidal rhythm of the estuarine gastropod Hydrobia ulvae (Gastropoda: Hydrobiidae)
No full textIntertidal animals display a suite of cyclic behaviours that evolved as adaptations to the predictable cycle of
inundation and exposure. In estuarine habitats, mud snails from the genus
Hydrobia
are among the most abundant
grazers, and have received considerable attention with respect to the behavioural mechanisms mediating locomo-
tion, dispersal, and feeding, although the nature of the control of these processes has remained elusive. In
particular, it is not clear whether endogenous activity patterns are related to periodic changes of microphyto-
benthos biomass at the sediment surface, or whether they are timed to the tidal cycle at all. In the present study,
we address the crawling activity of
Hydrobia ulvae
under constant conditions, as well as the effects of individual
size and previous short-term exposure to tides of different range, by recording immersed individual snails under
constant dark conditions. We show that the species displays an overt circatidal pattern of crawling, with activity
peaks around high water, and that the start of inundation may act as an entrainment agent of the rhythm.
Moreover, the results obtained indicate that smaller snails display higher levels of activity, although neither the
size nor previous
in situ
influence of tidal range has an effect on the period and on the amplitude of the rhythm.
These findings suggest that fluctuations of microphytobenthos biomass are not a sufficiently strong selective
pressure to have shaped locomotor activity in
H. ulvae
. Moreover, feeding of
H. ulvae
should take place mostly
during high water and be independent of periodic fluctuations of microphytobenthos biomass at the surface of the
sediment
Geochemical associations and their spatial patterns of variation in soil data from the Marrancos gold-tungsten deposit: a pilot analysis
No full textThis paper discusses the results of a soil geochemical exploration survey in the environs of the Marrancos gold-tungsten deposit, dealing with 144 samples of topsoil, analysed for 53 chemical elements. At this initial stage of the project the main objectives were: (1) to identify associations between chemical elements; (2) to estimate spatial patterns of variation for such associations in the surficial materials. The associations were established using principal component analysis (PCA). Variography was used to obtain the theoretical model of spatial continuity of each variable. These models were used in the interpolation method (kriging) selected to estimate surficial dispersion patterns. The results of PCA and PCA mapping indicate distinct distribution patterns for the metals related to the primary mineralogical or geochemical association, as identified for this deposit. Based on the results, six of the 53 chemical elements studied were selected to estimate spatial patterns of dispersion in the topsoil. This approach allows the recognition of the geochemical signature of the deposit, and the selection of several target areas for follow-up work. Several sites were selected for water sampling (surficial and groundwater), and the soil samples to be used in partial extractions are now defined