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Anthropogenic stressors can have an impact in a broad range of physiological processes and can be a major selective force leading to rapid evolution and local population adaptation. In this study, three populations of the invasive crayfish Procambarus clarkii were investigated. They are geographically separated for at least 20 years, and live in different abiotic environments: a freshwater inland lake (Salagou lake) with no major anthropogenic influence and two other coastal wetlands regularly polluted by pesticides along the Mediterranean coast (Camargue region and Bages-Sigean lagoon). Collected adults were genetically characterized using the mitochondrial COI gene and haplotype frequencies were analyzed for genetic variability within and between populations. Results revealed a higher genetic diversity for these invasive populations than any previous report in France, with more than seven different haplotypes in a single population. The contrasting genetic diversity between the Camargue and the other two populations suggest different times and sources of introduction. To identify differences in key physiological responses between these populations, individuals from each population were maintained in controlled conditions. Data on oxygen consumption rates indicate that the Salagou and Bages-Sigean populations possess a high inter-individual variability compared to the Camargue population. The low individual variability of oxygen consumption and low genetic diversity suggest a specific local adaptation for the Camargue population. Population-specific responses were identified when individuals were exposed to a pesticide cocktail containing azoxystrobin and oxadiazon at sublethal concentrations. The Salagou population was the only one with altered hydro-osmotic balance due to pollutant exposure and a change in protease activity in the hepatopancreas. These results revealed different phenotypic responses suggesting local adaptations at the population level. [ABSTRACT FROM AUTHOR]

Interspecific competition can hinder populations from evolutionarily adapting to abiotic environments, particularly by reducing population size and niche space; and feedback may arise between competitive ability and evolutionary adaptation. Here we studied populations of two model bacterial species, Escherichia coli and Pseudomonas fluorescens, that evolved in monocultures and cocultures for approximately 2400 generations at three temperatures. The two species showed a reversal in competitive dominance in cocultures along the temperature gradient. Populations from cocultures where they had been competitively dominant showed the same magnitude of fitness gain as those in monocultures. However, competitively inferior populations in cocultures showed limited abiotic adaptation compared with those in monocultures. The inferior populations in cocultures were also more likely to evolve weaker interspecific competitive ability, or go extinct. The possible competitive ability‐adaptation feedback may have crucial consequences for population persistence. [ABSTRACT FROM AUTHOR]

This article discusses the role of environmental factors in shaping the plant microbiome, specifically focusing on the influence of bacterial and fungal communities on plant responses to water stress. The article highlights recent studies that examine the impact of different genotypes and levels of water stress on bacterial communities in quinoa plants and the relationship between environmental factors and fungal communities in apple fruit. The findings emphasize the importance of understanding plant microbiome dynamics for developing effective crop protection strategies and improving agricultural sustainability. The article suggests that microbiome-based strategies, which manipulate the plant microbiome, offer promising approaches for addressing crop productivity challenges while minimizing the use of harmful chemicals. [Extracted from the article]

Allometry reflects the quantitative relationship between the allocation of resources among different organs. Understanding patterns of forest biomass allocation is critical to comprehending global climate change and the response of terrestrial vegetation to climate change. By collecting and reorganizing the existing allometric models of tree species in China, we established a database containing over 3000 empirical allometric models. Based on this database, we analyzed the model parameters and the effect of climate on forest biomass allocation under the context of 'optimal allocation theory'. We showed that (1) the average and median exponent of power functions for above-ground biomass were 2.344 and 2.385, respectively, which significantly deviated from the theoretical prediction of 2.667 by metabolic theory (p < 0.01). (2) The parameters of the allometric model were not constant, and not significantly correlated with temperature, precipitation, latitude, and elevation (p > 0.05), but were more closely related to individual size (p < 0.01). (3) Among different types of forests, the proportion of above-ground biomass in tropical rainforests and subtropical evergreen rainforests was significantly higher than that in temperate forests and boreal forests (p < 0.05). The proportion of trunk and branch biomass allocated to tropical rainforest was significantly higher than that of boreal forest (p < 0.05), while the proportion of root and leaf biomass allocated to tropical rainforest was significantly lower than that of boreal forest (p < 0.05). (4) The abiotic environment plays a crucial role in determining the allocation of plant biomass. The ratio of below-ground/above-ground biomass is significantly and negatively correlated with both temperature and rainfall (p < 0.01), and significantly and positively correlated with altitude and latitude (p < 0.01). This means that as temperature and rainfall increase, there is a decrease in the amount of biomass allocated to below-ground structures such as roots. On the other hand, as altitude and latitude increase, there is an increase in below-ground biomass allocation. These findings highlight the importance of considering the influence of abiotic factors on plant growth and development. [ABSTRACT FROM AUTHOR]

Introduced plants create lasting abiotic and biotic changes to soil that are increasingly implicated as major drivers of invasion success, yet models for investigating patterns in the impacts of these soil legacies are lacking. Here, we used Bohemian knotweed (Reynoutria × bohemica) to present a novel approach for testing whether accounting for diverse evolutionary drivers can clarify how an invader's soil legacy mediates its success. For most tested species, R. × bohemica's soil legacy did not influence seedling performance irrespective of its evolutionary history or the evolutionary novelty of species that share its soil. However, we found the relative importance of legacy effects versus other mechanisms of invader dominance depends on the life stage of the plants growing in soil conditioned by the invader. While the effects of R. × bohemica's soil legacy on seedling performance were context dependent, emergence was, on average, higher in R. × bohemica‐conditioned soils than in unconditioned soils. Thus, contrary to theory, R. × bohemica's soil legacy not only fails to impede potential competitors but may also facilitate them. Our results are particularly powerful: we detected novel insights in the face of biological complexity, even for R. × bohemica, which likely does not depend on heterospecific plant–soil feedbacks for its competitive dominance in its introduced range. Designing rigorous investigations that explore how plant species' evolutionary histories mediate an invader's soil legacy across diverse abiotic environments, as shown here, is key for producing insights in other systems. [ABSTRACT FROM AUTHOR]

The speed of population adaptation to changing biotic and abiotic environments is determined by the interaction between genetic drift, positive selection and linkage effects. Many marine species (fish, crustaceans), invertebrates and pathogens of humans and crops, exhibit sweepstakes reproduction characterized by the production of a very large amount of offspring (fecundity phase) from which only a small fraction may survive to the next generation (viability phase). Using stochastic simulations, we investigate whether the occurrence of sweepstakes reproduction affects the efficiency of a positively selected unlinked locus, and thus, the speed of adaptation since fecundity and/or viability have distinguishable consequences on mutation rate, probability and fixation time of advantageous alleles. We observe that the mean number of mutations at the next generation is always the function of the population size, but the variance increases with stronger sweepstakes reproduction when mutations occur in the parents. On the one hand, stronger sweepstakes reproduction magnifies the effect of genetic drift thus increasing the probability of fixation of neutral allele and decreasing that of selected alleles. On the other hand, the time to fixation of advantageous (as well as neutral) alleles is shortened by stronger sweepstakes reproduction. Importantly, fecundity and viability selection exhibit different probabilities and times to fixation of advantageous alleles under intermediate and weak sweepstakes reproduction. Finally, alleles under both strong fecundity and viability selection display a synergistic efficiency of selection. We conclude that measuring and modelling accurately fecundity and/or viability selection are crucial to predict the adaptive potential of species with sweepstakes reproduction. [ABSTRACT FROM AUTHOR]

Root-knot nematodes (Meloidogyne spp., RKN) are among the most destructive endoparasitic nematodes worldwide, often leading to a reduction of crop growth and yield. Insights into the dynamics of host-RKN interactions, especially in varied biotic and abiotic environments, could be pivotal in devising novel RKN mitigation measures. Plant growth-promoting bacteria (PGPB) involves different plant growth-enhancing activities such as biofertilization, pathogen suppression, and induction of systemic resistance. We summarized the up-todate knowledge on the role of PGPB and abiotic factors such as soil pH, texture, structure, moisture, etc. in modulating RKN-host interactions. RKN are directly or indirectly affected by different PGPB, abiotic factors interplay in the interactions, and host responses to RKN infection. We highlighted the tripartite (host-RKNPGPB) phenomenon with respect to (i) PGPB direct and indirect effect on RKNhost interactions; (ii) host influence in the selection and enrichment of PGPB in the rhizosphere; (iii) how soil microbes enhance RKN parasitism; (iv) influence of host in RKN-PGPB interactions, and (v) the role of abiotic factors in modulating the tripartite interactions. Furthermore, we discussed how different agricultural practices alter the interactions. Finally, we emphasized the importance of incorporating the knowledge of tripartite interactions in the integrated RKN management strategies. [ABSTRACT FROM AUTHOR]

