42 research outputs found
Assessment of habitat and water quality of the Portuguese Febros River and one of its tributaries
A physical, chemical and biological characterisation of river systems is needed to evaluate their ecological quality and establish restoration programs. Aquatic benthic macroinvertebrates have proven to be among the most reliable and cost-effective assessment tools for water and habitat quality in streams throughout the world. During one year of seasonal surveys, the state of the Febros River and one of its tributaries, Jaca Creek, were evaluated in terms of habitat, physical, chemical and biological water quality, using benthic macroinvertebrates as ecological indicators. These watercourses suffer pollution from agriculture, industry and urban areas. Both watercourses were moderately to severely degraded, showing spatial and temporal variability in macroinvertebrate communities and water quality. The overall poor river conditions were particularly bad in the upper part of Jaca Creek, which is affected by industry. This upriver site showed higher temperatures, conductivity and dissolved solids than all other sites studied. The best conditions were found in the Gaia Biological Park area, where the habitat quality was evaluated to be high and biotic indices indicated excellent and good water quality in the spring and summer, respectively. However, even this site had biological indicator scores denoting severe degradation in autumn and winter. Macroinvertebrate diversity was low, with populations dominated by pollution-tolerant taxa like Chironomids, particularly in the summer and autumn samples. Abundances were mostly higher in the spring and lower in winter. Percentages of Ephemeroptera and Trichoptera (EPT) were low (totalling 31% on average), and Plecoptera was completely absent in the samples. The EPT percentage and the percentage of Chironomidae were related to temperature and Biochemical Oxygen Demand (BOD). In comparison to earlier studies, the Febros River improved in both habitat and biological quality. The present study should help to identify specific measures necessary to restore habitat and water quality to reference conditions.Para evaluar la calidad ecológica de un río y establecer programas de recuperación es necesaria una caracterización física, química y biológica de los sistemas fluviales. Los macroinvertebrados acuáticos bentónicos se encuentran entre las herramientas más fiables y efectivas para la estimación de la calidad del agua y los hábitats en aguas corrientes de todo el mundo. El estado del río Febros y uno de sus tributarios, la Ribeira de Jaca, han sido evaluados durante un año de controles estacionales en términos de hábitat y de la calidad física, química y biológica de sus aguas, mediante el uso de macroinvertebrados bentónicos como indicadores ecológicos. Estas cuencas fluviales están afectadas por la contaminación que procede de la agricultura, de la industria y de las áreas urbanas. Ambas corrientes de agua están de moderada a severamente degradadas, con variabilidad temporal y espacial de las comunidades de macroinvertebrados y de la calidad del agua. Las malas condiciones generales de la zona fluvial estudiada son especialmente aparentes en la parte alta de Ribeira de Jaca que está afectada por instalaciones industriales. Este punto presenta temperaturas, conductividades y sólidos disueltos más elevados que en los demás lugares estudiados. Las mejores condiciones se hallaron en el área del Parque Biológico de Gaia, donde el hábitat se puede evaluar como bueno y los índices bióticos indican que la calidad del agua es excelente y buena, respectivamente, durante la primavera y el verano. No obstante, incluso esta localización presenta valores de indicadores biológicos que apuntan a una severa degradación en otoño e invierno. La diversidad de macroinvertebrados es particularmente baja en las muestras de verano y otoño con poblaciones dominadas por taxones que toleran la contaminación, como los Chironomidae. Los valores de abundancia son generalmente más elevados en primavera y más bajos en invierno. El porcentaje de Ephemeroptera y Trichoptera (EPT) es bajo, alcanzando un 31% entre ambos grupos. Los Plecoptera se encuentran completamente ausentes en todas las muestras. El porcentaje EPT y de Chironomidae están relacionados con la temperatura y la Demanda Bioquímica de Oxígeno (BOD). La calidad de este hábitat y la de sus sistemas biológicos ha mejorado en relación con anteriores estudios. El presente trabajo debe ayudar a identificar las medidas específicas necesarias para recuperar la calidad del hábitat y de su agua hasta condiciones de referencia
Microplastic Pollution in Portuguese Saltworks
Currently, microplastics are dispersed everywhere; from our oceans to our rivers, sediments, organisms, air, and even food resources. Therefore, this study aimed to assess the degree of contamination present in the Portuguese traditional table salts depending on their origin and type of salt. Fourteen samples were selected: seven from fleur de sel and seven from coarse salts, corresponding to seven distinct regions of the Portuguese territory. The concentration of microplastics, depending on salts’ origin, ranged between 595 and 5090 MPs/kg, in sea salt, and in Rio Maior’s well salt it varied from 3325 to 6430 MPs/kg. By salt type, the concentration of microplastics in the fleur de sel was 2320–6430 MPs/kg and in the coarse salt was 595–3985 MPs/kg. In the analyzed table salt, the most abundant anthropogenic particles were fibers (64%) and fragments (35%). The most predominant colors were transparent, blue, and black. The concentration of microplastics did not vary significantly (p > 0.05) between fleur de sel samples within different regions. However, statistically significant differences were found between coarse salt samples from the various regions. The results, gathered from this study, demonstrate the high contamination within artisanal Portuguese table salts, thus, becoming crucial to develop more future research, leading to a better understanding of the health risks associated with salt consumption
The courtship behaviour of the pipefish Nerophis lumbriciformis: Reflections of an adaptation to intertidal life
The courtship behaviour of Nerophis lumbriciformis
(Pisces: Syngnathidae) consists of three distinct
phases (initial courtship, spawning, and embrace)
marked by prominent behavioural changes. The first
courtship phase is characterised by female quivering.
