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We studied the role of natural (common reed) and artificial substrata (bamboo) in structuring the abundance and taxonomic composition of periphyton assemblages. Investigations were conducted in a shallow, hypertrophic lake situated in the area of Polesie Lubelskie (Eastern Poland). Periphyton communities (algae, ciliates, small metazoa and chironomids) on both types of substratum were sampled monthly, from May to November of 2007. Water samples for chemical analysis were collected together with biological samples. We selected the group of ten environmental variables which are the most important in determining the habitat conditions in highly eutrophic lakes: temperature, Secchi disc visibility, conductivity, dissolved oxygen, periphytic chlorophyll-a, N-NO3, N-NH4, TP, P-PO4 and total organic carbon (TOC). The abundances of periphytic algae, ciliates, metazoa and chironomids were significantly affected by season and substrate. On natural substrata, in all studied months, periphyton communities showed higher abundances. The results of PCA analysis confirmed the distinction between periphyton communities on natural and artificial substrata. The Monte Carlo permutation test showed that the periphyton communities on common reed were the most significantly affected by temperature, N-NO3, Secchi disc visibility and TOC. The communities on artificial substrata were significantly influenced by temperature, P-PO4 and TOC. On natural substrata biomass of periphytic algae was significantly negatively correlated with abundances of all groups of potential grazers (ciliates, metazoa, chironomids). On artificial substrata the relations between components of periphytic food web were stronger; correlation coefficients between algae, protists and chironomids were significant at P<0.01. The results of analysis indicate that periphytic algae can play an important role as food source for higher trophic levels. These interactions are less significant on natural (reed) substrata, where algae during their growth may use nutrients releasing by plants. On inert substrata intensive feeding activity of grazers (ciliates, metazoan, chironomids) can markedly reduce algal biomass and affect their taxonomic composition.

Microbial biofilms are biological structures composed of surface-attached microbial communities embedded in an extracellular polymeric matrix. In aquatic environments, the microbial colonization of submerged surfaces is a complex process involving several factors, related to both environmental conditions and to the physical-chemical nature of the substrates. Several studies have addressed this issue; however, more research is still needed on microbial biofilms in marine ecosystems. After a brief report on environmental drivers of biofilm formation, this study reviews current knowledge of microbial community attached to artificial substrates, as obtained by experiments performed on several material types deployed in temperate and extreme polar marine ecosystems. Depending on the substrate, different microbial communities were found, sometimes highlighting the occurrence of species-specificity. Future research challenges and concluding remarks are also considered. Emphasis is given to future perspectives in biofilm studies and their potential applications, related to biofouling prevention (such as cell-to-cell communication by quorum sensing or improved knowledge of drivers/signals affecting biological settlement) as well as to the potential use of microbial biofilms as sentinels of environmental changes and new candidates for bioremediation purposes.

Efforts to restore coral reefs usually involve transplanting asexually propagated fast-growing corals. However, this approach can lead to outplanted populations with low genotypic diversity, composed of taxa susceptible to stressors such as marine heatwaves. Sexual coral propagation leads to greater genotypic diversity, and using slow-growing, stress-tolerant taxa may provide a longer-term return on restoration efforts due to higher outplant survival. However, there have been no reports to date detailing the full cycle of rearing stress-tolerant, slow-growing corals from eggs until sexual maturity. Here, we sexually propagated and transplanted two massive slow-growing coral species to examine long-term success as part of reef restoration efforts. Coral spat were settled on artificial substrates and reared in nurseries for approximately two years, before being outplanted and monitored for survivorship and growth for a further four years. More than half of initially settled substrates supported a living coral following nursery rearing, and survivorship was also high following outplantation with yields declining by just 10 to 14% over four years. At 6-years post-fertilisation over 90% of outplanted corals were reproductively mature, demonstrating the feasibility of restoring populations of sexually mature massive corals in under a decade. Although use of slower growing, stress tolerant corals for reef restoration may provide a longer-term return on investment due to high post-transplantation survival rates, considerable time is required to achieve even modest gains in coral cover due to their relatively slow rates of growth. This highlights the need to use a mix of species with a range of life-history traits in reef restoration and to improve survivorship of susceptible fast-growing taxa that can generate rapid increases in coral cover.

