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Infectious disease can shape community structure, particularly when pathogens affect foundation species. Seagrasses are foundation species that form meadows along coasts worldwide, controlling sediment deposition and biogeochemical cycling while supporting a diverse community of fish and invertebrates. These plants are hosts to wasting diseases that cause necrotic tissue lesions, which could alter seagrass value as food, habitat and mediators of ecosystem processes. However, such biotic interactions and influences on disease dynamics are still not well understood. We investigated whether a common herbivore affected the development of wasting disease on eelgrass. We measured the severity and prevalence of eelgrass wasting disease in a meadow across two summers through repeated field surveys. We assessed the role of the eelgrass herbivore on disease spread and growth using microcosm and mesocosm experiments. We further explored herbivore feeding preferences in a choice trial, which was paired with chemical analysis of plant tissue and analysed using a structural equation model. While the herbivore facilitates the growth of new disease lesions among isolated leaves, on balance they reduce lesion severity by more than 50% in comparison with no-herbivore controls in field-realistic settings. This was likely because the herbivore strongly prefers to eat diseased rather than healthy tissue, consuming nearly twice as much lesion area in choice trials. This preference arises from pathogen-driven changes in the host plant; lesioned tissue requires less force to penetrate than non-lesioned tissue. Additionally, as lesions increase in size, their polyphenolic concentrations drop, which further increases the magnitude of preference for lesioned tissue. Synthesis: These results suggest that these herbivores could help maintain disease in this system at a high prevalence (by facilitating disease development) but low severity (through preferential consumption), which is consistent with our field observations of nearly 100% prevalence and low severity in a natural bed where herbivore density is high. Describing such multi-species interactions in marine systems will advance our predictions of future disease states, as current understandings focus primarily on how environmental change contributes to pathogen outbreaks.

Species persist through resistance and recovery traits induced by natural stressors. Whether human activities exacerbate or moderate the effects of natural stressors is an open question. Because eelgrass (Zostera marina) creates coastal habitat, its response to natural stressors and human activities is of particular management importance. In this study, traits of intertidal eelgrass were examined across cumulative stressors of emersion and oyster culture, including two culture types: oysters grown directly on sediment (ground culture) or supported by gear above the sediment (off-bottom culture). Summer eelgrass was larger above- and below-ground and branched less than in spring, while density and cover were similar seasonally but declined at higher elevation and in ground culture. Eelgrass traits were divided into those related to resistance (larger above-ground size and below-ground storage) and recovery (increased flowering, branching, and rhizome extension). Resistance traits responded additively to intertidal elevation and oyster culture, with above- and below-ground size reduced in all conditions except that rhizome mass was maintained in ground culture. Smaller above-ground size may confer resistance to emersion stress, as a departure from expectations for other stressors. For resilience traits, flowering increased and internode length declined at higher elevation, whereas these traits did not change in ground culture, and off-bottom culture was associated with shorter internodes (additive cumulative stressor) and tended to moderate the enhanced flowering at higher elevations (non-additive, P=0.058). Transitory disturbance in ground culture may reduce eelgrass density with few effects on resilience, whereas off-bottom culture involves longer-term gear placement and trait responses by eelgrass. [ABSTRACT FROM AUTHOR]

A major challenge in biodiversity research is the incorporation of species interactions into frameworks describing population and community response to global edfnmental change (GEC). Mutualisms are a type of species interaction especially sensitive to changing environmental conditions, and the breakdown of facilitative species interactions could amplify the negative impacts of novel climate regimes on focal species.Here, we investigate how reciprocal interactions between two coastal foundation species, the eastern oyster (Crassostrea virginica) and eelgrass (Zostera marina) shift in sign and magnitude in response to ocean warming (+1.5°C) and acidification (−0.4 pH) via a manipulative co‐culture experiment in mesocosms.Under ambient environmental conditions, oysters facilitated eelgrass leaf growth and clonal reproduction by 35% and 38%, respectively. Simultaneously, eelgrass decreased the oyster condition index (the ratio of tissue to shell biomass) by 35%, indicating greater allocation of energy to shell growth instead of soft tissues at ambient conditions. Varying sensitivities of each species to ocean warming and/or acidification treatments led to complex shifts in species interactions that were trait dependent. As such, community outcomes under future conditions were influenced by species interactions that amplified and mitigated species response to environmental change.Synthesis: Given that species interaction effect sizes were similar in magnitude to effect sizes of warming or pH treatments, our results underscore the need to identify key species and interaction types that strongly influence community response to GEC. Specifically, for macrophyte‐bivalve interactions, understanding how physiological limitations on growth are impacted by environmental heterogeneity and co‐culture will support the successful restoration of natural populations and the rapid expansion of aquaculture. [ABSTRACT FROM AUTHOR]

Seagrass meadows are well-known for their capacity to capture and store blue carbon in sediments. However carbon stocks vary significantly between meadows, spanning more than three orders of magnitude on both local and global scales. Understanding the drivers of seagrass carbon stocks could help improve strategies for incorporating blue carbon into management plans. Here, we measured sediment carbon stocks in eelgrass (Zostera marina) meadows and unvegetated areas along the Norwegian coast, spanning wide gradients in temperature, wave exposure, water depth, salinity, and eelgrass biomass. Carbon stocks were generally higher in eelgrass meadows than in adjacent unvegetated areas, yet they displayed considerable variation (400 − 30 000 g C m−2 at 50 cm sediment depth) even among nearby sites. Overall, the highest carbon stocks were found in deeper, muddier, sheltered meadows near river mouths. These sites likely have the highest input and retention of carbon from different sources. Consequently, they should be prioritized as conservation targets for preserving coastal blue carbon stocks. Despite ever-increasing efforts to quantify seagrass blue carbon globally, high uncertainties still persist, partly due to differing methodologies, processes, and environmental context. Blue carbon stock estimates could be improved through the coordination of standardised mapping and sampling methods. [ABSTRACT FROM AUTHOR]

Background: Microorganisms play pivotal roles in seagrass ecosystems by facilitating material and elemental cycling as well as energy flux. However, our understanding of how seasonal factors and seagrass presence influence the assembly of bacterial communities in seagrass bed sediments is limited. Employing high-throughput sequencing techniques, this study investigates and characterizes bacterial communities in the rhizosphere of eelgrass (Zostera marina) and the bulk sediments across different seasons. The research elucidates information on the significance of seasonal variations and seagrass presence in impacting the microbial communities associated with Zostera marina. Results: The results indicate that seasonal variations have a more significant impact on the bacterial community in seagrass bed sediments than the presence of seagrass. We observed that the assembly of bacterial communities in bulk sediments primarily occurs through stochastic processes. However, the presence of seagrass leading to a transition from stochastic to deterministic processes in bacterial community assembly. This shift further impacts the complexity and stability of the bacterial co-occurrence network. Through LEfSe analysis, different candidate biomarkers were identified in the bacterial communities of rhizosphere sediments in different seasons, indicating that seagrass may possess adaptive capabilities to the environment during different stages of growth and development. Conclusions: Seasonal variations play a significant role in shaping these communities, while seagrass presence influences the assembly processes and stability of the bacterial community. These insights will provide valuable information for the ecological conservation of seagrass beds. [ABSTRACT FROM AUTHOR]

Seagrasses are considered to be globally important for carbon sequestration and they provide a range of ecosystem services. However, they are also known to be vulnerable to various anthropogenic activities, not least bottom contacting fishing gears such as dredging and potting. We set out to test the effects of dredge fishing, in early spring and potting in late summer, in a historically fished but considered "pristine" seagrass meadow on the west coast of Ireland. We found that despite dredging and potting pressures, growth of seagrasses was driven by seasonal changes in light and temperature and that neither fishing activity had any effect on rhizome weight or shoot or blade densities during the growing season. We hypothesize that it is possible for fishing to co‐occur with seagrass if fishing activities are restricted to winter or early spring, before the main seagrass growing season, and/or if particular types of gear, such as the traditional gears described here are used. High levels of dredging and potting had positive increases in the count of both sessile and mobile epifauna suggesting that for mobile species at least, they may take advantage of post‐fishing scavenging opportunities. [ABSTRACT FROM AUTHOR]

