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Environmental variation commonly drives functional trait diversity within species, among species, and across communities. Climate and shared evolutionary history can both influence trait–environment relationships. We studied variation in plant functional traits among closely related Costus species occurring across environmental gradients, the extent to which this variation occurs within single species, and how that variation may be influenced by shared evolutionary history. We measured leaf, aboveground stem, rhizome, and fine root traits of 17 species of Costus in eight sites in Costa Rica and Panama, which varied in elevation, temperature, and precipitation. We then assessed the relationships among traits and environmental variables and estimated the phylogenetic signal of the traits. We observed significant relationships between functional traits and climate. Stomatal conductance decreased, but stem density and rhizome dry matter content increased with decreasing mean annual temperature and precipitation seasonality in both cross-species and single-species analyses. This suggests that herbaceous species have a similar trade-off between plant hydraulic efficiency and safety as found in woody plants. Mean annual temperature was a stronger driver of trait variation than mean annual precipitation. We also found phylogenetic signal in leaf and stem structural traits (i.e., closely related species are more similar than distantly related species), but not in physiological or belowground traits. Our results demonstrate significant trait variation within and among species of Costus, a widespread understory and herbaceous genus in the tropics, which is driven by both climate and shared evolutionary history.

Cacao and chocolate production is a global industry worth around $133 billion. Full sun cultivation is a modern approach aimed at increasing yields. We evaluated six cacao clones (PS 1319, CCN 10, CCN 51, PH 16, SJ 02, and CP 49) grown under full sun conditions to assess their leaf physiology, leaf structure, yield, and yield components. Leaf physiology was measured through seven gas exchange parameters, while leaf structure was analyzed using eight measurements. For fruit and seed, we evaluated seven yield components. The clones showed differences in gas exchange. Clones PH 16 and PS 1319 had higher net photosynthetic rates per unit of leaf area (A), transpiration rates, and lower leaf internal CO2 concentrations. These A high values suggest the clones are well-acclimatized to full sun cultivation. Water availability, nutrient supply, and appropriate plant architecture also contributed to this acclimatization. Under high light intensity, the potential quantum yield of photosystem II indicated no photoinhibition, and adaptations in the photosynthetic apparatus were observed, such as lower pigment concentration in clone PH 16. Clones differed in specific leaf area (SLA) and stomatal density (SD). CCN 51 had a higher SLA, while SJ 02 had a higher SD. A significant negative correlation (-0.89) was found between dry bean yield and leaf-to-air water vapor pressure deficit (VpdL), suggesting that VpdL is a crucial parameter for selecting high-performance clones for fertigated full sun cultivation. Yields ranged from 1,220 kg/ha (CCN 10) to 2,900 kg/ha (CCN 51). Full sun cacao farms have high yield potential due to a combination of cloning, management practices, and adequate water and nutrient availability. [ABSTRACT FROM AUTHOR]

Ultraviolet radiation (UV) represents a significant abiotic stress, affecting green plants. Phenolic compounds have been suggested as components involved in plant photoprotective adaptation. We used a unique combination of experimental (LED lighting and leaf tagging) and analytical (unbiased, or untargeted, metabolomics) approaches to study the effects of high (approximating mid-summer) and low (approximating winter) levels of UVA on the expression of phenolic compounds. These consisted of river red gum (Eucalyptus camaldulensis ssp. camaldulensis) of five provenances. The geographically separated provenances used in our study spanned the lowest and highest latitudes of the range of this subspecies. The concentrations of gallotannins and ellagitannins (i.e., hydrolysable tannins) increased most under high levels of UVA, but responses only differed slightly among provenances. The most substantial changes in the composition of phenolic compounds were associated with leaf age. Overall, 3-month-old (herein, termed 'young') leaves had substantially different phenolic compositions to 6- and 12-month-old ('old') leaves. Hydrolysable tannins were more abundant in young leaves, whereas pedunculagin, catechin, and kaempferol galloyl glucoses were more abundant in old leaves. High levels of UVA altered the expression of phenolic compounds, but our experimental saplings were unlikely to experience photoinhibition because they were not exposed to high levels of light and low temperatures, nor were they nitrogen-limited. We expect that changes in phenolic compounds would have been more pronounced if we had induced photoinhibition. [ABSTRACT FROM AUTHOR]

Introduction: Marine hydrothermal systems (MHS) are considered extreme environments due to their unique physicochemical conditions, which are challenging for most organisms. This study investigates the microbial communities in three MHS sites in Baja California Sur, Mexico. Methods: Sediment samples were collected in two seasons of the year: rainy and dry season. Bacterial DNA was extracted, the V3-V4 regions of the 16S rRNA gene were amplified. Results and discussion: The analysis of microbial community structure and composition revealed that species richness and diversity were higher at control sites (not influenced by hydrothermal conditions). Samples from the MHS showed temporal variation in richness, as measured by the Chao1 index. Alphaproteobacteria and Gammaproteobacteria were the dominant classes. No significant differences in community structure were found between the seasons or between the control and MHS sites. However, the analysis did reveal differences in community structure among the three hydrothermal locations: Burro, Santispac, and Agua Caliente. The presence of Gammaproteobacteria , Alphaproteobacteria , Deltaproteobacteria , and Betaproteobacteria highlights their key roles in primary production within shallow hydrothermal systems, these microbial communities demonstrate their capacity to colonize diverse substrates. This study enhances the microbiological understanding of hydrothermal environments in Baja California Sur, and molecular analysis of unculturable microbes could provide further insights into their physiology and ecological roles in shallow hydrothermal systems. [ABSTRACT FROM AUTHOR]

The ecophysiological and ecohydrological impacts of climate change and progressively increasing atmospheric carbon dioxide (CO2) concentration on agroecosystems are not well understood compared to the forest ecosystems. In this study, we utilized the presence of old apple and pear trees in the alpine valleys of Northern Italy (maintained for cultural heritage purposes) to investigate climate-scale physiological responses. We developed long-term tree-ring stable isotopic records (δ13C and δ18O) from apple (1976-2021) and pear trees (1943-2021). This allowed the reconstruction of key ecophysiological processes like the variations in intrinsic water use efficiency (i WUE), and we investigated how these trees responded to climate and CO2 changes over decades. Results showed a slight declining trend in carbon discrimination (Δ 13C) while intercellular CO2 concentration (C i) for both species has been increasing since the late 1980s. Concurrently both species exhibited a rising trend in i WUE, with apple trees demonstrating higher efficiency, which appears to be primarily driven by the CO2-fertilization effect. The concomitant trends in tree-ring δ18O suggested a relatively stable local hydroclimate during the study period with some species-specific responses. Analyses further revealed that minimum growing season temperature, not precipitation was the most significant factor influencing the rise in i WUE alongside with CO2 fertilization effect. Analyses of species' δ13C coupled with their respective δ18O confirmed that the rise in i WUE was due to increased carbon assimilation rather than a decline in evapotranspiration. Moreover, coupled δ13C–δ18O analyses suggested increasing trends in carbon assimilation, with apple trees showing higher inter-decadal variations. These long-term records provide a unique opportunity to test and calibrate how these systems respond to recent and anticipated climate change. [ABSTRACT FROM AUTHOR]

Summary: Harnessing the plant microbiome through plant genetics is of increasing interest to those seeking to improve plant nutrition and health. While genome‐wide association studies (GWAS) have been conducted to identify plant genes driving the plant microbiome, more multidisciplinary studies are required to assess the relationships among plant genetics, plant microbiome and plant fitness.Using a metabarcoding approach, we characterized the rhizosphere bacterial communities of a core collection of 155 Medicago truncatula genotypes along with the plant phenotype and investigated the plant genetic effects through GWAS.The different genotypes within the M. truncatula core collection showed contrasting growth and nutritional strategies but few loci were associated with these ecophysiological traits. To go further, we described its associated rhizosphere bacterial communities, dominated by Proteobacteria, Actinobacteria and Bacteroidetes, and defined a core rhizosphere bacterial community. Next, the occurrences of bacterial candidates predicting plant ecophysiological traits of interest were identified using random forest analyses. Some of them were heritable and plant loci were identified, pinpointing genes related to response to hormone stimulus, systemic acquired resistance, response to stress, nutrient starvation or transport, and root development.Together, these results suggest that plant genetics can affect plant growth and nutritional strategies by harnessing keystone bacteria in a well‐connected interaction network. [ABSTRACT FROM AUTHOR]

