Mapping and classification of ecologically sensitive marine habitats using unmanned aerial vehicle (UAV) imagery and object-based image analysis (OBIA)

Nowadays, emerging technologies, such as long-range transmitters, increasingly miniaturized components for positioning, and enhanced imaging sensors, have led to an upsurge in the availability of new ecological applications for remote sensing based on unmanned aerial vehicles (UAVs), sometimes referred to as “drones”. In fact, structure-from-motion (SfM) photogrammetry coupled with imagery acquired by UAVs offers a rapid and inexpensive tool to produce high-resolution orthomosaics, giving ecologists a new way for responsive, timely, and cost-effective monitoring of ecological processes. Here, we adopted a lightweight quadcopter as an aerial survey tool and object-based image analysis (OBIA) workflow to demonstrate the strength of such methods in producing very high spatial resolution maps of sensitive marine habitats. Therefore, three different coastal environments were mapped using the autonomous flight capability of a lightweight UAV equipped with a fully stabilized consumer-grade RGB digital camera. In particular we investigated a Posidonia oceanica seagrass meadow, a rocky coast with nurseries for juvenile fish, and two sandy areas showing biogenic reefs of Sabelleria alveolata. We adopted, for the first time, UAV-based raster thematic maps of these key coastal habitats, produced after OBIA classification, as a new method for fine-scale, low-cost, and time saving characterization of sensitive marine environments which may lead to a more effective and efficient monitoring and management of natural resource

Unmanned Aerial Systems (UASs) for Environmental Monitoring: A Review with Applications in Coastal Habitats

Nowadays the proliferation of small unmanned aerial systems or vehicles (UAS/Vs), formerly known as drones, coupled with an increasing interest in tools for environmental monitoring, have led to an exponential use of these unmanned aerial platforms for many applications in the most diverse fields of science. In particular, ecologists require data collected at appropriate spatial and temporal resolutions to describe ecological processes. For these reasons, we are witnessing the proliferation of UAV-based remote sensing techniques because they provide new perspectives on ecological phenomena that would otherwise be difficult to study. Therefore, we propose a brief review regarding the emerging applications of low-cost aerial platforms in the field of environmental sciences such as assessment of vegetation dynamics and forests biodiversity, wildlife research and management, map changes in freshwater marshes, river habitat mapping, and conservation and monitoring programs. In addition, we describe two applications of habitat mapping from UAS-based imagery, along the Central Mediterranean coasts, as study cases: (1) The upper limit of a Posidonia oceanica meadow was mapped to detect impacted areas, (2) high-resolution orthomosaic was used for supporting underwater visual census data in order to visualize juvenile fish densities and microhabitat use in four shallow coastal nurseries

Aquaculture and Restoration: Perspectives from Mediterranean Sea Experiences

In this paper, the different possibilities and innovations related to sustainable aquaculture in the Mediterranean area are discussed, while different maricultural methods, and the role of Integrated Multi-Trophic Aquaculture (IMTA) in supporting the exploitation of the ocean’s resources, are also reviewed. IMTA, and mariculture in general, when carefully planned, can be suitable for environmental restoration and conservation purposes. Aquaculture, especially mariculture, is a sector that is progressively increasing in parallel with the increase in human needs; however, several problems still affect its development, mainly in relation to the choice of suitable sites, fodder production, and the impact on the surrounding environment. A current challenge that requires suitable solutions is the implementation of IMTA. Unfortunately, some criticisms still affect this approach, mostly concerning the commercialization of new products such as invertebrates and seaweeds, notwithstanding their environmentally friendly character. Regarding the location of a suitable site, mariculture plans are currently displaced from inshore to offshore, with the aim of reducing the competition for space with other human activities carried out within coastal waters. Moreover, in open water, waste loading does not appear to be a problem, but high-energy waters increase maintenance costs. Some suggestions are given for developing sustainable mariculture in the Mediterranean area, where IMTA is in its infancy and where the scarce nutrients that characterize offshore waters are not suitable for the farming of both filter feeder invertebrates and macroalgae. From the perspective of coupling mariculture activity with restoration ecology, the practices suggested in this review concern the implementation of inshore IMTA, creating artificially controlled gardens, as well as offshore mussel farming coupled with artificial reefs, while also hypothesizing the possibility of the use of artificially eutrophized areas

Heavy metal accumulation capacity of Axinella damicornis (Esper, 1794) (Porifera, Demospongiae): a tool for bioremediation of polluted seawaters