With so many studies today on the water quality of the sea, one can hardly comprehend the multitude of topics that arise all over the world. This study provides a few graphic syntheses related to the most frequent words (including their clustering and links), trend topics, the spatial distribution of the researched areas, and the thematic evolution of the research directions over the decades. The most frequent authors' keywords have a 50% similitude between the ocean studies and the studies related to the Mediterranean Sea; these keywords are part of a causal chain that dominates the marine studies on water quality: nutrients → eutrophication → phytoplankton → chlorophyll → seagrass. The most frequent words in the titles and abstracts of the selected papers from the Web of Science are "concentration" and "species"; in the Mediterranean studies, "chlorophyll" and "temperature" are the most frequent. In close connection with water quality, Zostera marina (eelgrass) and Crassotrea virginica (eastern oyster) prevail at the global scale, while Posidonia oceanica (Neptune grass) is relevant in the Mediterranean space. Some of the most studied water bodies are the South China Sea, San Francisco Bay, Chesapeake Bay, and, in the Mediterranean Sea, the Adriatic, Ionian, Aegean, and Marmara seas. "Climate change" and "remote sensing" are trend topics that shape the current studies on water quality; the increasing sea surface temperature enhances algal blooms—these need to be monitored using satellite imagery for the sustainable evolution of human activities, including aquaculture. [ABSTRACT FROM AUTHOR]

The aim of study is to determine which environmental factors could influence the biological traits of Z. caespitosa, a unique tuft-forming seagrass. This study examined the dynamics of tufts and the growth of Z. caespitosa, along with the environmental factors. The reproductive traits were also examined to estimate the potential importance of sexual reproduction in population persistence. The density of tufts remained constant, and no new tufts produced through seedling recruitment were observed throughout the sampling period. On the other hand, the tuft size and growth exhibited clear seasonal manners and strong correlations with the water temperature, indicating that water temperature regulates the tuft dynamics and growth. The optimal growth temperature for Z. caespitosa at the study site was approximately ~22.5 °C during early summer, with growth severely inhibited during periods of high-water temperatures. Z. caespitosa was characterized by a low flowering percentage and fewer inflorescences, resulting in extremely low potential seed production. Z. caespitosa maintained its populations through clonal tuft growth with low sexual reproduction and restricted growth at high water temperatures. Hence, this seagrass species may be vulnerable to disturbances, exhibiting low resilience and facing a high risk of becoming a threatened species in coastal waters. [ABSTRACT FROM AUTHOR]

This study investigates the biomass production and growth strategies of the relict seagrass Zostera marina, a species sensitive to high temperatures, within the Venice Lagoon (Italy). Monthly data collected from January to December 2019 and November 2020 to October 2021 in a single station in proximity of one lagoon port-entrance, along with seasonal data from 2018 and 2021 for the whole lagoon, were analyzed in conjunction with environmental parameters and macroalgal presence. The objective was to understand the impact of climate changes, particularly rising water temperatures, on the cover, standing crop and net primary production of Z. marina and the effect of the MoSE gate closures designed to protect Venice from high-water events. Despite expectations of a decline due to temperature increase and reduced water exchange, our findings reveal a notable adaptability of Z. marina, with increases in both cover and biomass. This resilience suggests that Z. marina can counteract environmental challenges, making this study relevant for broader ecological and conservation contexts beyond the Venice Lagoon. [ABSTRACT FROM AUTHOR]

ttarakhand has a rich plant biodiversity, many of which have high medicinal properties. Medicinal plants have been used against insects, diseases, and herbivorous mammals through the production of chemical compounds. Various reasons like overexploitation, overgrazing, unsustainable development, etc. lead to their extinction and make them threatened species. The International Union for Conservation of Nature (IUCN) was established to prioritize species conservation, assess threat status, and develop suitable strategies due to the vast diversity of species. The genetic diversity of these threatened species can be determined using various markers. Molecular marker technology aids in analyzing genetic diversity, population structure, and species adaptation, enabling conservation measures and assessing genetic stability in conserved species. In this article, we have reviewed the genetic diversity of six threatened plants of Uttarakhand (Picrorhiza kurroa, Aconitum heterophyllum, Nardostachys jatamansi, Dactylorhiza hatagirea, Zanthoxylum armatum, Saussurea costus) in India as well as in other countries. A review highlighting the use of recent molecular markers like ISSR, SSR, RAPD, etc. to determine genetic diversity. Most of the medicinal plants show diversity less than 0.5, which indicates that the plants are at extreme risk of extinction. The diversity is calculated based on polymorphism percentage. The analysis of genetic diversity between species using ISSR, nextgeneration sequencing, AFLP, and microsatellite markers reveals low genetic diversity in A. heterophyllum, P. kurroa, N. jatamansi, Z. armatum, D. hatagirea, and S. costus. [ABSTRACT FROM AUTHOR]

Foundational habitats such as seagrasses and coral reefs are at severe risk globally from climate warming. Infectious disease associated with warming events is both a cause of decline and an indicator of stress in both habitats. Since new approaches are needed to detect refugia and design climate-smart networks of marine protected areas, we test the hypothesis that the health of eelgrass (Zostera marina) in temperate ecosystems can serve as a proxy indicative of higher resilience and help pinpoint refugia. Eelgrass meadows worldwide are at risk from environmental stressors, including climate warming and disease. Disease outbreaks of Labyrinthula zosterae are associated with recent, widespread declines in eelgrass meadows throughout the San Juan Islands, Washington, USA. Machine language learning, drone surveys, and molecular diagnostics reveal climate impacts on seagrass wasting disease prevalence (proportion of infected individuals) and severity (proportion of infected leaf area) from San Diego, California, to Alaska. Given that warmer temperatures favor many pathogens such as L. zosterae , we hypothesize that absent or low disease severity in meadows could indicate eelgrass resilience to climate and pathogenic stressors. Regional surveys showed the San Juan Islands as a hotspot for both high disease prevalence and severity, and surveys throughout the Northeast Pacific indicated higher prevalence and severity in intertidal, rather than subtidal, meadows. Further, among sites with eelgrass declines, losses were more pronounced at sites with shallower eelgrass meadows. We suggest that deeper meadows with the lowest disease severity will be refuges from future warming and pathogenic stressors in the Northeast Pacific. Disease monitoring may be a useful conservation approach for marine foundation species, as low or absent disease severity can pinpoint resilient refugia that should be prioritized for future conservation efforts. Even in declining or at-risk habitats, disease surveys can help identify meadows that may contain especially resilient individuals for future restoration efforts. Our approach of using disease as a pulse point for eelgrass resilience to multiple stressors could be applied to other habitats such as coral reefs to inform conservation and management decisions. [ABSTRACT FROM AUTHOR]

Dwarf eelgrass, Zostera noltii, is an important ecosystem engineer that creates dense meadows along the coasts of Europe and Northwest Africa. During the last century, this seagrass species suffered severe population declines, and to counteract these losses, restoration has emerged as an important management tool. Thus far, restoration efforts with Z. noltii have only been performed with shoot‐ and core‐based methods, which are challenging to upscale sustainably.Here, we explored if Z. noltii can be restored with seeds, thus potentially offering an upscalable solution for future restoration efforts. With the newly developed dispenser injection seeding (DIS) method, we tried seed‐based Z. noltii restoration in the intertidal Wadden Sea. With a field experiment, we investigated how seeding depth (1.5 and 3 cm) and seed amount (5, 10 and 20 seeds/injection) affected Z. noltii recruitment success and efficiency.Most importantly, our results show that Z. noltii can be restored with seeds, as 3 months after seeding, 184 individual patches had emerged from our 7000 seeds (2.6% recruitment). Recruitment success (number of restored patches/plot) was enhanced by higher seed amounts (20 > 5 seeds/injection), while the opposite was true for recruitment efficiency (number of restored patches/seed), which was reduced by higher seed amounts (20 < 5 seeds/injection). Restored Z. noltii survived the first winter in all experimental plots, but seagrass cover (square metre/plot) reduced in two‐thirds of the plots compared to the first growing season.In conclusion, our findings show the potential of seed‐based Z. noltii restoration and provide insights on how upscaling of restoration efforts for this species can be performed more efficiently and sustainably in the future. [ABSTRACT FROM AUTHOR]

