Communications Earth & Environment
○ Springer Science and Business Media LLC
Preprints posted in the last 30 days, ranked by how well they match Communications Earth & Environment's content profile, based on 14 papers previously published here. The average preprint has a 0.03% match score for this journal, so anything above that is already an above-average fit.
Young, S. C. E.; Watkins, H. V.; Brownlee, S. F.; Yan, H. F.; Cote, I. M.
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Mountain ecosystems face unprecedented pressures from anthropogenic activities and climate change, challenging the productivity of these vital habitats. In the Tien Shan mountains, understanding localized responses to these pressures is often hindered by the coarse spatiotemporal resolutions of available data. To address this, we combined high-resolution satellite imagery (1997-2021) to map land-cover dynamics in the Naryn oblast, Kyrgyzstan across a gradient of grazing intensities. We classified and quantified land-cover distribution over 24 years, investigating the roles of topography, elevation, and anthropogenic disturbances as drivers of change. Our results identify intermediate elevations, high degrees of disturbance, and the interaction between the two as the primary contributors to recent transitions in grassland, forest, and barren habitats. By integrating Landsat analysis-ready data, European Space Agency WorldCover dataset and digital elevation models at fine spatial scales, we provide valuable contemporary and historical landscape and habitat-level insights and a high-resolution framework for disentangling climate-driven shifts from land-use impacts. These findings highlight the urgency of localized management in remote, data-poor regions where rapid environmental change threatens both biodiversity and pastoral livelihoods. Our work serves as a critical baseline for characterizing the adaptability of semi-arid mountain rangelands under escalating global and regional pressures.
Karim, M. R.; Thomas, S.
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The contribution of tree foliage to atmospheric methane (CH4) and nitrous oxide (N2O) fluxes remains a major uncertainty in global GHG budgets. We made repeated in situ measurements of foliar CH4 and N2O fluxes across 25 temperate tree species interplanted at a forest restoration site using high-resolution laser spectroscopy. Tree foliage was consistently a net CH4 sink and a net N2O source in all species. Foliar CH4 oxidation increased by [~]33% in fall relative to spring and was [~]3-fold higher in shade-tolerant than shade-intolerant angiosperm species. Species differences accounted for most of the variability in fluxes, while correlations with soil emissions were comparatively weak. Microbial DNA sequencing revealed that the highest CH4-oxidizing angiosperm species (Tilia americana) harbored abundant Type I methanotrophs, whereas the lowest-oxidizing species (Prunus virginiana) had nearly 100-fold lower methanotroph abundance, with a foliar microbial community dominated by facultative methylotrophs. Global warming potential (GWP) scaling indicates that foliar CH4 uptake overwhelmingly dominates the net climate forcing effect. Our results suggest that the large and predictable differences in foliar CH4 uptake among tree species and associated differences in foliar microbial communities are of importance in understanding and potentially enhancing the global terrestrial CH4 sink.
Vietorisz, C.; Tatsumi, C.; Werbin, Z.; Bhatnagar, J.
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Soil microbes support life on Earth by regulating the availability of nutrients in soils, yet we lack a fundamental, baseline knowledge of which fungi and bacteria are associated with specific soil nitrogen (N) cycling processes across ecosystems. We identified functional and taxonomic groups of fungi and bacteria that are associated with net ammonification and nitrification rates in soils from diverse ecosystems across the United States, including the environmental contexts where these relationships exist. To accomplish this, we co-analyzed soil, microbial, plant, and climatic data from 19 sites across the U.S. National Ecological Observatory Network (NEON). Distinct microbial groups were associated with net ammonification versus nitrification rates, highlighting the need to measure and model these two processes separately. The relative abundance of several microbial groups known for their N-decomposition abilities (i.e., Acidobacteriae, Bacteroidia, Saccharomycetes yeasts, ectomycorrhizal fungi) were positively associated with net ammonification rates across diverse environmental conditions. Meanwhile, pathogenic fungi, copiotrophic bacteria, and bacterial classes containing denitrifying bacteria were positively associated with net nitrification rates in many wet, hot, and high-N environments. These results deepen our understanding of soil microbiome ecology and represent a practical starting point to develop microbial-explicit biogeochemical cycling models at large spatial scales.