Summary: Trait‐based ecology has become a popular phrase. But all species have traits, and their contributions to ecological processes are governed by those traits. So then, is not all ecology trait‐based? Actually, there do exist areas of ecology that are consciously trait‐free, such as neutral theory and species abundance distributions. But much of ecology could be considered actually or potentially trait‐based. A spectrum is described, from trait‐free through trait‐implicit and trait‐explicit to trait‐centric. Trait‐centric ecology includes positioning ecological strategies along trait dimensions, with a view to inferring commonalities and to generalizing from species studied in more detail. Trait‐explicit includes physiological and functional ecology, and areas of community ecology and ecosystem function that invoke traits. Trait‐implicit topics are those where it is important that species are different, but formulations did not initially characterize the differences via traits. Subsequently, strands within these trait‐implicit topics have often moved towards making use of species traits, so the boundary with trait‐explicit is permeable. Trait‐based ecology is productive because of the dialogue between understanding processes in detail, via traits that relate most closely, and generalizing across many species, via traits that can be compared widely. An enduring key question for trait‐based ecology is which traits for which processes. [ABSTRACT FROM AUTHOR]

Electronic cigarettes (e-cigs) fundamentally differ from tobacco cigarettes in their generation of liquid-based aerosols. Investigating how e-cig aerosols behave when inhaled into the dynamic environment of the lung is important for understanding vaping-related exposure and toxicity. A ventilated artificial lung model was developed to replicate the ventilatory and environmental features of the human lung and study their impact on the characteristics of inhaled e-cig aerosols from simulated vaping scenarios. Compared to static conditions, normal breathing decreased peak particle number concentrations (PNCs) and area under the curve (AUC) by 40% and 70%, respectively, and increased particle decay rates fourfold. However, even with ventilation, intrapulmonary PNC levels exceeded 2 × 106 particles/mL in a 4-puff vaping session. Both respiratory rate and tidal volume modulated e-cig aerosol exposure in a manner inversely proportional to minute ventilation. The modeled lung environment (37 °C, 88% relative humidity) also significantly altered particle size distributions by facilitating aerosol transformations such as hygroscopic growth, which further impacted e-cig aerosol exposure and particle removal. This work highlights the dynamic nature of intrapulmonary exposures and underscores the need to account for lung physiology and environmental factors when assessing inhaled e-cig aerosols. [ABSTRACT FROM AUTHOR]

Studies of in situ plant response and adaptation to complex environmental stresses, are crucial for understanding the mechanisms of formation and functioning of ecosystems of anthropogenically transformed habitats. We study short- and long-term responses of photosynthetic apparatus (PSA) and anti-oxidant capacity to complex abiotic stresses of common plants Calamagrostis epigejos and Solidago gigantea in semi-natural (C) and heavy metal contaminated habitats (LZ). We found significant differences in leaf pigment content between both plant species growing on LZ plots and their respective C populations. The average values of leaf chlorophyll indexes were 27% lower in the LZ populations of both species and significantly lower in Sg plants in comparison to Ce ones. The average values of the anthocyanin index in CeLZ and SgLZ populations were significantly higher (by 18%) than in their respective controls. In both Ce and Sg plants occurring on LZ plots, the average leaf flavonol indexes were higher than on their controls by 31% and 15% and this index was significantly higher in SgLZ population than CeLZ and CeC plants (by 34% and 54%, respectively). Both Ce and Sg populations growing on LZ plots showed significantly lower photosynthetic rate (A), transpiration rate (E) and stomatal conductance (gs) in comparison to controls. On the other hand, a significantly higher photosynthetic rate was detected in SgLZ than in CeLZ populations. The catalase activities were significantly higher than recorded in Sg than in Ce tissues, irrespective of the plot type. They were also higher in LZ populations than those in controls for both species. Moreover, the H2O2 content in Sg tissues was significantly higher than those in Ce. Hydrogen peroxide content in CeLZ and SgLZ were respectively 39% (non-significant) and 57% higher, compared to their controls. The reverse pattern was found in the case of MDA, whose concentration was significantly higher in the leaves of Ce population compared to the control population. The average MDA concentration in CeLZ populations was 17% higher than in the CeC. In the case of Sg no significant differences were found. Mechanisms of plant species adaptation to industrial areas are crucial for species selection and planning effective reclamation of them. The analysis of chlorophyll fluorescence induction curves as well as well as the results of JIP test revealed the decreased of Fj value despite positive ΔK–band in SgLZ and CeLZ plants suggesting the increased rate of electron transfer from QA to QB at the acceptor side of PSII, thus a high quantity of P680+ and/or effective quenching by exogenous molecules. The increase in the I–P part of the induction curve typically attributed to the reduction of electron transporters (ferredoxin, intermediary acceptors, and NADP) of the PSI acceptor side was observed in both SgC and SgLZ but not in CeLZ populations. These changes demonstrate species-specific effects on electron transport during the light phase of photosynthesis under complex environmental stress. Our results show that Sg and Ce individuals developed a range of structural and functional adaptations to protect PSA against complex environmental stresses (possible combination of heavy metals, water deficiency, temperature, nutrient deficiency and salinity). Both species from LZ plots could tolerate high levels of Cd, Zn and Pb in leaf tissues. Therefore they can be potential candidates for use in phytoremediation of HM contaminated areas. However, further long-term field and experimental research on plant traits response and adaptation to complex environmental stresses on industrial habitats are needed. [ABSTRACT FROM AUTHOR]

Climate change threatens biodiversity by compromising the ability to balance energy and water, influencing animal behaviour, species interactions, distribution and ultimately survival. Predicting climate change effects on thermal physiology is complicated by interspecific variation in thermal tolerance limits, thermoregulatory behaviour and heterogenous thermal landscapes. We develop an approach for assessing thermal vulnerability for endotherms by incorporating behaviour and microsite data into a biophysical model. We parameterised the model using species‐specific functional traits and published behavioural data on hotter (maximum daily temperature, Tmax > 35°C) and cooler days (Tmax < 35°C). Incorporating continuous time‐activity focal observations of behaviour into the biophysical approach reveals that the three insectivorous birds modelled here are at greater risk of lethal hyperthermia than dehydration under climate change, contrary to previous thermal risk assessments. Southern yellow‐billed hornbills Tockus leucomelas, southern pied babblers Turdoides bicolor and southern fiscals Lanius collaris are predicted to experience a risk of lethal hyperthermia on ~ 24, 65 and 40 more days year−1, respectively, in 2100 relative to current conditions. Maintaining water balance may also become increasingly challenging. Babblers are predicted to experience a 57% increase (to ~186 days year−1) in exposure to conditions associated with net negative 24 h water balance in the absence of drinking, with ~ 86 of those days associated with a risk of lethal dehydration. Hornbills and fiscals are predicted to experience ~ 84 and 100 days year−1, respectively, associated with net negative 24 h water balance, with ≤ 20 of those days associated with a risk of lethal dehydration. Integrating continuous time‐activity focal data is vital to understand and predict thermal challenges animals likely experience. We provide a comprehensive thermal risk assessment and emphasise the importance of thermoregulatory and drinking behaviour for endotherm persistence in coming decades. [ABSTRACT FROM AUTHOR]

Changes in climate and land management over the last half‐century have favoured woody plants native to grasslands and led to the rapid expansion of woody species. Despite this being a global phenomenon, it is unclear why some woody species have rapidly expanded while others have not. We assessed whether the most abundant woody encroaching species in tallgrass prairie have common growth forms and physiology or unique traits that differentiate their resource‐use strategies. We characterized the abundance, above‐ground carbon allocation, and leaf‐level physiological and structural traits of seven woody encroaching species in tallgrass prairie that span an order of magnitude in abundance. To identify species‐specific increases in abundance, we used a 34‐year species composition dataset at Konza Prairie Biological Station (Central Great Plains, USA). We then compared biomass allocation and leaf‐level traits to determine differences in carbon and water use strategies among species. While all focal species increased in abundance over time, encroachment in this system is primarily driven by three species: Cornus drummondii, Prunus americana and Rhus glabra. The most dominant species, Cornus drummondii, had the most extreme values for several traits, including the lowest leaf:stem mass ratios, lowest photosynthetic capacity and highest turgor loss point. Two of the most abundant species, Cornus drummondii and Rhus glabra, had opposing growth forms and resource‐use strategies. These species had significantly different above‐ground carbon allocation, leaf‐level drought tolerance and photosynthetic capacity. There were surprisingly few interspecific differences in specific leaf area and leaf dry matter content, suggesting these traits were poor predictors of species‐level encroachment. Synthesis. Woody encroaching species in tallgrass prairie encompass a spectrum of growth forms and leaf physiology. Two of the most abundant woody species fell at opposite ends of this spectrum. Our results suggest niche differences among a community of woody species facilitate the rapid encroachment by a few species. This study shows that woody encroaching species do not conform to a ‘one‐size‐fits‐all’ strategy, and a diversity of growth forms and physiological strategies may make it more challenging to reach management goals that aim to conserve or restore grassland communities. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have been detected in various aquatic environments and negatively affect organisms, including marine luminous bacteria. This study investigated the differences in bioluminescence patterns, cell viability, and biofilm formation of Photobacterium leiognathi strains (LB01 and LB09) when exposed to various concentrations of ground microplastics (GMPs; 0.25%, 0.50%, 1%, or 2% [w/v] per mL) at 22°C or 30°C for 3.1 days (75 h) and 7 days. The strains exhibited heterogenous responses, including variable bioluminescence patterns, cell viability, and biofilm formation, due to the GMPs having effects such as hormesis and bioluminescence quenching. Moreover, the bioluminescence and cell viability differed between the two strains, possibly involving distinct cellular mechanisms, suggesting that GMPs affect factors that influence quorum sensing. Furthermore, the biofilm formation of LB01 and LB09 was observed following exposure to GMPs. Both strains showed increased biofilm formation at higher GMP concentrations (1% and 2%) after 3.1 days at 30°C and 22°C. However, in the 7-day experiment, LB01 significantly (p < 0.05) increased biofilms at 22°C, while LB09 significantly (p < 0.05) produced biofilms at 30°C. These findings highlight the strain-specific responses of Phb. leiognathi to MP pollutants. Therefore, this study underscores the importance of evaluating MPs as environmental stressors on marine microorganisms and their role in the ecophysiological repercussions of plastic pollution in aquatic environments. [ABSTRACT FROM AUTHOR]

