Foraminiferal biotopes and their distribution control in Ria de Aveiro (Portugal): a multiproxy approach

Ria de Aveiro, which is located in the centre of Portugal (40° 38′ N, 8° 45′ W), is a well-mixed and complex coastal lagoon that is separated from the sea by a sandy barrier and connects with the Atlantic through an artificial inlet. Tidal currents are the main factor controlling the lagoon’s hydrodynamics and, to a great extent, the sedimentary dynamic. The inner lagoonal zones receive input from several rivers and experience the pressure caused by the accumulation of organic matter and pollutants (namely, trace metals) from diverse anthropic activities. This paper is the first piece of work aiming to recognize, characterize and explain the main benthic foraminiferal biotopes in Ria de Aveiro. To provide a broad overview of this kind of setting, our results are compared to those of previous published studies conducted in similar transitional environments. The research is based on an investigation of 225 sites spread throughout this ecosystem. Utilizing a statistical approach, this study analyses the details of dead benthic foraminiferal assemblages composed of 260 taxa, the texture and composition (mineralogical and geochemical) of the sediment and physicochemical data. On the basis of the results of R-mode and Q-mode cluster analyses, several different biotopes can be defined as marsh biotope/near-marsh biotope; marginal urban/marginal urban mixing biotope; inner-outer lagoon biotope or enclosed lagoon; outer lagoon biotope, mixed sub-biotope; and outer lagoon, marine sub-biotope. These biotopes are related to foraminifera assemblages and substrate type and are influenced by local currents, water depth, chemical and physicochemical conditions, river or oceanic proximity, and anthropogenic impact, as evidenced by the mapping of the six factor loadings of the principal component analysis conducted herein. Based on a similar methodology of analysis as that applied in previous studies in the Lagoon of Venice, comparable biotypes were identified in Lagoon of Aveiro.     

Gastroenteric Viruses Detection in a Drinking Water Distribution-to-Consumption System in a Low-Income Community in Rio de Janeiro

Food and Environmental Virology - The availability of drinking water is one of the main determinants of quality of life, disease prevention and the promotion of health. Viruses are important agents...     

Trace elements: water-sediment interactions in tropical rivers

Environmental Science and Pollution Research - This research aimed to determine the water-sediment interaction (partition coefficient Kd) of trace element (Cd, Cu, total Cr, Pb, and Zn) in tropical...     

Assessment of aquatic plants in the reservoirs of AES-tietê and development of an integrated control model for the most important species

The general objective of this work was to develop a monitoring and management model for aquatic plants that could be used in reservoir cascades in Brazil, using the reservoirs of AES-Tietê as a study case. The investigations were carried out at the reservoirs of Barra-Bonita, Bariri, Ibitinga, Promiss?o, and Nova-Avanhandava, located in the Tietê River Basin; Agua Vermelha, located in the Grande River Basin; Caconde, Limoeiro, and Euclides da Cunha, which are part of the Pardo River Basin; and the Mogi-Gua?u reservoir, which belongs to the Mogi-Gua?u River basin. The main products of this work were: development of techniques using satellite-generated images for monitoring and planning aquatic plant control; planning and construction of a boat to move coating plant masses and an airboat equipped with a DGPS navigation and application flow control system. Results allowed to conclude that the occurrence of all types of aquatic plants is directly associated with sedimentation process and, consequently, with nutrient and light availability. Reservoirs placed at the beginning of cascades are more subject to sedimentation and occurrence of marginal, floating and emerged plants, and are the priority when it comes to controlling these plants, since they provide a supply of weeds for the other reservoirs. Reservoirs placed downstream show smaller amounts of water-suspended solids, with greater transmission of light and occurrence of submerged plants.     

Disaster mitigation and preparedness on the Nicaraguan post-Mitch agenda

Nicaragua provides an example of how a major disaster, in this case Hurricane Mitch, can transform the national agenda for disaster mitigation and preparedness. Hurricane Mitch was a reminder of how extremely disaster prone Nicaragua is, and also how neoliberal reforms have weakened governmental response capacity. In the face of critiques of how governmental policies had affected preparedness and response, discussions of this transformation became a highly politicised process where the debate over alternative development models tended to overshadow the original calls to strengthen risk management. Progress can be seen in some areas, such as disaster mitigation through environmental management. This study of NGO roles, and their relations with other key actors, draws attention to the need to anchor improved risk management in local-level NGO-government collaboration. Structures are being put into place to achieve this aim, but dependence on donor financing raises questions regarding the longer-term sustainability of these efforts.     