Enhalus acoroides (L.f.) Royle is a large and important foundation seagrass species in the tropical Indo-Pacific. The northern marginal populations in China have been declining over the last decades. The reproductive phenology and fruit set of this dioecious seagrass were investigated from June 2017 to February 2018 in two areas in Li'an lagoon, Hainan Island, China. We found that E. acoroides flowered year-round. However, the flowering intensity varied among seasons and was highest in the summer and lowest in the winter. The shoot sex ratio was male-biased, and the pollen-ovule ratio was approximately 104: 1, based on the sex ratio and the number of male florets per inflorescence. Female and male plants flowered at the same time in this population. Despite the high reproductive investment in terms of flower formation observed throughout the year, the abundance of the mature fruits was low, possibly due to physical disturbance and cover by epiphyte and algae. This study provides insight into the reproductive ecology of E. acoroides, which will be useful for the future conservation of this threatened seagrass. [ABSTRACT FROM AUTHOR]

Microplastics are fast-emerging as another potential threat to already globally declining seagrass ecosystems, but there is a paucity of in situ surveys showing their accumulations. Here, we surveyed multiple Zostera marina L. meadows in 2020 and 2021 across Massachusetts, USA, for microplastic contamination, as well as identified factors related to patterns of accumulation. We found that microplastics were ubiquitous throughout all sites regardless of proximity to human development, with fibers being the most common microplastic type. In addition, we showed that accumulation of microplastics within seagrass meadows was related to epiphytic cover on leaves, plant morphology, and bulk-density in sediments. The results of this study provide the first in situ baseline microplastic concentrations on Z. marina plants and sediments for the temperate western North Atlantic. Additionally, we identify specific biotic and abiotic factors related to patterns of microplastic accumulation in these ecosystems. [ABSTRACT FROM AUTHOR]

Abstract Seagrass meadows are well-known for their capacity to capture and store blue carbon in sediments. However carbon stocks vary significantly between meadows, spanning more than three orders of magnitude on both local and global scales. Understanding the drivers of seagrass carbon stocks could help improve strategies for incorporating blue carbon into management plans. Here, we measured sediment carbon stocks in eelgrass (Zostera marina) meadows and unvegetated areas along the Norwegian coast, spanning wide gradients in temperature, wave exposure, water depth, salinity, and eelgrass biomass. Carbon stocks were generally higher in eelgrass meadows than in adjacent unvegetated areas, yet they displayed considerable variation (400 − 30 000 g C m−2 at 50 cm sediment depth) even among nearby sites. Overall, the highest carbon stocks were found in deeper, muddier, sheltered meadows near river mouths. These sites likely have the highest input and retention of carbon from different sources. Consequently, they should be prioritized as conservation targets for preserving coastal blue carbon stocks. Despite ever-increasing efforts to quantify seagrass blue carbon globally, high uncertainties still persist, partly due to differing methodologies, processes, and environmental context. Blue carbon stock estimates could be improved through the coordination of standardised mapping and sampling methods.

Zostera marina is an ecologically valuable species that has been declining due to anthropogenic environmental stressors. In this study, spatial and temporal indicators of eelgrass stress, such as coverage and biomass, were compared with the isotopic composition of C, N, and S to understand the mechanism(s) of plant stress. Eelgrass samples were collected in June, July, and August of 2020 at five stations along an estuary spatial gradient in the southern Gulf of St. Lawrence to measure above- and below-ground biomass and tissue isotopes in eelgrass leaves and roots/rhizomes. Eelgrass biomass was lowest at the innermost sampling station, which coincided with eutrophication-induced hypoxia relative to outer sampling stations. δ13C levels at the upstream station were depleted compared to downstream stations. Comparatively, δ15N and δ34S findings were not correlated with plant biomass. Thus, sulfide intrusion was not a major stressor for eelgrass in this estuary. Between the years 2014 and 2020, eelgrass coverage was found to have increased, which coincided with high and low recorded external nutrient loads from the Wheatley River, respectively. Ultimately, these findings indicate that isotopic composition and biomass can be useful in assessing the health of eelgrass in temperate estuaries.

Seagrasses are marine angiosperms that form highly productive and diverse ecosystems. These ecosystems, however, are declining worldwide. Plant-associated microbes affect critical functions like nutrient uptake and pathogen resistance, which has led to an interest in the seagrass microbiome. However, despite their significant role in plant ecology, viruses have only recently garnered attention in seagrass species. In this study, we produced original data and mined publicly available transcriptomes to advance our understanding of RNA viral diversity in Zostera marina, Zostera muelleri, Zostera japonica, and Cymodocea nodosa. In Z. marina, we present evidence for additional Zostera marina amalgavirus 1 and 2 genotypes, and a complete genome for an alphaendornavirus previously evidenced by an RNA-dependent RNA polymerase gene fragment. In Z. muelleri, we present evidence for a second complete alphaendornavirus and near complete furovirus. Both are novel, and, to the best of our knowledge, this marks the first report of a furovirus infection naturally occurring outside of cereal grasses. In Z. japonica, we discovered genome fragments that belong to a novel strain of cucumber mosaic virus, a prolific pathogen that depends largely on aphid vectoring for host-to-host transmission. Lastly, in C. nodosa, we discovered two contigs that belong to a novel virus in the family Betaflexiviridae. These findings expand our knowledge of viral diversity in seagrasses and provide insight into seagrass viral ecology. [ABSTRACT FROM AUTHOR]

Seagrass meadows play pivotal roles in coastal biochemical cycles, with nitrogen fixation being a well-established process associated with living seagrass. Here, we tested the hypothesis that nitrogen fixation is also associated with seagrass debris in Danish coastal waters. We conducted a 52-day in situ experiment to investigate nitrogen fixation (proxied by acetylene reduction) and dynamics of the microbial community (16S rRNA gene amplicon sequencing) and the nitrogen fixing community (nifH DNA/RNA amplicon sequencing) associated with decomposing Zostera marina leaves. The leaves harboured distinct microbial communities, including distinct nitrogen fixers, relative to the surrounding seawater and sediment throughout the experiment. Nitrogen fixation rates were measurable on most days, but highest on days 3 (dark, 334.8 nmol N g−1 dw h−1) and 15 (light, 194.6 nmol N g−1 dw h−1). Nitrogen fixation rates were not correlated with the concentration of inorganic nutrients in the surrounding seawater or with carbon:nitrogen ratios in the leaves. The composition of nitrogen fixers shifted from cyanobacterial Sphaerospermopsis to heterotrophic genera like Desulfopila over the decomposition period. On the days with highest fixation, nifH RNA gene transcripts were mainly accounted for by cyanobacteria, in particular by Sphaerospermopsis and an unknown taxon (order Nostocales), alongside Proteobacteria. Our study shows that seagrass debris in temperate coastal waters harbours substantial nitrogen fixation carried out by cyanobacteria and heterotrophic bacteria that are distinct relative to the surrounding seawater and sediments. This suggests that seagrass debris constitutes a selective environment where degradation is affected by the import of nitrogen via nitrogen fixation. [ABSTRACT FROM AUTHOR]

Eelgrass, Zostera marina L., is vital to marine ecosystems, providing habitat, filtering pollutants, improving water quality, and serving as a source of bioactive compounds for pharmaceuticals. This study aimed to isolate and identify phenolic compounds from Z. marina, biotransform the main metabolite, rosmarinic acid (RA), and evaluate the anti-tyrosinase activity of these compounds. Various chromatographic techniques were employed to isolate compounds from Z. marina (1-4). Compound 1, exhibiting broad pharmaceutical activity, was biotransformed by Deinococcus geothermalis amylosucrase (DgAS) into two new glycosylated products (5-6). The isolated and biotransformed compounds were tested for anti-tyrosinase activity using a mushroom tyrosinase assay. Molecular docking and quantum chemical calculations were conducted to clarify the binding mode and reactivity of the compounds. The isolated compounds were identified via NMR and HR-MS as rosmarinic acid (RA) 1, methyl rosmarinate 2, methyl isorinate 3, and pinoresinol 4′-O-β-D-glucopyranoside 4. This is the first report of isolating and identifying compounds (2-4) from the Zosteraceae family. The glycosylated compounds were identified as rosmarinic acid 4-O-α-D-glucopyranoside 5 and rosmarinic acid 3′-O-α-D-glucopyranoside 6. Among all compounds, (4-6) showed significant tyrosinase inhibition, with rates of 55.5%, 22.3%, and 30.8%, respectively, compared to arbutin. The two glycosylated products exhibited better anti-tyrosinase activity than 1. In silico results aligned with in vitro findings. This study highlights Z. marina's potential as a source of polyphenolic compounds with significant anti-aging activity, emphasizing the discovery of new anti-aging ingredients to enhance quality of life. [ABSTRACT FROM AUTHOR]