Climate change is a health‐risk and health‐inequity multiplier with excessive heat exposure a direct climate change impact already affecting the health and livelihood of billions globally. Women face greater risks and burdens from climate change impacts. Biological sex may or may not influence an individual's thermoregulatory capacity, heat tolerance or heat susceptibility. However at a population level, sex differences in physiological characteristics (anthropometrics, aerobic capacity, etc.) likely affect thermoregulatory capacity. Still, gender appears to play the most significant role in heat exposure and resulting health impacts. For climate change resilience and adaptation strategies to be effective, public health and occupational guidance/governance must be based on comprehensive and representative evidence. The current dearth of empirical evidence on how excessive heat exposure affects women prohibits this. Environmental and exercise physiology can help address this lack of empirical evidence by adhering to inclusive research guidelines. This paper is based on a symposium presentation given at Physiology 2023 in Harrogate, UK. Using a multi‐year cohort study on industrial agricultural workers (the Adelante Initiative) as a case study, this review discusses the role of environmental and exercise physiology in generating inclusive research and evidence to inform occupational and public health guidance/governance for climate change resilience and adaptation, specifically heat exposure. [ABSTRACT FROM AUTHOR]

Water level is crucial to the growth and development of wetland plants, in order to study the physiological and ecological responses of Pomatogeton crispus under different water levels, in the study, P. crispus were placed under 50 cm (control) and 60–135 cm water levels following a 15 cm gap gradient for 60 days in a simulation experiment. The results showed that: (1) As the water level gradient increased, the plant height, leaf number and biomass of P. crispus showed a trend of increasing and then decreasing. (2) The concentrations of chlorophyll a (Chl-a), chlorophyll b (Chl-b), chlorophyll a + b (Chl a + b) and carotenoids (Car) showed a multi-peak increasing trend with increasing water level, with the maximum values occurring in the 135 cm water level group. (3) The antioxidant enzymes of P. crispus showed a fluctuating upward trend with increasing water level, and the higher the water level the greater the difference within the group, and rooting activity of P. crispus was significantly increased under elevated water level conditions. (4) The P. crispus grows best in the water level range of 105 ∼ 120 cm, and the growth indexes such as the number of leaves and biomass all reach higher values in the water level of 105 ∼ 120 cm, If the water level is too high or too low, it has an effect on the growth and development of P. crispus. [ABSTRACT FROM AUTHOR]

To enhance the plantation performance of Swietenia humilis Zucc., a threatened precious woody species from the dry tropics of Latin America, this study examined its morpho-physiological responses to variations in nutrient and light availability. We established a nursery trial with factorial treatments: three levels of fertilization (4, 6, and 8 g L−1 of substrate using a controlled-release fertilizer, CRF, 18-6-12) and two shade intensities (60% and 40%), alongside a full sun treatment. The field performance of nursery-raised plants was evaluated under two site conditions (with and without mechanical soil preparation) over 48 months. In the nursery, S. humilis exhibited diverse morpho-physiological characteristics influenced by the studied factors, with optimal growth observed at 6 g of the CRF and 40% shade. Mechanical soil preparation significantly improved plant survival, reducing mortality risk by 99.16% and increasing survival probability to nearly 75%. Height growth was also enhanced, being 2.5 times greater in the prepared site compared to that in the unprepared one. S. humilis showed acclimatization in the field, producing new foliage with high chlorophyll content. In conclusion, nursery management and soil site preparation influence the field performance of S. humilis. These findings have practical implications for improving the management of S. humilis in plantations across the dry tropics. [ABSTRACT FROM AUTHOR]

Abstract Soil water deficit (WD) significantly impacts plant survival and crop yields. Many gaps remain in our understanding of the synergistic coordination between molecular and ecophysiological responses delaying substantial drought-induced effects on plant growth. To investigate this synergism in tomato leaves, we combined molecular, ecophysiological, and anatomical methods to examine gene expression patterns and physio-anatomical characteristics during a progressing WD experiment. Four sampling points were selected for transcriptomic analysis based on the key ecophysiological responses of the tomato leaves: 4 and 5 days after WD (d-WD), corresponding to 10% and 90% decrease in leaf stomatal conductance; 8 d-WD, the leaf wilting point; and 10 d-WD, when air embolism blocks 12% of the leaf xylem water transport. At 4 d-WD, upregulated genes were mostly linked to ABA-independent responses, with larger-scale ABA-dependent responses occurring at 5 d-WD. At 8 d-WD, we observed an upregulation of heat shock transcription factors, and two days later (10 d-WD), we found a strong upregulation of oxidative stress transcription factors. Finally, we found that young leaves present a stronger dehydration tolerance than mature leaves at the same drought intensity level, presumably because young leaves upregulate genes related to increased callose deposition resulting in limiting water loss to the phloem, and related to increased cell rigidity by modifying cell wall structures. This combined dataset will serve as a framework for future studies that aim to obtain a more holistic WD plant response at the molecular, ecophysiological and anatomical level.

Societal Impact Statement Globally, the combustion of fossil fuels represents the vast majority of greenhouse gas emissions, and as such, a transition to renewable forms of energy provides the greatest potential for mitigating climate warming. Although solar photovoltaic energy generation is a leading climate solution, these energy facilities have a significant spatial footprint. Naturally, concerns regarding the coexistence of solar development in agriculturally productive and pristine native ecosystems remain. This study offers insight for how plants respond to novel environmental conditions within a solar array and contextualizes results to inform future array siting, design, and management to realize a sustainable solar energy future. Summary Photovoltaic (PV) solar arrays impose dynamic shading regimes and redistribute precipitation to the ecosystems beneath, leading to spatial and temporal heterogeneity in plant growth environments. Although PV are known to alter ecosystem‐level processes in managed and native landscapes, the control of PV‐induced microenvironments on plant ecophysiological responses are largely unexplored. A more robust and mechanistic understanding of how PV microenvironments control plant response will inform management of existing solar arrays and provide insight for future arrays designed to enhance ecosystem services. Here, we evaluated carbon (photosynthetic parameters) and water relations (daily patterns of leaf water potential (ψL) and stomatal conductance (gsw)) in a C3 perennial grass (Bromus inermis) across PV microsites within a 1.6 ha (1.2 MW) array in semiarid Colorado, USA. Light‐saturated photosynthetic rate was surprisingly consistent spatially, not differing between plants growing in near full sun (between PV rows) versus those growing in shadier microsites beneath panels (~28% of full sunlight). Additionally, plants located in microsites receiving only direct sunlight in the morning, when air temperature and vapor pressure deficits (VPD) were low, had greater ψL and gsw than plants receiving direct sunlight primarily in the hotter drier afternoon. Thus, while soil moisture is a primary control of plant productivity in most water‐limited grasslands, we found that VPD was a better predictor of daily patterns of leaf‐level photosynthetic and water relations responses that control aboveground biomass production in a PV array. These findings provide new mechanistic insight for evaluating vegetation management strategies in semiarid PV arrays.