Antiviral Activity of Ctn[15-34], A Cathelicidin-Derived Eicosapeptide,Against Infectious Myonecrosis Virus in <Emphasis Type="Italic">Litopenaeus vannamei</Emphasis> Primary Hemocyte Cultures

The shrimp farming has been converted into a mature aquaculture industry dealing with over millions of metric tonnes of processed commodities. Nevertheless, the global shrimp productions are constantly threatened by disease outbreaks, mainly triggered by rapidly disseminating viruses. Infectious myonecrosis virus (IMNV) is one of these epizootic agents affecting shrimp production in Brazil, of which no treatment exists. Herein, the antiviral activity against IMNV of an eicosapeptide, named Ctn[15-34], derived from a member of the cathelicidin family of antimicrobial peptides, was demonstrated. Cultures of hemocytes from Litopenaeus vannamei were established that support IMNV replication and infectivity titration. The cytotoxic effect of IMNV in culture and the in vitro anti-IMNV activity of Ctn[15-34] were assessed using a high-sensitive fluorescent-based method in combination with quantitative PCR. The Ctn[15-34] (<12.5 µM) neutralized the toxic effects of IMNV at loads sufficient to kill 50% of shrimp hemocytes. This study reported for the first time the replication of IMNV in vitro and the employment of a straightforward methodology to assess cell viability and viral/antiviral activities. In addition, it provided the basis for the development of the anti-infective multi-effector Ctn[15-34] eicosapeptide and analogs as components of antiviral formulations against shrimp viral diseases.     

Environmental photochemical fate of pesticides ametryn and imidacloprid in surface water (Paranapanema River,São Paulo,Brazil)

In addition to direct photolysis studies, in this work the second-order reaction rate constants of pesticides imidacloprid (IMD) and ametryn (AMT) with hydroxyl radicals (HO^●), singlet oxygen (¹O₂), and triplet excited states of chromophoric dissolved organic matter (³CDOM^*) were determined by kinetic competition under sunlight. IMD and AMT exhibited low photolysis quantum yields: (1.23?±?0.07)?×?10^–2 and (7.99?±?1.61)?×?10^–3 mol Einstein^?1, respectively. In contrast, reactions with HO^● radicals and ³CDOM* dominate their degradation, with ¹O₂ exhibiting rates three to five orders of magnitude lower. The values of k_IMD,HO● and k_AMT,HO● were (3.51?±?0.06)?×?10⁹ and (4.97?±?0.37)?×?10⁹ L mol^?1 s^?1, respectively, while different rate constants were obtained using anthraquinone-2-sulfonate (AQ2S) or 4-carboxybenzophenone (CBBP) as CDOM proxies. For IMD this difference was significant, with k_IMD,3AQ2S*?=?(1.02?±?0.08)?×?10⁹ L mol^?1 s^?1 and k_IMD,3CBBP*?=?(3.17?±?0.14)?×?10⁸ L mol^?1 s^?1; on the contrary, the values found for AMT are close, k_AMT,3AQ2S*?=?(8.13?±?0.35)?×?10⁸ L mol^?1 s^?1 and k_AMT,3CBBP*?=?(7.75?±?0.80)?×?10⁸ L mol^?1 s^?1. Based on these results, mathematical simulations performed with the APEX model for typical levels of water constituents (NO₃^?, NO₂^?, CO₃^2?, TOC, pH) indicate that the half-lives of these pesticides should vary between 24.1 and 18.8 days in the waters of the Paranapanema River (São Paulo, Brazil), which can therefore be impacted by intensive agricultural activity in the region.

     

Electrochemical degradation of amoxicillin in acidic aqueous medium using TiO2-based electrodes modified by oxides of transition metals

Environmental Science and Pollution Research - One of the most widely used antibiotics is amoxicillin (AMX), which is the most widely used in humans and animals, but it is discharged metabolically...     

Degradation features of pesticides: a review on (metallo)porphyrin-mediated catalytic processes

Environmental Science and Pollution Research - Pesticides have been used to kill pests such as insects, fungi, rodents, and unwanted plants. Since these compounds are potentially toxic to the...