34 research outputs found
Fish-based groups for ecological assessment in rivers: the importance of environmental drivers on taxonomic and functional traits of fish Assemblages
The use of river-types is of practical value, serving as groups for which
assessment procedures can be developed and applied. An abiotic typology
was set by the Portuguese Water Agency, mainly based on 6 major
morphoclimatic regions. However, to be biologically meaningful, this typology
should fit the distribution patterns of the biological quality elements
communities proposed in Water Framework Directive under the lowest
possible human pressure. This study aimed to identify and characterize
fish-based geographical groups for continental Portugal and their environmental
and geographical discriptors, using taxonomic and functional
traits. Sampling took place between 2004 and 2006 during Spring. Fish
fauna from 155 reference sites was analysed using a multivariate
approach. Cluster Analysis on fish composition identified 10 fish-groups,
expressing a clear correspondence to the river basin level, due to the
restrict basin distribution of many species. Groups showed a wider aggregation
in 4 regions with a larger geographical correspondence, statistically
supported by Similarity Analysis, both on fish composition and mostly on
fish metrics/guilds. Principal Components Analysis revealed major environmental
drivers associated to fish-groups and fish-regions. Fish-groups
were hierarchically grouped over major and local regions, expressing a
large-scale response to a North-South environmental gradient defined by
temperature, precipitation, mineralization and altitude, and a regional scale
response mainly to drainage area and flow discharge. From North to
South, fish-regions were related to the morphoclimatic regions. Results
contributed to reduce redundance in abiotic river-types and set the final
typology for Portuguese rivers, constituting a fundamental tool for planning
and managing water resources
Best Pratice Guide to Manage Vegetation and Promote Biodiversity in Linear Infrastructures
The present guide is based on the experience acquired in the framework of the LIFE LINES project (LIFE14 NAT/PT/001081) and intends to compile and disseminate the recommendable procedures for the management of biodiversity, particularly of plant diversity, in the marginal areas of linear infrastructures, primarily focusing on the national roads, decommissioned railways now used for recreation purposes (ecotrails) and power lines of very high voltage. The guide includes technical information for those in charge of the management of roads, trails and power lines (concession holders, municipalities), for environmental consultancy (Agência Portuguesa do Ambiente, Instituto de Conservação da Natureza e Florestas), and for landscape and agroforestry technicians, as well as for the general public
Guião de Boas Práticas de Gestão da Vegetação para a Promoção e Biodiversidade em Infraestruturas Lineares
O presente guião de boas práticas tem por base a experiência
adquirida ao longo do projeto LIFE LINES (LIFE14 NAT/PT/001081),
pretendendo reunir e divulgar procedimentos recomendáveis para a
gestão da biodiversidade, com ênfase na diversidade vegetal das zo nas marginais associadas às infraestruturas lineares, e focando-se, so bretudo, em estradas nacionais, ferrovias desativadas com uso recrea tivo (ecopistas) e linhas elétricas de muito alta tensão.
O guião inclui informação técnica dirigida às entidades gestoras de
estradas, caminhos pedestres e de linhas de muito alta tensão (con cessionárias, autarquias), a responsáveis pela Avaliação de Impacte
Ambiental de infraestruturas lineares (Agência Portuguesa do Ambien te, Instituto de Conservação da Natureza e Florestas), a técnicos da
área do paisagismo e operações agroflorestais, bem como informação
dirigida ao público em geral
The european water framework directive facing current challenges: recommendations for a more efficient biological assessment of inland surface waters
High quality water is vital for human life, and ensuring its availability is a basic requirement and a
major societal aim. The Water Framework Directive (WFD; 2000/60/EC) is a key piece of legislation
for the protection and sustainable use of water in the European Union. In this work we briefly review
the WFD directive and the current status of European inland surface waters. Additionally, we
summarize major challenges and threats for the biological assessment of inland surface waters
under climate change effects and invasion by alien species, and highlight the emerging tools
and approaches that might help improve biological assessments, including molecular indices
based on environmental DNA (eDNA), to new data from the Earth Observation programmes, and
data-sharing platforms. Finally, we present recommendations to improve monitoring systems
and assessments in the context of the WFD. Developments in this field may increase the
likelihood of assuring high quality water for societyFRESHING Project funded by the Portuguese Foundation for Science
and Technology (FCT) and COMPETE (PTDC/AAG-MAA/
2261/2014 – POCI-01-0145-FEDER-356 016824). AFF,
AGR, and JPR were supported by FRESHING. FMSM was
supported by FCT grant SFRH/BD/104703/2014. MJF was
supported by the strategic project UID/MAR/04292/2013
granted to MAR
Patterns of habitat use of the endangered fish species Saramugo, Anaecypris hispanica, and the invasive Bleak, Alburnus alburnus: implications for native fish fauna conservation.