El-Khaled, Y. C.; Garcia, F. C.; Santoro, E. P.; Garcias-Bonet, N.; Monti, M.; Teixeira, M. A. L.; Justo, M. S. S.; Gil-Ramos, G.; Sempere-Valverde, J.; Kolbasova, G.; Beenham, L.; Duarte, G.; Martins, D.; Antony, C. P.; Thomas, T.; Carvalho, S.; Peixoto, R. S.
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Probiotics can enhance coral thermal tolerance, yet their ecosystem-level effects remain unknown. Here, we present the first long-term in-situ test of whether coral-targeted probiotics influence adjacent cryptobenthic reef communities during a record marine heatwave. Probiotics were applied to Pocillopora favosa and Acropora spp. coral colonies for 18 months, spanning the fourth global bleaching event. Cryptobenthic communities were assessed using biomimetic monitoring structures integrating biodiversity surveys, molecular profiling, microbial network analyses, and metabolic assays. Before the heatwave, probiotic and control patches were comparable across structural, microbial, and functional metrics. Following thermal stress, control patches exhibited pronounced losses of cryptobenthic invertebrate abundance and taxonomic breadth, microbial network fragmentation, and net carbonate dissolution. In contrast, probiotic-treated patches retained higher biodiversity, cohesive microbial interaction architectures, and positive calcification. These findings demonstrate that coral-targeted probiotics can scale from host-level intervention to buffer adjacent ecosystem-level responses to extreme marine heatwaves under accelerating climate change. TeaserA coral-targeted probiotic strategy enhances multi-trophic resilience under heat stress.
Peacock, S. J.; Cheung, W. W. L.; Connors, B. M.; Crozier, L. G.; Grant, S.; Hertz, E.; Hunt, B. P. V.; Iacarella, J.; Lagasse, C. R.; Moore, R. D.; Moore, J. W.; Nicolas-Robinne, F.; Porter, M.; Schnorbus, M.; Wilson, S. M.; Connors, K.
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Climate change can affect salmon and steelhead (Oncorhynchus spp.) throughout their anadromous life cycles, yet there have been no assessments of which Canadian populations face the greatest exposure. We developed a framework to quantify relative climate change exposure of salmon and steelhead populations based on the spatial and temporal distribution of different life stages. Exposure was calculated from climate model projections for freshwater and marine climate variables considering unique impact thresholds for each population and life stage. We applied this framework to 60 Conservation Units of Pacific salmon and steelhead in the Fraser River basin, British Columbia. Lake-type sockeye had the highest exposure, driven by elevated stream temperatures during adult freshwater migration and spawning stages and relatively low thermal tolerance of marine stages. Chinook salmon were the next most exposed, while coho, pink, and chum salmon had relatively low exposure. Uniquely, steelhead exposure was driven by high stream temperatures during incubation. Our framework is broadly applicable, and our findings provide critical input for climate change vulnerability assessments and forward-looking resilience planning for Pacific salmon.
Hopf, J. K.; Giraldo-Ospina, A.; Caselle, J.; Kroeker, K.; Carr, M.; Hastings, A.; White, J. W.
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Marine protected areas (MPAs) are increasingly promoted as climate mitigation tools, yet guidance on their placement to maximize resilience against climate stressors like marine heatwaves remains limited. Here, we develop MPA placement guidelines that explicitly consider a mechanistic pathway through which MPAs could enhance kelp forest resilience to heatwaves: protecting fishery-targeted urchin predators to prevent kelp overgrazing. Using a spatially explicit, tri-trophic model of California kelp forests, we evaluate alternative MPA configurations across a hypothetical coastline where half the habitat experiences an increased probability of experiencing heatwaves. We found that effective MPA placement depends on whether MPAs are being newly established or reconfigured within an existing network, and that among-patch connectivity and spillover played vital roles in the relative effectiveness of different MPA configurations. Changes in resilience occurred primarily at the patch scale, with trade-offs between increased within-MPA resilience and decreased resilience in some fished areas, resulting in minimal coastwide population effects. For example, for new MPAs, large single MPAs within heatwave-prone areas maximized within-MPA resilience gains, while multiple small MPAs in heatwave refugia best supported whole-coast resilience. When reconfiguring established networks, expanding existing MPAs in refugia areas was most effective. We also demonstrate the importance of considering MPA recovery timescales: for example, relocating old MPAs to heatwave refugia yielded minimal short-term benefits due to the loss of rebuilt, previously fished, predator biomass. Our findings demonstrate that climate-adaptive marine planning should explicitly consider the spatiotemporal implications of trophic cascades, connectivity, and transient population dynamics to support ecosystem resilience.
