Palatability of the Asian clam Corbicula fluminea (Müller 1774) in an invaded system

Biotic interactions such as predation may influence the success of invasive alien species (IAS). Although the Asian clam Corbicula fluminea is recognized as one of the most problematic aquatic IAS, few studies have investigated its use as a food resource. In this study, we aimed to investigate (i) the palatability of C. fluminea under natural (Minho River) and laboratory conditions and (ii) if C. fluminea submitted to different conditions (individuals from Lima and Minho Rivers) vary in palatability. Soft tissues from different Corbicula populations, plus soft tissues from a native clam, tuna and Corbicula shell powder were offered to consumers. Field assays were performed seasonally and laboratory assays only in summer; both assays also tested possible differences during distinct periods of the day. Overall, in natural conditions, the treatments containing C. fluminea had a low palatability. In laboratory assays, higher consumption (almost two times) was observed for Cyprinus carpio and Anguilla anguilla. Also, C. fluminea palatability was different between populations, with the treatment Corbicula Lima being more consumed than Corbicula Minho. Despite the low values of consumption in the field, laboratory results suggest that C. fluminea soft tissues can be a food resource to some species.This study was conducted as part of the project FRESCHO: Multiple implications of invasive species on Freshwater Mussel coextinction processes, supported by FCT (contract: PTDC/AGRFOR/1627/2014). MI is supported by a Post-doc grant (SFRH/BPD/90088/2012) from the Portuguese Foundation for Science and Technology—FCT through POPH/FSE funds. RS also acknowledge the support of the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER007569) funded by national funds through the FCT I.P and by the ERDF through the COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI)

Differences in the macrozoobenthic fauna colonising empty bivalve shells before and after invasion by Corbicula fluminea

Bivalve shells can potentially alter the structure of aquatic benthic communities. However, little is known about the effect that different shell morphologies have on their associated fauna. This study aimed to understand how empty shells, from four different freshwater bivalve species, affect macrozoobenthic communities, using the River Minho (Iberian Peninsula) as a study area. Three native (Anodonta anatina, Potomida littoralis, Unio delphinus) and one non-indigenous (Corbicula fluminea) species were used for this research. Comparisons among species and between scenarios (i.e. before and after invasion by C. fluminea) were performed. Our results suggest that macrozoobenthic community structure did not vary among treatments, with the exception of species richness, which was higher on shells of native species. Furthermore, little difference was detected when comparing scenarios with and without C. fluminea shells, despite dissimilarities in size and morphology between species. The empty shells of C. fluminea partially (in terms of density and biomass, but not in species richness) replaced the role of empty shells of native species as a physical substratum for the associated macrozoobenthic community.Martina Ilarri is supported by a Post-doc grant (SFRH/BPD/90088/2012) from the Portuguese Foundation for Science and Technology – FCT through POPH/FSE funds. This study was conducted within the scope of the project ECO-IAS: Ecosystem-level impacts of an invasive alien species, supported by FCT and COMPETE funds (contract: PTDC/AAC-AMB/116685/2010) and was also partially supported by the European Regional Development Fund (ERDF) through COMPETE funds (PEst-C/MAR/LA0015/2011) and by FCT/MEC through Portuguese funds (PIDDAC – PEst-OE/BIA/UI4050/2014).info:eu-repo/semantics/publishedVersio

Contrasting decay rates of freshwater bivalves’ shells: aquatic versus terrestrial habitats

Freshwater flow regimes are particularly vulnerable to global climate change with changes to the volume and regime of water contributing to global declines in freshwater biodiversity. Droughts or floods can cause massive mortalities of freshwater bivalves, facilitating the accumulation of shells in the aquatic but also in adjacent terrestrial habitats. In order to fully understand the long term impact of these massive mortality events, it is important to assess how bivalve shells persist in the environment. Given that, the present study aimed at studying the shell decays of four different bivalve species (Anodonta anatina, Corbicula fluminea, Potomida littoralis and Unio delphinus) in aquatic (i.e. river) versus terrestrial (i.e. sand soil) habitats. Shell decay rates were significantly different among species and habitats. In the aquatic habitat the shell decay rates varied among species, with the native species A. anatina, which have the largest and thinnest shell, showing the highest decay rate. Alternatively, in the terrestrial habitatthe shell decay rates were more even among species and not related to a particular shell feature or morphology, with the native U. delphinus showing the fastest decay. The shell decay rates were 6 to 12 times higher in aquatic than in the terrestrial habitat. These results suggest that bivalve shells can persist for long periods of time on both habitats (but mainly in terrestrial), which may perhaps trigger significant changes on the ecosystem structure and functioning.This study was conducted in the scope of the project ECO-IAS: Ecosystem-level impacts of an invasive alien species, supported by FCT and COMPETE funds (contract: PTDC/AAC-AMB/116685/2010) and was also partially supported by the European Regional Development Fund (ERDF) through COMPETE funds (PEst-C/ MAR/LA0015/2011) and by FCT/MEC through Portuguese funds (PIDDAC - PEst-OE/BIA/UI4050/2014). Martina Ilarri is supported by a Post-doc grant from the FCT (SFRH/BPD/90088/2012).info:eu-repo/semantics/publishedVersio