Leaf and wood functional traits of trees are related to growth, reproduction, and survival, but the degree of phylogenetic conservatism in these relationships is largely unknown. In this study, we describe the variability of strategies involving leaf, wood and demographic characteristics for tree genera distributed across the Amazon Region, and quantify phylogenetic signal for the characteristics and their relationships. Leaf and wood traits are aligned with demographic variables along two main axes of variation. The first axis represents the coordination of leaf traits describing resource uptake and use, wood density, seed mass, and survival. The second axis represents the coordination between size and growth. Both axes show strong phylogenetic signal, suggesting a constrained evolution influenced by ancestral values, yet the second axis also has an additional, substantial portion of its variation that is driven by functional correlations unrelated to phylogeny, suggesting simultaneously higher evolutionary lability and coordination. Synthesis. Our results suggest that life history strategies of tropical trees are generally phylogenetically conserved, but that tree lineages may have some capability of responding to environmental changes by modulating their growth and size. Overall, we provide the largest‐scale synopsis of functional characteristics of Amazonian trees, showing substantial nuance in the evolutionary patterns of individual characteristics and their relationships. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Soil water deficit (WD) significantly impacts plant survival and crop yields. Many gaps remain in our understanding of the synergistic coordination between molecular and ecophysiological responses delaying substantial drought-induced effects on plant growth. To investigate this synergism in tomato leaves, we combined molecular, ecophysiological, and anatomical methods to examine gene expression patterns and physio-anatomical characteristics during a progressing WD experiment. Four sampling points were selected for transcriptomic analysis based on the key ecophysiological responses of the tomato leaves: 4 and 5 days after WD (d-WD), corresponding to 10% and 90% decrease in leaf stomatal conductance; 8 d-WD, the leaf wilting point; and 10 d-WD, when air embolism blocks 12% of the leaf xylem water transport. At 4 d-WD, upregulated genes were mostly linked to ABA-independent responses, with larger-scale ABA-dependent responses occurring at 5 d-WD. At 8 d-WD, we observed an upregulation of heat shock transcription factors, and two days later (10 d-WD), we found a strong upregulation of oxidative stress transcription factors. Finally, we found that young leaves present a stronger dehydration tolerance than mature leaves at the same drought intensity level, presumably because young leaves upregulate genes related to increased callose deposition resulting in limiting water loss to the phloem, and related to increased cell rigidity by modifying cell wall structures. This combined dataset will serve as a framework for future studies that aim to obtain a more holistic WD plant response at the molecular, ecophysiological and anatomical level. [ABSTRACT FROM AUTHOR]

Coastal fog occurs along many of the world's west coast continental environments. It is particularly consequential during summer when an increased frequency of fog co-occurs with the seasonal dryness characteristic of most west coast climate systems, for example, in the Pacific coast of North and South America, the southwestern African coast, and southern coastal Europe. Understanding coastal fog formation and effects has consequences for many disciplines, including the physical (e.g., atmospheric science, oceanography), biological (e.g., biogeography, ecophysiology), and socio-ecological realms (e.g., Indigenous cultural knowledge, public safety, economics). Although research practices differ across disciplines, they share many of the challenges needed to advance fog science. For example, coastal fog remains difficult to reliably monitor when, where, and why it occurs, which adds difficulty to understanding fog's effects on all facets of the integrated coastal system. These shared challenges provide ripe opportunities for interdisciplinary collaboration, a template with past success in advancing fog-related science that can continue to have success in the future. In this perspectives review, we summarize the current status and frontiers of fog-related science from multiple disciplines, leveraging examples primarily drawn from the Pacific Northwest coastal region of the United States to show how interdisciplinary collaboration is needed to continue to advance our collective understanding of coastal fog formation and effects on west coast environments. [ABSTRACT FROM AUTHOR]

Background: Light is a key environmental regulator of physiology and behaviour. Mistimed or insufficient light disrupts circadian rhythms and is associated with impaired health and well-being across mammals. Appropriate lighting is therefore crucial for indoor housed mammals. Light is commonly measured in lux. However, this employs a spectral weighting function for human luminance and is not suitable for 'non-visual' effects of light or use across species. In humans, a photoreceptor-specific (α-opic) metrology system has been proposed as a more appropriate way of measuring light. Results: Here we establish technology to allow this α-opic measurement approach to be readily extended across mammalian species, accounting for differences in photoreceptor types, photopigment spectral sensitivities, and eye anatomy. We develop a high-throughput method to derive spectral sensitivities for recombinantly expressed mammalian opsins and use it to establish the spectral sensitivity of melanopsin from 13 non-human mammals. We further address the need for simple measurement strategies for species-specific α-opic measures by developing an accessible online toolbox for calculating these units and validating an open hardware multichannel light sensor for 'point and click' measurement. We finally demonstrate that species-specific α-opic measurements are superior to photopic lux as predictors of physiological responses to light in mice and allow ecologically relevant comparisons of photosensitivity between species. Conclusions: Our study presents methods for measuring light in species-specific α-opic units that are superior to the existing unit of photopic lux and holds the promise of improvements to the health and welfare of animals, scientific research reproducibility, agricultural productivity, and energy usage. [ABSTRACT FROM AUTHOR]

Exploring the evolutionary dynamics of lysozymes is critical for advancing our knowledge of adaptations in immune and digestive systems. Here, we characterize the distribution of a unique class of lysozymes known as g-type, which hydrolyze key components of bacterial cell walls. Notably, ctenophores, and choanoflagellates (the sister group of Metazoa), lack g-type lysozymes. We reveal a mosaic distribution of these genes, particularly within lophotrochozoans/spiralians, suggesting the horizontal gene transfer events from predatory myxobacteria played a role in their acquisition, enabling specialized dietary and defensive adaptations. We further identify two major groups of g-type lysozymes based on their widespread distribution in gastropods. Despite their sequence diversity, these lysozymes maintain conserved structural integrity that is crucial for enzymatic activity, underscoring independent evolutionary pathways where g-type lysozymes have developed functionalities typically associated with different lysozyme types in other species. Specifically, using Aplysia californica as a reference species, we identified three distinct g-type lysozyme genes: two are expressed in organs linked to both feeding and defense, and the third exhibits broader distribution, likely associated with immune functions. These findings advance our understanding of the evolutionary dynamics shaping the recruitment and mosaic functional diversification of these enzymes across metazoans, offering new insights into ecological physiology and physiological evolution as emerging fields. [ABSTRACT FROM AUTHOR]

Primary production in the Southern Ocean is strongly influenced by the availability of light and iron (Fe). To examine the response of two distinct natural Antarctic phytoplankton communities (diatom vs. flagellates) to increasing light and Fe availability, we conducted two shipboard incubation experiments during late summer and exposed each community to increasing light intensities (30, 80, and 150 µmol photons m−2 s−1) with or without Fe amendment. Our results show clearly that both communities were Fe-limited since Fe addition resulted in higher particulate organic carbon (POC) production rates. The magnitude of the Fe-dependent increase in POC production, however, varied between the two stations being higher in the diatom-dominated community relative to the flagellate-dominated community. This differential response to increasing Fe supply could be attributed to the higher Fe requirement of the flagellate-dominated assemblage relative to the diatom-dominated assemblage. Irrespective of Fe availability, light also strongly stimulated the POC production of both communities between low and medium light supply (30 versus 80 µmol photons m−2 s−1), indicating that both assemblages were light-limited in situ. However, since POC production of both communities did not increase further at the highest light intensity (150 µmol photons m−2 s−1) even under high Fe supply, this suggests that light supply was saturated or that other conditions must be fulfilled (e.g., availability of trace metals other than Fe) in order for the communities to benefit from the higher light and Fe conditions. [ABSTRACT FROM AUTHOR]

Altricial songbirds transform themselves from naked poikilotherms to fully feathered endothermic homeotherms over a matter of days from hatching to fledging. The ontogeny of endothermy is a developmental milestone for birds that not only face warmer average temperatures, but also increasingly frequent cold snaps and extreme weather. The timing of development of endothermy has been studied in altricial birds for over half a century. However, the determinants and constraints of the onset of endothermy are not yet fully understood. We experimentally investigated whether brood size influences the ontogeny of endothermic heat production in 4–8 day‐old nestling blue tits Cyanistes caeruleus in southern Sweden. The thermogenic response to a cooling challenge (15°C) increased with age overall. We found that 8‐day‐old nestlings from reduced broods had a slightly increased capacity for endothermic heat production compared to enlarged broods. This difference cannot be explained by body mass because this trait did not differ between brood size categories. Although a metabolic response was present in most nestlings by day 6, it was brief, not lasting more than a few minutes, and not sufficient to maintain a stable body temperature in any age group. Our study shows that incipient endothermy is present at an early age in nestling blue tits and may advance faster in reduced broods, but that individual nestlings lack sufficient insulation and thermogenic performance to maintain homeothermy independently during the first week of life. [ABSTRACT FROM AUTHOR]