This article discusses the important role that microbes play in plant ecology and evolution. Microbes, which include diverse soil and foliar microbial communities, have a significant impact on various aspects of plant biology. They can influence maternal effects, phenotypic plasticity, and natural selection in plants. Ignoring the presence and effects of microbes can lead to a misunderstanding of plant processes and outcomes. Therefore, it is crucial for plant ecologists and evolutionary biologists to consider the influence of microbial communities in their research to gain a more accurate understanding of plant biology in the natural world. [Extracted from the article]

An understanding of biological fitness is central to theory and practice in ecology and evolution, yet fitness remains an elusive concept to define and is challenging to measure accurately. Fitness reflects an individual's ability to pass its alleles on to subsequent generations. Researchers often quantify proxies for fitness, such as survival, growth, or reproductive success. However, it can be difficult to determine lifetime fitness, especially for species with long life spans. The abiotic and biotic environment strongly affects the expression of fitness, which means that fitness components can vary through both space and time. This spatial and temporal heterogeneity results in the impressive range of adaptations that we see in nature. Here, we review definitions of fitness and approaches to measuring fitness at the level of genes, individuals, genotypes, and populations and highlight that fitness is a key concept linking ecological and evolutionary thought. [ABSTRACT FROM AUTHOR]

In nature, plants are constantly colonized by a massive diversity of microbes engaged in mutualistic, pathogenic or commensal relationships with the host. Molecular patterns present in these microbes activate pattern-triggered immunity (PTI), which detects microbes in the apoplast or at the tissue surface. Whether and how PTI distinguishes among soil-borne pathogens, opportunistic pathogens, and commensal microbes within the soil microbiota remains unclear. PTI is a multimodal series of molecular events initiated by pattern perception, such as Ca2+ influx, reactive oxygen burst, and extensive transcriptional and metabolic reprogramming. These short-term responses may manifest within minutes to hours, while the long-term consequences of chronic PTI activation persist for days to weeks. Chronic activation of PTI is detrimental to plant growth, so plants need to coordinate growth and defense depending on the surrounding biotic and abiotic environments. Recent studies have demonstrated that root-associated commensal microbes can activate or suppress immune responses to variable extents, clearly pointing to the role of PTI in root–microbiota interactions. However, the molecular mechanisms by which root commensals interfere with root immunity and root immunity modulates microbial behavior remain largely elusive. Here, with a focus on the difference between short-term and long-term PTI responses, we summarize what is known about microbial interference with host PTI, especially in the context of root microbiota. We emphasize some missing pieces that remain to be characterized to promote the ultimate understanding of the role of plant immunity in root–microbiota interactions. [ABSTRACT FROM AUTHOR]

The aerosol transmission of coronavirus disease in 2019, along with the spread of other respiratory diseases, caused significant loss of life and property; it impressed upon us the importance of real-time bioaerosol detection. The complexity, diversity, and large spatiotemporal variability of bioaerosols and their external/internal mixing with abiotic components pose challenges for effective online bioaerosol monitoring. Traditional methods focus on directly capturing bioaerosols before subsequent time-consuming laboratory analysis such as culture-based methods, preventing the high-resolution time-based characteristics necessary for an online approach. Through a comprehensive literature assessment, this review highlights and discusses the most commonly used real-time bioaerosol monitoring techniques and the associated commercially available monitors. Methods applied in online bioaerosol monitoring, including adenosine triphosphate bioluminescence, laser/light-induced fluorescence spectroscopy, Raman spectroscopy, and bioaerosol mass spectrometry are summarized. The working principles, characteristics, sensitivities, and efficiencies of these real-time detection methods are compared to understand their responses to known particle types and to contrast their differences. Approaches developed to analyze the substantial data sets obtained by these instruments and to overcome the limitations of current real-time bioaerosol monitoring technologies are also introduced. Finally, an outlook is proposed for future instrumentation indicating a need for highly revolutionized bioaerosol detection technologies. [ABSTRACT FROM AUTHOR]

Urbanization frequently alters the biotic and abiotic environmental context. Variation in both the biotic and abiotic environment can result in selection mosaics that lead to locally adapted phenotypes. Ecological changes to urban environments can result in evolutionary responses across a diverse array of plants and animals, but the effects of urbanization on local adaptation and coevolution between species remain largely unstudied.Using a common garden experiment of 30 populations and 1080 plants, we tested for local adaptation in the mutualism between white clover (Trifolium repens) and rhizobia (Rhizobium leguminosarum symbiovar trifolii) along an urbanization gradient. We asked: (Q1) are white clover and rhizobia locally adapted? (Q2) Does nitrogen (N) addition mediate the strength of local adaptation? (Q3) Is the strength of local adaptation in host plants related to the strength of local adaptation in rhizobia, as expected if white clover and rhizobia are coadapting? And (Q4) how does the degree of local adaptation vary with urbanization?We found evidence for local adaptation for both white clover and rhizobia, with stronger signatures of local adaptation for rhizobia than white clover (Q1). While N addition positively affected plant biomass and negatively affected nodule density, N addition did not consistently mediate patterns of local adaptation (Q2). The strength of local adaptation was positively related between white clover and rhizobia under N addition, suggesting that soil N mediates coadaptation between white clover and rhizobia (Q3). We did not find a consistent relationship between measures of urbanization and local adaptation (Q4). Additionally, fitness responses for white clover and rhizobia were unrelated to Rhizobium abundance and local adaptation was unrelated to the broader bacterial microbiome in the soil inoculants or root endosphere.Synthesis. Our results show a spatial mosaic in local adaptation, with stronger local adaptation for rhizobia than white clover. While urbanization does influence the ecology of plant–microbe interactions, our study suggests urbanization does not disrupt local adaptation and coevolution among mutualists. [ABSTRACT FROM AUTHOR]

Plant species respond to varying plant species diversity and associated changes in their abiotic and biotic environment with changes in their phenotype. However, it is not clear to what degree this phenotypic differentiation is due to genotype diversity within populations or phenotypic plasticity of plant individuals. We studied individuals of 16 populations of the clonal herb Taraxacum officinale grown in plant communities of different species richness in a 17‐year‐old grassland biodiversity experiment (Jena Experiment). We collected 12 individuals in each population to measure phenotypic traits and identify distinct genotypes using microsatellite DNA markers. Plant species richness did not influence population‐level genotype and trait diversity. However, it affected the expression of several phenotypic traits, e.g. leaf and inflorescence number, maximum leaf length and seed mass, which increased with increasing plant species richness. Moreover, population‐level trait diversity correlated positively with genotype richness for leaf dry matter content (LDMC) and negatively with inflorescence number. For several traits (i.e. seed mass, germination rate, LDMC, specific leaf area (SLA)), a larger portion of variance was explained by genotype identity, while variance in other traits (i.e. number of inflorescences, leaf nitrogen concentration, leaf number, leaf length) resided within genotypes and thus was mostly due to phenotypic plasticity. Overall, our findings show that plant species richness positively affected the population means of some traits related to whole‐plant performance, whose variation was achieved through both phenotypic plasticity and genotype composition of a population. [ABSTRACT FROM AUTHOR]