The Bleak (Alburnus alburnus) is an invasive fish occurring in high density in many streams and rivers of the Iberian Peninsula, namely in the Guadiana basin. Considering its invasive success, the coexistence with native species can led to negative impacts. Although this species has been considering a biological threat, there is still a lack of knowledge on many aspects of its bio-ecology in Mediterranean climate streams. This study was developed under the Life Project for the Conservation of Saramugo (Anaecypris hispanica) in the Guadiana River Basin and aimed to evaluate the potential impact of the Bleak on the Saramugo populations, considering the patterns of habitat use and distribution. Data were collected in the Guadiana river basin during the spring of 2015 and 2016. The patterns of habitat use, habitat preferences and overlap were quantified. The spatio-temporal variability of the Bleak captures was also evaluated. Saramugo exhibited habitat preferences for deep pools, medium/deep runs and fast riffles and the Bleak showed preference for medium /deep pools and medium/deep runs, resulting in a high habitat overlap between both species. Substrate type and vegetation elements were important for both species, though with distinct preferences. The Bleak performed seasonal movements in the river network that seems related to a dispersal strategy to assure the occupation of new stream areas. The obtained results contribute to support decision-making on the implementation of effective measures that selectively benefit the native fish fauna conservation
Dedifferentiated liposarcoma with leukocytosis. A case report of G-CSF-producing soft-tissue tumors, possible association with undifferentiated liposarcoma lineage
<p>Abstract</p> <p>Background</p> <p>Granulocyte-colony-stimulating factor (G-CSF) functions as a hematopoietic growth factor and it is responsible for leukocytosis. G-CSF-producing tumors associated with leukocytosis include various types of malignancies.</p> <p>Case presentation</p> <p>We report the case of a 72-year-old man with dedifferentiated liposarcoma characterized by dedifferentiated components of malignant fibrous histiocytoma (MFH)-like features in addition to well-differentiated lipoma-like liposarcoma, arising from his upper arm. Preoperative laboratory data showed leukocytosis (103,700/μl). The serum level of G-CSF was also elevated (620 pg/ml [normal, <8 pg/ml]). Nine days after the surgery, the leukocytosis was relieved (WBC; 6,920/μl) and the elevated serum G-CSF level was significantly decreased (G-CSF; 12 pg/ml). One month after the surgery, leukocytosis gradually began to appear again. Three months after the surgery metastatic lung lesions were confirmed, and the patient subsequently died of respiratory problems. In the English literature regarding soft-tissue tumors with leukocytosis, including the current case, we could review a total of 6 cases of liposarcoma with leukocytosis. The subtype of these 6 liposarcoma cases was undifferentiated liposarcoma, comprising dedifferentiated liposarcoma in 4 cases and pleomorphic liposarcoma in 2 cases.</p> <p>Conclusion</p> <p>Since the only other soft-tissue tumor that was associated with leukocytosis was MFH, and since MFH is characterized by the absence of any specific differentiation, we would like to propose a possible association between G-CSF-producing soft-tissue tumors and an undifferentiated liposarcoma lineage, such as dedifferentiated liposarcoma or pleomorphic liposarcoma.</p
Random forests to evaluate interspecific interactions in fish distribution models
[EN] Previous research indicated that high predictive performance in species distribution modelling can be obtained by combining both biotic and abiotic habitat variables. However, models developed for fish often only address physical habitat characteristics, thus omitting potentially important biotic factors. Therefore, we assessed the impact of biotic variables on fish habitat preferences in four selected stretches of the upper Cabriel River (E Spain). The occurrence of Squalius pyrenaicus and Luciobarbus guiraonis was
related to environmental variables describing biotic interactions (inferred by relationships among fish abundances) and channel hydro-morphological characteristics. Random Forests (RF) models were trained and then validated using independent datasets. To build RF models, the conditional variable importance was used together with the model improvement ratio technique. The procedure showed effectiveness in identifying a parsimonious set of not correlated variables, which minimize noise and improve model performance in both training and validation phases. Water depth, channel width, fine