Background: Current diving physiology postulates that SCUBA divers' arterial blood gas (ABG) levels vary proportionally to environmental pressure, but, to date, ABGs have only been obtained during simulated dives. Also, recent evidence supports the use of the arterial/alveolar (a:A) partial pressures of oxygen (PO2) ratio to predict the arterial PO2 (PaO2) under hyperbaric conditions from measurements obtained at 1 atmosphere absolute (ATA). This work summarizes ABGs obtained in SCUBA divers in real underwater conditions and aims to validate the a:A ratio in predicting PaO2 in this subset of individuals at depth. Methods: The study was approved by the local ethics committee. After cannulating the radial artery of the non-dominant limb, ABGs were sampled at the surface before the dive (A), at depth (15 meters of freshwater (mfw) or 42 mfw) before (B) and after (C) pedaling on a submersed bicycle for 10 minutes, and back at surface (D). After calculating the surface alveolar PO2 for each subject, the a:A ratio was obtained and used to predict PaO2 at depth. A linear regression between measured and predicted PaO2 was reported, along with the goodness-of-fit F test. Results: Six subjects performed the dive at 15 mfw, and four others at 42 mfw. The PaO2 proportionally increased at both depths, remaining stable before and after pedaling. The a:A calculated from the baseline ABG obtained at rest, out of the water, adequately predicted the PaO2 at depth (R2 = 0.97, p<0.001), better at 15 mfw but losing accuracy at 42 mfw. Conclusions: The ABGs confirmed the proportional rise of PaO2 in SCUBA divers underwater. The a:A ratio could be used to predict the magnitude of PaO2 rise at depth to limit exposure to hyperoxia, especially in repetitive recreational dives and professional divers. [ABSTRACT FROM AUTHOR]

Premise: The use of hybrid breeding systems to increase crop yields has been the cornerstone of modern agriculture and is exemplified in the breeding and improvement of cultivated sunflower (Helianthus annuus). However, it is poorly understood what effect supporting separate breeding pools in such systems, combined with continued selection for yield, may have on leaf ecophysiology and specialized metabolite variation. Methods: We analyzed 288 lines of cultivated H. annuus to examine the genomic basis of several specialized metabolites and agronomically important traits across major heterotic groups. Results: Heterotic group identity supports phenotypic divergences between fertility restoring and cytoplasmic male‐sterility maintainer lines in leaf ecophysiology and specialized metabolism. However, the divergence is not associated with physical linkage to nuclear genes that support current hybrid breeding practices in cultivated H. annuus. Additionally, we identified four genomic regions associated with leaf ecophysiology and specialized metabolism that colocalize with previously identified QTLs for quantitative self‐compatibility traits and with S‐protein homolog (SPH) proteins, a recently discovered family of proteins associated with self‐incompatibility and self/nonself recognition in Papaver rhoeas (common poppy) with suggested conserved downstream mechanisms among eudicots. Conclusions: Further work is necessary to confirm the self‐incompatibility mechanisms in cultivated H. annuus and their relationship to the integrative and polygenic architecture of leaf ecophysiology and specialized metabolism in cultivated sunflower. However, because self‐compatibility is a derived quantitative trait in cultivated H. annuus, trait linkage to divergent phenotypic traits may have partially arisen as a potential unintended consequence of historical breeding practices and selection for yield. [ABSTRACT FROM AUTHOR]

Although rhizoctonias from Ceratobasidiaceae, Tulasnellaceae and Serendipitaceae are typical orchid mycobionts, orchid mycorrhizal fungi exhibit vast taxonomic and ecological diversity. This diversity stems from the high specificity of orchid mycorrhizal associations and the remarkable diversity of over 28,000 orchid species. The subtribe Calypsoinae is particularly notable for its diverse mycorrhizal partnerships, including rhizoctonias, ectomycorrhizal and saprotrophic non‐rhizoctonia fungi. However, the mycobionts within certain Calypsoinae lineages, such as the genus Dactylostalix, remain understudied. This study explores the physiological ecology of two photosynthetic Calypsoinae species, Dactylostalix ringens and Dactylostalix uniflora, to gain insight into potentially novel associations and their ecological implications. We analysed the mycorrhizal communities of both Dactylostalix species using high‐throughput ITS metabarcoding of root samples collected from multiple locations. Additionally, we measured the natural abundances of 13C and 15N isotopes in the leaves of the two Dactylostalix species and their co‐occurring autotrophic reference plants, as well as in fungal pelotons isolated from D. ringens, to assess the potential for partial mycoheterotrophy. Our findings revealed that D. ringens and D. uniflora form specialized mycorrhizal associations predominantly with distinct lineages of Oliveonia (Oliveoniaceae, Auriculariales), even in sympatric populations. Stable isotope analysis showed that both Dactylostalix species exhibited conflicting isotopic signals: elevated δ15N values, supporting partial mycoheterotrophy, but lower δ13C values compared to autotrophic plants, suggesting autotrophy. Peloton samples from D. ringens displayed only modest 13C enrichment relative to autotrophic references. These conflicting isotopic signals make it difficult to precisely determine whether both Dactylostalix species are autotrophic or partially mycoheterotrophic. Intriguingly, the 13C and 15N signatures of Dactylostalix species and their pelotons resemble those of many rhizoctonia‐associated orchids. This isotopic evidence implies a niche overlap with endophytic tendencies between rhizoctonias and Oliveonia, suggesting that potential endophytic traits may have facilitated the recruitment of Oliveonia as novel mycorrhizal partners. Furthermore, the mycorrhizal segregation between D. ringens and D. uniflora likely promotes their sympatric coexistence and may contribute to reproductive isolation through ecological specialization. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Seaver, G.A. and Kuzirian, A.M., 2024. Estuary nitrate sources and trends in Buzzards Bay. Journal of Coastal Research, 40(6), 1055–1067. Charlotte (North Carolina), ISSN 0749-0208. The determination of estuary nitrate sources originating through groundwater was the principal objective of this work. This required long timeline (35-year) measurements over many seasonal cycles. Typically, in this study, nitrate sources were an upgradient from estuaries at a significant distance, usually greater than 300 m (1000 ft), whereas groundwater flow that transported the nitrate near the coast in Buzzards Bay, Massachusetts, traveled only 0.45 m/d (1.5 ft/d). Thus, it takes years before a potential newly discovered nitrate source could be confirmed in the estuary. Investigation of estuary nitrate trends and the significance of obtaining winter nitrate measurements to investigations was more fully developed in this work. This showed that determining the estuarian nitrate trends also required a timeline much longer than the variability of the nitrate influx into the estuary. The large, summer-to-winter high nitrate (but not low nitrate) differences and the system's inherent physiological ecology were central to regulating nitrate in an estuary, despite greatly increased groundwater nitrate input. The winter measurement data explained this phenomenon. Finally, the data measurement program completed in Buzzards Bay proved to be ideal in answering these necessarily long timeline questions. The research suggested a new parameter be used to indicate an excess nitrate state of an estuary. These long-term data also allowed meaningful calculations of estuarine and groundwater nitrate and temperature trends. [ABSTRACT FROM AUTHOR]

Niche segregation is a mechanism by which competition between coexisting species is reduced. The ecological niche is a multidimensional space shaped by the conditions and resources that enable the existence of species.We conducted comprehensive univariate and multidimensional analyses of phenotypic traits encompassing morphology, functional performance and ecophysiology, to investigate which phenotypic traits contribute to niche segregation and overlap in two coexisting green lizard species.Our analyses revealed that the main driver of niche segregation was body size. However, when considering size‐corrected phenotypic spaces, ecophysiological traits were still distinct, with little overlap between co‐occurring species. Such differentiation was linked mainly to preferred temperature variance and water loss, highlighting the importance of thermal and hydric niche segregation.Some particular traits such as limb length also contributed to niche segregation being maintained in the morphological space, even when the effect of size was accounted for. Instead, the phenotypic space of functional performance traits (i.e. bite force, locomotor performance) showed the greatest overlap between the two species, thus, less niche segregation was observed, once size effects were removed. Therefore, functional performance traits contribute in a minor proportion to the effective niche segregation between the two species. In light of our results, the most adequate perspective to understand niche segregation in coexisting species is through a multidimensional approach in differentiated phenotypic spaces. Our dismantling of phenotypic traits allowed us to identify niche areas in which trait overlap occurs and others that promote niche segregation, considering or not size effects.Our results suggest that differential use of structural and functional niche space promotes effective niche segregation, potentially reducing direct competition between species. We highlight the importance of studies that include the combination of several phenotypic traits that, as a whole, provide insights to better understand the mechanisms by which coexisting organisms exploit differentiated resources in multidimensional spaces. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

A plant species can have diverse hydraulic strategies to adapt to different environments. However, the water transport divergence of co-occurring species in contrasting habitats remains poorly studied but is important for understanding their ecophysiology adaptation to their environments. Here, we investigated whole-branch, stem and leaf water transport strategies and associated morphology traits of 11 co-occurring plant species in Yuanjiang valley-type savanna (YJ) with dry–hot habitats and Xishuangbanna tropical seasonal rainforest (XSBN) with wet–hot habits and tested the hypothesis that plants in YJ have a lower water transport efficiency than co-occurring species in XSBN. We found high variation in whole-branch, stem and leaf hydraulic conductance (Kshoot; Kstem and Kleaf) between YJ and XSBN, and that Kstem was significantly higher than Kleaf in these two sites (Kstem/Kleaf: 16.77 in YJ and 6.72 in XSBN). These plants in YJ with significantly lower Kshoot and Kleaf but higher sapwood density (WD) and leaf mass per area (LMA) showed a lower water transport efficiency regarding less water loss and the adaptation to the dry–hot habitat compared to co-occurring species in XSBN. In contrast, these co-occurring plants in XSBN with higher Kshoot and Kleaf but lower WD and LMA tended to maximize water transport efficiency and thus growth potential in the wet–hot habitat. Our findings suggest that these co-occurring species employ divergent hydraulic efficiency across YJ and XSBN so that they can benefit from the contrasting hydraulic strategies in adaptation to their respective habitats. [ABSTRACT FROM AUTHOR]