The eastern coastline of James Bay is known to have been home to sizeable eelgrass beds (Zostera marina L.) which thrived in the bay's shallow, subarctic waters. The region was subjected to substantial hydroelectric dams, large fires, and other human activities in the past half-century. To assess the impact of these factors on eelgrass beds, a historical reconstruction of eelgrass bed distribution was performed from images acquired by Landsat-5 Thematic Mapper (TM) in 1988, 1991, and 1996 and images of the Landsat-8 Operational Land Imager (OLI) in 2019. All the images were classified using the Random Forests classifier (RF) and assessed for accuracy each year on a bay-wide scale using an independent field validation dataset. The validation data were extracted from an eelgrass bed map established using aerial photos and field surveys in 1986, 1991, and 1995 and from a field survey in 2019. The overall validation accuracy of the classified images (between 72% and 85%) showed good agreement with the other datasets for most locations, providing reassurance about the reliability of the research. This makes it possible to use satellite imagery to detect past changes to eelgrass distribution within a bay. The classified images of 1988 and 1996 were also compared to aerial photos taken in years close to each other at ten sites to determine their ability to assess small eelgrass beds' shape and presence. Such a comparison revealed that the classified images accurately portrayed eelgrass distribution even at finer scales. [ABSTRACT FROM AUTHOR]

Seagrass recovery has been reported across the globe where previously eutrophied waters have become less nutrient‐rich. In the European Wadden Sea, different recovery trajectories were found after riverine nutrient loads decreased, namely full, temporary and no recovery. We compiled intertidal seagrass presence (Zostera noltei and Z. marina) and eutrophication data for 1930–2020, to relate the seagrass trajectories and regional eutrophication differences to riverine nutrient loads, and inferred prospects for seagrass recovery.Seagrass fully recovered in the less eutrophic North Frisian region. The recovery trajectory was tightly coupled to riverine nutrient load reduction. Relative seagrass area (meadow area/region area) dropped from 10% prior to eutrophication to 2% during the eutrophication peak, increased to 7% during the nutrient reduction period and subsequently expanded to 13%. Colonization of marginal habitats was observed, indicating propagule spillover from neighbouring meadows.The more eutrophic southern regions showed no or only temporary seagrass recovery. Prospects for (limited) recovery are good in only two out of four southern regions, provided that riverine nutrient loads are further reduced by ~40% (reference: 2010–2017). Without this reduction, seagrasses may only temporarily recover and will remain vulnerable to erratic disturbances like macroalgae accumulation or storms.Historical evidence and application of habitat suitability models suggest that the potential relative seagrass area in the southern regions is low: less than 0.2% in the western Dutch region and maximum 2.4% in the Ems‐Jade region.Synthesis and applications. Within a large seascape (15,000 km2) the least eutrophicated region showed seagrass recovery upon nutrient reduction. We translated the critical riverine nutrient loads for this recovery, via regional eutrophication indicators, to loads that may enable a sustained recovery in the other regions. This technique is applicable in other complex systems, provided sufficient historical data are available. Propagule spillover exerts a positive feedback at metapopulation scale leading to acceleration of recovery. Occupied and potential seagrass habitat (e.g. assessed by the maximum recorded area in the past) are thus important landscape selection criteria for restoration, particularly when eutrophication is not yet sufficiently reduced. [ABSTRACT FROM AUTHOR]

The fish species diversity, fish density, and distribution in the nearshore beds of Zostera marina and Ulva fenestrata have been assessed by SCUBA visual counts in May–September and November 2021. In total, 23 fish species have been registered. The fish species richness increases from 8–13 species in May to a maximum of 17–19 species at the end of June. Then it slightly decreases in July–September and reaches its lowest values in November (2–5 species). The same changes have been noted for the fish density. Fish diversity in the Zostera beds is higher than in the Ulva ones. The similarity of the fish species composition between Zostera and Ulva is low (the Sørensen-Czekanowski index varied from 0.32 to 0.44). In general, fish density is low (from 2.4 to 112.4 ind./50 m2 in Ulva (in November) and Zostera (in July) beds, respectively), although with an exception for Opisthocentrus spp. and Gymnogobius heptacanthus juveniles. An abnormal high bottom water temperature (above 26°C) in late July–early August has led to temporal avoidance of shallow water with plant beds by fishes (except for Gymnogobius heptacanthus) and their shift to a depth of 3.5–4.5 m, where the temperature was lower by 4.0–5.7°С. [ABSTRACT FROM AUTHOR]

Worldwide seagrass habitats are under severe anthropogenic threat. In the United Kingdom (UK), the health of habitats of the widely distributed Zostera species is particularly threatened by eutrophication that can lead to detrimental macroalgae overgrowth. To manage and conserve seagrass habitats, effective monitoring tools are required.We use an off‐the‐shelf consumer‐grade multispectral (RGB, red edge, and near‐infrared) camera mounted on an unoccupied aerial vehicle (UAV) to map an intertidal multispecies seagrass environment in Lindisfarne National Nature Reserve, Northumberland, UK.Field surveys were undertaken of three seagrass areas, including those dominated by Zostera noltii, Zostera marina and macroalgae. Using the Maximum Likelihood Classifier (MLC), results indicated an overall accuracy (OA) between 84% and 91% across classified habitat maps. As expected, the red edge and near‐infrared bands offered an advantage beyond RGB imagery to discriminate between the vegetation types for accurate habitat mapping.Our research provides a foundation for accurately mapping a complex intertidal seagrass environment through the utilisation of an off‐the‐shelf multispectral UAV. The study may aid the implementation and development of effective monitoring programmes for the management of Zostera spp. decline and macroalgae proliferation to prevent seagrass degradation and conserve these valuable yet fragile ecosystems. [ABSTRACT FROM AUTHOR]

Background: Melon fruit fly, Zeugodacus cucurbitae Coquillett (Diptera: Tephritidae), is a devastating polyphagous pest attacking large number of fruits and vegetables causing huge economic yield losses across the world. Management of this notorious pest is very challenging as the larvae feed inside the fruit. Hence, the present research study aimed to screen the indigenous Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) strains causing toxicity to larvae and to identify the insecticidal toxicity-related genes present in respective strains. In the present study, 50 indigenous B. thuringiensis (Bt) strains along with one reference strain were screened against second-instar larvae Z. cucurbitae. All the strains were analyzed for presence of 21 dipteran active cry genes. Results: Mortality in Z. cucurbitae larvae due to Bt strains ranged from 16 to 92%. PCR results revealed that each strain tested positive for a minimum of three cry genes to maximum of nine cry genes. Among the cry genes, cry1A, cry2A, cry1C, cry19, cry11 and cry70 were detected in high frequency of 100, 88, 84, 74, 58 and 54%, respectively. Bioassay studies revealed that ten out of fifty strains displayed more than 50% mortality. Hence, these ten strains, along with the reference strain, were further tested for mortality for the calculation of the median lethal concentration (LC50). The LC50 values ranged between 38.48 and 105.18 μg/ml. The lowest LC50 found for the strain NBAIR Bt107 was 38.48 μg/ml and was on par with the reference strain (Bti 4Q1) (31.3 μg/ml). Conclusion: Indigenous Bt strains displayed a toxicity against the larvae of Z. cucurbitae. The probable dipteran active cry genes responsible for toxicity were interpreted. Thus, the Cry toxins from Bt can play a very important role in the management of Z. cucurbitae. [ABSTRACT FROM AUTHOR]

Water temperature is an important environmental factor for many ecological processes in coastal ecosystems. Here, we study water temperature dynamics at a set of study sites on the Atlantic coast of Nova Scotia where eelgrass beds are found. The central emphasis is to predict temperature on scales relevant to coastal ecosystem processes using a high-resolution nearshore oceanographic model based on the Finite Volume Community Ocean Model (FVCOM). The model predictions were evaluated against observed temperature time series at six sites for three years from 2017-2019; the evaluation indicates that the model was able to replicate the temperature variation on time scales from hours to seasonal. We also used various biologically tailored temperature metrics relevant to eelgrass condition, including mean seasonal values and variability, daily ranges, growing degree day (GDD), and warm events, to validate the model against time series observations to better understand the temperature regime at the study sites. Frequency resolved Willmott skill scores were >0.7, and the temperature metrics were well predicted with the exception of a bias in GDD at some of the shallow sites. The eelgrass sites have a wide range of temperature conditions. Mean water temperature in the summer differed by more than 7°C between the shallowest and the deepest sites, and the rate of heat accumulation was fastest at shallow sites which had ≥ 12 extreme warm events per year. While the amplitude of the temperature variations within the high frequency band (<48 hr) was greater in shallower sites, temperature changes on meteorological time scales (48 hr to 60 days) were coherent at all sites, suggesting the importance of coast-wide processes. The results of this study demonstrated that our high resolution numerical model captured biologically relevant temperature dynamics at different time scales and over a large spatial region, and yet still accurately predicted detailed temperature dynamics at specific nearshore sites. Thus, the model can provide important insights into coastal temperature dynamics that are potentially useful for conservation planning and understanding the implications of future change. [ABSTRACT FROM AUTHOR]