Understanding how tropical forests respond to abiotic environmental changes is critical for preserving biodiversity, mitigating climate change, and maintaining ecosystem services in the coming century. To evaluate the relative roles of the abiotic environment and human disturbance on Central African tree community composition, we employ tree inventory data, remotely sensed climatic data, and soil nutrient data collected from 30 1‐ha plots distributed across a large‐scale observational experiment in forests that had been differently impacted by logging and hunting in northern Republic of Congo. We show that the composition of Afrotropical plant communities at this scale responds to human disturbance more than to climate, with particular sensitivities to hunting and distance to the nearest village (a proxy for other human activities, including tree‐cutting and gathering). These findings contrast neotropical predictions, highlighting the unique ecological, evolutionary, and anthropogenic history of Afrotropical forests. [ABSTRACT FROM AUTHOR]

Across animal systems, abiotic environmental features, including timing of seasonal events and weather patterns, affect fitness. An individual's degree of social integration also has fitness consequences, but we lack an understanding of how abiotic features relate to patterns of individual sociality. A deeper understanding of this relationship could be developed from studying systems where these two links with fitness have already been identified. We explored the relationship between individual social behavior and seasonal timing, seasonal length, and weather patterns. We used social network analysis on a sixteen-year dataset of a wild population of hibernating yellow-bellied marmots (Marmota flaviventer). We fit a series of generalized linear mixed models and found that longer growing seasons before winter hibernation and longer winters were associated with increased individual sociality in the following spring. However, later snowmelt was associated with decreased sociality that spring. We found no relationship between individual sociality and various measures of precipitation and temperature. This suggests that seasonal timing and length may be a more important driver of sociality than weather patterns in this system, both as a lag and contemporary effect. Seasonal timing and length may mediate the opportunity or intensity of social interactions. The entwined relationships between the seasonal schedule and weather, and the seemingly contradictory role of winter length and snowmelt, suggests the timing of seasons and its relationship with sociality is complex and further exploration of environment-sociality relationships is required across taxa. Significance statement: While the adaptive benefits of social behavior are well studied, less is known about how features of the abiotic environment drive variation in individual social behavior. Given increasing stochasticity in the timing of seasonal events and weather patterns, mapping the environment-sociality relationship will provide important insights to the drivers of sociality in the wild. This is particularly salient for species most vulnerable to climate and environmental change, such as seasonal hibernators, like yellow-bellied marmots (Marmota flaviventer). We found that features of seasonal duration were positively associated with increased sociality, whereas the timing of seasonal onset was negatively associated. This work provides empirical evidence towards an important gap in the behavioral ecology literature. [ABSTRACT FROM AUTHOR]

Our understanding of plant functional trait variation among populations and how this relates to local adaptation to environmental conditions is largely shaped by above‐ground traits. However, we might expect below‐ground traits linked to resource acquisition and conservation to vary among populations that experience different environmental conditions. Alternatively, below‐ground traits might be highly plastic in response to growing conditions, such as availability of soil resources and association with symbiont arbuscular mycorrhizal fungi (AMF).We assessed (i) the strength of among‐population variation in above‐ and below‐ground traits, (ii) the effects of growing conditions on among‐population variation and (iii) whether variation among populations is linked to source environment conditions, in a globally distributed perennial Plantago lanceolata. Using seeds from 14 populations across three continents, we grew plants in a common garden experiment and measured leaf and root traits linked to resource acquisition and water conservation. We included two sets of experimental treatments (high or low water availability; with and without AMF inoculation), which enabled us to assess trait responses to growing conditions.Across treatments, the percentage of root trait variation explained by populations and continents was 9%–26%, compared to 7%–20% for leaf trait variation. From principal component analysis (PCA), the first PC axis for both root and leaf traits largely reflected plant size, while the second PC broadly captured mass allocation. Root mass allocation (PC 2) was related to mean annual temperature and mean moisture index, indicating that populations from cooler, wetter environments had longer, thinner roots. However, we found little support for a relationship between source environment and leaf trait PCs, root system size (PC1) or individual traits. Water availability and AMF inoculation effects on size were consistent among populations, with larger plants under AMF inoculation, and less mass allocation to leaves under lower water availability.Plantago lanceolata shows substantial population‐level variation in a suite of root traits, but that variation is only partially linked to the source environmental variables studied. Despite considerable differences in source abiotic environments, geographically separated populations have retained a strong and similar capacity for phenotypic plasticity both above and below‐ground. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

In this paper, we redefine the target of evolutionary explanations by proposing the "evosystem" as an alternative to populations, lineages and species. Evosystems account for changes in the distribution of heritable variation within individual Darwinian populations (evolution by natural selection, drift, or constructive neutral evolution), but also for changes in the networks of interactions within or between Darwinian populations and changes in the abiotic environment (whether these changes are caused by the organic entities or not). The evosystem can thereby become a centerpiece for a redefined evolutionary science, that is, evolutionary studies, that apprehends through a single framework the variety of evolutionary processes that lie at various scales. To illustrate the importance of this broadened perspective on evolution, we use a case of antimicrobial resistance evolution: the spread of the blaNDM gene family and the related resistance to carbapenem antibiotics observed globally, and show how evolutionary studies can contribute to answering contemporary socially relevant challenges. [ABSTRACT FROM AUTHOR]

Introduction: For a sustainable forest management adapted to climate change, the use of reproductive forest materials appropriate to the climatic conditions of the planting site is essential. There is a long tradition of testing trees in comparative field trials of provenances, initially with the aim of establishing the best seed sources for plantations, based on the balance between productivity and adaptation. The beech (Fagus sylvatica L.) is the most widespread species of deciduous tree in Europe, and in Romania it is the most important species in terms of area - 31% of the entire forest fund. Trees can adapt to climate change through phenotypic plasticity, defined as the ability of individuals to change their phenotype in response to their environment. Growth and morphology are key characteristics of juvenile trees, important in selection as future trees for quality timber production. The present study analyzed the influence on survival, growth and morphology of juvenile beech trees of: (1) the test site conditions (abiotic environment), (2) the genetic differences between populations, i.e. between trees of different origins and (3) the way in which they are connected with the environment and climate of the place of origin of the provenances. Materials and methods: As seed sources were used 12 beech populations, planted in 2010 and transfered in 2013 in two field tests – Tomnatic and Vidra; a total of 3888 of saplings were planted. In each culture, characteristics associated with survival, growth and morphology were measured, and in the Tomnatic field test also phenology. Each individual diameter was measured 2 cm from the ground using an electronic caliper, and the total height from the ground to the top using a telescopic ruler. Trunk shape was visually assessed according to a 3-class classification, while crown shape on a 4-class scale. Phenological observations were carried out in six stages. Mixed effects models were used in the analysis of variance and the population differentiation was determined based on their variances. Relationships between juvenile tree phenotypes and environmental factors at the provenance location were analyzed with simple linear models between population random effects derived from analyzes of variance and environmental variables at the original provenance location. Results: Survival was higher in Tomnatic than in Vidra, diameter was greater in Tomnatic than in Vidra (both for 2022 and 2023 measurement years), and height was greater in Vidra field test than in Tomnatic field test in 2022 and was undifferentiated in 2023. Diameter growth was greater in Tomnatic than in Vidra, while height growth were less in Tomnatic than in Vidra. In the case of morphological phenotypic characteristics, the Tomnatic field test had more forked trees and more trees with crowns of silvicultural value than Vidra. We recorded population differentiation (Qst > 3) for the first two phenophases (dormant buds closed and onset of bud swelling). Among the traits, diameter, some phenophases and crown shape were linked to climatic factors at the place of origin of the provenances. Discussion: The results showed that the development and quality of juvenile beech trees were influenced by the planting environment, although no clear trend was observed between the two field tests. Trees have significantly larger diameters and better crowns in the higher elevation field test, but lower heights and more stem bifurcation than in the lower elevation field test. Our results partially support previous results regarding the potential for phenotypic plasticity, meaning that similar genotypes have the ability to display different phenotypes in different environments. In our study we found support for phenological plasticity, which is a good indicator of adaptive genetic variation to the beech tree; most studies on tree phenology have shown that these traits are highly differentiated due to adaptive tradeoffs. Our results, the correlations of random effects with climatic factors, indicated that one growth trait - phenology and one morphological - crown shape - showed climate-driven population variations. Conclusions: Population variations suggest a rich reservoir of genetically diverse beech populations in the Romanian Carpathians. Young tree growth and morphology is influenced by test site conditions (abiotic environment), but none of the field test sites could fully account for this. Population differentiation and phenotypic plasticity were found for the first two phenophases of juvenile beech trees. The relationship with the environmental characteristics at the place of origin of the provenances was determined by both temperature (two phenological characteristics) and precipitation (two growth traits and one morphological). [ABSTRACT FROM AUTHOR]