Monitoring environmental conditions over time is essential for understanding how species regulate those conditions to satisfy their physiological needs. Variation in ultraviolet (UV) light exposure, for instance, is crucial for numerous taxa, influencing behaviour as well as essential physiological processes like vitamin D3 synthesis. Yet, despite these considerations, no commercially available data loggers exist to record UV exposures over time, preventing inquiry into this important but neglected fitness demand.To overcome this challenge, I designed the first UV data logger, custom built on the open‐source Arduino platform. This device logs UV exposures (in voltage or converted to UV index) and date‐time information for each UV reading, at user‐defined intervals. The integration of a low‐power timer into the assembly, and its weather‐resistant housing, enables long‐term use (at least several months). The cost of one device (including housing) is under £45/$55 USD.Calibration and performance tests reveal that this device is reliable under various weather conditions and produces accurate UV readings under both artificial lighting and sunlight. Both the device and its customised housing can be easily replicated and expanded upon (e.g. inclusion of additional sensors).Overall, this device represents a crucial first step in our ability to better characterise UV exposure patterns in habitats for physiological ecology studies. Exposure to UV light is adaptive for many types of organisms, both in the wild and in captivity (e.g. zoos and private hobbyists), and so I expect a broad array of scientific and public users alike to benefit from using this device. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Globally, the combustion of fossil fuels represents the vast majority of greenhouse gas emissions, and as such, a transition to renewable forms of energy provides the greatest potential for mitigating climate warming. Although solar photovoltaic energy generation is a leading climate solution, these energy facilities have a significant spatial footprint. Naturally, concerns regarding the coexistence of solar development in agriculturally productive and pristine native ecosystems remain. This study offers insight for how plants respond to novel environmental conditions within a solar array and contextualizes results to inform future array siting, design, and management to realize a sustainable solar energy future. Summary: Photovoltaic (PV) solar arrays impose dynamic shading regimes and redistribute precipitation to the ecosystems beneath, leading to spatial and temporal heterogeneity in plant growth environments. Although PV are known to alter ecosystem‐level processes in managed and native landscapes, the control of PV‐induced microenvironments on plant ecophysiological responses are largely unexplored. A more robust and mechanistic understanding of how PV microenvironments control plant response will inform management of existing solar arrays and provide insight for future arrays designed to enhance ecosystem services.Here, we evaluated carbon (photosynthetic parameters) and water relations (daily patterns of leaf water potential (ψL) and stomatal conductance (gsw)) in a C3 perennial grass (Bromus inermis) across PV microsites within a 1.6 ha (1.2 MW) array in semiarid Colorado, USA.Light‐saturated photosynthetic rate was surprisingly consistent spatially, not differing between plants growing in near full sun (between PV rows) versus those growing in shadier microsites beneath panels (~28% of full sunlight). Additionally, plants located in microsites receiving only direct sunlight in the morning, when air temperature and vapor pressure deficits (VPD) were low, had greater ψL and gsw than plants receiving direct sunlight primarily in the hotter drier afternoon.Thus, while soil moisture is a primary control of plant productivity in most water‐limited grasslands, we found that VPD was a better predictor of daily patterns of leaf‐level photosynthetic and water relations responses that control aboveground biomass production in a PV array. These findings provide new mechanistic insight for evaluating vegetation management strategies in semiarid PV arrays. [ABSTRACT FROM AUTHOR]

Algal physiological ecology on submarine groundwater discharge (SGD) influenced reefs is likely shaped by intermittent, tidally-driven estuarine conditions that occur with SGD fluxes of fresh-to-brackish groundwater from the subterranean estuary to reef ecosystems. SGD is a common inconspicuous feature worldwide on reefs of basaltic high islands and continental margins. Yet, SGD-driven dynamics of algal physiology are not well understood. To understand how invasive species have physiologically outcompeted native species on many SGD-influenced reefs, physiology in tissue water potential (TWP) regulation, photosynthesis, nitrogen storage, and cellular anatomy were measured across a gradient of SGD-influence, for four Rhodophyte species. Compared with non-SGD conditions, SGD was associated with higher TWP, larger medulla cells with thinner walls, and thinner cortical cell walls for two invasives, Gracilaria salicornia and Acanthophora spicifera, higher photosynthetic rates in G. salicornia, greater nitrogen concentration for A. spicifera and G. salicornia, and increased δ 15N ratios for A. spicifera, G. salicornia, and native Laurencia dendroidea. Distinct physiological strategies were measured for the two invasive species across the gradient of SGD-influence, and for L. dendroidea and Gracilaria perplexa offshore. This study illuminates species-specific physiological response, and how introduced opportunistic species may outcompete native species under conditions of SGD. [ABSTRACT FROM AUTHOR]

Our behavior and mental states are constantly shaped by our environment and experiences. However, little is known about the response of brain functional connectivity to environmental, physiological, and behavioral changes on different timescales, from days to months. This gives rise to an urgent need for longitudinal studies that collect high-frequency data. To this end, for a single subject, we collected 133 days of behavioral data with smartphones and wearables and performed 30 functional magnetic resonance imaging (fMRI) scans measuring attention, memory, resting state, and the effects of naturalistic stimuli. We find traces of past behavior and physiology in brain connectivity that extend up as far as 15 days. While sleep and physical activity relate to brain connectivity during cognitively demanding tasks, heart rate variability and respiration rate are more relevant for resting-state connectivity and movie-watching. This unique data set is openly accessible, offering an exceptional opportunity for further discoveries. Our results demonstrate that we should not study brain connectivity in isolation, but rather acknowledge its interdependence with the dynamics of the environment, changes in lifestyle, and short-term fluctuations such as transient illnesses or restless sleep. These results reflect a prolonged and sustained relationship between external factors and neural processes. Overall, precision mapping designs such as the one employed here can help to better understand intraindividual variability, which may explain some of the observed heterogeneity in fMRI findings. The integration of brain connectivity, physiology data and environmental cues will propel future environmental neuroscience research and support precision healthcare. Functional brain activity is often measured during a single scanning session which neglects behavioral, physiological and lifestyle effects on brain activity. This study presents functional neuroimaging data from 30 neuroimaging session across 15 weeks from one participant and reveals relationships between human daily behavior and brain function under different stimuli. [ABSTRACT FROM AUTHOR]

Prey alter their foraging when threatened by predators. Two mutually inclusive hypotheses explain this response. The first entails that defence behaviours to minimise exposure to predators prevent prey from achieving their preferred diet, while the second postulates that prey deliberately change their diet to fulfil new stress‐induced nutritional demands.We combined field observations and laboratory experiments to determine which hypothesis dictates snail dietary responses to risk of beetle predation.Snails exposed to predation‐risk reduced activity, increased climbing, increased respiration, ate distinctively to achieve a certain nutrient target, and preferred eating on the cage floor at the costs of nutritional imbalance and elevated risk.When only carbohydrates‐rich food was on the floor, stressed snails reduced activity and foraged less, but when only protein‐rich food was on the floor snails increased activity and consumed more carbohydrates than their no‐risk conspecifics.This outcome suggests that nutrient accessibility may determine which hypothesis governs the prey dietary reaction to predation risk. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Potato is the fourth most consumed crop in the world. More than half of the crop is stored for three to nine months at cold temperatures (3–10 °C) for the fresh and seed market. One of the main causes of fresh potato waste in the retail supply chain is the processing of fungal and bacterial rots during storage. Dry rot is a fungal disease that mainly affects the potato crop during storage and is responsible for 1% of tuber losses in the UK. It is produced by Fusarium spp., such as Fusarium sambucinum and F. oxysporum, which can lead to the accumulation of mycotoxins in the potato tuber. Little is known about the impact of environmental factors on the accumulation of mycotoxins in potato tubers. Understanding the ecophysiology of these fungi is key to mitigating their occurrence under commercial storage conditions. Therefore, this work aimed to elucidate the effect of three different temperatures (5, 10, and 15 °C) and two different water activities (aw; 0.97, 0.99) on the ecophysiology and mycotoxin accumulation of F. sambucinum and F. oxysporum in a potato-based semi-synthetic medium. The mycotoxin accumulation was then studied in vivo, in potato tubers cultivated under organic farming conditions, stored for 40 days at 8.5 °C. Results showed that higher temperatures and aw enhanced fungal growth, lag time, and mycotoxin accumulation in vitro. Growth rate was 2 and 3.6 times higher when the temperature increased from 5 to 10 and 15 °C, respectively. Six different mycotoxins (T-2, HT-2, diacetoxyscirpenol, 15-acetoxyscirpenol, neosolaniol, and beauvericin) were detected in vitro and in vivo. T-2 was the most abundant mycotoxin detected in vitro, observing 106 ng of T-2/g media after 21 days of incubation at 10 °C and 0.99 aw. Due to the long period of time that potato tubers spend in storage, the fluctuations of environmental factors, such as temperature and relative humidity, could promote the development of fungal rot, as well as mycotoxin accumulation. This could result in important food and economic losses for the potato market and a threat to food safety. [ABSTRACT FROM AUTHOR]

