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Seagrass meadows play a key role in the global carbon cycle through storing carbon in their biomass and soils. However, the lack of global assessments of carbon stocks in seagrass biomass and net primary production (NPP) limits our understanding of their role in the carbon cycle. Here, we provide global estimates of biomass carbon stocks and NPP encompassing seagrasses with different life-history strategies, across bioregions and 66 countries. Seagrass meadows show up to 800-fold differences in biomass across different life-history strategies and bioregions (mean ± SE; 1551 ± 40 kg C ha −1 ), whereas seagrass NPP (5833 ± 557 kg C ha −1 yr −1 ) ranks among the highest within photosynthetic ecosystems. We estimate seagrass biomass carbon stocks at 24–40 Tg C and NPP at 83–137 Tg C yr −1 within 160,387 to 266,500 km 2 of global seagrass extent. This study showcases the role of seagrasses in the global carbon cycle and provides the basis for their inclusion in carbon crediting schemes towards implementing conservation actions for climate change mitigation. Seagrass meadows store 24–40 million tons of carbon and fix 83–137 million tons of carbon annually in their biomass, ranking among the most productive ecosystems on Earth. Seagrass conservation can contribute to climate change mitigation.

Ecologically dominant species often define ecosystem states, but as human disturbances intensify, their subordinate counterparts increasingly displace them. We consider the duality of disturbance by examining how environmental drivers can simultaneously act as a stressor to dominant species and as a resource to subordinates. Using a model ecosystem, we demonstrate that CO2-driven interactions between species can account for such reversals in dominance; i.e., the displacement of dominants (kelp forests) by subordinates (turf algae). We established that CO2 enrichment had a direct positive effect on productivity of turfs, but a negligible effect on kelp. CO2 enrichment further suppressed the abundance and feeding rate of the primary grazer of turfs (sea urchins), but had an opposite effect on the minor grazer (gastropods). Thus, boosted production of subordinate producers, exacerbated by a net reduction in its consumption by primary grazers, accounts for community change (i.e., turf displacing kelp). Ecosystem collapse, therefore, is more likely when resource enrichment alters competitive dominance of producers, and consumers fail to compensate. By recognizing such duality in the responses of interacting species to disturbance, which may stabilize or exacerbate change, we can begin to understand how intensifying human disturbances determine whether or not ecosystems undergo phase shifts.

Metabarcoding has improved the way we understand plants within our environment, from their ecology and conservation to invasive species management. The notion of identifying plant taxa within environmental samples relies on the ability to match unknown sequences to known reference libraries. Without comprehensive reference databases, species can go undetected or be incorrectly assigned, leading to false‐positive and false‐negative detections. To improve our ability to generate reference sequence databases, we developed a targeted capture approach using the OZBaits_CP V1.0 set, designed to capture chloroplast gene regions across the entirety of flowering plant diversity. We focused on generating a reference database for coastal temperate plant species given the lack of reference sequences for these taxa. Our approach was successful across all specimens with a target gene recovery rate of 92%, which was achieved in a single assay (i.e., samples were pooled), thus making this approach much faster and more efficient than standard barcoding. Further testing of this database highlighted 80% of all samples could be discriminated to family level across all gene regions with some genes achieving greater resolution than others—which was also dependent on the taxon of interest. Thus, we demonstrate the importance of generating reference sequences across multiple chloroplast gene regions as no single loci are sufficient to discriminate across all plant groups. The targeted capture approach outlined in this study provides a way forward to achieve this. This study has applied a targeted capture approach to generate a DNA reference sequence database for coastal temperate flora. We implemented a bait set designed to capture 20 chloroplast gene regions in a single assay, thus highlighting an approach for efficient generation of plant reference databases across multiple gene regions.

Anthropogenic activities are causing detrimental changes to coastal plants– namely seagrass, mangrove, and tidal marshes. Looking beyond recent times to past vegetation dynamics is critical to assess the response and resilience of an environment to change. Here, we develop a high-resolution multi-proxy approach, providing a new evidence base to decipher long-term change in coastal plant communities. Combining targeted environmental DNA analysis with chemical analysis of soils, we reconstructed 4,000 years of change at a temperate wetland on Torrens Island South Australia and identified an ecosystem shift that occurred ~ 1000 years ago. What was once a subtidal seagrass system shifted to an intertidal mangrove environment that persists at this site today. We demonstrate that high-resolution historical changes in coastal vegetation can be attained using these proxies. This approach could be applied to other ecosystems to improve the way we protect, conserve, and restore vegetated ecosystems.