Many plant species can exhibit remarkable variation in leaf characteristics, depending on their abiotic and biotic environment. Environmental changes therefore have the potential to alter leaf traits, which in turn scale up to influence ecosystem processes including net primary productivity, susceptibility to fire, and palatability to herbivores. It is not well understood how consistent trait–environment relationships are among species, across sites and over time. This presents a fundamental challenge for functional ecology, because no study can measure all relevant species in all places at all times. Thus, understanding the limits of transferability is critical. We collected leaf trait measurements on 13 species of grass (family: Poaceae) across 11 sites and five years (n = 3091 individuals). Sites were arrayed along a spatial precipitation gradient in coastal northern California (annual precipitation of 590–1350 mm) with substantial interannual precipitation variability (from 60% below the 30‐year average to 100% above average). Temporal and spatial linear relationships between precipitation and specific leaf area (SLA) appear at first idiosyncratic, with each species sometimes displaying positive and sometimes negative responses. However, this variation arises from sampling different portions of an underlying hump‐shaped relationship, which was shared across most species. This hump‐shaped relationship was driven primarily by changes in leaf tissue density. These results suggest the potential for transferability among species, as well as between space and time, as long as the gradients are sufficiently long to capture the nonlinear response. Future work could explore the physiological basis of the nonlinear SLA response, including the possibility that distinct physiological mechanisms are operating at the two extremes of the gradient. [ABSTRACT FROM AUTHOR]

In highly seasonal systems, the emergence of planktonic resting stages from the sediment is a key driver for bloom timing and plankton community composition. The termination of the resting phase is often linked to environmental cues, but the extent to which recruitment of resting stages is affected by climate change remains largely unknown for coastal environments. Here we investigate phyto- and zooplankton recruitment from oxic sediments in the Baltic Sea in a controlled experiment under proposed temperature and light increase during the spring and summer. We find that emergence of resting stage differs between seasons and the abiotic environment. Phytoplankton recruitment from resting stages were high in spring with significantly higher emergence rates at increased temperature and light levels for dinoflagellate and cyanobacteria than for diatoms, which had highest emergence under cold and dark conditions. In comparison, hatching of copepod nauplii was not affected by increased temperature and light levels. These results show that activation of plankton resting stages are affected to different degrees by increasing temperature and light levels, indicating that climate change affects plankton dynamics through processes related to resting stage termination with potential consequences for bloom timing, community composition and trophic mismatch. [ABSTRACT FROM AUTHOR]

Premise: Astragalus (Fabaceae), with more than 3000 species, represents a globally successful radiation of morphologically highly similar species predominant across the northern hemisphere. It has attracted attention from systematists and biogeographers, who have asked what factors might be behind the extraordinary diversity of this important arid‐adapted clade and what sets it apart from close relatives with far less species richness. Methods: Here, for the first time using extensive phylogenetic sampling, we asked whether (1) Astragalus is uniquely characterized by bursts of radiation or whether diversification instead is uniform and no different from closely related taxa. Then we tested whether the species diversity of Astragalus is attributable specifically to its predilection for (2) cold and arid habitats, (3) particular soils, or to (4) chromosome evolution. Finally, we tested (5) whether Astragalus originated in central Asia as proposed and (6) whether niche evolutionary shifts were subsequently associated with the colonization of other continents. Results: Our results point to the importance of heterogeneity in the diversification of Astragalus, with upshifts associated with the earliest divergences but not strongly tied to any abiotic factor or biogeographic regionalization tested here. The only potential correlate with diversification we identified was chromosome number. Biogeographic shifts have a strong association with the abiotic environment and highlight the importance of central Asia as a biogeographic gateway. Conclusions: Our investigation shows the importance of phylogenetic and evolutionary studies of logistically challenging "mega‐radiations." Our findings reject any simple key innovation behind high diversity and underline the often nuanced, multifactorial processes leading to species‐rich clades. [ABSTRACT FROM AUTHOR]

Premise: The soil microbiome plays a role in plant trait expression and fitness, and plants may be locally adapted or maladapted to their soil microbiota. However, few studies of local adaptation in plants have incorporated a microbial treatment separate from manipulations of the abiotic environment, so our understanding of microbes in plant adaptation is limited. Methods: Here we tested microbial effects on local adaptation in four paired populations of an abundant alpine plant from two community types, dry and moist meadow. In a 5‐month greenhouse experiment, we manipulated source population, soil moisture, and soil microbiome and measured plant survival and biomass to assess treatment effects. Results: Dry meadow populations had higher biomass than moist meadow populations at low moisture, demonstrating evidence of local adaptation to soil moisture in the absence of microbes. In the presence of microbes, dry meadow populations had greater survival than moist meadow populations when grown with dry meadow microbes regardless of moisture. Moist meadow populations showed no signs of adaptation or maladaptation. Conclusions: Our research highlights the importance of microbial mutualists in local adaptation, particularly in dry environments with higher abiotic stress. Plant populations from environments with greater abiotic stress exhibit different patterns of adaptation when grown with soil microbes versus without, while plant populations from less abiotically stressful environments do not. Improving our understanding of the role microbes play in plant adaptation will require further studies incorporating microbial manipulations. [ABSTRACT FROM AUTHOR]

Sediment bypassing connects the upstream and downstream regions of dam impoundments through tunnels and is expected to partly restore natural processes (flood pulse and sediment regime) in dam‐altered river ecosystems. However, few reports examined the effects of restoration on stream biota. We examined the effectiveness of repeated sediment bypassing (12 times) over a period of 5 years in a Japanese dammed river using a before‐after‐reference‐impact design. We compared the abiotic parameters (water quality and substrate environment), biotic assemblages (algae, macroinvertebrates, and fish), and similarities between the dam downstream and undammed reference reaches. The reference sites exhibited high temporal variability in abiotic environments and species composition over the 5‐year period. Most abiotic and biotic parameters downstream of the dam improved and approached those of the changing reference states. However, these indices returned to pretrial conditions after the last trial. Biotic similarities between the downstream and reference reaches gradually increased throughout successive sediment‐bypassing trials for macroinvertebrates and algae; however, these similarities diminished after the last trial. Conversely, the abundance‐based composition of fish assemblages in the restored reach consistently diverged from that of the reference conditions throughout the study period. Our results show that the success and failure of restoration by sediment bypassing may be affected by the amount of bedload in the flushing flows and other regional processes such as migratory connectivity. Sediment bypassing can partially re‐establish natural processes and is a useful tool for improving sediment‐associated environments and biota. [ABSTRACT FROM AUTHOR]

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In this study, we aimed to document the freshwater symbiotic interactions along with the impact of the abiotic environment and anthropogenic effects on the functionality of freshwater organisms. Symbiotic green hydra (Z) and free-living brown hydra (S), either separately or both species together, were treated with the herbicide norflurazon in concentrations of 2 × 10−6 mol/L (N6) and 2 × 10−7 mol/L (N7) for 72 h. Also, hydras were treated with both norflurazon and UV radiation at a wavelength of 254 nm for 2 min or were irradiated only. The next part of the experiment was performed in the same way but with added suspensions of isolated endosymbiotic alga, free-living alga, or both algae together. Mortality, migration, tentacle and tissue damage, changes in the thickness of the mesoglea of hydras, and clustering of algae were monitored. Green hydra generally showed lower rates of migration, and mortality was observed only in green hydra exposed to UV radiation. Tentacle damage was more pronounced in green hydra and included a specific fork-like structure. The use of cryofixation and TEM enabled us to partly elucidate the effect of clustering of algae. In summary, our study provides new insights into the influence of different environmental stressors and their combination on symbiotic and free-living freshwater hydras and algae and a better understanding of interactions in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Inbreeding results from matings between relatives and often leads to a reduction in the fitness of inbred offspring, known as inbreeding depression. There is substantial variation in the magnitude of inbreeding depression among and within species, driven by differences in the biotic and abiotic environment. Recent studies in three species found that parental care has the potential to buffer against inbreeding depression in the offspring, but the generality of this pattern is still unknown. Here, we performed a meta-analysis to test whether variation in the magnitude of inbreeding depression is related to among-species differences in parental care in fishes. We synthesized 536 effect sizes across 56 studies and 18 species, spanning 47 years of research. We found that inbred offspring suffer a smaller reduction in fitness in species that provide biparental care than in species with uniparental or no care. By using a comparative approach, this study provides novel insights into the capacity of parental care to moderate inbreeding depression and suggests that these effects may currently be underappreciated. Considering the potential effects of parental care on inbreeding depression can help us understand why some species avoid inbreeding, whereas others tolerate or even prefer inbreeding, which has important implications for the maintenance of genetic variation within populations. [ABSTRACT FROM AUTHOR]

