Microplastics alter the functioning of marine microbial ecosystems.

Microplastics pervade ocean ecosystems. Despite their effects on individuals or populations are well documented, the consequences of microplastics on ecosystem functioning are still largely unknown. Here, we show how microplastics alter the structure and functioning of pelagic microbial ecosystems.

Scientists' call to action: Microbes, planetary health, and the Sustainable Development Goals.

Microorganisms, including bacteria, archaea, viruses, fungi, and protists, are essential to life on Earth and the functioning of the biosphere. Here, we discuss the key roles of microorganisms in achieving the United Nations Sustainable Development Goals (SDGs), highlighting recent and emerging advances in microbial research and technology that can facilitate our transition toward a sustainable future. Given the central role of microorganisms in the biochemical processing of elements, synthesizing new materials, supporting human health, and facilitating life in managed and natural landscapes, microbial research and technologies are directly or indirectly relevant for achieving each of the SDGs.

Resistance to freezing conditions of endemic Antarctic polychaetes is enhanced by cryoprotective proteins produced by their microbiome.

The microbiome plays a key role in the health of all metazoans. Whether and how the microbiome favors the adaptation processes of organisms to extreme conditions, such as those of Antarctica, which are incompatible with most metazoans, is still unknown. We investigated the microbiome of three endemic and widespread species of Antarctic polychaetes: , , and .

Microbes as marine habitat formers and ecosystem engineers.

Despite their small individual size, marine prokaryotic and eukaryotic microbes can form large 3D structures and complex habitats. These habitats contribute to seafloor heterogeneity, facilitating colonization by animals and protists. They also provide food and refuge for a variety of species and promote novel ecological interactions.

Fungal Abundance and Diversity in the Mariana Trench, the Deepest Ecosystem on Earth.

Hadal trenches host abundant and diversified benthic prokaryotic assemblages, but information on benthic fungi is still extremely limited. We investigated the fungal abundance and diversity in the Challenger Deep (at ca. 11,000 m depth) and the slope of the Mariana Trench in comparison with three sites of the adjacent abyssal plain.

Viral Diversity in Benthic Abyssal Ecosystems: Ecological and Methodological Considerations.

Viruses are the most abundant 'biological entities' in the world's oceans. However, technical and methodological constraints limit our understanding of their diversity, particularly in benthic abyssal ecosystems (>4000 m depth). To verify advantages and limitations of analyzing virome DNA subjected either to random amplification or unamplified, we applied shotgun sequencing-by-synthesis to two sample pairs obtained from benthic abyssal sites located in the North-eastern Atlantic Ocean at ca.

Effects of seagrass (Cymodocea nodosa) restoration on nematode biodiversity.

Seagrass meadows are hot spots of biodiversity and play a key role in the provisioning of ecosystem goods and services but are often subjected to a regression due to a combination of multiple anthropogenic and climate-induced impacts. The ecological restoration of these habitat-forming species is a priority to reverse biodiversity loss and for the recovery of key ecosystem functions. Here we investigated the effects of seagrass (Cymodocea nodosa) restoration action on benthic biodiversity recovery assessed by a time-series analysis carried out for one year.

Bioaccumulation and biomagnification of heavy metals in marine micro-predators.

Nematodes represent >3/5 of the abundance of the world's metazoans and usually account for nearly 90% of the total benthic fauna, playing a key ecological role in the benthic ecosystem functioning on a global scale. These small metazoans include a relevant number of microscopic predators and, in turn, are the most abundant preys of macro-megafauna and fish juveniles thus playing a key role in marine food webs. Here, using two independent approaches, we test the bioaccumulation in marine nematodes of several heavy metals present in contaminated sediments.

Rhodobacteraceae dominate the core microbiome of the sea star (Koehler, 1906) in two opposite geographical sectors of the Antarctic Ocean.

Microbiota plays essential roles in the health, physiology, and in adaptation of marine multi-cellular organisms to their environment. In Antarctica, marine organisms have a wide range of unique physiological functions and adaptive strategies, useful for coping with extremely cold conditions. However, the role of microbiota associated with Antarctic organisms in such adaptive strategies is underexplored.

Encapsulated in sediments: eDNA deciphers the ecosystem history of one of the most polluted European marine sites.

The Anthropocene is characterized by dramatic ecosystem changes driven by human activities. The impact of these activities can be assessed by different geochemical and paleontological proxies. However, each of these proxies provides only a fragmentary insight into the effects of anthropogenic impacts.

Microbiome network in the pelagic and benthic offshore systems of the northern Adriatic Sea (Mediterranean Sea).

Because of their recognized global importance, there is now the urgent need to map diversity and distribution patterns of marine microbial communities. Even if available studies provided some advances in the understanding the biogeographical patterns of marine microbiomes at the global scale, their degree of plasticity at the local scale it is still underexplored, and functional implications still need to be dissected. In this scenario here we provide a synoptical study on the microbiomes of the water column and surface sediments from 19 sites in a 130 km area located 13.

Assessing the eco-compatibility of new generation sunscreen products through a combined microscopic-molecular approach.

