Search

Summary: Plant pollen is rich in protein, sterols and lipids, providing crucial nutrition for many pollinators. However, we know very little about the quantity, quality and timing of pollen availability in real landscapes, limiting our ability to improve food supply for pollinators.We quantify the floral longevity and pollen production of a whole plant community for the first time, enabling us to calculate daily pollen availability. We combine these data with floral abundance and nectar measures from UK farmland to quantify pollen and nectar production at the landscape scale throughout the year.Pollen and nectar production were significantly correlated at the floral unit, and landscape level. The species providing the highest quantity of pollen on farmland were Salix spp. (38%), Filipendula ulmaria (14%), Rubus fruticosus (10%) and Taraxacum officinale (9%). Hedgerows were the most pollen‐rich habitats, but permanent pasture provided the majority of pollen at the landscape scale, because of its large area. Pollen and nectar were closely associated in their phenology, with both peaking in late April, before declining steeply in June and remaining low throughout the year.Our data provide a starting point for including pollen in floral resource assessments and ensuring the nutritional requirements of pollinators are met in farmland landscapes. [ABSTRACT FROM AUTHOR]

The core principle shared by most theories and models of succession is that, following a major disturbance, plant–environment feedback dynamics drive a directional change in the plant community. The most commonly studied feedback loops are those in which the regrowth of the plant community causes changes to the abiotic (e.g. soil nutrients) or biotic (e.g. dispersers) environment, which differentially affect species availability or performance. This, in turn, leads to shifts in the species composition of the plant community. However, there are many other PE feedback loops that potentially drive succession, each of which can be considered a model of succession. While plant–environment feedback loops in principle generate predictable successional trajectories, succession is generally observed to be highly variable. Factors contributing to this variability are the stochastic processes involved in feedback dynamics, such as individual mortality and seed dispersal, and extrinsic causes of succession, which are not affected by changes in the plant community but do affect species performance or availability. Both can lead to variation in the identity of dominant species within communities. This, in turn, leads to further contingencies if these species differ in their effect on their environment (priority effects). Predictability and variability are thus intrinsically linked features of ecological succession. We present a new conceptual framework of ecological succession that integrates the propositions discussed above. This framework defines seven general causes: landscape context, disturbance and land‐use, biotic factors, abiotic factors, species availability, species performance, and the plant community. When involved in a feedback loop, these general causes drive succession and when not, they are extrinsic causes that create variability in successional trajectories and dynamics. The proposed framework provides a guide for linking these general causes into causal pathways that represent specific models of succession. Our framework represents a systematic approach to identifying the main feedback processes and causes of variation at different successional stages. It can be used for systematic comparisons among study sites and along environmental gradients, to conceptualise studies, and to guide the formulation of research questions and design of field studies. Mapping an extensive field study onto our conceptual framework revealed that the pathways representing the study's empirical outcomes and conceptual model had important differences, underlining the need to move beyond the conceptual models that currently dominate in specific fields and to find ways to examine the importance of and interactions among alternative causal pathways of succession. To further this aim, we argue for integrating long‐term studies across environmental and anthropogenic gradients, combined with controlled experiments and dynamic modelling. [ABSTRACT FROM AUTHOR]