Changes in telomere length are increasingly used to indicate species' response to environmental stress across diverse taxa. Despite this broad use, few studies have explored telomere length in plants. Thus, evaluation of new approaches for measuring telomeres in plants is needed. Rapid advances in sequencing approaches and bioinformatic tools now allow estimation of telomere content from whole‐genome sequencing (WGS) data, a proxy for telomere length. While telomere content has been quantified extensively using quantitative polymerase chain reaction (qPCR) and WGS in humans, no study to date has compared the effectiveness of WGS in estimating telomere length in plants relative to qPCR approaches. In this study, we use 100 Populus clones re‐sequenced using short‐read Illumina sequencing to quantify telomere length comparing three different bioinformatic approaches (Computel, K‐seek and TRIP) in addition to qPCR. Overall, telomere length estimates varied across different bioinformatic approaches, but were highly correlated across methods for individual genotypes. A positive correlation was observed between WGS estimates and qPCR, however, Computel estimates exhibited the greatest correlation. Computel incorporates genome coverage into telomere length calculations, suggesting that genome coverage is likely important to telomere length quantification when using WGS data. Overall, telomere estimates from WGS provided greater precision and accuracy of telomere length estimates relative to qPCR. The findings suggest WGS is a promising approach for assessing telomere length and, as the field of telomere ecology evolves, may provide added value to assaying response to biotic and abiotic environments for plants needed to accelerate plant breeding and conservation management. [ABSTRACT FROM AUTHOR]

The article "Impact of Abiotic Factors on Occurrence of Capsule Borer and Sucking Pests in Sesamum" examines the relationship between weather factors and the population dynamics of capsule borer and sucking pests in sesame crops. The study, conducted in Andhra Pradesh, India, found that the incidence of capsule borer was influenced by maximum temperature and relative humidity, with peak occurrence in the 9th and 11th weeks. Leafhopper and whitefly populations were also affected by temperature and humidity. This research provides valuable insights into the impact of abiotic factors on pest populations in sesame crops. [Extracted from the article]

Petroleum hydrocarbon (PH) pollution has mostly been caused by oil exploration, extraction, and transportation activities in colder regions, particularly in the Arctic and Antarctic regions, where it serves as a primary source of energy. Due to the resilience feature of nature, such polluted environments become the realized ecological niches for a wide community of psychrophilic hydrocarbonoclastic bacteria (PHcB). In contrast, to other psychrophilic species, PHcB is extremely cold-adapted and has unique characteristics that allow them to thrive in greater parts of the cold environment burdened with PHs. The stated group of bacteria in its ecological niche aids in the breakdown of litter, turnover of nutrients, cycling of carbon and nutrients, and bioremediation. Although such bacteria are the pioneers of harsh colder environments, their growth and distribution remain under the influence of various biotic and abiotic factors of the environment. The review discusses the prevalence of PHcB community in colder habitats, the metabolic processes involved in the biodegradation of PH, and the influence of biotic and abiotic stress factors. The existing understanding of the PH metabolism by PHcB offers confirmation of excellent enzymatic proficiency with high cold stability. The discovery of more flexible PH degrading strategies used by PHcB in colder environments could have a significant beneficial outcome on existing bioremediation technologies. Still, PHcB is least explored for other industrial and biotechnological applications as compared to non-PHcB psychrophiles. The present review highlights the pros and cons of the existing bioremediation technologies as well as the potential of different bioaugmentation processes for the effective removal of PH from the contaminated cold environment. Such research will not only serve to investigate the effects of pollution on the basic functional relationships that form the cold ecosystem but also to assess the efficacy of various remediation solutions for diverse settings and climatic conditions. [ABSTRACT FROM AUTHOR]

Plants use substrate-borne vibrations to interact with both biotic and abiotic factors in their environment. Substrate-borne vibrations play a key role in the detection of herbivory and the interactions between plants and pollinators. More than 150 000 species of arthropods, including major pests and carnivores, use plant-borne vibrations for communication, prey detection, and mating. Biological pest control involves using living organisms to suppress pest populations. The ecology of fear relates to predator-induced behavior and physiology-mediated costs for prey. There is overwhelming evidence that synthetic pesticides have a negative impact on the environment and human health, emphasizing the need for novel and sustainable methods for plant protection. A growing body of literature reports that plants interact through substrate-borne vibrations with arthropod pests and mutualistic arthropods that provide biological control and pollination services. Here, we propose a new theoretical framework that integrates insights from biological control, the ecology of fear, and plant-borne vibrations, to address plant–insect interactions and explore new, sustainable opportunities to improve plant health and productivity. [ABSTRACT FROM AUTHOR]

Urban environments often contain mosquito species that are responsible for transmitting medically important pathogens to humans. Large disturbance events, like hurricanes, can devastate large urban areas, especially in the tropics, however little data exist for how these storms affect vector populations. During September 2017 Hurricanes Irma (category 5) and Maria (category 4) passed in proximity to the island of Puerto Rico, USA, causing significant damage to the built environment and significantly altering the abiotic environment including the removal of the plant canopy. We measured adult Aedes aegypti populations, the main vector of several pathogens, and larval containers across eight neighborhoods in San Juan, the capitol, that varied in socioeconomic status (SES) across eight sampling periods over 17 months following the storms. We also analyzed the nutrient content (%N, %C, C:N) and stable isotopes (δ15N, δ13C) from adults and isotopes from containers to assess how the nutrient environments changed post hurricanes. Mosquito population sizes were invariant throughout sampling, although more females were collected in lower SES neighborhoods that were more enriched in δ15N compared to higher SES locations. We did find that the storms altered the stoichiometric content of adults, with lower C:N values right after compared to a year later; larval containers showed an increase in δ15N through time. The lack of any interactive effects of the storms on specific neighborhoods suggests that Irma and Maria affected all locations equally, however, the storms altered the nutrient content of both adults and larval containers, a result with implications for pathogen transmission. [ABSTRACT FROM AUTHOR]

While urbanization is often associated to a loss of biodiversity, non-native animal species are strikingly successful in urban landscapes. As biological invasions are recognized to have detrimental environmental, social and economic impacts, extensive understanding of the interactions between invasive species and the abiotic and biotic environment is necessary for effective prevention and management strategies. However, the mechanisms underlying the success of invasive animals in urban environments are still poorly understood. We provide a first conceptual review of the role of urbanization in the introduction, establishment, and potential spread of non-native animal species. We summarize and discuss the mechanisms enhancing biological invasive potential of non-native animals in urban environments, by both isolating and interlinking the abiotic and biotic drivers involved. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA 2020) process, this systematic review covers a total of 124 studies comprehensive of all taxonomic groups, albeit with an evident publication bias for avian and terrestrial invertebrate species (22.1% and 19.8% of literature respectively). High-income regions also represent a larger bulk of the literature (Europe: 26.7%, North America: 23.7%). The most common reported factors facilitating species invasions in urban areas are reduced biotic resistance, and the competitive and urban-compatible ecological and/or behavioural traits of non-native animals allowing urban exploitation and aiding invasion. Finally, we identify important knowledge gaps, such as the scarcity of studies investigating socio-economic spatial patterns in the presence and abundance of invasive species, as well as the adaptive evolution of non-native animal species in urban areas. [ABSTRACT FROM AUTHOR]