There is now unequivocal evidence that sunscreen can severely affect marine ecosystems. However, so far, most studies have focused on the impact of single sunscreen ingredients rather than on the whole sunscreen products, which are released into the marine environment. In the present work, we investigated the ecological impact of six formulations, which represent the "new generation" organic UV filters such as diethylamino hydroxybenzoyl hexyl benzoate (DHHB), methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT), ethylhexyl triazone (EHT), and bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT), which are progressively replacing the "old generation" organic UV filters (e.

Effects of Local Acidification on Benthic Communities at Shallow Hydrothermal Vents of the Aeolian Islands (Southern Tyrrhenian, Mediterranean Sea).

The Aeolian Islands (Mediterranean Sea) host a unique hydrothermal system called the "Smoking Land" due to the presence of over 200 volcanic CO-vents, resulting in water acidification phenomena and the creation of an acidified benthic environment. Here, we report the results of a study conducted at three sites located at ca. 16, 40, and 80 m of depth, and characterized by CO emissions to assess the effects of acidification on meio- and macrobenthic assemblages.

Changes in coral forest microbiomes predict the impact of marine heatwaves on habitat-forming species down to mesophotic depths.

Global warming is causing the increase in intensity and frequency of heatwaves, which are often associated with mass mortality events of marine organisms from shallow and mesophotic rocky habitats, including gorgonians and other sessile organisms. We investigated the microbiome responses of the gorgonians Paramuricea clavata, Eunicella cavolini, and the red coral Corallium rubrum to the episodic temperature anomalies detected in the North Western Mediterranean, during August 2011. Although the investigated corals showed no signs of visible necrosis, the abundance of associated Bacteria and Archaea increased with increasing seawater temperature, suggesting their temperature-dependent proliferation.

Local Environmental Conditions Promote High Turnover Diversity of Benthic Deep-Sea Fungi in the Ross Sea (Antarctica).

Fungi are a ubiquitous component of marine systems, but their quantitative relevance, biodiversity and ecological role in benthic deep-sea ecosystems remain largely unexplored. In this study, we investigated fungal abundance, diversity and assemblage composition in two benthic deep-sea sites of the Ross Sea (Southern Ocean, Antarctica), characterized by different environmental conditions (i.e.

Organic enrichment can increase the impact of microplastics on meiofaunal assemblages in tropical beach systems.

The cumulative impact of microplastic and organic enrichment is still largely unknown. Here, we investigated the microplastic contamination, the organic enrichment and their effects on meiofaunal distribution and diversity in two islands of the Maldivian archipelago: one more pristine, and another strongly anthropized. Field studies were coupled with manipulative experiments in which microplastic polymers were added to sediments from the non-anthropized island (i.

Early-stage anomalies in the sea urchin (Paracentrotus lividus) as bioindicators of multiple stressors in the marine environment: Overview and future perspectives.

The morphological anomalies of the early development stages of the sea urchin Paracentrotus lividus, caused by exposure to environmental stressors, are used as biomarker in ecotoxicological and ecological investigations. Here, we reviewed the available literature and classified the embryo and larval anomalies identified so far, to highlight potential commonalities or differences related to the biological action of the different stressors and their ecological impact. Morphological anomalies are influenced by a) the developmental stage of exposure to stressors; b) the intensity of the stress; c) the intra- and inter-cellular mechanisms affected by the exposure to environmental agents.

Diversity, Ecological Role and Biotechnological Potential of Antarctic Marine Fungi.

The Antarctic Ocean is one of the most remote and inaccessible environments on our planet and hosts potentially high biodiversity, being largely unexplored and undescribed. Fungi have key functions and unique physiological and morphological adaptations even in extreme conditions, from shallow habitats to deep-sea sediments. Here, we summarized information on diversity, the ecological role, and biotechnological potential of marine fungi in the coldest biome on Earth.

Ocean Acidification Induces Changes in Virus-Host Relationships in Mediterranean Benthic Ecosystems.

Acidified marine systems represent "natural laboratories", which provide opportunities to investigate the impacts of ocean acidification on different living components, including microbes. Here, we compared the benthic microbial response in four naturally acidified sites within the Southern Tyrrhenian Sea characterized by different acidification sources (i.e.

Highly Contaminated Marine Sediments Can Host Rare Bacterial Taxa Potentially Useful for Bioremediation.

Coastal areas impacted by high anthropogenic pressures typically display sediment contamination by polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). Microbial-based bioremediation represents a promising strategy for sediment reclamation, yet it frequently fails due to poor knowledge of the diversity and dynamics of the autochthonous microbial assemblages and to the inhibition of the target microbes in the contaminated matrix. In the present study, we used an integrated approach including a detailed environmental characterization, high-throughput sequencing and culturing to identify autochthonous bacteria with bioremediation potential in the sediments of Bagnoli-Coroglio (Gulf of Naples, Mediterranean Sea), a coastal area highly contaminated by PAHs, aliphatic hydrocarbons and HMs.

Multiple declines and recoveries of Adriatic seagrass meadows over forty years of investigation.

This paper investigated the long-term changes (from 1973 to 2013) of the seagrass meadows of Zostera marina, Zostera noltei and Cymodocea nodosa in the Adriatic Sea subjected to multiple pressures. We examined the changes of the meadows by means of field data collection, observations and analysis of aerial photography to identify the most important drivers of habitat loss. The major decline of seagrass extension observed from 1973 to 1989, was primarily driven by urban development, and by the increase of the blue tourism.