Among the several threats to humanity by anthropogenic activities, contamination of the environment by heavy metals is of great concern. Upon entry into the food chain, these metals cause serious hazards to plants and other organisms including humans. Use of microbes for bioremediation of the soil and stress mitigation in plants are among the preferred strategies to provide an efficient, cost-effective, eco-friendly solution of the problem. The current investigation is an attempt in this direction where fungal strain PH1 was isolated from the rhizosphere of Parthenium hysterophorus which was identified as Aspergillus niger by sequence homology of the ITS 1 and ITS 4 regions of the rRNA. The strain was tested for its effect on growth and biochemical parameters as reflection of its potential to mitigate Pb stress in Zea mays exposed to 100, 200 and 500 µg of Pb/g of soil. In the initial screening, it was revealed that the strain has the ability to tolerate lead stress, solubilize insoluble phosphate and produce plant growth promoting hormones (IAA and SA) and other metabolites like phenolics, flavonoids, sugar, protein and lipids. Under 500 µg of Pb/g of soil, Z. mays exhibited significant growth retardation with a reduction of 31% in root length, 30.5% in shoot length, 57.5% in fresh weight and 45.2% in dry weight as compared to control plants. Inoculation of A. niger to Pb treated plants not only restored root and shoot length, rather promoted it to a level significantly higher than the control plants. Association of the strain modulated the physio-hormonal attributes of maize plants that resulted in their better growth which indicated a state of low stress. Additionally, the strain boosted the antioxidant defence system of the maize there by causing a significant reduction in the ascorbic acid peroxidase (1.5%), catalase (19%) and 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical scavenging activity (33.3%), indicating a lower stress condition as compared to their non-inoculated stressed plants. Based on current evidence, this strain can potentially be used as a biofertilizer for Pb-contaminated sites where it will improve overall plant health with the hope of achieving better biological and agricultural yields. [ABSTRACT FROM AUTHOR]

Coastal vegetated ecosystems including mangroves, seagrasses, and salt marshes are often shaped by positive plant–environment feedbacks. Plants improve their own living conditions with increasing patch size and density by attenuating hydrodynamics and stabilizing sediments. As these habitat modifications are critical for survival and growth, the positive density‐dependent nature of these feedbacks can lead to establishment thresholds for young plants in absence of mature conspecifics. Although feedback strength is known to depend on hydrodynamic exposure and plant traits (e.g. stiff versus flexible stems), it remains unclear how 1) opposing morphological plant traits affect establishment in contrasting environments, and 2) whether trait plasticity influences establishment success. Here, we investigate this by transplanting two tidal species with opposing growing strategies – Spartina anglica forms tussocks of stiff stems while Zostera noltii forms patches of stress‐avoiding flexible shoots – from two different donor sites in eight experimental locations. Results show that the survival and growth of both species was most successful at field locations with diverging environmental characteristics, while overall survival was highest for Z. noltii. Mainly, S. anglica survival was highest at locations with high organic matter and silt content and higher elevation relative to the tidal amplitude. In contrast, Z. noltii survival was highest at locations with larger grainsize and lower relative elevations. Furthermore, despite initial differences in plant traits between the two donor sites of Z. noltii, we found no effects of donor origin. Contrastingly, we found a significant effect of donor origin on S. anglica growth, even though transplants from the two donor sites showed no initial trait differences. Collectively, these results suggest that the stress‐tolerance strategy of S. anglica hampers establishment in exposed conditions, whereas the stress‐avoiding Z. noltii appears to be more susceptible to stress from desiccation and silty sediments. [ABSTRACT FROM AUTHOR]

Access to high‐quality food is critical for long‐distance migrants to provide energy for migration and arrival at breeding grounds in good condition. We studied effects of changing abundance and availability of a marine food, common eelgrass (Zostera marina L.), on an arctic‐breeding, migratory goose, black brant (Brant bernicla nigricans Lawrence 1846), at a key non‐breeding site, Bahía San Quintín, Mexico. Eelgrass, the primary food of brant, is consumed when exposed by the tide or within reach from the water's surface. Using an individual‐based model, we predicted effects of observed changes (1991–2013) in parameters influencing food abundance and availability: eelgrass biomass (abundance), eelgrass shoot length (availability, as longer shoots more within reach), brant population size (availability, as competition greater with more birds), and sea level (availability, as less food within reach when sea level higher). The model predicted that the ability to gain enough energy to migrate was most strongly influenced by eelgrass biomass (threshold January biomass for migration = 60 g m−2 dry mass). Conversely, annual variation in population size (except for 1998), was relatively low, and variation in eelgrass shoot length and sea level were not strongly related to ability to migrate. We used observed data on brant body mass at Bahía San Quintín and annual survival to test for effects of eelgrass biomass in the real system. The lowest observed values of body mass and survival were in years when biomass was below 60 g m−2, although in some years of low biomass body mass and/or survival was higher. This suggests that the real birds may have some capacity to compensate to meet their energy demands when eelgrass biomass is low. We discuss consequences for brant population trends and conservation. [ABSTRACT FROM AUTHOR]

Studies of community assembly typically focus on the effects of abiotic environmental filters and stabilizing competition on functional trait dispersion within single trophic levels. Predation is a well‐known driver of community diversity and composition, yet the role of functionally diverse predator communities in filtering prey community traits has received less attention. We examined functionally diverse communities of predators (fishes) and prey (epifaunal crustaceans) in eelgrass (Zostera marina) beds in two northern California estuaries to evaluate the filtering effects of predator traits on community assembly and how filters acting on predators influence their ability to mediate prey community assembly. Fish traits related to bottom orientation were correlated with more clustered epifauna communities, and epifauna were generally overdispersed while fishes were clustered, suggesting prey may be pushed to disparate areas of trait space to avoid capture by benthic sit‐and‐wait predators. We also found correlations between the trait dispersions of predator and prey communities that strengthened after accounting for the effects of habitat filters on predator dispersion, suggesting that habitat filtering effects on predator species pools may hinder their ability to affect prey community assembly. Our results present compelling observational evidence that specific predator traits have measurable impacts on the community assembly of prey, inviting experimental tests of predator trait means on community assembly and explicit comparisons of how the relative effects of habitat filters and intraguild competition on predators impact their ability to affect prey community assembly. Integrating our understanding of traits at multiple trophic levels can help us better predict the impacts of community composition on food web dynamics as regional species pools shift with climate change and anthropogenic introductions. [ABSTRACT FROM AUTHOR]

Zieria buxijugum , Z. formosa , and Z. parrisiae are three closely related, Critically Endangered species of questionable taxonomic validity that occur within six kilometres of each other on the south coast of New South Wales, Australia. We investigated genetic relationships and diversity of these species, along with two related but taxonomically distinct congeners, Z. granulata and Z. tuberculata , and a possible undescribed taxon, Z. aff. tuberculata. Double-digest restriction-site associated sequencing (ddRADseq) was used to generate anonymous genomic loci that were used for phylogenetic, network, and genetic structure analyses, and for estimating genetic diversity of the threatened species. Our results support the current taxonomic status of Z. buxijugum , Z. formosa , and Z. parrisiae , and suggest that Z. aff. tuberculata warrants recognition as a distinct species. We detected no evidence of inbreeding in the three Critically Endangered species, and found their genetic diversity to be similar to that of the more widespread species Z. granulata and Z. tuberculata. Comparison of plant material held in ex situ collections at the Australian National Botanic Gardens with wild plants highlighted several genotypes of the Critically Endangered species that are not represented in the ex situ collection, and we provide suggestions for the future inclusion of those unrepresented genotypes. [ABSTRACT FROM AUTHOR]