The binning of species into categorical and artificial functional groups has often been used in ecology to overcome data deficiencies with the expectation that these deficiencies and, therefore, groups will fade. Other influential work has argued that functional groups naturally arise in tree communities due to a diffuse competitive environment and a largely uniform abiotic environment leading to functional convergence. The pragmatic usage and biological arguments for functional groups have clear limitations that may make them dubious. The development of public functional trait repositories and future trait collection campaigns in undersampled regions will reduce some reliance on functional groups, but the conceptual framework underlying functional groups related to shade tolerance could be modified to include additional complexity relating to pest and pathogen interactions to result in more realistic and defendable insights into the generation and maintenance of tree biodiversity. Functional trait variation measured on continuous scales has helped ecologists to unravel important ecological processes. However, forest ecologists have recently moved back toward using functional groups. There are pragmatic and biological rationales for focusing on functional groups. Both of these approaches have inherent limitations including binning clearly continuous distributions, poor trait-group matching, and narrow conceptual frameworks for why groups exist and how they evolved. We believe the pragmatic use of functional groups due to data deficiencies will eventually erode. Conversely, we argue that existing conceptual frameworks for why a limited number of tree functional groups may exist is a useful, but flawed, starting point for modeling forests that can be improved through the consideration of unmeasured axes of functional variation. [ABSTRACT FROM AUTHOR]

In this study, the research material is represented by coleopteran species found in a mixed forest In this study, the research material is represented by beetle species found in a mixed forest composed of deciduous and coniferous tree species, covering an area of 8 hectares. The forest is located in an area with rich biodiversity, characterized by a natural succession of tree species and a varied pitfall, which is conducive to the development of diverse fauna. This paper focuses on analyzing the structure, dynamics, abundance, and ecological role of beetles within this forest ecosystem, emphasizing their interactions with other species and the abiotic environment. The collection of fauna was carried out using pitfall traps type Barber, which are ecological traps, during the year 2024, from July to September, over a period of three months. A total of 6 traps were installed at various marked locations in the forest, depending on vegetation density, to adequately cover habitat diversity. The material from the traps was collected at regular intervals of 10-14 days to monitor the activity of beetle species. Throughout the study, 6 collections of entomological material were conducted on the following dates: July 10, July 22, July 31, August 14, August 28, and September 11. Among the most frequently collected species are Poecilus cupreus, Necrophorus vespillo, Geotrupes vernalis, Aptinus bombarda, and Silpha carinata. These species have a significant ecological impact on the ecosystem, playing key roles in organic matter decomposition and nutrient recycling, pollination processes, and controlling populations of harmful insects. Additionally, some of these species may be classified as harmful fauna in certain contexts, having the potential to affect the natural balance of other insect species or even the vegetation. However, overall, the majority of the beetle species collected in this study have a beneficial role and are essential for maintaining the health of the analyzed forest ecosystem. [ABSTRACT FROM AUTHOR]

Plant iron (Fe) nutrition and metabolism is a fascinating and challenging research topic; understanding the role of Fe in the life cycle of plants requires knowledge of Fe chemistry and biochemistry and their impact during development. Plant Fe nutritional status is dependent on several factors, including the surrounding biotic and abiotic environments, and influences crop yield and the nutritional quality of edible parts. The relevance of plant Fe research will further increase globally, particularly for Africa, which is expected to reach 2.5 billion people by 2050. The aim of this review is to provide an updated picture of plant Fe research conducted in African countries to favor its dissemination within the scientific community. Three main research hotspots have emerged, and all of them are related to the production of plants of superior quality, i.e., development of Fe-dense crops, development of varieties resilient to Fe toxicity, and alleviation of Fe deficiency, by means of Fe nanoparticles for sustainable agriculture. An intensification of research collaborations between the African research groups and plant Fe groups worldwide would be beneficial for the progression of the identified research topics. [ABSTRACT FROM AUTHOR]

Classical molecular and lattice dynamics were applied to explore the structure and dynamics of water on different surfaces of vaterite, the least abundant calcium carbonate polymorph. Surfaces were generated starting from the three possible structural models for vaterite (monoclinic, hexagonal/trigonal, and triclinic) and pre-screened using their surface energies in an implicit solvent. Surfaces with energies lower than 0.55 J/m2 were then run in explicit water. The majority of these surfaces dissolve in less than 100 ns, highlighting the low stability of this phase in abiotic environments. Three stable surfaces were identified; they exhibited only minor structural changes when in contact with explicit water and did not show any tendency to dissolve during 1 µs molecular dynamics simulations. The computed water density profiles show that all these surfaces have two distinct hydration layers. The water residence time at the various calcium sites was computed to be within 0.7 and 20.5 ns, which suggests that specific Ca ions will be more readily available to bind with organic molecules present in solution. This analysis is a step forward in understanding the structure of this complex mineral and its role in biomineralization, as it provides a solid theoretical background to explore its surface chemistry. In particular, this study provides realistic surface models and predicts the effect of water exchange at the surface active sites on the adsorption of other molecules. [ABSTRACT FROM AUTHOR]

Introduction: Leptospirosis is zoonotic disease that transmits via natural transmission from vertebrate animals to human beings and vice versa. This disease is caused by an infection of the Leptospira sp. bacterium. It is estimated that there are 1 million cases of Leptospirosis that attack humans worldwide with 60 thousand deaths per year. In Indonesia, such cases and death rates have fluctuated. In 2021, there was a decrease in cases, but the CFR rate increased from 9.1% to 11.4%. Leptospirosis cases become endemic in many countries, especially in tropical and subtropical areas with high rainfall, especially in settlements with poor environmental conditions. Based on previous research, there were differences in the results between several research variables with the incidence of Leptospirosis. This gap underlies the writing of this article to bring together the existing results. Discussion: This study used literature review method for research articles on biotic and abiotic environmental risk factors with Leptospirosis in settlements sourced from scientific publication websites. After going through these stages, 14 final full text articles were obtained. The data used were research studies conducted from January 2018 to April 2023. The articles found show that environmental factors are closely related to the incidence of Leptospirosis in settlements. Conclusion: The variable abiotic environment factors associated with the occurrence of Leptospirosis are temperature, pH, the presence of sewers and puddles. The presence of rats and the presence of animals or livestock are related to biotic environmental factors.

This article is an editorial for a thematic issue on Polar and Alpine Microbiology in the journal FEMS Microbiology Ecology. The issue focuses on the microbial ecology of cold habitats and the importance of understanding the biodiversity and functional roles of microorganisms in these environments. The issue includes 30 peer-reviewed papers, most of which were presented at the 9th International Conference on Polar and Alpine Microbiology (PAM22). The papers cover a range of topics, including microbial communities, adaptation, carbon and nitrogen turnover, and plant-microbe interactions, with a particular emphasis on Arctic, mountain, and Antarctic regions. The issue is dedicated to the late researcher S. Craig Cary, who made significant contributions to the study of microbial life in extreme environments. [Extracted from the article]

Simple Summary: The gut bacterial community of two captive ducks was investigated in this study across seasons. It was discovered that the composition of gut bacteria was significantly affected by seasonal variations, with greater diversity in winter. Different seasons yielded different biomarkers, with the majority found in winter when a more intricate bacterial network structure was seen. Ten important pathogenic bacterial species were discovered and appeared to be more abundant in the summer. The presence of significant pathogenic bacteria was demonstrated by this study, raising concerns for captive animals, and shedding light on how gut bacterial composition is affected by seasonal fluctuations. Vertebrates and their gut bacteria interact in complex and mutually beneficial ways. The intestinal microbial composition is influenced by several external influences. In addition to food, the abiotic elements of the environment, such as temperature, humidity, and seasonal fluctuation are also important determinants. Fecal samples were collected from two captive duck species, Baikal teal (Sibirionetta formosa) and common teal (Anas crecca) across four seasons (summer, autumn, winter, and spring). These ducks were consistently fed the same diet throughout the entire experiment. High throughput sequencing (Illumina Mi-seq) was employed to analyze the V4–V5 region of the 16sRNA gene. The dominant phyla in all seasons were Proteobacteria and Firmicutes. Interestingly, the alpha diversity was higher in winter for both species. The NMDS, PCoA, and ANOSIM analysis showed the distinct clustering of bacterial composition between different seasons, while no significant differences were discovered between duck species within the same season. In addition, LefSe analysis demonstrated specific biomarkers in different seasons, with the highest number revealed in winter. The co-occurrence network analysis also showed that during winter, the network illustrated a more intricate structure with the greatest number of nodes and edges. However, this study identified ten potentially pathogenic bacterial species, which showed significantly enhanced diversity and abundance throughout the summer. Overall, our results revealed that season mainly regulated the intestinal bacterial community composition and pathogenic bacteria of captive ducks under the instant diet. This study provides an important new understanding of the seasonal variations in captive wild ducks' intestinal bacterial community structure. The information available here may be essential data for preventing and controlling infections caused by pathogenic bacteria in captive waterbirds. [ABSTRACT FROM AUTHOR]