Artificial substrata are common features in the inter- and shallow subtidal of the highly urbanized southern Persian/Arabian Gulf (PAG). Sometimes placed as artificial reefs, their benefits and integration into the local ecology often remain unclear. Temporal change in cover and composition of fauna/flora, focusing on corals, were investigated on the outer breakwater of Palm Jebel Ali (PJA; UAE), and 10 natural reefs in southern PAG from 2008 to 2024. The benthic community on PJA from 2008 to 2010 was characterized by bare rock, algal turfs and increasing cover by corals, bivalves and other invertebrates until 5 years after establishment in 2007, when it became coral-dominated. Coral cover declined from 2014 (PJA 68%; PAG reefs 40%) to 2024 (PJA 2%, PAG reefs 3%) and turf algae cover increased (2024: PJA 79%, PAG reefs 72%). Changes in bivalves and other invertebrates were subtle. Coral dominance on PJA changed from Porites spp. in 2008 to merulinid ( Cyphastraea until 2014, then Platygyra ). Acropora disappeared from 2015 on PJA and most PAG reefs. Heat exceeded the coral bleaching threshold in 2012, 2015, 2020 and the mortality threshold in 2017, 2018, 2021, 2023, 2024. Heat stress negatively correlated with coral survival (GLM) and community composition changed along the heat stress gradient (CCA) on both PJA and PAG reefs. Ocean heat caused similar community changes on artificial and natural substrata.

Stomatal guard cells control leaf CO2 intake and concomitant water loss to the atmosphere. When photosynthetic CO2 assimilation is limited and the ratio of CO2 intake to transpiration becomes suboptimal, guard cells, sensing the rise inCO2 concentration in the substomatal cavity, deflate and the stomata close. Screens for mutants that do not close in response to experimentally imposed high CO2 atmospheres identified the guard cell-expressed Slowly activating anion channel, SLAC1, as the key player in the regulation of stomatal closure. SLAC1 evolved, though, before the emergence of guard cells. In Arabidopsis, SLAC1 is the founder member of a family of anion channels, which comprises four homologues. SLAC1 and SLAH3 mediate chloride and nitrate transport in guard cells, while SLAH1, SLAH2 and SLAH3 are engaged in root nitrate and chloride acquisition, and anion translocation to the shoot. The signal transduction pathways involved in CO2, water stress and nutrient-sensing activate SLAC/SLAH via distinct protein kinase/phosphatase pairs. In this review, we discuss the role that SLAC/SLAH channels play in guard cell closure, on the one hand, and in the root–shoot continuum on the other, along with the molecular basis of the channels’ anion selectivity and gating.

Surface colonization in seawater first corresponds to the selection of specific microbial biofilm communities. By coupling flow cytometry, microscopy and high throughput sequencing (HTS, 454 pyrosequencing) with artificial surfaces and environmental analyses, we intend to identify the contribution of biofilm community drivers at two contrasted French sites, one temperate and eutrophic (Lorient, Atlantic coast) and the other at a mesotrophic but highly contaminated bay (Toulon, North-Western Mediterranean Sea). Microbial communities were shaped by high temperatures, salinity and lead at Toulon by but nutrients and DOC at Lorient. Coatings including pyrithione exhibited a significant decrease of their microbial densities except for nanoeukaryotes. Clustering of communities was mainly based on the surface type and secondly the site, whereas seasons appeared of less importance. The in-depth HTS revealed that γ- and α-proteobacteria, but also Bacteroidetes, dominated highly diversified bacterial communities with a relative low β-diversity. Sensitivity to biocides released by the tested antifouling coatings could be noticed at different taxonomic levels: the percentage of Bacteroidetes overall decreased with the presence of pyrithione, whereas the α/γ-proteobacteria ratio decreased at Toulon when increased at Lorient. Small diatom cells (Amphora and Navicula spp.) dominated on all surfaces, whereas site-specific sub-dominant taxa appeared clearly more sensitive to biocides. This overall approach exhibited the critical significance of surface characteristics in biofilm community shaping.