Environmental change is disrupting mutualisms between organisms worldwide. Reported declines in insect populations and changes in pollinator community compositions in response to land use and other environmental drivers have put the spotlight on the need to conserve pollinators. While this is often motivated by their role in supporting crop yields, the role of pollinators for reproduction and resulting taxonomic and functional assembly in wild plant communities has received less attention. Recent findings suggest that observed and experimental gradients in pollinator availability can affect plant community composition, but we know little about when such shifts are to be expected, or the impact they have on ecosystem functioning. Correlations between plant traits related to pollination and plant traits related to other important ecosystem functions, such as productivity, nitrogen uptake or palatability to herbivores, lead us to expect non‐random shifts in ecosystem functioning in response to changes in pollinator communities. At the same time, ecological and evolutionary processes may counteract these effects of pollinator declines, limiting changes in plant community composition, and in ecosystem functioning. Despite calls to investigate community‐ and ecosystem‐level impacts of reduced pollination, the study of pollinator effects on plants has largely been confined to impacts on plant individuals or single‐species populations. With this review we aim to break new ground by bringing together aspects of landscape ecology, ecological and evolutionary plant–insect interactions, and biodiversity–ecosystem functioning research, to generate new ideas and hypotheses about the ecosystem‐level consequences of pollinator declines in response to land‐use change, using grasslands as a focal system. Based on an integrated set of seven hypotheses, we call for more research investigating the putative pollinator‐mediated links between landscape‐scale land use and ecosystem functioning. In particular, future research should use combinations of experimental and observational approaches to assess the effects of changes in pollinator communities over multiple years and across species on plant communities and on trait distributions both within and among species. [ABSTRACT FROM AUTHOR]

Electronic waste (e-waste) illegally disposal in Thailand is becoming more widespread. A sustainable metal recovery technology is needed. A phytotechnology called "phytomining" of metals such as nickel (Ni) is a promising technology providing a sustainable solution to the growing e-waste problems. This study investigated the ability of Acacia species in association with e-waste site isolated, plant growth-promoting rhizobacteria (PGPR), Bacillus amyloliquefaciens. Acacia mangium accumulated higher Ni in their tissues when Ni concentrations in soil were lower than 200 mg kg−1. The inoculation of PGPR B. amyloliquefaciens enhanced Ni uptake and accumulation in the leaves, stem, and root. The results showed that the highest Ni concentration was found in the root ash (825.50 mg kg−1) when inoculated plants were grown in soil containing 600 mg kg−1 Ni. Hence, the Ni recovery process and mass balance were performed on root ashes. The highest Ni recovery was 91.3% from the acid (H2SO4) leachate of the ash of inoculated plant treated with 600 mg kg−1 Ni. This demonstrates the feasibility of PGPR-assisted phytomining from Ni-contaminated soil. Phytomining of Ni from any e-waste contaminated sites using Acacia mangium in combination with B. amyloliquefaciens can promote plant growth and improve the uptake of Ni. Phytomining from electronic waste is an appealing technology that can provide a long-term waste management strategy while valuable trace metals can be recovered. In this study, we evaluated the nickel phytomining ability of Acacia mangium in association with PGPR Bacillus amyloliquefaciens. The results from this study showed that Ni recovery from phytomass using A. mangium with B. amyloliquefaciens can be further improved leading to a sustainable waste management strategy. [ABSTRACT FROM AUTHOR]

The biological reserve of Sidi Boughaba has a unique plant biodiversity, with many animals, including birds, finding refuge there. Data on this biodiversity is old and incomplete. This phytosociological study was carried out to define the vegetation structure of the area. Stratified sampling was carried out and 124 relevés were recorded. Multivariate statistical analyses (correspondence factorial analysis and hierarchical ascending classification) used to process the relevés revealed the presence of 9 plant groups, including 4 plant associations and 5 subassociations, which belong to 3 phytosociological classes (Ammophiletea, Quercetea ilicis and Querco roboris-Fagetea sylvaticae). Quercetea ilicis is the most widespread in the area, showing several successional stages on grey and consolidated dunes. Vegetation of Ammophiletea can only be found on mobile sand. Vegetation of the class Querco roboris-Fagetea sylvaticae occupies an inter-dunar depression on hydromorphic soil. The association Pterido aquilinum-Populetum albae is newly described as five subassociations of Clematido cirrhosae-Juniperetum lyciae. [ABSTRACT FROM AUTHOR]

