Biology of Parrotfishes

Parrotfish are found on almost every coral reef in the world. This ubiquity and uniqueness of their feeding action make them one of the most important groups of fishes within coral reef ecosystems. But why, exactly, are parrotfish so important to reefs? Can the evolution of a particular jaw morphology and feeding action really have had such a large impact on the health and functioning of the world's coral reefs? This book introduces the reader to this fascinating group of fishes (Labridae, Scarinae), from the morphological innovation of a jaw that has the power to bite through solid calcium carbonate, to the threats currently faced by parrotfish populations around the world. It contains new insights into their diet and food processing ability, and lifehistories, and concludes with an overview of emerging and future research directions

Simulation of a flash-flood event over the Adriatic Sea with a high-resolution atmosphere–ocean–wave coupled system

On the morning of September 26, 2007, a heavy precipitation event (HPE) affected the Venice lagoon and the neighbouring coastal zone of the Adriatic Sea, with 6-h accumulated rainfall summing up to about 360 mm in the area between the Venetian mainland, Padua and Chioggia. The event was triggered and maintained by the uplift over a convergence line between northeasterly flow from the Alps and southeasterly winds from the Adriatic Sea. Hindcast modelling experiments, using standalone atmospheric models, failed to capture the spatial distribution, maximum intensity and timing of the HPE. Here we analyze the event by means of an atmosphere-wave-ocean coupled numerical approach. The combined use of convection permitting models with grid spacing of 1 km, high-resolution sea surface temperature (SST) fields, and the consistent treatment of marine boundary layer fluxes in all the numerical model components are crucial to provide a realistic simulation of the event. Inaccurate representations of the SST affect the wind magnitude and, through this, the intensity, location and time evolution of the convergence zone, thus affecting the HPE prediction. © 2021, The Author(s)

Growth response and body composition of sharpsnout sea bream (Diplodus puntazzo) fed a high energy diet with different protein levels.

A study was undertaken to determine the effect of a high energy diet with two different protein levels on growth, feed efficiency and whole body composition of sharpsnout sea bream (Diplodus puntazzo). Two isoenergetic diets (24.1-24.7 MJ Kg-1 dry weight) with two different protein levels (46.7 and 52.5 % dry weight) were fed to satiety to duplicate groups of 300 fish (initial body weight 27.7 \ub1 0.2 g) for 94 days. At the end of the experiment, the fish fed 52.5 % protein showed a statistically higher (P < 0.05) daily intake rate (DIR) of feed. Feed conversion rate (FCR) was similar among groups. Whole body composition was similar among treatments while the high enrgy level of the diets significantly modified lipid and moisture content in comparison with fish at the beginning of the experiment. Protein efficiency ratio (PER), gross protein efficiency (GPE) of fish fed 46.7 % protein diet were statistically higher than those for the other diet. It may be concluded that the diet with a lower protein level has given better protein utilization and a protein sparing effect but tended to result in reduced weight gain and feed intake, when compared with diet containing higher protein levels

Coupled wave-2D hydrodynamics modeling at the Reno River mouth (Italy) under climate change scenarios

This work presents the results of the numerical study implemented for the natural area of Lido di Spina, a touristic site along the Italian coast of the North Adriatic Sea, close to the mouth of River Reno. High-resolution simulations of nearshore dynamics are carried out under climate change conditions estimated for the site. The adopted modeling chain is based on the implementation of multiple-nested, open-source numerical models. More specifically, the coupled wave-2D hydrodynamics runs, using the open-source TELEMAC suite, are forced at the offshore boundary by waves resulting from the wave model (SWAN) simulations for the Adriatic Sea, and sea levels computed following a joint probability analysis approach. The system simulates presentday scenarios, as well as conditions reflecting the high IPCC greenhouse concentration trajectory named RCP8.5 under predicted climate changes. Selection of sea storms directed from SE (Sirocco events) and E-NE (Bora events) is performed together with Gumbel analysis, in order to define ordinary and extreme sea conditions. The numerical results are here presented in terms of local parameters such as wave breaking position, alongshore currents intensity and direction and flooded area, aiming to provide insights on how climate changes may impact hydrodynamics at a site scale. Although the wave energy intensity predicted for Sirocco events is expected to increase only slightly, modifications of the wave dynamics, current patterns, and inland flooding induced by climate changes are expected to be significant for extreme conditions, especially during Sirocco winds, with an increase in the maximum alongshore currents and in the inundated area compared to past conditions. \ua9 2018 by the authors

Resistência de porta-enxertos de maracujazeiro a Fusarium spp em Terra Nova do Norte/MT.