substrate and water-surface gradient were selected as most important habitat variables for both fish. Results showed clear habitat overlapping between fish species and suggest that competition is not a strong factor in the study area.This research has been developed in the framework of the HolRiverMed project (FP7-PEOPLE-2010-275577, Marie Curie Actions, Intra-European Fellowships) and the SCARCE project (Assessing and predicting effects on water quantity and quality in Iberian rivers caused by global change, Consolider-Ingenio 2010 CSD2009-00065). Data collection was partially funded by the Spanish Ministry of Environment, Rural and Marine Affairs, the Jucar River Basin District Authority and the Spanish Ministry of Education and Science (POTECOL, CGL2007-66412). We thank Juan Diego Alacaraz-Hernandez, Matias Peredo-Parada and Aina Hernandez-Mascarell for their help with field work and suggestions on data analysis.Vezza, P.; Muñoz Mas, R.; Martinez-Capel, F.; Mouton, A. (2015). Random forests to evaluate interspecific interactions in fish distribution models. Environmental Modelling and Software. 67:173-183. https://doi.org/10.1016/j.envsoft.2015.01.005S1731836
Effects of natural hydrological variability on fish assemblages in small Mediterranean streams : implications for ecological assessment
Small Mediterranean streams are shaped by predictable seasonal events of flooding and drying over an annual cycle, and present a strong inter and intra-annual variation in flow regime. Native fish assemblages in these streams are adapted to this natural environmental variability. The distinction of human-induced disturbances from the natural ones is thus a crucial step before assessing the ecological status of these streams. In this aim, the present study evaluates the effects of natural hydrological variability on fish assemblages from disturbed and least disturbed sites in small intermittent streams of south Portugal. Data were collected over the last two decades (1996-2011) in 14 sites located in the Guadiana and Sado river basins. High variability of fish assemblages was strongly dependent on human-induced disturbances, particularly nutrient/organic load and sediment load, and on natural hydrological variability. Natural hydrological variability can act jointly with anthropogenic disturbances, producing changes on fish assemblages structure of small intermittent streams. In least disturbed sites, despite the natural disturbances caused by inter-annual rainfall variations (including drought and flood events), fish assemblages maintained a long-term stability and revealed a high resilience. On the contrary, disturbed sites presented significantly higher variability on fish assemblages and a short and long-term instability, reflecting a decrease on the resistance and resilience of fish assemblages. Under these conditions, fish fauna integrity is particularly vulnerable and the ecological assessment may be influenced by natural hydrological variations. High hydrological variability (especially if it entails high frequency of dryer years and meaningful cumulative water deficit) may affect the impact of the human pressures with significant and consistent consequences on fish assemblage composition and integrity. In this study, fish metrics that maximize the detection of human degradation and minimize the response to natural variability were based on the relative abundance of native species (insectivorous species, eurytopic species, water column species, native lithophilic species), relative abundance of species with intermediate tolerance and relative number of exotic species. Results highlight the importance of assessing temporal variability on stream biomonitoring programs and emphasize the need to improve the assessment tools, accounting for long-term changes in fish assemblages, namely by selecting the most appropriate fish metrics that respond to anthropogenic disturbances but exhibit low natural temporal variability, essential both in the characterization of the biological reference conditions and in the development of fish indexes in intermittent streams
Evaluation of potential hybridization between native fishes and the invasive bleak, Alburnus alburnus (Actinopterygii: Cypriniformes: Cyprinidae)