In the age of big data, scientific progress is fundamentally limited by our capacity to extract critical information. Here, we map fine-grained spatiotemporal distributions for thousands of species, using deep neural networks (DNNs) and ubiquitous citizen science data. Based on 6.7 M observations, we jointly model the distributions of 2477 plant species and species aggregates across Switzerland with an ensemble of DNNs built with different cost functions. We find that, compared to commonly-used approaches, multispecies DNNs predict species distributions and especially community composition more accurately. Moreover, their design allows investigation of understudied aspects of ecology. Including seasonal variations of observation probability explicitly allows approximating flowering phenology; reweighting predictions to mirror cover-abundance allows mapping potentially canopy-dominant tree species nationwide; and projecting DNNs into the future allows assessing how distributions, phenology, and dominance may change. Given their skill and their versatility, multispecies DNNs can refine our understanding of the distribution of plants and well-sampled taxa in general. By modelling the distribution of the entire Swiss flora using deep learning and citizen science data, this study demonstrates a method that predicts flowering phenology and potentially dominant tree species more accurately than commonly used approaches. This approach could enable investigation of understudied aspects of ecology and refine our understanding of plant distributions. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Ceratonia siliqua L. (Carob) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the International Biological Flora: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation. Ceratonia siliqua is a lowland evergreen shrub or tree, native around the Mediterranean basin and widely cultivated in areas with a warm temperate and subtropical climate, with more than 100 named cultivars. Carob grows on a wide range of soils including nutrient‐poor and strongly calcareous, dry soils. Carob is dioecious or rarely hermaphrodite although females dominate in cultivation due to their fruit. Pollination is primarily by insects and the relatively large seeds are spread mainly by ingestion of fruits by mammals. Seed dormancy is imposed by a hard seed coat and seeds germinate readily after natural or artificial scarification. Drought tolerance is very high, acting as a drought avoiding water spender. Carob is also very tolerant of saline conditions and tolerant of fire and can act to restrict wildfire spread by generating fuel discontinuity. It shows high post‐fire regrowth. Old individuals house a diversity of associated fauna and are comparatively unaffected by serious pests and diseases. Carob has a long cultural history around the Mediterranean as a food source for humans and domesticated animals, in herbal and modern medicine and, more recently, for the carob bean gum used in a variety of domestic products and foods. Commercial production of fruits has declined over past decades but the low cultural care needed in growing orchards, potential new markets for fruit and seeds, and growing use of the tree to prevent soil erosion and sequester carbon gives carob a brighter future. [ABSTRACT FROM AUTHOR]

Air pollution caused by tropospheric ozone contributes to the decline of forest ecosystems; for instance, sacred fir, Abies religiosa (Kunth) Schltdl. & Cham. forests in the peri-urban region of Mexico City. Individual trees within these forests exhibit variation in their response to ozone exposure, including the severity of visible symptoms in needles. Using RNA-Seq metatranscriptomic data and ITS2 metabarcoding, we investigated whether symptom variation correlates with the taxonomic and functional composition of fungal mycobiomes from needles collected in this highly polluted area in the surroundings of Mexico City. Our findings indicate that ozone-related symptoms do not significantly correlate with changes in the taxonomic composition of fungal mycobiomes. However, genes coding for 30 putative proteins were differentially expressed in the mycobiome of asymptomatic needles, including eight genes previously associated with resistance to oxidative stress. These results suggest that fungal communities likely play a role in mitigating the oxidative burst caused by tropospheric ozone in sacred fir. Our study illustrates the feasibility of using RNA-Seq data, accessible from global sequence repositories, for the characterization of fungal communities associated with plant tissues, including their gene expression. [ABSTRACT FROM AUTHOR]