Olearia pannosa is a plant species listed as vulnerable in Australia. Two subspecies are currently recognised (O. pannosa subsp. pannosa (silver daisy) and O. pannosa subsp. cardiophylla (velvet daisy)), which have overlapping ranges but distinct leaf shape. Remnant populations face threats from habitat fragmentation and climate change. We analysed range-wide genomic data and leaf shape variation to assess population diversity and divergence and to inform conservation management strategies. We detected three distinct genetic groupings and a likely cryptic species. Samples identified as O. pannosa subsp. cardiophylla from the Flinders Ranges in South Australia were genetically distinct from all other samples and likely form a separate, range-restricted species. Remaining samples formed two genetic clusters, which aligned with leaf shape differences but not fully with current subspecies classifications. Levels of genetic diversity and inbreeding differed between the three genetic groups, suggesting each requires a separate management strategy. Additionally, we tested for associations between genetic and environmental variation and carried out habitat suitability modelling for O. pannosa subsp. pannosa populations. We found mean annual maximum temperature explained a significant proportion of genomic variance. Habitat suitability modelling identified mean summer maximum temperature, precipitation seasonality and mean annual rainfall as constraints on the distribution of O. pannosa subsp. pannosa, highlighting increasing aridity as a threat for populations located near suitability thresholds. Our results suggest maximum temperature is an important agent of selection on O. pannosa subsp. pannosa and should be considered in conservation strategies. We recommend taxonomic revision of O. pannosa and provide conservation management recommendations.

Environmental DNA (eDNA), elemental and mineralogical analyses of soil have been shown to be specific to their source material, prompting consideration of using the airborne fraction of soil (dust) for forensic intelligence work. Dust is ubiquitous in the environment and is easily transferred to items belonging to a person of interest, making dust analysis an ideal tool in forensic casework. The advent of Massive Parallel Sequencing technologies means metabarcoding of eDNA can uncover bacterial, fungal, and even plant genetic fingerprints in dust particles. Combining this with elemental and mineralogical compositions offers multiple, complementary lines of evidence for tracing the origin of an unknown dust sample. This is particularly pertinent when recovering dust from a person of interest to ascertain where they may have travelled. Prior to proposing dust as a forensic trace material, however, the optimum sampling protocols and detection limits need to be established to place parameters around its utility in this context. We tested several approaches to collecting dust from different materials and determined the lowest quantity of dust that could be analysed for eDNA, elemental composition and mineralogy, whilst still yielding results capable of distinguishing between sites. We found that fungal eDNA profiles could be obtained from multiple sample types and that tape lifts were the optimum collection method for discriminating between sites. We successfully recovered both fungal and bacterial eDNA profiles down to 3 mg of dust (the lowest tested quantity) and recovered elemental and mineralogical compositions for all tested sample quantities. We show that dust can be reliably recovered from different sample types, using different sampling techniques, and that fungi and bacteria, as well as elemental and mineralogical profiles, can be generated from small sample quantities, highlighting the utility of dust for forensic intelligence. •The ubiquitous nature of dust makes it a useful tool for forensic intelligence.•eDNA, biogeochemistry and sampling method were tested on different dust samples.•Both tape lifting and swabbing methods recover discriminatory eDNA dust profiles.•Dust eDNA was discriminatory between sites even at very low starting mass.•The relative elements and minerals within dust are discriminatory between sites.

Molecular technologies have facilitated the expansion of biodiversity assessments across a broad range of organisms and aquatic systems. Environmental DNA (eDNA) and environmental RNA (eRNA), collectively referred to as environmental nucleic acids (eNAs), have revolutionized biodiversity monitoring due to their noninvasive nature and high‐resolution capabilities when compared to traditional survey methods. While eNA applications have grown exponentially over the past decade, methodological inconsistencies hinder reproducibility and comparability. To assess the current state of eNA methodologies in aquatic ecology, we conducted a systematic review of 300 peer‐reviewed eNA studies that assess ecological communities across diverse aquatic systems. Of these papers, 291 examine eDNA, four examine eRNA, and five consider both eDNA and eRNA. The small number of eRNA studies compared to eDNA highlights the eRNA field is in its infancy. Of the eNA studies looked at, we found a clear geographic bias, with approximately 50% of all eNA studies occurring in six high‐income countries, while less than 10% of eNA studies occur across South America and Africa. Further, we report a lack of methodological standardization across eNA studies, showing high variability in water filtration volume, filter material, filter pore size, eNA extraction method, marker choice, and bioinformatic pipelines. We further highlight that incomplete reference sequence databases for both eRNA and eDNA limit taxonomic assignment and biodiversity inferences. Finally, we identify a systematic issue across eNA studies in community ecology: missing methodological details, which compromise reproducibility, especially in newly emerging eRNA applications. To facilitate the standardization of eNA monitoring across aquatic systems and permit the further integration of eNA applications in biodiversity monitoring, we recommend the improvement of reference databases alongside guidelines that encourage methodological transparency. We conducted a systematic review of 300 peer‐reviewed eDNA and eRNA studies in aquatic ecology and found a geographical bias, with the majority of studies concentrated in high‐income countries and limited representation from South America and Africa. We also observed a lack of methodological standardization, including variations in filtration volume, filter material, eDNA and eRNA extraction method, marker choice, and bioinformatic pipelines, emphasizing the need for guidelines to promote methodological transparency and reproducibility in eDNA and eRNA monitoring across aquatic systems.