Courtship activity increases from low to high levels of
quivering, causing undulatory head movements in the female.
In the second phase, the female transfers her eggs
onto the male incubating ventral surface. During the final
phase, the male wraps his body around the female
(embrace). Females actively initiate courtship indicating
that these pipefishes are courtship role reversed. The
complete lack of swimming and vertical movements in
the courtship behaviour of N. lumbriciformis, unlike in
the behaviour of other syngnathid species, suggests an
adaptation to intertidal conditions
Homing behaviour and individual identification of the pipefish Nerophis lumbriciformis (Pisces; Syngnathidae): A true intertidal resident?
Syngnathids have been the focus of growing interest due to their peculiar reproductive biology and vulnerability to
environmental degradation and overcollecting. In this study, near the south limit of the species’ geographic distribution,
a description of the homing behaviour of the worm pipefish, Nerophis lumbriciformis, based on the unique facial pigmentation
patterns, is presented. Even though the amount of facial pigmentation was substantially higher in larger adult females, suggesting
that it can be part of the secondary sexual repertoire of this sex role reversed species, this technique allowed for the positive
identification of adult individuals (males and females) during at least 19 months. Recaptures showed that this pipefish shows
a strong homing behaviour, with individuals being regularly captured within less than 2 m of the original identification event. The
absence of horizontal migrations to adjacent areas and the observation of adults in the subtidal, together with the overall low
number of recaptures (even though some individuals were cyclically resighted) highlighted the fact that the intertidal is not
N. lumbriciformis’ permanent residence. This observation also demonstrates that the estimation of the population size, important for
conservation purposes, based solely on intertidal data can be misleading because captured individuals are only a fraction of a larger,
mainly subtidal, population
Early life history of the pipe¢sh Nerophis lumbriciformis (Pisces: Syngnathidae)
The embryonic and larval development of the pipe¢sh Nerophis lumbriciformis is described. The full development
sequence lasted 30 d (at 14-15ºC), being shortened to 25-26 d at higher temperatures (16-17ºC),
and hatching occurred throughout a 2^3 d period. Unlike species of the genus Syngnathus, the newly
hatched larvae presented a functional mouth apparatus and the yolk sac completely absorbed
Temporal patterns of breeding and recruitment in Nerophis lumbriciformis (Pisces; Syngnathidae) related to seawater temperatures
The breeding season of Nerophis lumbriciformis, a cold water pipefish, was positively correlated
with seawater temperatures <15 5 C, whilst recruitment occurred at the end of the upwelling
season, when seawater temperature attained its maximum values. The observed alterations in
seawater temperatures, with steady year-round increases, and the consequent alteration of the
upwelling regime, may have dramatic consequences in the maintenance of N. lumbriciformis
populations, by reducing the breeding period and simultaneously contributing to the transport
of pelagic larvae northwards due to specific sea currents that occur outside the upwelling
season
Genetic structure and historical demography of the shanny Lipophrys pholis in the Portuguese coast based on mitochondrial DNA analysis
Inexistent
Activity rhythms and cyclical changes of microhabitat preferences in the intertidal pipefish Nerophis lumbriciformis (Pisces: Syngnathidae)
As an inhabitant of the intertidal zone, Nerophis
lumbriciformis predictably should show a clear
rhythmic activity, with its maximum closely correlated
with the high tide period, as observed in several other
rocky intertidal fish species. We investigated the rhythmic
activity patterns of N. lumbriciformis and analysed
to what extent specific substratum preferences may be
linked to water level and, ultimately, to the particular activity
rhythm patterns of the fish. To determine N. lumbriciformis
substratum preferences, two different experiments
were conducted. The first evaluated substratum
preferences from among a group of the four most common
substrates found in the sample area. The second experiment
evaluated the fish’s maintenance of that substratum
preference, after alteration of the water level in a
simulated ebb tide. From the available substrata, N. lumbriciformis
displayed a clear preference for algae until
the water level began to decrease. Then, the preference
radically shifted from algae to boulders. N. lumbriciformis
showed a clear rhythmic activity, affected by both
tidal and circadian periodicity, producing asymmetrical
activity peaks. Unlike the rhythms of other rocky intertidal
fish species, the maximum activity peaks were not
centred at the expected high tide period. The adaptive
explanation for the apparently peculiar activity peaks appears
to be related to the particular substratum preferences
of N. lumbriciformis. The detected circatidal period
seems, consequently, closely related to small migrations
