Quotas regulation is necessary but not sufficient to mitigate the impact of SCUBA diving in a highly visited marine protected area

When effectively managed, Marine Protected Areas (MPAs) can produce wide ecosystem benefits that can foster, directly and indirectly, local economies. Tourism is one of the sectors mainly benefited by the effect of conservation. SCUBA diving represents an important tourism activity, especially in the context of MPAs, where it is one of the few activities often fostered rather than limited, for its capacity to integrate environmental and socio-economic sustainability. However, SCUBA diving can also produce negative impacts on the environment when tourism frequentation exceeds a sustainable threshold, these potentially generating negative effects on the sector itself. In this study, we (1) investigated the impact of SCUBA diving in one of the most frequented diving areas of the Mediterranean Sea (Cabo de Palos - Islas Hormigas marine reserve), and (2) assessed the potential benefits over time related to the adoption of a regulation change for the diving activity (i.e., formally adoption of diving quotas). Specifically, we compared demographic (density of alive and dead colonies) and morphometric (height, width and complexity) characteristics of the false coral (Myriapora truncata) between dived and fully protected (non-dived) locations over four diving seasons (one before and three after the change in diving quotas). The density of alive colonies of the false coral was, on average, six times lower in dived locations compared to controls, highlighting a clear impact of SCUBA diving (consistent over time). Colonies were also significantly smaller in dived locations. The diving quotas produced a significant reduction of the ratio dead/total colonies in the dived locations soon after their adoption, but these benefits disappeared over the following years, possibly due to a gradual decline in operators' and divers' observance and concern, rather than an increasing number of dives. This suggests that the adoption of effective regulations is crucial for the environmental sustainability of diving tourism in protected areas and can provide positive effects, but an effort is needed to ensure that compliance is consistent over time, and that low-impact diving practices are adopted by this important recreational sector

Detection of protection benefits for predatory fishes depends on census methodology

Marine protected areas (MPAs) are used as fisheries management and conservation tools. Well-enforced no-take zones allow the rebuilding of natural populations of exploited species; however, there is still controversy on the role of buffer zones. The effectiveness of MPAs could be underestimated, as fish population assessments depend largely on traditional methodologies that have difficulties in detecting predatory fish because of their low abundances, their patchy distribution, and their reaction to the presence of divers. The performance of different census methods was compared in assessing the protection benefits for large predatory fishes under different protection levels (i.e. no-take and buffer zones) in five Mediterranean MPAs. Specifically, conventional strip transects (CSTs, 50 × 5 m2) and tracked roaming transects combined with distance sampling (TRT + DS, variable lengths) were compared, including a series of TRT-derived estimators with variable transect lengths and fixed widths of 20, 10, and 6 m (TRT20, TRT10, and TRT6, respectively). Additionally, the effectiveness of the MPAs studied and protection levels for conserving large predatory species was evaluated. Transects covering larger areas (i.e. TRT + DS and TRT20) allowed the detection of a greater number of species and yielded more accurate estimates of density and biomass than transects of narrower fixed widths, particularly the CSTs, which were associated with the lowest richness detection capability, accuracy, and precision. On average, both no-take zones and buffer zones appeared effective for the conservation of predatory fishes, indicating that multiple protection areas were ecologically effective. Differences between MPAs were also observed, however, probably arising from both local environmental and management factors. We suggest the implementation of methodologies with larger transects for the study of large predatory fish, combined with CSTs for the rest of the fish community, in order to avoid biases in predatory population assessments, which are key indicators of MPA effectiveness

Study of Oxygen Reactivity in La1-x Sr (x) CoO3-delta Perovskites for Total Oxidation of Toluene

AIR:SURFACES+FGAThe total oxidation of toluene is studied over catalytic systems based on perovskite with general formula AA'CoO3-delta (A = La, A' = Sr). The systematic and progressive substitution of La3+ by Sr2+ cations in the series (La1-x Sr (x) CoO3-delta system) of the perovskites have been studied to determine their influence in the final properties of these mixed oxides and their corresponding reactivity performance for the total oxidation of toluene as a model volatile organic compound with detrimental effects for health and environment. The structure and morphology of the samples before and after reaction have been characterized by XRD, BET and FE-SEM techniques. Additional experiments of temperature programmed desorption of O-2 in vacuum and reduction in H-2 were also performed to identify the main surface oxygen species and the reducibility of the different perovskites. It is remarkable that the La1-x Sr (x) CoO3-delta series presents better catalytic performance for the oxidation of toluene, with lower values for the T-50 (temperature of 50 % toluene conversion) than the previously studied LaNi1-y Co (y) O-3 series

Reactivity of LaNi1-y Co (y) O3-delta Perovskite Systems in the Deep Oxidation of Toluene

Pereniguez, R. Hueso, J. L. Holgado, J. P. Gaillard, F. Caballero, A.In the present work we have evaluated the oxidation of toluene over different lanthanum perovskites with a general composition of LaNi1-y Co (y) O3-delta. These catalysts, prepared by a spray pyrolysis method, have been characterised by XRD, BET and FE-SEM techniques. Additional experiments of temperature programmed desorption of O-2, reduction in H-2 and X-ray absorption spectroscopy were also performed in order to identify the main surface oxygen species and the reducibility of the different perovskites. The catalytic behaviour toward the oxidation of toluene (as a model for VOCs compounds) was evaluated in the range 100-600 A degrees C, detecting a total conversion for all the samples below 400 A degrees C and higher activities for the cobalt-containing perovskites. The catalytic behaviour of these samples is consistent with a suprafacial mechanism, with the alpha-type oxygen playing an active role in the oxidation reaction

Síntesis y caracterización de perovskitas tipo La1-xSrxB1-yBy´O3 (B = Ni; B´= Co) en procesos de oxidación total de tolueno

internationa

Systematic literature review on the state of the art and future research work in anonymous communications systems

Privacy is an important research topic due to its implications in society. Among the topics covered by privacy, we can highlight how to establish anonymous communications. During the latest years we have seen an important research in this field. In order to know what the state of the art in the research in anonymous communication systems (ACS) is, we have developed a systematic literature review (SLR). Namely, our SLR analyzes several issues: activity performed in the field, major research purposes, findings, what the most ACS study, the limitations of current research, how is leading the research in this field and the most highly-cited articles. Our SLR provides an analysis on 203 papers found in conferences and journals focused on anonymous communications systems between 2011 and 2016. Thus, our SLR provides an updated view on the status of the research in the field and the different future topics to be addressed