Non-structural carbohydrates (NSCs) are energetic compounds that can be accumulated in tissues and mobilized during periods of unfavorable conditions to maintain the biological functions of plants. The balance of these biochemical compounds is controlled by environmental factors such as temperature and irradiance. Zostera noltei and Zostera marina find one of their southern distribution limits in southern Spain, where relatively high seawater temperatures are reached during summer (23–24 °C). To better understand the effects of elevated temperatures on the concentration of NSCs, we conducted a seasonal study at Cadiz Bay, representing warm-adapted populations of these species. Our results showed a bimodal pattern in both species, with the highest NSC content observed in December and June, followed by a depletion in March and August. In addition, the NSC content observed in the leaves of Z. noltei (71.26 ± 30.77 mg g−1 dry weight) was higher than in the rhizomes and roots (52.14 ± 38.86 mg g−1 DW). The observed patterns suggest that these species accumulated NSCs to cope with periods of unfavorable environmental conditions. We also suggest that the limited concentration of NSCs in Z. noltei rhizomes and roots indicates that this population may be suffering physiological stress. [ABSTRACT FROM AUTHOR]

Net global losses of seagrasses have accelerated efforts to understand recovery from disturbances. Stressors causing disturbances (e.g., storms, heatwaves, boating) vary temporally and spatially within meadows potentially affecting recovery. To test differential recovery, we conducted a removal experiment at sites that differed in thermal stress for a temperate seagrass (Zostera marina). We also synthesized prior studies of seagrass recovery to assess general patterns. Seagrass shoots were removed from 28.3 m2 plots at edge and central sites of a meadow in South Bay, Virginia, USA. We hypothesized faster recovery for edge plots where greater oceanic exchange reduces thermal stress. Contrary to our hypothesis recovery was most rapid in the central meadow matching control site shoot density in 24 months. Recovery was incomplete at the meadow edge and estimated to require 158 months. Differences in recovery were likely due to storm‐driven sediment erosion at the edge sites. Based on data from prior recovery studies, which were primarily on monospecific meadows of Zostera, seagrasses recover across a broad range of conditions with a positive, nonlinear relationship between disturbance area and recovery time. Our experiment indicates position within a seagrass meadow affects disturbance susceptibility and length of recovery. Linking this finding to our literature synthesis suggests increased attention to spatial context will contribute to better understanding variation in recovery rates. [ABSTRACT FROM AUTHOR]

Ten new decalin polyketides, zosteropenilline M (1), 11-epi-8-hydroxyzosteropenilline M (2), zosteropenilline N (3), 8-hydroxyzosteropenilline G (4), zosteropenilline O (5), zosteropenilline P (6), zosteropenilline Q (7), 13-dehydroxypallidopenilline A (8), zosteropenilline R (9) and zosteropenilline S (10), together with known zosteropenillines G (11) and J (12), pallidopenilline A (13) and 1-acetylpallidopenilline A (14), were isolated from the ethyl acetate extract of the fungus Penicillium yezoense KMM 4679 associated with the seagrass Zostera marina. The structures of isolated compounds were established based on spectroscopic methods. The absolute configurations of zosteropenilline Q (7) and zosteropenilline S (10) were determined using a combination of the modified Mosher's method and ROESY data. The absolute configurations of zosteropenilline M (1) and zosteropenilline N (3) were determined using time-dependent density functional theory (TD-DFT) calculations of the ECD spectra. A biogenetic pathway for compounds 1–14 is proposed. The antimicrobial, cytotoxic and cytoprotective activities of the isolated compounds were also studied. The significant cytoprotective effects of the new zosteropenilline M and zosteropenillines O and R were found in a cobalt chloride (II) mimic in in vitro hypoxia in HEK-293 cells. 1-Acetylpallidopenilline A (14) exhibited high inhibition of human breast cancer MCF-7 cell colony formation with IC50 of 0.66 µM and its anticancer effect was reduced when MCF-7 cells were pretreated with 4-hydroxitamoxifen. Thus, we propose 1-acetylpallidopenilline A as a new xenoestrogen with significant activity against breast cancer. [ABSTRACT FROM AUTHOR]

Plant cells harbor two membrane-bound organelles containing their own genetic material—plastids and mitochondria. Although the two organelles coexist and coevolve within the same plant cells, they differ in genome copy number, intracellular organization, and mode of segregation. How these attributes affect the time to fixation or, conversely, loss of neutral alleles is currently unresolved. Here, we show that mitochondria and plastids share the same mutation rate, yet plastid alleles remain in a heteroplasmic state significantly longer compared with mitochondrial alleles. By analyzing genetic variants across populations of the marine flowering plant Zostera marina and simulating organelle allele dynamics, we examine the determinants of allele segregation and allele fixation. Our results suggest that the bottlenecks on the cell population, e.g. during branching or seeding, and stratification of the meristematic tissue are important determinants of mitochondrial allele dynamics. Furthermore, we suggest that the prolonged plastid allele dynamics are due to a yet unknown active plastid partition mechanism. The dissimilarity between plastid and mitochondrial novel allele fixation at different levels of organization may manifest in differences in adaptation processes. Our study uncovers fundamental principles of organelle population genetics that are essential for further investigations of long-term evolution and molecular dating of divergence events. [ABSTRACT FROM AUTHOR]

Phragmites australis is a common helophyte, covering much of the sheltered and shallow soft bottoms along the coasts of the Baltic Sea. Despite the expansion of P. australis over the past decades, there is little information on aquatic macroinvertebrates within P. australis beds. In this study, we examined the effect of large-scale (wave exposure, nutrients) and small-scale (distance from the seaward edge, live and dead stalk density, epiphyte and rhizome biomass) drivers on the density, taxa richness, diversity, and community structure of epifauna and infauna in monospecific P. australis beds around the Åland Islands and the Archipelago Sea. We found that higher wave exposure and nutrient levels generally supported higher epi- and infauna abundance and taxa richness. The effects on Shannon–Wiener diversity were less evident apart from an increase of the infauna diversity in the Archipelago Sea with increasing nutrient levels. On a local scale, the distance from the seaward edge, live and dead stalk density, and epiphyte biomass had varying effects on both epi- and infauna communities in the different regions. Rhizome biomass had no effect on either the epi- or infauna abundance, taxa richness, or diversity. Furthermore, according to existing studies, other habitats, e.g., Zostera marina meadows, Fucus vesiculosus belts, and vegetated soft-bottomed shallow bays, are generally characterized by more abundant fauna, except for the infauna, which had a higher density in P. australis beds than in vegetated soft-bottomed shallow bays. P. australis are a widespread, expanding, and understudied habitat with an important role in supporting coastal biodiversity. [ABSTRACT FROM AUTHOR]

Seagrass meadows are known as hot spots for carbon accumulation, but there is limited field data on the variability of sediment accumulation across time and space. We developed a method to assess spatial and temporal heterogeneity in net sediment accumulation in seagrass meadows using small, inexpensive samplers, allowing for over 200 unique measurements across multiple transects within our study site. Using this method, we assessed sediment accumulation across seagrass meadow edges, and in varying weather conditions. We found the greatest accumulation of sediment 5 m outside of seagrass meadow edges, with sediment accumulation rates averaging just under 100 g m−2 day−1, though rates were highly variable. Carbon accumulation from settled sediment was generally greater outside of seagrass meadow edges than within the bed, especially at sites undergoing recent expansion. Measurements made during tropical storms showed both scouring of sediment away from sites, and increased accumulation, depending on site properties as well as individual tropical storm characteristics. In the storm that had a measurable storm surge, scouring of sediment was a more dominant mechanism, whereas deposition dominated in the storm that had high winds but no associated storm surge. Our data demonstrate the necessity of including measurements that characterize both spatial and meteorological variability to develop a more holistic understanding of the movement of sediment and particulate organic carbon associated with seagrass meadows, especially as meadow area becomes increasingly fragmented with human activity and global change. [ABSTRACT FROM AUTHOR]