Background. Freshwater fishes are among the most threatened taxa worldwide. The proliferation of introduced species in the Iberian Peninsula is currently one of the main drivers of native fish declines. One of such species, the bleak, Alburnus alburnus (Linnaeus, 1758), has become widespread in the last 25 years and, due to its phylogenetic proximity, poses a high risk of hybridization with native species. The aim of this study was to improve the current knowledge on this issue by 1) evaluating the presence of hybrids with Alburnus alburnus in the wild, using molecular screening of individuals representing the intermediate morphology and 2) testing if artificial crosses between Alburnus alburnus and the highly threatened native cyprinid Anaecypris hispanica (Steindachner, 1866) resulted in viable hybrid offspring. Materials and methods. The genetic profile of Alburnus alburnus was established using the cytochrome b and beta-actin genes to allow comparisons with the profiles of the sympatric species with which it could potentially hybridize: Anaecypris hispanica; Squalius alburnoides (Steindachner, 1866); and Squalius pyrenaicus (Günther, 1868). This profile was further used to assess if fish with the intermediate morphological features were indeed hybrids. Finally, artificial crosses between Alburnus alburnus and Anaecypris hispanica were conducted to test the viability of the offspring. Results. Alburnus alburnus individuals were genetically identical to the stocks introduced in Spain and the Czech Republic. A reference library composed of 15 species-specific nDNA loci was built and used to characterize wild fish showing intermediate morphological features. Results showed that Alburnus alburnus is currently hybridizing with males and females of Squalius alburnoides and that morphometric identification is insufficient for a reliable detection of the hybrids. Artificial crosses between the bleak and the highly threatened Anaecypris hispanica did not result in viable offspring. Conclusion. Phylogenetic relatedness, traduced in the absence of pre- and post-zygotic barriers to reproduction, together with other factors related to the ecology and life history of the species involved are essential for hybridization to occur. As such, the proliferation of the bleak through the Iberian hydrographical network represents a serious additional threat for the already imperilled native Squalius and Anaecypris species
Evaluation of potential hybridazion between native fish and invasive bleak Alburnus alburnus
Background. Freshwater fishes are among the most threatened taxa worldwide. The proliferation of introduced species in the Iberian Peninsula is currently one of the main drivers of native fish declines. One of such species, the bleak, Alburnus alburnus (Linnaeus, 1758), has become widespread in the last 25 years and, due to its phylogenetic proximity, poses a high risk of hybridization with native species. The aim of this study was to improve the current knowledge on this issue by 1) evaluating the presence of hybrids with Alburnus alburnus in the wild, using molecular screening of individuals representing the intermediate morphology and 2) testing if artificial crosses between Alburnus alburnus and the highly threatened native cyprinid Anaecypris hispanica (Steindachner, 1866) resulted in viable hybrid offspring.
Material and methods. The genetic profile of Alburnus alburnus was established using the cytochrome b and beta-actin genes to allow comparisons with the profiles of the sympatric species with which it could potentially hybridize: Anaecypris hispanica; Squalius alburnoides (Steindachner, 1866); and Squalius pyrenaicus (Günther, 1868). This profile was further used to assess if fish with the intermediate morphological features were indeed hybrids. Finally, artificial crosses between Alburnus alburnus and Anaecypris hispanica were conducted to test the viability of the offspring.
Results. Alburnus alburnus individuals were genetically identical to the stocks introduced in Spain and the Czech Republic. A reference library composed of 15 species-specific nDNA loci was built and used to characterize wild fish showing intermediate morphological features. Results showed that Alburnus alburnus is currently hybridizing with males and females of Squalius alburnoides and that morphometric identification is insufficient for a reliable detection of the hybrids. Artificial crosses between the bleak and the highly threatened Anaecypris hispanica did not result in viable offspring.
Conclusion. Phylogenetic relatedness, traduced in the absence of pre- and post-zygotic barriers to reproduction, together with other factors related to the ecology and life history of the species involved are essential for hybridization to occur. As such, the proliferation of the bleak through the Iberian hydrographical network represents a serious additional threat for the already imperilled native Squalius and Anaecypris species.
Keywords: hybridization risk, invasive fish species, biodiversity loss, conservationEuropean Union LIFE program (LIFE13/ NAT/PT/000786-Saramugo); the Fundação para a Ciência e Tecnologia (FCT) of Portugal, through the strategic project UID/MAR/04292/2013 granted to MARE