Summary: Phosphorus (P) for carbon (C) exchange is the pivotal function of arbuscular mycorrhiza (AM), but how this exchange varies with soil P availability and among co‐occurring plants in complex communities is still largely unknown.We collected intact plant communities in two regions differing c. 10‐fold in labile inorganic P. After a 2‐month glasshouse incubation, we measured 32P transfer from AM fungi (AMF) to shoots and 13C transfer from shoots to AMF using an AMF‐specific fatty acid. AMF communities were assessed using molecular methods.AMF delivered a larger proportion of total shoot P in communities from high‐P soils despite similar 13C allocation to AMF in roots and soil. Within communities, 13C concentration in AMF was consistently higher in grass than in blanketflower (Gaillardia aristata Pursh) roots, that is P appeared more costly for grasses. This coincided with differences in AMF taxa composition and a trend of more vesicles (storage structures) but fewer arbuscules (exchange structures) in grass roots. Additionally, 32P‐for‐13C exchange ratios increased with soil P for blanketflower but not grasses.Contrary to predictions, AMF transferred proportionally more P to plants in communities from high‐P soils. However, the 32P‐for‐13C exchange differed among co‐occurring plants, suggesting differential regulation of the AM symbiosis. [ABSTRACT FROM AUTHOR]

Summary: Quantifying the abundances of fungi is key to understanding natural variation in mycorrhizal communities in relation to plant ecophysiology and environmental heterogeneity. High‐throughput metabarcoding approaches have transformed our ability to characterize and compare complex mycorrhizal communities. However, it remains unclear how well metabarcoding read counts correlate with actual read abundances in the sample, potentially limiting their use as a proxy for species abundances.Here, we use droplet digital PCR (ddPCR) to evaluate the reliability of ITS2 metabarcoding data for quantitative assessments of mycorrhizal communities in the orchid species Neottia ovata sampled at multiple sites. We performed specific ddPCR assays for eight families of orchid mycorrhizal fungi and compared the results with read counts obtained from metabarcoding.Our results demonstrate a significant correlation between DNA copy numbers measured by ddPCR assays and metabarcoding read counts of major mycorrhizal partners of N. ovata, highlighting the usefulness of metabarcoding for quantifying the abundance of orchid mycorrhizal fungi. Yet, the levels of correlation between the two methods and the numbers of false zero values varied across fungal families, which warrants cautious evaluation of the reliability of low‐abundance families.This study underscores the potential of metabarcoding data for more quantitative analyses of mycorrhizal communities and presents practical workflows for metabarcoding and ddPCR to achieve a more comprehensive understanding of orchid mycorrhizal communities. [ABSTRACT FROM AUTHOR]

The study explores the impact of mine grassland restoration on plant communities and soil properties in alpine grasslands, a subject of significant interest due to the observed relationship between grassland changes, plant communities, and soil properties. While prior research has mainly focused on the consequences of grassland degradation on plant diversity and soil characteristics, the specific effects of varying restoration degrees in alpine mining grasslands at the regional scale remain poorly understood. To address this knowledge gap, we established 15 sampling plots (0.5m×0.5m) across five different restoration degrees within alpine mining grasslands in the Qilian Mountains, China. Our objective was to assess the variations in plant diversity and soil properties along these restoration gradients. We conducted comprehensive analyses, encompassing soil properties [soil water content (SWC), available nitrogen (AN), total phosphorus (TP), nitrate nitrogen (NO3-N), ammonium nitrogen (NH4-N), total nitrogen (TN), available phosphorus (AP), soil organic carbon (SOC), nitrate nitrogen, soil pH, and electrical conductivity (EC)], plant characteristics (height, density, frequency, coverage, and aboveground biomass), and plant diversity indices (Simpson, Shannon-Wiener, Margalef, Dominance, and Evenness indexes). Our findings included the identification and collection of 18 plant species from 11 families and 16 genera across the five restoration degrees: Very Low Restoration Degree (VLRD), Low Restoration Degree (LRD), Moderate Restoration Degree (MRD), High Restoration Degree (HRD), and Natural Grassland (NGL). Notably, species like Carex duriuscula, Cyperus rotundus, and Polygonum viviparum showed signs of recovery. Principal component analysis and Pearson correlation analysis revealed that soil pH, SWC, SOC, NO3-N, and AN were the primary environmental factors influencing plant communities. Specifically, soil pH and EC decreased as restoration levels increased, while SWC, AN, TP, NH4-N, TN, AP, SOC, and NO3-N exhibited a gradual increase with greater restoration efforts. Furthermore, the HRD plant community demonstrated similarities to the NGL, indicating the most effective natural recovery. In conclusion, our study provides valuable insights into the responses of plant community characteristics, plant diversity, and soil properties across varying restoration degrees to environmental factors. It also elucidates the characteristics of plant communities along recovery gradients in alpine grasslands. [ABSTRACT FROM AUTHOR]