UK recreational boating infrastructure in UK ports and harbors consistently coincides with Marine Protected Area designation. Under UK Marine Protected Area designations, vulnerable seabed habitats such as seagrass beds require protection and/or restoration. Mooring and anchoring activity has coincided with increasing concerns over the conservation status of the climate-buffering properties of seagrass beds in the literature and from empirical studies. Up until this study, there has yet to be a significant UK based trial of a number of modified moorings to see their impact on the reduction in pressure on vulnerable benthic habitats. In May 2019, we installed and tested five Advanced Mooring Systems (AMS) in Cawsand Bay, Plymouth Sound, UK. A further 10 such devices were installed in 2021 after the COVID 19 pandemic. The original five devices tested were 'Stirling' systems, whereby the rode is raised above the seabed by use of several submerged floats set at 1.5–2 m intervals along the chain, leading to a top mark that secures the vessel. Each AMS were attached to the seabed using helical screwpiles by commercial divers using a waterproof hydraulic wrench. The devices have held securely since May 2019, and monitoring of seagrass around these five moorings has occurred regularly (at approximately 6 monthly intervals) between May 2019 and May 2023. No seeding or transplantation to prime seagrass recovery has taken place around the base of the moorings during this period. Nevertheless, during the sixth dive survey in May 2023, 4 years after installation, a 212% increase in seagrass density was recorded within the zone previously abraded by the moorings and riser chains. Blade length of the longest seagrass shoots has also increased over the test period. Semi-structured interviews were held with participants in the trial from boat users, NGOs and government agencies to ascertain attitudes and responses to seagrass conservation and the use of AMS. Interaction with stakeholders are important to securing positive community buy-in to such interventions. We recommend that for small sailing craft and powerboats these systems provide a fit-for-purpose engineering and ecological solution to support the restoration of seagrass beds, but that such initiatives must be accompanied by significant understanding and interaction with local stakeholders. [ABSTRACT FROM AUTHOR]

Seagrass meadows provide essential ecosystem services but have been strongly declining over the past. Due to their incapability to recover effectively naturally, assisted restoration is used. This study aimed to test textile fabrics from natural derivatives to serve as carrier substrates for seagrass transplantation. The use of biotextile fabrics should enable seagrasses to better withstand hydrodynamic forces, especially in high‐energy areas and during autumn and winter storms in the initial phase of restoration, thereby increasing restoration success. Here, the biodegradation behavior of three natural textiles was assessed in different configurations. Coir, sisal, and jute meshes were fixed on the top and bottom of a coir nonwoven mat, forming a so‐called “sandwich structure.” Specimens were buried in the Ria Formosa Lagoon, Portugal, and retrieved weekly within the first months of burial and subsequently monthly over a total period of 3 months. Weight, tensile strength, and oxygen consumption rate were used as descriptors for biodegradation and tested after each retrieval. The results obtained in this study were discussed in the context of the application of the tested materials on Zostera marina transplants. Due to experimental errors, these results are solely used for discussion purposes in a conservative manner. Based on the three descriptors, coir mesh was the least degraded by the end of the experiment. Yet, it is vital to analyze the microbiome in a study site to understand the biodegradation process and based on that select a textile material. Coir fibers appear to be a good choice in highly biologically active areas to prolong the degradation process, whereas in areas with less activity sisal could be sufficient and even beneficial through the release of compounds that foster vegetations induced by degradation. [ABSTRACT FROM AUTHOR]

Genetic diversity can modulate a population's response to a changing environment and plays a critical role in its ecological function. While multiple processes act to maintain genetic diversity, sexual reproduction remains the primary driving force. Eelgrass (Zostera marina) is an important habitat‐forming species found in temperate coastal ecosystems across the globe. Recent increases in sea surface temperatures have resulted in shifts to a mixed‐annual life‐history strategy (i.e., displaying characteristics of both annual and perennial meadows) at its southern edge‐of‐range. Given that mating systems are intimately linked to standing levels of genetic variation, understanding the scope of sexual reproduction can illuminate the processes that shape genetic diversity. To characterize edge‐of‐range eelgrass mating systems, developing seeds on flowering Z. marina shoots were genotyped from three meadows in Topsail, North Carolina. In all meadows, levels of multiple mating were high, with shoots pollinated by an average of eight sires (range: 3–16). The number of fertilized seeds (i.e., reproductive success) varied significantly across sires (range: 1–25) and was positively correlated with both individual heterozygosity and self‐fertilization. Outcrossing rates were high (approx. 70%) and varied across spathes. No clones were detected, and kinship among sampled flowering shoots was low, supporting observed patterns of reproductive output. Given the role that genetic diversity plays in enhancing resistance to and resilience from ecological disturbance, disentangling the links between life history, sexual reproduction, and genetic variation will aid in informing the management and conservation of this key foundation species. This study provides a thorough description of fine‐scale patterns in Zostera marina's mating system at the species' southern edge‐of‐range, an area where eelgrass experiences frequent summer heat stress. Sampled populations displayed a reliance on sexual recruitment, and male quality was linked to reproductive success. Our findings serve as stepping stones to further understand the evolutionary processes underpinning seagrass genetic composition and life history, which is essential for informed conservation and management. [ABSTRACT FROM AUTHOR]

Extensive subtidal eelgrass (Zostera marina) meadows (~150 km²) once grew in the Dutch Wadden Sea, supporting diverse species communities, but disappeared in the 1930s and have been absent ever since. Identifying the most critical bottlenecks for eelgrass survival is a crucial first step for reintroduction through active restoration measures. Seagrasses are ecosystem engineers, inducing self-facilitating feedbacks that ameliorate stressful conditions. Consequently, once seagrass, including its self-facilitating feedbacks, is lost, reintroduction can be challenging. Therefore, we aimed to test whether 1) sediment stabilization and 2) hydrodynamic stress relief would facilitate eelgrass survival in a field experiment replicated at two sites in the Dutch Wadden Sea. We induced feedbacks using biodegradable root-mimicking structures (BESE-elements) and sandbag barriers. Root mimics had a significant positive effect, increasing the chances of short-term survival by +67% compared to controls. Contrary to our expectations, barriers decreased short-term survival probabilities by -26%, likely due to hydrodynamic turbulence created by the barrier edges, leading to high erosion rates (-14 cm). Site selection proved crucial as short-term survival was entirely negated on one of the two study sites after five weeks due to high floating and epiphytic macroalgae loads. No long-term survival occurred, as plants died at the other site two weeks later. Overall, we found that sediment stabilization by root-mimicking structures was promising, whereas manipulating hydrodynamic forces using sandbag barriers had adverse effects. A mechanistic understanding of transplant failures is required before attempting large-scale restoration. Our study indicates that for seagrass restoration in the Wadden Sea, one should carefully consider 1) the reintroduction of positive feedbacks through restoration tools, 2) donor population choice and transplantation timing, and 3) site selection based on local biotic and abiotic conditions. Optimizing these restoration facets might lower additive stress to a degree that allows long-term survival. [ABSTRACT FROM AUTHOR]

The ascorbate-glutathione (AsA-GSH) cycle plays a critical role in scavenging hydrogen peroxide in plants and contributes significantly to plant stress tolerance. This study examines the cycle's response in Zostera marina seedlings to warming, specifically under conditions of abnormal sea temperature increase. Three temperature gradients were established: 18°C (control group), 23°C (high-temperature group), and 28°C (abnormally high-temperature group). Results after 7 days of exposure to mild high temperature (23°C) showed decreased MDA content in the HT group, increased AsA/DHA ratio, and enhanced activity of enzymes related to the AsA-GSH cycle. However, exposure to extreme high temperatures resulted in increased oxidative damage and redox imbalance in the AHT group. Initially, enzymes associated with the AsA-GSH cycle, such as APX, MDHAR, GPX, and γ-ECS, increased but significantly decreased later under stress. In contrast, DHAR and GaILDH levels significantly rose on the seventh day. Transcriptome analysis revealed upregulation of APX, MDHAR, DHAR, GR, and γ-ECS genes in the HT group, with a decline in other enzyme gene expressions by the seventh day, except for APX. Under extreme high temperatures, APX expression was downregulated early in the stress period, while DHAR was upregulated, indicating Z. marina seedlings can mitigate oxidative damage under short-term high temperatures by activating the AsA-GSH cycle. Conversely, extreme high temperatures may inhibit this cycle, disrupt redox balance, and adversely affect Z. marina seedling establishment, potentially leading to their demise. [ABSTRACT FROM AUTHOR]

The document is an author index from the European Journal of Clinical Investigation, listing the names of various authors and their corresponding articles, presentations, or posters. It covers a wide range of topics and perspectives in clinical investigation, medical research, and scientific studies. [Extracted from the article]

This document is a collection of abstracts from scientific journals and publications on ecological restoration. The abstracts cover various topics such as coastal and marine communities, economics and ecosystem services, grasslands, invasive species, lakes, rivers, and streams, monitoring and adaptive management, and other communities. Each abstract summarizes a specific study or research project, providing key findings and recommendations. These abstracts offer valuable insights into the field of ecological restoration and can be a useful resource for researchers and practitioners. The topics covered include habitat suitability models for restoration site selection, coral gardening techniques, sea turtle conservation, dung beetle restoration, marine ecosystem monitoring, monarch butterfly mapping, wetland carbon and biodiversity, forest habitat restoration, small mammal associations in prairies, and bird communities in farmland restoration. [Extracted from the article]

