Browsing by Author "Sousa, Antonio"
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- Climate and safety behaviors: The case of solitary work in water supply and wastewater treatment systemsPublication . Sousa, Antonio; Sousa, Cátia; Goncalves, Gabriela; Zica, Jose; Arezas, P; Baptista, JS; Carneiro, P; Cordeiro, P; Costa, N; Melo, R; Miguel, AS; Perestrelo, GOccupational safety research has made it possible to observe the safety climate as an organizational valence associated with workers' safety behaviors. Considering that the safety climate concerns the workers' shared perception of the safety culture of the organization, it was in the interest of this study to assess to what extent the safety climate and the safety behaviors of workers is affected by their level of isolation. For this purpose, a case study was developed with workers from the water supply and wastewater treatment systems in a solitary work situation. The study focusses on the workers and service providers of Aguas do Algarve, S.A. (AdA) permanently in the facilities of the organization studied. A sample of 201 workers distributed according to the design: 2 (Isolation Period: short vs. long) X 2 (Distance: lowest vs. highest distance) was collected for the convenience. Data were collected using a questionnaire The results showed that it is the workers in situations of long periods and smaller distances that present lower values of physical and psychosocial safety. With respect to safety behaviors, the lowest means is observed in workers with the highest distance conditions. The correlation analysis shows significant values in the relationship between the safety climate and safety behaviors. Future studies should consider predictors of the safety climate and non-solitary workers, as well as, action research.
- Non-indigenous species in soft-sediments: are some estuaries more invaded than others?Publication . Cabral, Sara; Carvalho, Frederico; Gaspar, Miguel; Ramajal, Joao; Sa, Erica; Santos, Catia; Silva, Gilda; Sousa, Antonio; Costa, Jose Lino; Chainho, PaulaNon-indigenous species (NIS) are increasingly widespread and abundant in coastal areas, hence being considered indicators to assess the environmental status of marine waters under the Marine Strategy Framework Directive. However, information on the effects of biological invasions on species composition and abundance is still scarce, particularly for soft-sediment benthic communities, which remain poorly understood. Therefore, the present study aimed at monitoring the benthic communities of two Portuguese estuarine systems, with a particular focus on NIS. Sampling surveys were conducted at the Tagus and Sado estuaries, in three different years. Invertebrate communities were collected at sampling stations located along the estuarine gradient, using a clam dredge, and several water and sediment parameters were measured at the same locations. NIS represented nearly one fourth (23%) of the total observed individuals across all years and estuaries, with Ruditapes philippinarum accounting for 22% of the total abundance across estuaries and years. Although both estuaries presented a similar total number of species (91 at the Tagus and 81 at the Sado), three-fold more NIS were identified at the Tagus estuary. The frequency of occurrence of the NIS Crassostrea (Magallana) gigas, Mya arenaria and Panopeus occidentalis increased significantly over the three years at the Tagus estuary and decreased significantly for Dyspanopeus sayi from 2015 to 2018. The Tagus and Sado estuaries presented distinct and diverse communities, with the abundance of R. philippinarum being eleven-fold greater at the Tagus estuary than at the Sado estuary. This study provides a baseline list of the NIS occurring in two of the main Portuguese estuarine systems, as well as an approach to estimate NIS abundance, richness, frequency of occurrence and community diversity. Although most studies on NIS impacts have focused on single species, the assessment of the environmental status of marine waters requires that overall impacts of NIS on marine ecosystems are determined. This study indicated metrics that are appropriate to evaluate changes in soft-sediment benthic communities associated to the introduction of NIS.