In 1959, the plant community and abiotic environment of three 2.2-ha Chihuahuan Desert plots were studied in Big Bend National Park, Texas. In 2019 and 2020, we continued the study of these plots using the same methods with the goal of evaluating the long-term trends in the perennial plant communities of 3 different habitats within the park. Our study assessed species composition, density, and ground cover, which were compared with the same parameters reported from 1959. At a rocky site in the foothills of the Chisos Mountains, plant density decreased during the 61 years of the study (1959–2020) but remained high compared with the other sites. Many of the perennial plant species persisted, but the relative proportions of some species had changed over time. Another study plot was situated on a gently sloping alluvial fan at Panther Junction. Plant density and ground cover increased substantially on this desert pavement habitat. Much of the increased density can be attributed to grasses, particularly Lehmann lovegrass (Eragrostis lehmanniana), an exotic invasive species likely introduced as a result of human activity surrounding the nearby park headquarters at Panther Junction. A third plot was a level sandy habitat on Tornillo Flat. The density and species composition of the plant community at Tornillo Flat were remarkably stable between the 1959 and 2019 surveys. Factors likely affecting the plant community at the 3 plots include periodic drought, invasive species, fire, climate change, and secondary succession following past overgrazing of livestock that ended with the establishment of the national park in 1944. [ABSTRACT FROM AUTHOR]

Metabolic network models have become increasingly precise and accurate as the most widespread and practical digital representations of living cells. The prediction functions were significantly expanded by integrating cellular resources and abiotic constraints in recent years. However, if unreasonable modeling methods were adopted due to a lack of consideration of biological knowledge, the conflicts between stoichiometric and other constraints, such as thermodynamic feasibility and enzyme resource availability, would lead to distorted predictions. In this work, we investigated a prediction anomaly of EcoETM, a constraints-based metabolic network model, and introduced the idea of enzyme compartmentalization into the analysis process. Through rational combination of reactions, we avoid the false prediction of pathway feasibility caused by the unrealistic assumption of free intermediate metabolites. This allowed us to correct the pathway structures of L-serine and Ltryptophan. A specific analysis explains the application method of the EcoETM-like model and demonstrates its potential and value in correcting the prediction results in pathway structure by resolving the conflict between different constraints and incorporating the evolved roles of enzymes as reaction compartments. Notably, this work also reveals the trade-off between product yield and thermodynamic feasibility. Our work is of great value for the structural improvement of constraints-based models. [ABSTRACT FROM AUTHOR]

Competition between aquatic organisms is heavily influenced by abiotic factors in the environment, specifically flow regime in aquatic systems. Flow regime has been shown to significantly affect the way in which a species uses the environmental resources and alterations in flow can exasperate competitive advantages by congenerics. However, little work has concentrated on the competitive outcome between native and invasive organisms as a function of flow regime. Here, we sought to uncover how competition between two crayfish species (the native virile crayfish [Faxonius virilis] and invasive rusty crayfish [Faxonius rusticus]) was affected by varying flow rates. To do this, we size-matched crayfish and quantified three separate behaviors (food use, shelter use, and fights) of crayfish in four different discharge levels (no discharge—0 cm3/s; low discharge—116 cm3/s; intermediate discharge—345 cm3/s; high discharge—450 cm3/s). We found that the number of foraging bouts was significantly (p < 0.001) influenced by discharge levels for both species, where rusty crayfish foraged more often in no and discharge. The number of times crayfish sheltered also varied between species and was significantly (p < 0.001) altered by discharge level, where rusty crayfish sheltered more often in no discharge and virile crayfish sheltered more in low and intermediate discharge levels. Similarly, the number of fights that crayfish engaged in also significantly (p < 0.001) depended upon species and discharge levels. Rusty crayfish engaged in more agonistic activities in no and high discharge levels while virile crayfish participated most often in low and intermediate discharge levels. [ABSTRACT FROM AUTHOR]

Massive quantitities of waste generated by rising human population and rapid urbanisation are often disposed of into open dumps or landfills. The leachates released from these dumpsites penetrate the soil and can alter the existing biotic communities of the soil. In soil, the microbial communities are the dominant drivers which undergo changes in community structure and diversity in response to the changes in their biotic and abiotic environment. The heterogeneous waste disposed in a dumpsite or a landfill releases leachate containing nutrients along with toxic chemicals and allochthonous microorganisms in the soil. How the microbial community structure and diversity changes in a landfill or a dumpsite soil receiving leachate from it are some important questions from the perspective of microbial ecology. To unravel the community structure of bacteria inthe soil receiving dumpsite leachate and to assess the disturbance diversity relationship in this site, a comparative metagenomic analysis of the soil receiving dumpsite leachate and that of the soil of an adjacent wetland (conserved under Ramsar convention) not receiving dumpsite leachate used as the reference point was done to observe the effect of waste dumping activity on microbial diversity. The microbial diversity of the soil receiving dumpsite leachate and that of the wetland soil were found to differ significantly. Higher microbial diversity was observed in the dumpsite soil, while the wetland soil showed relative dominance of a few microbial taxa. [ABSTRACT FROM AUTHOR]

Abiotic stressors threaten the survival mechanism of plant life on Earth. Phytohormones are one of the defensive molecules produced by plants to counteract destructive effects elicited by abiotic stresses. In recent years, melatonin has gained prime importance in plant research because of its regulatory role in abiotic stress tolerance. Melatonin plays a central role in interacting with other phytohormones such as auxin, gibberellin, cytokinin, abscisic acid, ethylene, brassinosteroids, jasmonic acid, salicylic acid and plant growth regulators like nitric oxide, polyamines, γ-aminobutyric acid and serotonin to regulate stress alleviation for maintaining basal growth under harsh environmental conditions. The precise understanding of intricate web of crosstalk mechanisms among different phytohormones and their interconnected networks in terms of synergistic and antagonistic actions is crucial for maintaining cellular dynamics under unfavorable conditions. Therefore, in the present review, we mainly focused on crosstalk regulatory circuits operated by melatonin with other phytohormones at both physiological and molecular levels and their responses under known abiotic stress environment. The biosynthesis, signaling pathway and efficacy of melatonin in various stress avoidance are also enumerated in this review. Indeed, it would not be presumptuous to hope that this review will be helpful for designing climate-smart crop cultivars in the forthcoming years using melatonin as the major stress mitigator and endogenous signaling molecule during stressful situations. [Display omitted] • Biosynthesis of melatonin in plants is more complex than in animals. • Melatonin receptor CAND2/PMTR1 participates in melatonin-mediated signal perception, involving mitogen activated protein kinase-signaling cascades to enhance stress tolerance. • Melatonin interacts with different phytohormones for conferring stress protection. • Melatonin and phytohormones crosstalk operates synergistically or antagonistically, depending on the nature and complexity of stress, plant type and surrounding environment. [ABSTRACT FROM AUTHOR]