Jolles, J. W.; Gismann, J. W.; Cornet Sanz, A.; Bonada, N.
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Intermittent rivers and ephemeral streams (IRES) are increasingly recognised as ecologically important freshwater systems, yet little is known about how fish behave during the critical disconnected-pool phase, when drying confines them to isolated refuge pools. We combined high-resolution orthomapping and depth reconstructions with repeated whole-pool observations and focal follows to quantify microhabitat use and fine-scale movements of fish in refuge pools of an intermittent Mediterranean river. Fish used only a small fraction of the available pool area and consistently preferred deeper, refuge-associated microhabitats. Body size strongly structured behaviour: fry and small juveniles concentrated in shallow margins and showed short, tortuous movements, whereas larger individuals occupied deeper, more structured areas, moved farther, and were more closely associated with refuges. These patterns were broadly similar in drying and non-drying pools and changed little as water levels declined. After rewetting, fish showed reduced activity and weaker depth-biased habitat use, revealing that drying history leaves carry-over imprints on behaviour even after water levels recover. Our results show that refuge pools are not homogeneous water bodies, but internally structured habitats whose fine-scale characteristics shape how fish cope with drying, underscoring their conservation importance in increasingly intermittent rivers.
Villafana, J.; Almendras, D.; Gonzalez-Aragon, D.; Concha, F.; Guzman-Castellanos, A.; Contreras, I.; Buldrini, K.; Oyanadel-Urbina, P.; Sandoval, C.; Miranda, B.; Mazo, G.; Cardenas, F.; Valdivia, M.; Pequeno, G.; Lara, C.; Rivadeneira, M.
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The yellownose skate (Dipturus chilensis) is an endangered skate with a narrow distribution in the southeastern Pacific, facing intense fishing pressure and potential climate threats. Using a species distribution model, we projected the current and future distribution of D. chilensis under contrasting climate change scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) for mid-century (2050) and end-of-century (2100). Our models, which demonstrated robust predictive performance significantly better than random expectations, identified maximum temperature and minimum oxygen as the primary environmental drivers of habitat suitability. Projections revealed a consistent poleward range shift towards the Channels and Fjords of Southern Chile ecoregion across all scenarios. While localized habitat loss was projected in Central Chile and Araucanian ecoregions, particularly under high emissions (SSP5-8.5), these losses were outweighed by southern expansions, leading to a net increase in total suitable habitat by 2100. These findings underscore the critical need for climate-adaptive management strategies, including the protection of emerging southern refugia and dynamic fisheries regulations, to ensure the long-term persistence of D. chilensis.
Wu, D.; Ciren, Q.; Jia, Z.; Schwalb, A.; Guggenberger, G.; Wang, S.; Dorji, T.; Pester, M.
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Plant species loss and nitrogen fertilization affect grassland biodiversity. However, their interactive effects on plant communities, soil properties, and the soil microbiome remain insufficiently understood. We analyzed how the removal of plant species, with and without urea addition, influenced plant diversity, soil properties, and soil bacterial communities in a Tibetan Plateau grassland. Continuous plant species removal and urea addition over seven years modified plant beta-diversity equally strong, while urea exerted a stronger negative effect on plant alpha-diversity. Both, plant species removal and urea addition caused soil acidification and an increase in NO2-/NO-, while dynamics in TOC, TON and TOC: TON were mainly driven by the growing season. Structural equation modeling identified soil acidification via urea addition as the most important indirect driver that negatively affected bacterial alpha-diversity and shifted bacterial beta-diversity. Urea addition also exerted direct negative effects on bacterial alpha- and beta-diversity, causing repression of oligotrophic (Acidobacteriota, Chloroflexota, Planctomycetota, Gemmatimonadota) and stimulation of copiotrophic (Bacillota, Bacteroidota, Pseudomonadota) bacterial taxa. Plant species removal caused slight increases in bacterial alpha-diversity, paralleled by less diverse but more even plant communities. We show that soil acidification by urea fertilization outweighs plant species loss in its negative effect on bacterial soil biodiversity in Tibetan grasslands.