Biodiversity associated to floating wetland islands

Floating wetland islands (FWI) are nature-based solutions that can be applied in different water bodies, such lakes, ponds and rivers, considering a wide range of purposes. They have been considered for eutrophication abatement, wastewater treatment and ecosystem rehabilitation. They are of great value since their efficiency relies on bioremediation processes and are thus very versatile in terms of water depuration but also on biodiversity promotion. These systems comprise a floating platform, selected plants and an anchoring system. Depending on their configuration, they will attract and harbor different organisms such macrofauna and microorganisms, that will use the platform as shelter, habitat, stepping stone, nursery, food source among other benefits. The plant species are of particular interest since they are the living interface between the platform and the water body and they must be selected according to criteria that will enable their successful establishment having in consideration the biotic factors. The present paper intends to give an overview of the role of FWI towards their associated biodiversity and what has been identified in literature as the main groups that can be found and related to operational conditions. This approach can support future decisions concerning the FWI implementation conditions and components towards biodiversity enhancement.info:eu-repo/semantics/acceptedVersio

Effects of Glyphosate on the Environment and Human Health

Glyphosate is a herbicide of a wide spectrum that alters the production of amino acids in plants, leading to their death. Due to its properties, it is used to eliminate weeds that interfere with human activity. The intensive use of this herbicide in the past decades has led to its frequent encounter in the environment as it has been detected in water, animals, and food destined for human consumption. Its impact on human health and the rest of living organisms has not been fully explored, given that many authors enter into contradictions with one another, specifically surrounding the role of surfactants in the commercial presentation of herbicides. The use of pesticides can have significant impacts on ecosystems, threatening bio-cultural diversity due to genetic contamination from transgenic crops. The effectiveness of Glyphosate-based herbicides in weed control is diminishing due to weed tolerance. However, the use of herbicides remains prevalent in large-scale crops due to the challenges of organic food production. In addition, the probable conflict of interest by the agrochemical industry does not bring a full picture with respect to the actions that world governments should take. Banning GLP-based herbicides may lead to the use of other pesticides, in which the long-term impacts will require further studies. The motivation for this research is the review of the latest advances of glyphosate in the world, considering the use and prohibitions of this herbicide, its interaction with water and soil, as well as the effects on both the environment and health. The search for information for this paper was carried out in the Mendeley, Elsevier, and Springer databases by filtering by the suitable keywords

Effects of tourist visitation and supplementary feeding on fish assemblage composition on a tropical reef in the Southwestern Atlantic

The effects of tourist visitation and food provisioning on fish assemblages were assessed by visual censuses (stationary technique) carried out in a tropical reef in Northeastern Brazil. Comparisons of species abundance, richness, equitability, and trophic structure in the presence (PT) and absence (AT) of tourists suggest that tourist visitation and supplementary food influenced the structure of the fish assemblage, as follows: (a) diversity, equitability and species richness were significantly higher on the AT period, while the abundance of a particular species was significantly higher during PT; (b) trophic structure differed between the AT and PT periods, omnivores being more abundant during the latter period, while mobile invertivores, piscivores, roving herbivores and territorial herbivores were significantly more abundant on AT. Reef tourism is increasingly being regarded as an alternative to generate income for human coastal communities in the tropics. Therefore, closer examination of the consequences of the various components of this activity to reef system is a necessary step to assist conservation and management initiatives

Massive mortality of the Asian clam Corbicula fluminea in a highly invaded area

MI is supported by a PhD. grant from Portuguese Foundation for Science and Technology-FCT (SFRH/BD/33387/2008). Special thanks to Eduardo Martins for technical assistance and Jonathan Wilson for helpful English revision

SNEE: a query processor for wireless sensor networks

A wireless sensor network (WSN) can be construed as an intelligent, large-scale device for observing and measuring properties of the physical world. In recent years, the database research community has championed the view that if we construe a WSN as a database (i.e., if a significant aspect of its intelligent behavior is that it can execute declaratively-expressed queries), then one can achieve a significant reduction in the cost of engineering the software that implements a data collection program for the WSN while still achieving, through query optimization, very favorable cost:benefit ratios. This paper describes a query processing framework for WSNs that meets many desiderata associated with the view of WSN as databases. The framework is presented in the form of compiler/optimizer, called SNEE, for a continuous declarative query language over sensed data streams, called SNEEql. SNEEql can be shown to meet the expressiveness requirements of a large class of applications. SNEE can be shown to generate effective and efficient query evaluation plans. More specifically, the paper describes the following contributions: (1) a user-level syntax and physical algebra for SNEEql, an expressive continuous query language over WSNs; (2) example concrete algorithms for physical algebraic operators defined in such a way that the task of deriving memory, time and energy analytical cost-estimation models (CEMs) for them becomes straightforward by reduction to a structural traversal of the pseudocode; (3) CEMs for the concrete algorithms alluded to; (4) an architecture for the optimization of SNEEql queries, called SNEE, building on well-established distributed query processing components where possible, but making enhancements or refinements where necessary to accommodate the WSN context; (5) algorithms that instantiate the components in the SNEE architecture, thereby supporting integrated query planning that includes routing, placement and timing; and (6) an empirical performance evaluation of the resulting framework