Urbanization is changing the conditions in which many species live, forcing them to adjust to these novel environments. Floral size and shape are critical traits for the reproduction of plants pollinated by animals as they are involved in the attraction of pollinators and in efficient pollination. Variation in size and shape could be affected by urbanization via its modification of the abiotic environment (habitat fragmentation, water availability, temperature, soil properties), or via its impact on the biotic environment of plants (pollination, herbivory). Although numerous studies have assessed the impact of urbanization on pollinator communities and many plant traits, few have investigated its impact on floral size and shape while quantifying the proportion of the total urbanization effect that is due to biotic interactions. In this study, we tested if urbanization and pollinator visitation rates affect the flower shape of the spotted jewelweed, Impatiens capensis. We quantified the size and shape of flowers in frontal and profile views using geometric morphometrics for 228 individuals from six populations from the region of Montreal, Canada. Pollinator visitation rates were estimated at each site and the main pollinators were found to be bumblebees, honeybees and hummingbirds. We found that floral size and shape are significantly correlated with urbanization as measured by the amount of vegetation in the surrounding environment of the plants (mean normalized vegetation index, NDVI) and by the visitation rates of bumblebees and honey bees. Partitioning of the total flower shape variation suggests that urbanization affects flower shape through abiotic factors and via its impact on pollinator visitation rates. While further studies from other cities are necessary to confirm the role of urbanization in shaping the floral shape of I. capensis, these results support the idea that urbanization could affect flower shapes. [ABSTRACT FROM AUTHOR]

The expansion of woody species from their historical ranges into grasslands is a global problem. Understanding the mechanisms that enable species to successfully establish and then re‐encroach following their removal is critical to effectively managing problem species. Legacy effects are a mechanism that could be critical to the reestablishment of woody encroachers following their removal. Legacy effects occur when a species alters the biotic and abiotic environment in a way that affects communities that establish subsequently. In this study, we assess whether the eastern redcedar (Juniperus virginiana), a North American woody encroacher, generates legacy effects that affect communities that establish following removal of this species from an experimental grass community. We conducted a series of experiments to evaluate the effects of J. virginiana, roots on the germination and growth of grasses and to determine if the effects of root‐addition treatments were derived from a microbial or allelopathic origin. Aqueous extracts of J. virginiana roots were found to inhibit the germination of grasses. We found escalating suppression of overall community biomass and the biomass of each individual species with increasing root treatments. Finally, we determined the origin of the observed suppressive effect is unlikely to be of microbial origin. Synthesis: Our results suggest that J. virginiana exudes an allelochemical into soils that inhibits the growth of certain grasses and thus has the potential to have legacy effects on future occupants. We suggest that the inhibition of the development of grasses in areas where J. virginiana has been removed is a mechanism that may favor the reestablishment of J. virginiana. Our results indicate the legacy effects of J. virginiana must be considered when conducting removal and restoration of J. virginiana infested lands. [ABSTRACT FROM AUTHOR]

Anthropogenic electromagnetic radiation is an important environmental factor affecting the functionality of biological systems. Sensitivity to various frequencies of electromagnetic radiation has been detected in ixodid ticks in the past. However, the physiological aspects of radiation effects have not yet been studied in ticks. In the presented experiment, 360 Ixodes ricinus ticks, 180 males and 180 females, were divided into 16 irradiated and 8 control groups. The irradiated groups were exposed to two different intensities of electromagnetic radiation with a frequency of 900 MHz at different lengths of exposure time. RT-PCR was utilized to determine the changes in mRNA levels in tick synganglia after irradiation. Four randomly selected neuropeptide genes were tested—allatotropin (at), FGLa-related allatostatins (fgla/ast), kinin, and arginine-vasopressin-like peptide (avpl). A significant decrease in transcript levels in all female groups exposed to higher intensity radiofrequency radiation for 1 to 3 h was found. After one hour of radiofrequency exposure, a significant downregulation in allatotropin expression in males was detected. A consistent downregulation of the at gene was detected in males irradiated with at a higher intensity. Unfortunately, the specific functions of the studied neuropeptides in ticks are not known yet, so a more comprehensive study is necessary to describe the effects of EMF on observed neuropeptides. This study represents the first report on the effects of the abiotic environment on tick neurophysiology. [ABSTRACT FROM AUTHOR]

Plants influence the abiotic and biotic environment of the rhizosphere, affecting plant performance through plant–soil feedback (PSF). We compared the strength of nutrient and microbe-mediated PSF and its implications for plant performance in domesticated and wild grasses with a fully crossed greenhouse PSF experiment using four inbred maize genotypes (Zea mays ssp. mays b58, B73-wt, B73-rth3, and HP301), teosinte (Z. mays ssp. parviglumis), and two wild prairie grasses (Andropogon gerardii and Tripsacum dactyloides) to condition soils for three feedback species (maize B73-wt, teosinte, Andropogon gerardii). We found evidence of negative PSF based on growth, phenotypic traits, and foliar nutrient concentrations for maize B73-wt, which grew slower in maize-conditioned soil than prairie grass-conditioned soil. In contrast, teosinte and A. gerardii showed few consistent feedback responses. Both rhizobiome and nutrient-mediated mechanisms were implicated in PSF. Based on 16S rRNA gene amplicon sequencing, the rhizosphere bacterial community composition differed significantly after conditioning by prairie grass and maize plants, and the final soil nutrients were significantly influenced by conditioning, more so than by the feedback plants. These results suggest PSF-mediated soil domestication in agricultural settings can develop quickly and reduce crop productivity mediated by PSF involving changes to both the soil rhizobiomes and nutrient availability. [ABSTRACT FROM AUTHOR]

Indo-Pacific corals predominantly reproduce using synchronous mass spawning events to maximise fertilisation. However, as disturbances continue to thin population densities, the quantities of gametes released declines and colonies become more isolated, reducing the likelihood of cross-fertilisation. Local hydrodynamic conditions can promote or inhibit gamete contact; thus, the interaction between the abiotic environment and sperm density will determine the amount of time gametes interact. In this study, we investigated the sensitivity of reproduction to manipulations of two key limiting factors of fertilisation: sperm concentration and contact time between gametes. We explored fertilisation kinetics of phylogenetically and functionally similar and diverse coral taxa on the Great Barrier Reef and Western Australia (Acropora digitifera, A. tenuis; Coelastrea aspera, Platygyra daedalea). Results indicate that fertilisation is optimised at sperm concentrations > 103 sperm mL−1 and contact times > 30 s, but the extent of these relationships is species-specific. All species showed clear differences in fertilisation success across contact times, although these differences were less distinct for A. tenuis and P. daedalea at very high sperm concentrations. Acropora digitifera and P. daedalea exhibited nonlinear trends with steep slopes of increased fertilisation success once sperm concentration surpassed values of 104 sperm mL−1 and 102 sperm mL−1, respectively, followed by slight declines. Acropora tenuis and A. digitifera had the highest maximum fertilisation success, likely owing to beneficial evolved functional traits like large egg sizes. The present analysis underpins studies of fertilisation kinetics in natural reef populations to help inform management and restoration practices that assist population resilience and recovery. [ABSTRACT FROM AUTHOR]

Large old trees, which provide ecosystem services and serve as a historical and cultural heritage, are exposed to various environmental threats, such as habitat fragmentation and climate change, necessitating diagnosis of tangible and intangible stresses and their effects on tree growth for effective management. This study investigated the photosynthetic characteristics of 25 large old Zelkova serrata (Thunb.) Makino trees in Chungcheong Province, Korea, and identified the physical environmental factors affecting their physiological responses. Maximum assimilation rate (Amax) was the highest in July (summer), transpiration rate (E) and stomatal conductance (gs) increased from May (spring) to September (fall), and water use efficiency (WUE) was the highest in May (spring) and decreased until September (fall). Amax decreased as tree height increased. Ambient CO2 and vapor pressure deficit (VPD) were negatively correlated with photosynthetic parameters throughout the growth season and in July (summer) and September (fall), respectively. Physical environmental factors exhibited complex effect on physiological activities, which increased with wide growth space and decreased with deep soil covering and high impervious ground surface ratio. Physiological responses differed with surface types within the growth space, with bare land showing higher mean Amax, E, and gs than areas with mulching material or concrete. This study quantitatively determined the physiological activities of large old Z. serrata and proposes appropriate management measures for ensuring their healthy growth in abiotic stress environment. [ABSTRACT FROM AUTHOR]