Mueller, K. R.; Morford, S. L.; Kimball, J. S.; Smith, J. T.; Donnelly, P. J.; Naugle, D. E.
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Mesic resources, the late-season herbaceous vegetation found in riparian areas and wet meadows, provide disproportionately important forage and habitat across western U.S. rangelands, yet their response to climatic variability and anthropogenic influences remains poorly understood. Using a 40-year Landsat time series (1984-2024), we quantified trends in late-season productivity (NDVI) across 4.5 million hectares of the sagebrush biome and applied random forest models to distinguish between temporal and spatial predictors of mesic resource productivity. We identified a fundamental shift in how mesic resources respond to drought: from 1984 to 2004, mesic productivity was strongly correlated with drought severity (Palmer Drought Severity Index, R{superscript 2} = 0.92), but this relationship weakened substantially in the next two decades (2005-2024; R{superscript 2} = 0.28), during which time productivity increased despite persistent aridity. Temporal modeling identified rising atmospheric CO2 concentrations as the strongest predictor of this shift, consistent with enhanced plant water-use efficiency under CO2 fertilization. Spatially, large agricultural valley floodplains act as anthropogenic refugia, sustaining productive mesic resources through flood irrigation and subsequent groundwater recharge into late summer. These findings suggest that human water management and physiological shifts in vegetation are currently buffering mesic systems against meteorological drought throughout U.S. rangelands. However, this apparent buffering is spatially heterogeneous and may mask vulnerability to groundwater depletion, shifts in precipitation regimes, and woody encroachment. Sustaining these vital ecosystems will require conservation approaches that go beyond climate monitoring to include balanced management considering both agricultural and ecological water needs and constraints.
Vega, G. M.; Kerkar, A. U.; Nayak, A. R.; McFarland, M.; Lopes, R. M.
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The Mississippi River (MR) is the largest source of freshwater and nutrients to the Gulf of Mexico (GoM), strongly influencing stratification, primary production, and plankton organization. The interaction between buoyant plume waters and denser shelf waters in the northern Gulf of Mexico (nGoM) generates sharp density gradients that can promote fine-scale biological aggregation. We investigated how hydrographic structure associated with the MR plume controls the vertical distribution of plankton during May 2017 using an integrated instrumentation suite that included an in situ digital holographic imaging system (HOLOCAM) coupled with CTD and optical sensors. Phytoplankton thin layers were repeatedly detected at plume-edge stations within or immediately above a compressed pycnocline formed by bottom-trapped saline wedges. These layers were 1.2-3.5 m thick and exhibited chlorophyll-a concentrations up to threefold higher than background levels. The assemblage was dominated by chain-forming diatoms, particularly Chaetoceros debilis and C. socialis, whose local abundance maxima coincided with chlorophyll peaks. In contrast, copepods, appendicularians, and other zooplankton were broadly distributed throughout the upper water column and rarely aggregated within the layers. Redundancy analysis indicated that chlorophyll concentration and stratification intensity were primary drivers of community structure across stations. Satellite imagery revealed rapid short-term variability in plume extent, helping explain differences in stratification and thin layer development among sampling days. Our results demonstrate that salt-wedge dynamics at the plume-shelf interface constitute a key physical mechanism governing transient phytoplankton thin layer formation in the nGoM, while zooplankton responses remain weakly coupled at the temporal scales resolved here.
Arnold, A. E.; Matsushiba, J. H.; Dulvy, N. K.
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Global conservation agreements emphasize protected area coverage targets, such as the Kunming-Montreal Global Biodiversity Frameworks 30x30 target, yet their effectiveness in safeguarding biodiversity remains uncertain. We measure the intersection between marine protected area (MPAs) coverage and the distribution of sharks and rays. Using global range maps and MPA boundaries within national Exclusive Economic Zones, we calculate the percent of species ranges within MPAs, focusing on no-take areas. We reveal significant shortfalls in species-level protection. Within national waters, no Critically Endangered species has more than 5% of its range in no-take MPAs, and 79% of threatened species have less than 1%. We also find the WDPA contains major gaps in take-status reporting, only one third of countries (34%) report take-status of any MPAs to the WDPA, further limiting estimates of meaningful protection. These results highlight the implementation gap between global coverage targets and biodiversity outcomes, reinforcing the need for species-focused protection.