A wide range of contaminants are continuously introduced into the aquatic environment and among these, heavy metals con- stitute one of the most dangerous groups because of their persistent nature, toxicity, tendency to accumulate in organisms and more still, they are non-degradable. Marine organisms such as sponges represent target species for the monitoring of heavy metal contamination due their filtering activity. This study aims to evaluate the retention capacity of lead and cadmium by the sponge Axinella damicornis under laboratory conditions. The sponges were exposed for 144 h to seawaters artificially polluted with lead (Pb) and cadmium (Cd) separately and with a mixture of the two metals. The final goal of the experiments was to evaluate the met- al uptake in the sponge body and efficiency of the sponge in removing the metals from seawater. In particular, the highest values of metal concentration in the sponges were recorded for Pb: this metal was found to be 6 times and 9 times more concentrated than Cd, respectively in the case of exposure to the single metal and to the combination of both metals. The metal concentrations found, especially for Pb, were much higher in A. damicornis than in other organisms investigated in the sea. Remarkable signs of stress and necrosis were recorded in the specimens when exposed to the combination of Pb and Cd, evidencing a synergistic effect of the metals mixture. This study paves adds knowledge on the contamination effects by heavy metals on the marine organisms and on the contribution from A. damicornis as efficient tool for bioremediation of polluted seawaters

Two cases study of fouling colonization patterns in the Mediterranean Sea in the perspective of integrated aquaculture systems

Fouling assemblage colonizing fish-farms is considered mostly to produce negative impacts causing financial loss. By contrast, large evidences emerged on the bioremediation role by biofouling associated to aquaculture facilities, even if the fouling assemblages thriving in the water column was poorly investigated. The aim of the present work was to investigate the macrofouling assemblages over one year of immersion, in order to single out the fouling species, which play the most remarkable role for the bioremediation of the marine areas affected by aquaculture activities. With this in mind, we studied the fouling community dynamics in two Mediterranean maricultural facilities, respectively in the Mar Grande of Taranto (Ionian Sea) and in the Gulf of Gaeta (Tyrrhenian Sea), using the same experimental design and time frame. Two experiments were carried out using artificial panels anchored to two finfish cages. The one-year old fouling communities in the two sites were compared at four seasons of immersion, four submersion durations and three depths, both communities from structural and functional points of view. Notwithstanding the quite similar species composition of fouling of the two sites, the biofouling showed the highest biodiversity in the Mar Grande of Taranto. In the Gulf of Gaeta mussels, Mytilus galloprovincialis, dominated at all the times and depths, whilst in the Mar Grande of Taranto they were especially abundant at the surface with the deepest panels being largely colonized by polychaete sabellids. The co-occurrence of the filter-feeders Mytilus-sabellids recorded in the Gulf of Taranto also highlighted the highest filtration capability. Our results suggest two different fouling assemblages as candidates for bioremediation in integrated multitrophic aquaculture facilities: both a monospecific system dominated by mussels and a multi-specific system with sabellids and mussels as most abundant filter-feeders

Biofouling Role in Mariculture Environment Restoration: An Example in the Mar Grande of Taranto (Mediterranean Sea)

none7The biodiversity of macrobenthic invertebrates of two artificial hard substrates close to a mariculture plant was assessed in order to understand the effect on the fouling community of an innovative Integrated Multi-Trophic Aquaculture (IMTA) system. The examined hard substrates were (i) vertical bare collectors that are placed around the cages as new colonizable substrates, which were investigated from the early colonization and (ii) artificial hard substrates already present under the cages analyzed over time to observe changes due to the action on the water column by filter feeder organisms colonizing the above vertical collectors. Overall, 186 taxa were collected (both the substrates), of which 99 as sessile habitat-former or structuring macroinvertebrates and 87 as associated fauna, mostly vagile forms. On the vertical collectors 121 taxa were collected, among which 44 sessile structuring species and 77 vagile-associated taxa; on the artificial hard substrates under the cages, 124 taxa were identified, 95 belong to the first category and 29 as associated taxa. The two analyzed substrates shared 43% of sessile species (40) and 22% of associated species (19). At the end of the first year of experimentation, the study revealed Sabella spallanzanii and mussels as the most abundant taxa. Lastly, the communities under the cages showed an increase in biodiversity after the placement of collectors. The changes were attributed to the decrease in particulate matter originating as wastes from the breeding cage, which was intercepted by the filter feeder community developed on the vertical collectors.openDaniele Arduini, Jacopo Borghese, Maria Flavia Gravina, Roberta Trani, Caterina Longo, Cataldo Pierri, Adriana GiangrandeArduini, Daniele; Borghese, Jacopo; Flavia Gravina, Maria; Trani, Roberta; Longo, Caterina; Pierri, Cataldo; Giangrande, Adrian

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Note tassonomiche ed ecologiche su Micromaldane Ornithochaeta (Polichaeta, Maldanidae), rinvenuta lungo le coste italiane meridionali

EnA massive presence of the species Micromaldane ornithochaeta Mesnil, 1897 is reported along the South Italian coast (Mediterranean Sea) associated to the sponge Geodia cydonium (Jameson). Up to now the species was considered rare along the Italian coast. A re-description of the species was reported together with a discussion on its ecological characteristics

Note tassonomiche ed ecologiche su Micromaldane ornithochaeta (Polychaeta, Maldanidae), rinvenuta lungo le coste italiane meridionali

A massive presence of the species Micromaldane ornithochaeta Mesnil, 1897 is reported along the South Italian coast associated to the sponge Geodia cydonium (Jameson). Up to now the species was considered rare along the Italian coast. A re-descriptionof the species was reported together with a discussion on its ecological characteristics