Decades of research within political science, political communication, and mass media found pervasive gender biased media coverage of female political candidates. However, recent research suggests that gender stereotypes do not have a consistent effect in all campaign environments and when gender stereotypes are not activated, female candidates are not disadvantaged. As a result, if we see a reduction in reliance on gender stereotypes in the media, female candidates should enjoy a more level playing field. In this analysis, we focus on mass media’s coverage of female candidates in elite executive political races. This study conducts a content analysis of media coverage of three recent women candidates for the United States’ highest executive offices: Senator Hillary Clinton, Congresswoman Michelle Bachmann, and Governor Sarah Palin. Our analysis of newspapers and television news coverage confirms the media do not discuss female and male candidates in neutral terms, but instead fall back onto traditional gender stereotypes and emphasize female candidates’ physical appearances and family roles far more frequently than they do for male candidates. This may, in turn, prime gender stereotypes in voters, impair candidates’ fundraising ability, and limit the electoral ambition of future generations of female candidates.

Metabarcoding of plant DNA recovered from environmental samples, termed environmental DNA (eDNA), has been used to detect invasive species, track biodiversity changes and reconstruct past ecosystems. The P6 loop of the trnL intron is the most widely utilized gene region for metabarcoding plants due to the short fragment length and subsequent ease of recovery from degraded DNA, which is characteristic of environmental samples. However, the taxonomic resolution for this gene region is limited, often precluding species level identification. Additionally, targeting gene regions using universal primers can bias results as some taxa will amplify more effectively than others. To increase the ability of DNA metabarcoding to better resolve flowering plant species (angiosperms) within environmental samples, and reduce bias in amplification, we developed a multi-gene targeted capture method that simultaneously targets 20 chloroplast gene regions in a single assay across all flowering plant species. Using this approach, we effectively recovered multiple chloroplast gene regions for three species within artificial DNA mixtures down to 0.001 ng/uL of DNA. We tested the detection level of this approach, successfully recovering target genes for 10 flowering plant species. Finally, we applied this approach to sediment samples containing unknown compositions of environmental DNA and confidently detected plant species that were later verified with observation data. Targeting multiple chloroplast gene regions in environmental samples enabled species-level information to be recovered from complex DNA mixtures. Thus, the method developed here, confers an improved level of data on community composition, which can be used to better understand flowering plant assemblages in environmental samples. Competing Interest Statement The authors have declared no competing interest.

Women with bacterial vaginosis (BV), an imbalance of the vaginal microbiome, are more likely to be colonized by potential pathogens such as Fusobacterium nucleatum, a bacterium linked with intrauterine infection and preterm birth. However, the conditions and mechanisms supporting pathogen colonization during vaginal dysbiosis remain obscure. We demonstrate that sialidase activity, a diagnostic feature of BV, promoted F. nucleatum foraging and growth on mammalian sialoglycans, a nutrient resource that was otherwise inaccessible because of the lack of endogenous F. nucleatum sialidase. In mice with sialidase-producing vaginal microbiotas, mutant F. nucleatum unable to consume sialic acids was impaired in vaginal colonization. These experiments in mice also led to the discovery that F. nucleatum may also \"give back\" to the community by reinforcing sialidase activity, a biochemical feature of human dysbiosis. Using human vaginal bacterial communities, we show that F. nucleatum supported robust outgrowth of Gardnerella vaginalis, a major sialidase producer and one of the most abundant organisms in BV. These results illustrate that mutually beneficial relationships between vaginal bacteria support pathogen colonization and may help maintain features of dysbiosis. These findings challenge the simplistic dogma that the mere absence of \"healthy\" lactobacilli is the sole mechanism that creates a permissive environment for pathogens during vaginal dysbiosis. Given the ubiquity of F. nucleatum in the human mouth, these studies also suggest a possible mechanism underlying links between vaginal dysbiosis and oral sex.