Morgan, M. C.; Hopkins, C. R.; Forster, R.; Gomez, A.
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Global biodiversity is declining at an unprecedented rate due to rapid environmental change and increasing human pressures. Ongoing urban expansion fragments natural systems, while urban design increasingly seeks to mitigate these impacts through the integration of blue-green infrastructure. Effective biodiversity monitoring is therefore essential to evaluate ecological conditions within these novel socio-ecological systems. Although urban biodiversity monitoring is challenged by its high landscape heterogeneity, dense human populations provide opportunities for large-scale data collection through public participation in citizen science. Using data from 25 City Nature Challenge (CNC) projects across the United Kingdom (2020-2025), we assessed the effects of the four-day bioblitz on species inventories, participation in biological recording, and spatial patterns of recording effort. CNC events doubled public participation in iNaturalist recording relative to baseline activity, leading to the documentation of numerous previously unrecorded species through increased observer effort and broader use of urban blue-green spaces. These results show that CNC events enhance urban biodiversity datasets by increasing the number of observers and reducing spatial and observer biases, providing a cost-effective tool for enriching urban biodiversity data. In addition to generating ecological data, CNC events could have public health benefits through increased exposure to urban blue-green spaces.
Swift, M. E.; Songhurst, A.; McCullogh, G.; Beytell, P.; Naidoo, R.
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Reliable freshwater access drives terrestrial wildlife movements and habitat use globally. The small, rain-fed seasonal pools critical for dryland wildlife persistence are vulnerable to rising temperatures and unstable precipitation regimes projected under climate change. In southern Africa, which is expected to warm rapidly by 2100, the drying and disappearance of surface water may cause a breakdown in seasonal migrations of large, area-sensitive, and water-dependent wildlife species. Furthermore, the disappearance of ephemeral water may concentrate wildlife around remaining surface water, increasing resource competition and human-wildlife conflict. An accurate understanding of the dynamics and drivers of seasonal surface water will therefore be critical to wildlife and human health as climate change intensifies. Here, we present a framework and empirical analysis of fine-scale surface water mapping in the 520,000km2 Kavango Zambezi Transfrontier Conservation Area (KAZA), the worlds largest terrestrial conservation area. From 2019-2025, we implemented Otsu thresholding on median Automated Water Extraction Index imagery from 10m Sentinel-2 MSI, leveraging high wet season contrast between vegetation and water as a dry season positive mask. We created >35 quasi-monthly KAZA-wide Ephemeral Surface Water (ESW) rasters (mean classification accuracy 87%, compared to 50% accuracy for existing water products), and found wet season precipitation drivers of non-riparian water fill levels did not extend into the dry season. Then, using GPS data from 27 African savanna elephants (Loxodonta africana), which typically visit water every 48 hours, we compared elephant water visitation rates based on ESW to existing 30m Global Surface Water (GSW) maps. Models using ESW estimated 99% of elephant data came within a 48-hour window, compared to 42% for GSW, suggesting that ESW is a better proxy for actual wildlife water use in animal movement modeling. As aridification threatens to diminish surface water resources, we must model the drivers of wildlife movements at the scale of wildlife needs. With ESW, we provide fine scale accessible surface water data and a straightforward coding architecture for applications beyond KAZA.
Stukel, M. R.; Landry, M. R.; Decima, M.; Fender, C. K.; Kranz, S. A.; Laiz-Carrion, R. L.; Malca, E.; QUINTANILLA, J. M.; Selph, K. E.; Swalethorp, R.; Yingling, N.