The failure of breeding attempts is a major hindrance to bird reproduction, making nest site choice under strong selective pressure. Urbanization may offer lower risk of nest predation to certain bird species, but the impact of using anthropogenic structures as nesting sites on parental fitness is seldom studied. We studied the effect of anthropogenic substrates and brood parasitism by the shiny cowbird Molothrus bonariensis on the nest success of a Neotropical songbird, the pale‐breasted thrush Turdus leucomelas. We monitored 263 nesting attempts between 2017 and 2020 to estimate daily survival rate (DSR), which represents the probability of a given nest surviving until the next day. DSR was modelled as a response variable in function of substrate type (plants as ‘natural' or human buildings as ‘artificial') and brood parasitism as fixed factors, using as covariates year, a linear and a quadratic seasonal trends. Additionally, we tested the effect of these same explanatory variables on the number of fledglings per nest using a generalized linear mixed‐effects model. Most nests (78.7%) were placed in artificial substrates and apparent nest success (i.e. the percentage of nesting attempts that produced at least one thrush fledgling) was higher in artificial (50.2%) than in natural substrates (37.5%). DSR was higher for nests in artificial than in natural substrates regardless of cowbird parasitism, whereas the number of fledglings per nest was higher both in artificial substrates and for nests without cowbird parasitism. We highlight that nesting in buildings significantly increases parental fitness in pale‐breasted thrushes, which may favor their settlement in cities and potentially drive the evolution of this breeding behavior in urban birds.

This study presents the first documented observation of polyp bailout in the red tree coral, Primnoa pacifica , an ecologically important species that forms dense aggregations in the North Pacific. Colonies exposed to environmental and physical stress during a collection event showed polyp detachment, with bailed polyps reattaching to an artificial substrate after two weeks. This process, similar to asexual reproduction, likely presents an acute stress response. Additionally, it facilitates both local and long-distance dispersal, particularly in the high-current environments this species inhabits. In fjord populations where gamete maturation appears incomplete, polyp bailout may provide an alternative mechanism for recruitment into deeper, more favorable habitats. Marine ecosystems are under increasing pressure from environmental change and human activities, where adverse conditions are becoming more frequent and intense. Polyp bailout may play a role in the distribution of P. pacifica by enabling individuals to avoid acute stressors.

Coastal landscapes are being transformed as a consequence of the increasing demand for infrastructures to sustain residential, commercial and tourist activities. Thus, intertidal and shallow marine habitats are largely being replaced by a variety of artificial substrata (e.g. breakwaters, seawalls, jetties). Understanding the ecological functioning of these artificial habitats is key to planning their design and management, in order to minimise their impacts and to improve their potential to contribute to marine biodiversity and ecosystem functioning. Nonetheless, little effort has been made to assess the role of human disturbances in shaping the structure of assemblages on marine artificial infrastructures. We tested the hypothesis that some negative impacts associated with the expansion of opportunistic and invasive species on urban infrastructures can be related to the severe human disturbances that are typical of these environments, such as those from maintenance and renovation works. Maintenance caused a marked decrease in the cover of dominant space occupiers, such as mussels and oysters, and a significant enhancement of opportunistic and invasive forms, such as biofilm and macroalgae. These effects were particularly pronounced on sheltered substrata compared to exposed substrata. Experimental application of the disturbance in winter reduced the magnitude of the impacts compared to application in spring or summer. We use these results to identify possible management strategies to inform the improvement of the ecological value of artificial marine infrastructures. We demonstrate that some of the impacts of globally expanding marine urban infrastructures, such as those related to the spread of opportunistic, and invasive species could be mitigated through ecologically-driven planning and management of long-term maintenance of these structures. Impact mitigation is a possible outcome of policies that consider the ecological features of built infrastructures and the fundamental value of controlling biodiversity in marine urban systems.

Thousands of tonnes of artificial substrate have been deployed across the Gulf of Thailand in recent decades for the purpose of habitat creation and reef restoration. At the island of Koh Tao, these were mostly deployed between 2011 and 2017. Field surveys conducted in 2018–19 (an average of 44 months post deployment) at the island revealed considerable disparity in the community structures of scleractinian corals with recruit communities from artificial reefs and natural giant clam shells differing significantly from mature communities (reefs and pinnacles). Despite multiple biotic and abiotic variables being tested, no single explanation was found, and thus the findings were evaluated in the context of multiple hypotheses. In this study, we present findings from a repeated assessment of the same sites and substrates, carried out in 2023 (an average of 102 months post deployment), with significant differences in scleractinian recruit communities between survey periods, and again when compared with natural reefs and pinnacles. Based on a new dataset of 5442 coral recruits (clam shells and artificial reefs) and 2.46 km of reef and pinnacle transect data, we observed a significant increase in the heterogeneity of recruit communities on artificial reefs, with clear indications of convergence with mature reef communities. Meanwhile on natural substrates (reefs, pinnacles and shells), we observed proportionally little difference in communities between surveys (with some exceptions such as an increase in the proportion of Platygyra corals). Our findings support the assertion that small changes in depth may significantly influence the rate and direction of community change.