Coastal habitat‐forming species provide protection and essential habitat for fisheries but their ability to maintain these services are under threat from novel stressors including rising temperatures. Coastal habitat restoration is a powerful tool to help mitigate the loss of habitat‐forming species, however, many efforts focus on reintroducing a single, imperilled species instead of incorporating alternatives that are more conducive to current and future conditions. Seagrass restoration has seen mixed success in halting local meadow declines but could begin to specifically utilize generalist seagrasses with climate change‐tolerant and opportunistic life history traits including high reproduction rates and rapid growth.Here, we built on decades of successful eelgrass (Zostera marina) restoration in the Chesapeake Bay by experimentally testing seed‐based restoration potential of widgeongrass (Ruppia maritima)—a globally distributed seagrass that can withstand wide ranges of salinities and temperatures. Using field experiments, we evaluated which seeding methods yielded highest widgeongrass survival and growth, tested if seeding widgeongrass adjacent to eelgrass can increase restoration success, and quantified how either seagrass species changes restored bed structure, invertebrate communities, and nitrogen cycling.We found that widgeongrass can be restored via direct seeding in the fall, and that seeding both species maximized total viable restored area. Our pilot restoration area increased by 98% because we seeded widgeongrass in shallow, high temperature waters that are currently unsuitable for eelgrass survival and thus, would remain unseeded via only eelgrass restoration efforts. Restored widgeongrass had higher faunal diversity and double animal abundance per plant biomass than restored eelgrass, whereas restored eelgrass produced three times greater plant biomass per unit area and higher nitrogen recycling in the sediment.Synthesis and applications. Overall, we provide evidence that supplementing opportunistic, generalist species into habitat restoration is a proactive approach to combat climate change impacts. Specifically, these species can increase trait diversity which, for our study, increased total habitat area restored—a key factor to promote seagrass beds' facilitation cascades, stability, and grass persistence through changing environments. Now, we call for tests to determine if the benefits of restoration with generalist species alone or in conjunction with historically dominant taxa are broadly transferrable to restoration in other marine and terrestrial habitats. [ABSTRACT FROM AUTHOR]

"Beauty Regimes: A History of Power and Modern Empire in the Philippines, 1898–1941" by Genevieve Alva Clutario is a book that explores the role of beauty and fashion in the Philippines during the transition from Spanish to United States to Japanese imperial regimes. Clutario analyzes the impact of sartorial material culture on people and empire, highlighting the centrality of clothes, cloth, and spectacle during this colonial period. The book delves into the sartorial practices of Filipina women, the role of spectacle in reaffirming U.S. economic stability, the transnational Philippine beautification industry, and the use of fashion to reaffirm identity and challenge social hierarchies. Clutario's research is thorough and provides valuable insights into the intersections of gender, empire, race, and class in the Philippines. [Extracted from the article]

Eelgrass (Zostera marina) loss occurs worldwide due to increasing water temperatures and decreasing water quality. In the U.S., widgeongrass (Ruppia maritima), a more heat-tolerant seagrass species, is replacing eelgrass in certain areas. Seagrasses enhance sediment denitrification, which helps to mitigate excess nitrogen in coastal systems. Widgeongrass and eelgrass have different characteristics, which may affect sediment nitrogen cycling. We compared net N2 fluxes from vegetated areas (eelgrass and widgeongrass beds, using intact cores that included sediment and plants) and adjacent unvegetated areas from the York River, in the lower Chesapeake Bay during the spring and summer of one year. We found that seagrass biomass, sediment organic matter, and NH4+ fluxes were significantly higher in eelgrass beds than in widgeongrass beds. Eelgrass was also net denitrifying during both seasons, while widgeongrass was only net denitrifying in the summer. Despite differences in the spring, the seagrass beds had a similar rate of N2 production in the summer and both had higher denitrification rates than unvegetated sediments. Both species are important ecosystem components that can help to mitigate eutrophication in coastal areas. However, as the relative composition of these species continues to change, differences in sediment nitrogen cycling may affect regional denitrification capacity. [ABSTRACT FROM AUTHOR]

Zostera marina is an ecologically valuable species that has been declining due to anthropogenic environmental stressors. In this study, spatial and temporal indicators of eelgrass stress, such as coverage and biomass, were compared with the isotopic composition of C, N, and S to understand the mechanism(s) of plant stress. Eelgrass samples were collected in June, July, and August of 2020 at five stations along an estuary spatial gradient in the southern Gulf of St. Lawrence to measure above- and below-ground biomass and tissue isotopes in eelgrass leaves and roots/rhizomes. Eelgrass biomass was lowest at the innermost sampling station, which coincided with eutrophication-induced hypoxia relative to outer sampling stations. δ13C levels at the upstream station were depleted compared to downstream stations. Comparatively, δ15N and δ34S findings were not correlated with plant biomass. Thus, sulfide intrusion was not a major stressor for eelgrass in this estuary. Between the years 2014 and 2020, eelgrass coverage was found to have increased, which coincided with high and low recorded external nutrient loads from the Wheatley River, respectively. Ultimately, these findings indicate that isotopic composition and biomass can be useful in assessing the health of eelgrass in temperate estuaries. [ABSTRACT FROM AUTHOR]

Concentrations of heavy metals in live and dead leaves, stems, rhizomes and roots of the seagrass Zostera marina Linnaeus, 1753 are analyzed in the study. On the basis of the concentration, the metals are arranged in the following order: Fe > Mn > Zn > Cu > Pb > Ni >Cd. Differences in Fe, Pb, Ni, and Cd for live and dead leaves are revealed. The factor of sediment enrichment in heavy metals from dead leaves is calculated. The enrichment factor for the studied metals changed in the order Cu > Pb > Zn > Ni > Mn, and the value of solubility product [–log(SP)] for sulfides of the above-listed metals changed in the same order. [ABSTRACT FROM AUTHOR]

The extent of parallel genomic responses to similar selective pressures depends on a complex array of environmental, demographic, and evolutionary forces. Laboratory experiments with replicated selective pressures yield mixed outcomes under controlled conditions and our understanding of genomic parallelism in the wild is limited to a few well-established systems. Here, we examine genomic signals of selection in the eelgrass Zostera marina across temperature gradients in adjacent embayments. Although we find many genomic regions with signals of selection within each bay there is very little overlap in signals of selection at the SNP level, despite most polymorphisms being shared across bays. We do find overlap at the gene level, potentially suggesting multiple mutational pathways to the same phenotype. Using polygenic models we find that some sets of candidate SNPs are able to predict temperature across both bays, suggesting that small but parallel shifts in allele frequencies may be missed by independent genome scans. Together, these results highlight the continuous rather than binary nature of parallel evolution in polygenic traits and the complexity of evolutionary predictability.

Species persist through resistance and recovery traits induced by natural stressors. Whether human activities exacerbate or moderate the effects of natural stressors is an open question. Because eelgrass (Zostera marina) creates coastal habitat, its response to natural stressors and human activities is of particular management importance. In this study, traits of intertidal eelgrass were examined across cumulative stressors of emersion and oyster culture, including two culture types: oysters grown directly on sediment (ground culture) or supported by gear above the sediment (off-bottom culture). Summer eelgrass was larger above- and below-ground and branched less than in spring, while density and cover were similar seasonally but declined at higher elevation and in ground culture. Eelgrass traits were divided into those related to resistance (larger above-ground size and below-ground storage) and recovery (increased flowering, branching, and rhizome extension). Resistance traits responded additively to intertidal elevation and oyster culture, with above- and below-ground size reduced in all conditions except that rhizome mass was maintained in ground culture. Smaller above-ground size may confer resistance to emersion stress, as a departure from expectations for other stressors. For resilience traits, flowering increased and internode length declined at higher elevation, whereas these traits did not change in ground culture, and off-bottom culture was associated with shorter internodes (additive cumulative stressor) and tended to moderate the enhanced flowering at higher elevations (non-additive, P=0.058). Transitory disturbance in ground culture may reduce eelgrass density with few effects on resilience, whereas off-bottom culture involves longer-term gear placement and trait responses by eelgrass.