between substrata, whilst the observed increase in diurnal
activity, independent of the tidal cycle, may be related to
predatory activity, since N. lumbriciformis is a visual
feeder
Ciclo anual de oogénesis en Lipophrys pholis (Pisces: Blenniidae)
Lipophrys pholis has been shown to be responsive to a variety of environmental contaminants, some of them able to impair reproduction. Description of the normal cycle of oogenesis of this newly proposed sentinel species is important since this data may function as a baseline for comparison in ecotoxicological studies, among other applications. Based on histological observations, L. pholis ovarian development in adult is asynchronous, and 7 ovarian germ cells can be described (oogonia, early and late perinuclear oocytes, cortical-alveolar oocytes, early vitellogenic oocytes, vitellogenic oocytes and spawning oocytes). Using a stereological approach together with the morphologic characteristics of ovarian cells, the ovarian cycle of L. pholis was divided into 3 maturation stages: early oogenesis (May); mid-oogenesis (September), and spawning (November to January). Ovarian cell proportions and gonadosomatic index confirmed that the reproductive period of L. pholis near the southern limit of distribution of the species occurs during cold-water periods, between November and May. The collected data will help to fill some of the gaps in information that still exist on L. pholis oogenesis, thus allowing a better integration of this species as a sentinel for the detection of contaminants in European coastal waters.En trabajos recientes, se ha visto que Lipophrys polis es sensible a diversos contaminantes medioambientales, algunos de los cuales pueden afectar a la reproducción. La descripción del ciclo normal de oogénesis de esta nueva propuesta de especie centinela es importante, ya que serviría como referencia para futuros estudios toxicológicos, entre otras aplicaciones. En base a observaciones histológicas, se pueden describir siete estados de los oocitos (oogonia, estado perinuclear temprano y tardío, estado cortico-alveolar, vitelogénesis temprana, vitelogénesis y oocitos desovados). Desde un enfoque estereológico, junto con las características morfológicas de las células ováricas, el ciclo ovárico de L. polis se ha dividido en tres estados de maduración: oogénesis temprana (mayo), oogénesis media (septiembre) y desove (de noviembre a enero). Las proporciones de las células ováricas y el índice gonadosomático, confirmaron que el periodo reproductivo de L. polis, en el límite meridional de distribución de la especie, se produce durante los periodos de agua fría, entre noviembre y mayo. Los datos obtenidos ayudarán a cubrir algunas de las lagunas que todavía existen en el conocimiento de la ovogénesis de L. pholis, permitiendo, por tanto, una mejor integración de esta especie como centinela para la detección de contaminantes en las aguas costeras europeas
Desenho na pesquisa com crianças: análise na perspectiva histórico-cultural
This article discusses the use of drawing to complement interviews when doing research with children. It is based on a research project that investigated the attributed to work by children of 7 to 8 years of age by using drawing as a resource. In a historical-cultural perspective in psychology, the drawing of a child is understood as a form of language in which the human being creative imagination is expressed. To analyze the results in line with this approach, it is important to consider not only the process of drawing, but also the conditions in which it takes place – which necessarily includes the relationship between the researcher and the research participant – as well as the end product. Drawings express meanings that are socially shared, but the meanings the authors/children ascribe to their drawings can only be understood in the light of their own explanation. Through their on the drawings one can get important information on the historical and cultural environment where they live and how they signify it. Key words: children’s drawings, research, historical-cultural perspective.Neste artigo discute-se o uso do desenho como procedimento complementar à entrevista em pesquisas com crianças. Esta discussão foi baseada em uma pesquisa que investigou os sentidos do trabalho atribuídos por crianças de 7 a 8 anos de idade, com a utilização do desenho como recurso. O desenho infantil é compreendido, à luz da perspectiva histórico-cultural em psicologia, como forma de linguagem na qual se expressa e constitui a imaginação criadora do ser humano. Para a análise dos resultados, sob esse enfoque, é importante considerar tanto o processo de desenhar, as condições de sua produção – que necessariamente requerem o olhar para as relações entre pesquisador e sujeito da pesquisa – quanto o produto final. Isto porque o desenho expressa significados compartilhados socialmente, porém os sentidos que o autor/criança atribui ao desenho produzido somente podem ser compreendidos com as explicações da criança sobre o que produziu. Por meio da verbalização sobre o desenho é que se podem obter informações significativas sobre o contexto histórico-cultural em que a criança vive e como o significa. Palavras-chave: desenho infantil, pesquisa, perspectiva histórico-cultural