Filamentous bacteria are one of the main components of activated sludge microorganisms, which not only support flocculent bacteria in forming sludge flocs but also easily lead to sludge bulking. This article summarizes the high-throughput sequencing technology and database construction that integrates the FISH probe and 16s rRNA gene of filamentous bacteria. The detection frequency and abundance were statistically analyzed to determine the core filamentous bacteria. The filamentous bacteria searchable in the NCBI database belong to six phyla and 42 genera, with a total of 94 species. The core filamentous bacteria in the expanded activated sludge include Microthrix parvicella (M. parvicella), type 0092, Mycobacterium fortuitum, etc. The physiological ecology of the core filamentous bacteria is discussed in detail, aiming to establish targeted sludge expansion control strategies, reduce the incidence and harm of sludge expansion, and propose that future research needs to promote further development in the field of environmental microbiology. [ABSTRACT FROM AUTHOR]

Introduction: The carbon isotope ratios (δ13C) of essential amino acids (EAAs), including valine, leucine, isoleucine, threonine, and phenylalanine, in producers are crucial for explaining food-web structures in marine ecosystems. However, few studies have tested the variability of δ13C-EAA values in marine macrophytes, such as seagrass and macroalgae, under changing environmental conditions. Methods: In this study, we examined the responses of δ13C-EAA values in macrophytes to environmental changes and explored their usefulness in characterizing macrophyte groups and local environments. We tested seagrass and macroalgae collected at different spatial and temporal scales in the field, as well as lab-cultured Ulva algae at various temperature gradients (12°C, 20°C, and 27.5°C) with additional nitrogen sources. Results: We found that δ13C-EAA values in macroalgae were significantly altered by seasonality and the interactive effects of temperature and nitrogen addition in comparison with mean-centered δ13C-EAA values (normalized δ13C-EAA values relative to the mean of the overall EAAs). The δ13C-EAA values detected in macroalgae within a local environment correlated with those of a cooccurring grazer, Caprella. Based on mean-centered δ13C-EAA values, macrophyte groups were distinguishable from other group (i.e., the bacteria group) even under diverse environmental conditions. Moreover, the seagrass group did not overlap with the green and the brown macroalgal group, but overlapped considerably with the red macroalgal group. Discussion: These results suggest that the macrophyte-specific mean-centered δ13C-EAA values may be fairly consistent across broad spatial and temporal scales. Despite significant variation in δ13C-EAA values, the consistency in meancentered δ13C-EAA values among specific macrophyte groups provides valuable insight into the characteristics of local trophic bases in regions under pressure from dramatic environmental changes. [ABSTRACT FROM AUTHOR]

Premise: Plant functional traits are often used to describe the spectra of ecological strategies used by different species. Here, we demonstrate a machine learning approach for identifying the traits that contribute most to interspecific phenotypic divergence in a multivariate trait space. Methods: Descriptive and predictive machine learning approaches were applied to trait data for the genus Helianthus, including random forest and gradient boosting machine classifiers and recursive feature elimination. These approaches were applied at the genus level as well as within each of the three major clades within the genus to examine the variability in the major axes of trait divergence in three independent species radiations. Results: Machine learning models were able to predict species identity from functional traits with high accuracy, and differences in functional trait importance were observed between the genus and clade levels indicating different axes of phenotypic divergence. Conclusions: Applying machine learning approaches to identify divergent traits can provide insights into the predictability or repeatability of evolution through the comparison of parallel diversifications of clades within a genus. These approaches can be implemented in a range of contexts across basic and applied plant science from interspecific divergence to intraspecific variation across time, space, and environmental conditions. [ABSTRACT FROM AUTHOR]

Contemporary symbioses in extreme environments can give an insight into mechanisms that stabilize species interactions during environmental change. The intertidal sea anemone, Anthopleura elegantissima, engages in a nutritional symbiosis with microalgae similar to tropical coral, but withstands more intense environmental fluctuations during tidal inundations. In this study, we compare baseline symbiotic traits and their sensitivity to thermal stress within and among anemone aggregations across the intertidal using a laboratory‐based tank experiment to better understand how fixed genotypic and plastic environmental effects contribute to the successful maintenance of this symbiosis in extreme habitats. High intertidal anemones had lower baseline symbiont‐to‐host cell ratios under control conditions, but their symbionts had higher baseline photosynthetic efficiency compared to low intertidal anemone symbionts. Symbiont communities were identical across all samples, suggesting that shifts in symbiont density and photosynthetic performance could be an acclimatory mechanism to maintain symbiosis in different environments. Despite lower baseline symbiont‐to‐host cell ratios, high intertidal anemones maintained greater symbiont‐to‐host cell ratios under heat stress compared with low intertidal anemones, suggesting greater thermal tolerance of high intertidal holobionts. However, the thermal tolerance of clonal anemones acclimatized to different zones was not explained by tidal height alone, indicating additional environmental variables contribute to physiological differences. Host genotype significantly influenced anemone weight, but only explained a minor proportion of variation among symbiotic traits and their response to thermal stress, further implicating environmental history as the primary driver of holobiont tolerance. These results indicate that this symbiosis is highly plastic and may be able to acclimatize to climate change over ecological timescales, defying the convention that symbiotic organisms are more susceptible to environmental stress. [ABSTRACT FROM AUTHOR]

Various environmental factors not only affect plant growth and physiological responses individually but also interact with each other. To examine the impact of light intensity on the drought responses of sweet basil, plants were subjected to maintenance of two substrate volumetric water contents (VWC) using a sensor-based automated irrigation system under two distinct light intensities. The VWC threshold was set to either a dry (0.2 m3·m−3) or sufficiently wet condition (0.6 m3·m−3) under low (170 μmol·m−2·s−1) or high light intensities (500 μmol·m−2·s−1). The growth and physiological responses of sweet basil (Ocimum basilicum L.) were observed over 21 days in the four treatment groups, where the combination of two environmental factors was analyzed. Under high light intensity, sweet basil showed lower Fv/Fm and quantum yield of PSII, compared to that under low light intensity, regardless of drought treatment. Fourteen days after drought treatment under high light intensity, stomatal conductance and the photosynthetic rate significantly reduced. Whereas plants under low light intensity showed similar stomatal conductance and photosynthetic rates regardless of drought treatment. Assessment of shoot and root dry weights revealed that plant growth decline caused by drought was more pronounced under high light intensity than under low light intensity. Thus, sweet basil showed significant declines in growth and physiological responses owing to drought only under high light intensity; no significant changes were observed under low light intensity. [ABSTRACT FROM AUTHOR]

Photosynthetic response studies at different light intensities facilitate understanding plant physiology, optimizing management and sustainable use of species. The purpose of the research was to evaluate the photosynthetic response of G. angustifolia and B. vulgaris at different light intensities. Photosynthetic assimilation measurements were performed using a portable iFL - LCpro-SD system. The compensation point (┌ ⁕) was determined by three A/Ci curves under three different light intensity levels. The evaluation of the photosynthetic response to increasing light intensity was from 25 to 1800 PPFD μmol m-2s-1. G. angustifolia presented a ┌ ⁕ of 73.9 μmol CO2 m-2s-1, indicating higher carbon capture efficiency at lower concentrations compared to B. vulgaris, which showed a ┌ ⁕ of 88.1 μmol CO2 m-2s-1. Furthermore, G. angustifolia exhibited a lower diurnal respiration rate (Rd) (0.33 μmol CO2 m-2s-1, which optimizes its energy efficiency, while B. vulgaris presented a higher Rd (1.08 μmol CO2 m-2s-1, implying higher energy consumption under low light intensity conditions. G. angustifolia did not show photoinhibition, as its photosynthetic assimilation rate increased continuously with light. In contrast, B. vulgaris experienced photoinhibition starting at 700 μmol m-2s-1 of PPFD. These findings show that G. angustifolia is better adapted to capture carbon under conditions of low CO2, concentrations and high light intensities, while B. vulgaris seems to be better adapted to environments with higher CO2 concentrations. [ABSTRACT FROM AUTHOR]