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Using linear inverse ecosystem modeling as a data assimilation tool, we compare spawning grounds of Atlantic and Southern Bluefin Tuna (ABT and SBT, respectively) based on results from field campaigns in the Gulf of Mexico (GoM) and eastern Indian Ocean off northwest Australia (Argo Basin). Both regions are warm, stratified, low-nutrient waters dominated by cyanobacteria (Prochlorococcus). Despite these similarities, the Argo Basin is more productive, with [~]1.5X higher net primary production and nearly 2X higher production of top trophic levels in the model (tuna larvae, planktivorous fish, and predatory gelatinous zooplankton). Higher primary production in the Argo Basin is mainly driven by higher N2 fixation and storm mixing of new nutrients in the upper and lower euphotic zone, respectively. Increased ecosystem efficiency (secondary production of top trophic levels / primary production) results from differences in plankton food web organization. In the GoM, protistan zooplankton are the direct consumers of nearly all phytoplankton production. In contrast, higher rates of herbivory by crustaceans feeding on nanophytoplankton combines with a higher impact of appendicularians on cyanobacteria to convert plankton production into larval tuna prey more efficiently in the Argo Basin. Despite similarities in the proportions of phytoplankton production mediated by cyanobacteria and other picoplankton in both systems, food web pathways to larval tuna and other planktivorous fish are substantially shorter in the Argo Basin. Our results highlight the impact of distinct zooplankton ecological niches on ecosystem efficiency and suggest a need for better inclusion of plankton food-web structure in models simulating climate impacts on fisheries production. HIGHLIGHTSO_LIDeveloped food web models of tuna spawning habitat (Indian Ocean & Gulf of Mexico) C_LIO_LISpawning habitats in the Argo Basin and Gulf of Mexico (GoM) are both oligotrophic C_LIO_LIArgo Basin had higher net primary production in part as a result of nitrogen fixation C_LIO_LIArgo Basin had higher rates of direct herbivory by metazoan zooplankton C_LIO_LIThis resulted in greater ecosystem efficiency in the Argo Basin. C_LI
ROY, A.; Delord, K. C.; BARBRAUD, C.; TERRAY, P.
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Wind has a strong influence on the flight characteristics, movements, energetics, demography, life-history traits and biogeography of flying animals. With climate change affecting atmospheric circulation patterns at different time scales, understanding the links between wind and animal movements is crucial for predicting its impact on flying biodiversity. Most studies on the relationship between wind and seabird movements have, however, focused on local scales, exploring birds perceptive sensitivity to local wind. In this study, we examine low-level wind pattern oscillations in the Southern Indian Ocean at multiple time scales to explain the local- to large-scale movements of the Amsterdam albatross. Adult individuals exhibited smooth trajectories, strongly correlated with seasonal, intra-seasonal or interannual wind oscillations. Conversely, younger individuals displayed more erratic and exploratory movements, often being swept away by eastward moving low-pressure systems at a synoptic time scale. Our results suggest that Amsterdam albatrosses can learn and adapt to the annual and monthly low-level wind climatology and interannual variability of the Southern Indian Ocean. This also highlights the importance of investigating seabird movements in relation to broader-scale wind patterns to support their conservation in a changing climate due to human activities. A robust assessment of regional circulation response to climate change for upcoming decades could help project the impact of climate change on seabird movements and mitigate its effects.
Skalon, E.; Goodbody-Gringley, G.; Nativ, H.; Einbinder, S.; Vitienes, I.; Zaslansky, P.; Chequer, A.; Mass, T.
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Mesophotic coral ecosystems have been proposed as climate refugia for shallow reefs, yet the capacity of mesophotic corals to persist across depth gradients remains unresolved. We conducted a long-term reciprocal transplantation of the Caribbean coral Porites astreoides between shallow (10 m) and mesophotic (40 m) reefs to assess physiological, skeletal, and transcriptomic plasticity. Depth, rather than season, was the primary driver of coral performance. Shallow colonies exhibited higher metabolic activity and calcification, whereas mesophotic colonies showed reduced protein content, slower skeletal extension, and elevated expression of skeletal organic matrix genes. Transplant responses were asymmetric: shallow-to-deep corals acclimated through coordinated physiological and transcriptional adjustments, while deep-to-shallow transplants experienced mortality and limited transcriptional reprogramming. Moderate genetic connectivity across depths suggests that performance differences arise primarily from phenotypic plasticity rather than fixed genetic divergence. Our findings indicate that shallow populations harbor greater acclimatory capacity, whereas mesophotic corals show constrained upward resilience, challenging the generality of deep reefs as refugia under rapid environmental change. TeaserAsymmetric plasticity limits the capacity of mesophotic corals to rejuvenate shallow reefs under climate change.