Com objetivo de estudar o comportamento de porta-enxertos de maracujazeiro em relação à resistência a Fusarium spp, no ano de 2012, em Terra Nova do Norte/MT, foram conduzidos dois ensaios, por três anos, nas propriedades do Sr. Pedro e do Sr. Maciel, com histórico de fusariose em maracujazeiro. As mudas foram conduzidas no viveiro da COOPERNOVA e foram utilizados os porta-enxertos dos seguintes genótipos: (T1) CPAC M5-H-67, (T2) CPAC MJ-H-65, (T3) CPAC MJ-H-66, (T4) Gigante Amarelo, (T5) CPAC MJ-45-03, CPAC MJ-H-68, (T6) P. edulis (PE), (T7) Passiflora nitida e (T8) P. alata, sob a copa da cultivar BRS Gigante Amarelo. Os materiais foram fornecidos pela Embrapa Cerrados, pelo Dr. Dr. Givanildo Roncato e COOPERNOVA. O delineamento utilizado foi em blocos ao acaso. Cada unidade experimental foi constituída de quatro plantas com espaçamento de 4 m entre plantas e 3 m entre ruas Os tratamentos 6 e 8 foram as testemunhas suscetível e resistente, respectivamente. Na propriedade do Sr. Pedro, onde o solo é mais argiloso, as plantas começaram a apresentar sintomas de fusariose mais cedo, em relação à área do Sr. Maciel, que é mais arenosa. Os tratamentos: 4 (Gigante Amarelo) e 6 (P. edulis) foram os que apresentaram maior mortalidade de plantas, nas duas propriedades, o que já era esperado, uma vez que são materiais extremamente suscetíveis à fusariose. Os tratamentos 1 (CPAC M5-H-67), 3 (CPAC MJ-H-66), 5 (CPAC MJ-45-03) e 8 (P. alata), apresentaram entre de 25 e 50% de mortalidade, na propriedade do Sr. Maciel, possivelmente, como resultado do manejo, uma vez que as mesmas apresentaram mortalidade menor na área do Sr. Pedro, mesmo esta possuindo solo mais argiloso. Os tratamentos 2 (CPAC MJ-H-65); e 7 (P. nítida) apresentaram menor mortalidade ao longo das avaliações, nas duas propiedades. O tratamento 8 (P. alata), não apresentou mortes de plantas na propriedade do Sr. Pedro, o que era esperado, uma vez que esse material é resistente a fusariose do maracujazeiro

Optimal index related to the shoreline dynamics during a storm: the case of Jesolo beach

The paper presents an application of shoreline monitoring aimed at understanding the response of a beach to single storms and at identifying its typical behaviour, in order to be able to predict shoreline changes and to properly plan the defence of the shore zone. On the study area, in Jesolo beach (northern Adriatic Sea, Italy), a video monitoring station and an acoustic wave and current profiler were installed in spring 2013, recording, respectively, images and hydrodynamic data. The site lacks previous detailed hydrodynamic and morphodynamic data. Variations in the shoreline were quantified in combination with available near-shore wave conditions, making it possible to analyse the relationship between the shoreline displacement and the wave features. Results denote characteristic patterns of beach response to storm events, and highlight the importance of improving beach protection in this zone, notwithstanding the many interventions experimented in the last decades. A total of 31 independent storm events were selected during the period October 2013–October 2014, and for each of them synthetic indexes based on storm duration, energy and maximum wave height were developed and estimated. It was found that the net shoreline displacements during a storm are well correlated with the total wave energy associated to the considered storm by an empirical power law equation. A sub-selection of storms in the presence of an artificial dune protecting the beach (in the winter season) was examined in detail, allowing to conclude that the adoption of this coastal defence strategy in the study area can reduce shoreline retreat during a storm. This type of intervention can sometimes contribute to prolonging overall stability not only in the replenished zone but also in downdrift areas. The implemented methodology, which confirms to be economically attractive if compared to more traditional monitoring systems, proves to be a valuable system to monitor beach erosive processes and provide detailed indications on how to better plan beach-maintenance activities. The presented methodology and the proposed results can therefore be used as a basis for improving the collaboration between coastal scientists and managers to solve beach erosion problems, in locations where data are scattered and sporadic.</p