Aim: The scale of environmental data is often defined by their extent (spatial area, temporal duration) and resolution (grain size, temporal interval). Although describing climate data scale via these terms is appropriate for most meteorological applications, for ecology and biogeography, climate data of the same spatiotemporal resolution and extent may differ in their relevance to an organism. Here, we propose that climate proximity, or how well climate data represent the actual conditions that an organism is exposed to, is more important for ecological realism than the spatiotemporal resolution of the climate data. Location: Temperature comparison in nine countries across four continents; ecological case studies in Alberta (Canada), Sabah (Malaysia) and North Carolina/Tennessee (USA). Time Period: 1960–2018. Major Taxa Studied: Case studies with flies, mosquitoes and salamanders, but concepts relevant to all life on earth. Methods: We compare the accuracy of two macroclimate data sources (ERA5 and WorldClim) and a novel microclimate model (microclimf) in predicting soil temperatures. We then use ERA5, WorldClim and microclimf to drive ecological models in three case studies: temporal (fly phenology), spatial (mosquito thermal suitability) and spatiotemporal (salamander range shifts) ecological responses. Results: For predicting soil temperatures, microclimf had 24.9% and 16.4% lower absolute bias than ERA5 and WorldClim respectively. Across the case studies, we find that increasing proximity (from macroclimate to microclimate) yields a 247% improvement in performance of ecological models on average, compared to 18% and 9% improvements from increasing spatial resolution 20‐fold, and temporal resolution 30‐fold respectively. Main Conclusions: We propose that increasing climate proximity, even if at the sacrifice of finer climate spatiotemporal resolution, may improve ecological predictions. We emphasize biophysically informed approaches, rather than generic formulations, when quantifying ecoclimatic relationships. Redefining the scale of climate through the lens of the organism itself helps reveal mechanisms underlying how climate shapes ecological systems. [ABSTRACT FROM AUTHOR]

The process of natural forest rejuvenation, which refers to the self-renewal of forest ecosystems, encompasses the substitution of mature trees with the succeeding generation and is subject to the influence of environmental factors. The characteristics of the stands themselves both impact and determine the spatial organization of tree regeneration. The natural regeneration of the Atlas cedar follows a complex set of eco-physiological processes involving several environmental factors during the different phases of its establishment and development. Thus, it is noteworthy that the cedar always remains closely associated with the holm oak, forming well-stable mixed associations. Therefore, this study investigates the cedar stand of Chelia, affected by dieback where regeneration seems inconstant. Accordingly, the study describes the stand’s spatial structure to understand spatial patterns’ mechanisms the areas of forest that contain a variety of different tree speciem in the north-east of Algeria .Using data from four rectangular plots (60 m × 40 m) temporarily established in the mountain of Chelia, all the seedlings were charted, measured, and located through their (xi, yi) coordinates In addition, two vertical measurements of holm oak crown diameter were recorded for each tree, along with other structural variables. Then, the pair correlation functions were used to investigate uni- and bivariate spatial point patterns to assess the spatial relationship between the cedar seedlings and the holm oak undergrowth. We found that the univariate pair correlation function showed a spatial aggregation of seedlings, concerning the holm oak pattern, which was regular only at small scales but was predominantly random. The bivariate pair correlation function revealed that regeneration was found to be clumped and the spatial association between holm oak and Atlas cedar seedlings. [ABSTRACT FROM AUTHOR]

The round goby (Neogobius melanostomus) is the fastest spreading invasive fish in the Laurentian Great Lakes, and concurrent invasions are occurring globally. To inform management and mitigation strategies, metabolic rate of adult round goby has been rigorously quantified, but metabolism of the juvenile life stages represents an important knowledge gap. Here, we measured routine and maximum metabolic rates (RMR and MMR) of early juvenile round goby (mass 0.007–0.07 g, mean 0.02 g; total length 6.6–19.4 mm, mean 13.7 mm), ~100× smaller than any round goby measured previously. To understand how metabolism may be affected by a warming climate, we reared round goby at several ecologically relevant temperatures (15°C, 19°C, and 23°C) and a projected surface temperature under climate change scenarios (27°C). We tested early juveniles at two separate and distinct ages (6–7 weeks and 12–14 weeks post-hatch). Growth was highest at 23°C compared to 15°C and 27°C, but this pattern only emerged after 12–14 weeks of development. Routine metabolic rates increased over 2-fold between fish reared at 15°C vs. 27°C (Q10 = 1.98), but we found no clear difference in our estimation of the “scope for activity” (i.e., maximum—routine metabolic rate) across temperatures, suggesting a wide thermal performance curve. We also found that the bioenergetics models previously developed for adults do not effectively translate to juveniles; the current models underestimated observed RMR values by ~20–60% depending on temperature. Overall, data from this study can be used to improve bioenergetic modeling in the round goby by considering these earlier life stages and fill an important gap of knowledge in our understanding of an ecologically invasive species.

The ecophysiological and ecohydrological impacts of climate change and progressively increasing atmospheric carbon dioxide (CO2) concentration on agroecosystems are not well understood compared to the forest ecosystems. In this study, we utilized the presence of old apple and pear trees in the alpine valleys of Northern Italy (maintained for cultural heritage purposes) to investigate climate-scale physiological responses. We developed long-term tree-ring stable isotopic records (δ13C and δ18O) from apple (1976-2021) and pear trees (1943-2021). This allowed the reconstruction of key ecophysiological processes like the variations in intrinsic water use efficiency (iWUE), and we investigated how these trees responded to climate and CO2 changes over decades. Results showed a slight declining trend in carbon discrimination (Δ13C) while intercellular CO2 concentration (Ci) for both species has been increasing since the late 1980s. Concurrently both species exhibited a rising trend in iWUE, with apple trees demonstrating higher efficiency, which appears to be primarily driven by the CO2-fertilization effect. The concomitant trends in tree-ring δ18O suggested a relatively stable local hydroclimate during the study period with some species-specific responses. Analyses further revealed that minimum growing season temperature, not precipitation was the most significant factor influencing the rise in iWUE alongside with CO2 fertilization effect. Analyses of species’ δ13C coupled with their respective δ18O confirmed that the rise in iWUE was due to increased carbon assimilation rather than a decline in evapotranspiration. Moreover, coupled δ13C–δ18O analyses suggested increasing trends in carbon assimilation, with apple trees showing higher inter-decadal variations. These long-term records provide a unique opportunity to test and calibrate how these systems respond to recent and anticipated climate change.

Optical-based remote sensing offers great potential for phenotyping vegetation traits and functions for a range of applications including vegetation monitoring and assessment. A key strength of optical-based approaches is the underlying mechanistic link to vegetation physiology, biochemistry, and structure that influences a spectral signal. By exploiting spectral variation driven by plant physiological response to environment, remotely sensed products can be used to estimate vegetation traits and functions. However, oftentimes these products are proxies based on covariance, which can lead to misinterpretation and decoupling under certain scenarios. This viewpoint will discuss (i) the optical properties of vegetation, (ii) applications of vegetation indices, solar-induced fluorescence, and machine-learning approaches, and (iii) how covariance can lead to good empirical proximation of plant traits and functions. Understanding and acknowledging the underlying mechanistic basis of plant optics must be considered as remotely sensed data availability and applications continue to grow. Doing so will enable appropriate application and consideration of limitations for the use of optical-based remote sensing for phenotyping applications.

Abstract Background Magnetotactic bacteria (MTB) are a unique group of microorganisms that sense and navigate through the geomagnetic field by biomineralizing magnetic nanoparticles. MTB from the phylum Nitrospirota (previously known as Nitrospirae) thrive in diverse aquatic ecosystems. They are of great interest due to their production of hundreds of magnetite (Fe3O4) magnetosome nanoparticles per cell, which far exceeds that of other MTB. The morphological, phylogenetic, and genomic diversity of Nitrospirota MTB have been extensively studied. However, the metabolism and ecophysiology of Nitrospirota MTB are largely unknown due to the lack of cultivation techniques. Methods Here, we established a method to link the morphological, genomic, and metabolic investigations of an uncultured Nitrospirota MTB population (named LHC-1) at the single-cell level using nanoscale secondary-ion mass spectrometry (NanoSIMS) in combination with rRNA-based in situ hybridization and target-specific mini-metagenomics. Results We magnetically separated LHC-1 from a freshwater lake and reconstructed the draft genome of LHC-1 using genome-resolved mini-metagenomics. We found that 10 LHC-1 cells were sufficient as a template to obtain a high-quality draft genome. Genomic analysis revealed that LHC-1 has the potential for CO2 fixation and NO3 − reduction, which was further characterized at the single-cell level by combining stable-isotope incubations and NanoSIMS analyses over time. Additionally, the NanoSIMS results revealed specific element distributions in LHC-1, and that the heterogeneity of CO2 and NO3 − metabolisms among different LHC-1 cells increased with incubation time. Conclusions To our knowledge, this study provides the first metabolic measurements of individual Nitrospirota MTB cells to decipher their ecophysiological traits. The procedure constructed in this study provides a promising strategy to simultaneously investigate the morphology, genome, and ecophysiology of uncultured microbes in natural environments. Video Abstract