Sanchez, S. R.; Schneider, C.; Fangue, N. A.; Lusardi, R. A.; Rypel, A. L.
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Catch inequality--the disproportionate distribution of catch across anglers-- is a fundamental but overlooked driver of recreational fisheries dynamics. Here, we use 11 years (2012-2022) of compulsory angler report cards to characterize long-term catch dynamics in the specialized recreational steelhead (Oncorhynchus mykiss) fishery in California, U.S.A. Spatialized catch data reveal the fishery is principally supported by wild fish, despite evidence of widespread hatchery straying. California steelhead appear to represent the most catch-unequal recreational fishery studied yet, exhibiting a statewide Gini coefficient of 0.81. Across basins, inequality varies substantially but remains relatively stable over time and flow conditions; high inequality is primarily driven by significant proportions of zero-catch anglers. We find the relationship between sample size and inequality measures is especially influential in fisheries data. Hence, we develop a three-prong approach for identifying minimal sample sizes required for robust Gini estimation. Across basins and years, an average minimum of 77 report cards were required for the present fishery. Collectively, these findings demonstrate the necessity of considering catch inequality in fisheries management, particularly when utilizing angler data. Graphical AbstractN.a.
Gutierrez-Preciado, A.; Struillou, A.; Liang, L.; Iniesto, M.; Deschamps, P.; Eme, L.; Zivanovic, Y.; Lopez-Garcia, J. M.; Benzerara, K.; Moreira, D.; Lopez-Garcia, P.
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Eukaryotes originated from the symbiosis of an Asgard archaeon, the alphaproteobacterial ancestor of mitochondria, and possibly additional bacterial contributions. This transition occurred in redox-transition environments such as microbial mats or shallow sediments [~]2 billion years ago, when atmospheric oxygen was far lower than today. We investigated Asgard-enriched microbial mats from the low-oxygen, sulfidic Catherine volcano lake (Afar region, Ethiopia), mimicking early Proterozoic conditions. 16S rRNA gene metabarcoding, metagenomics, and metagenome-assembled genome analyses across redox-stratified layers of in situ and mesocosm-maintained mats revealed that Asgardarchaeota thrived in the sulfate-reduction zone, mainly co-occurring with Desulfurobacterota-Myxococcota, among others. Lokiarchaeia and Thorarchaeia preferred anoxic layers. Within Heimdallarchaeia, Heimdallarchaeales were enriched in upper layers, correlating with oxygen-tolerant hydrogenase and sulfate-reduction genes, and Hodarchaeales, in anoxic layers, correlating with methanogenesis. Although reactive-oxygen-species defense mechanisms were widespread, Asgardarchaeota lacked aerobic respiration. These results support the idea that Asgard archaea engaged primarily in syntrophic interactions with sulfate-reducers under early-Earth-like conditions.
Wilbourn, E. K.; Curtis, D.; Kolla, H.; Rai, P.; Lane, P.; McGowen, J.; Lane, T. W.; Poorey, K.
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For sustainable algal biomass cultivation, we need substantial improvement in annualized productivity by reducing the frequency of crop failure and improved growth in open raceway pond systems. In this study, high-performing strains were identified and optimized for biomass productivity. We utilized next-generation sequencing methods to quantify the ecological features of open raceway systems cultivated at in Arizona. We utilized data from several months of cultivation runs to construct a rich time-series of the ecology dynamics using amplicon sequencing and used custom anomaly detection, "PondSentry", for the early prediction of pond crashes. PondSentry uses tensor decomposition of higher-order joint moments to detect incipient anomalies in multivariate data and displays significant improvements from standard knowledge-based anomaly detection methods. The PondSentry strategy identifies signs of deteriorating pond health at an average of three days before an actual crash event, with rank order of the ecological features plausible for crop failures driven by organisms such as Amoeboaphelidium occidentale FD01. These findings are independently confirmed with PCR and microscopy studies at an Arizona cultivation site. PondSentrys time-series-based anomaly detection of crashes provides a suitable monitoring strategy for eukaryotic crash agents in unialgal culture. The early warnings can be used to time interventions or harvests to prevent biomass loss. The PondSentry strategy strengthens the role of data science and data-driven methods in algal cultivation and can increase the feasibility of algal-biomass based products.