Microbial communities associated with plants growing in harsh conditions, including salinity and water deficiency, have developed adaptive features which permit them to grow and survive under extreme environmental conditions. In the present study, an ex-situ plant trapping method has been applied to collect the culturable microbial diversity associated with the soil from harsh and remote areas. Oryza sativa cv. Baldo and Triticum durum Primadur plants were used as recruiters, while the soil surrounding the roots of Oryza glaberrima plants from remote regions of Mali (West Africa) was used as substrate for their growth. The endophytic communities recruited by the two plant species belonged to Proteobacteria and Firmicutes, and the dominant genera were Bacillus, Kosakonia , and Enterobacter. These endophytes were characterized by analyzing some of the most common plant growth promoting traits. Halotolerant, inorganic phosphate-solubilizing and N-fixing strains were found, and some of them simultaneously showing these three traits. We verified that 'Baldo' recruited mostly halotolerant and P-solubilizers endophytes, while the endophytes selected by 'Primadur' were mainly N-fixers. The applied ex-situ plant trapping method allowed to isolate endophytes with potential beneficial traits that could be applied for the improvement of rice and wheat growth under adverse environmental conditions. [ABSTRACT FROM AUTHOR]

Interactions between carbon (C), nitrogen (N), and phosphorus (P), the vital indicators of ecological restoration, play an important role in signaling the health of ecosystems. Rapidly and accurately mapping foliar C, N, and P is essential for interpreting community structure, nutrient limitation, and primary production during ecosystem recovery. However, research on how to rapidly map C, N, and P in restored areas with mixed plant communities is limited. This study employed laser imaging, detection, and ranging (LiDAR) and hyperspectral data to extract spectral, textural, and height features of vegetation as well as vegetation indices and structural parameters. Causal band, multiple linear regression, and random forest models were developed and tested in a restored area in northern China. Important parameters were identified including (1), for C, red-edge bands, canopy height, and vegetation structure; for N, textural features, height percentile of 40–95%, and vegetation structure; for P, spectral features, height percentile of 80%, and 1 m foliage height diversity. (2) R2 was used to compare the accuracy of the three models as follows: R2 values for C were 0.07, 0.42, and 0.56, for N they were 0.20, 0.48, and 0.53, and for P they were 0.32, 0.39, and 0.44; the random forest model demonstrated the highest accuracy. (3) The accuracy of the concentration estimates could be ranked as C > N > P. (4) The inclusion of LiDAR features significantly improved the accuracy of the C concentration estimation, with increases of 22.20% and 47.30% in the multiple linear regression and random forest models, respectively, although the inclusion of LiDAR features did not notably enhance the accuracy of the N and P concentration estimates. Therefore, LiDAR and hyperspectral data can be used to effectively map C, N, and P concentrations in a mixed plant community in a restored area, revealing their heterogeneity in terms of species and spatial distribution. Future efforts should involve the use of hyperspectral data with additional bands and a more detailed classification of plant communities. The application of this information will be useful for analyzing C, N, and P limitations, and for planning for the maintenance of restored plant communities. [ABSTRACT FROM AUTHOR]

We are entering an exciting century in the study of the plant organelles in the endomembrane system. Over the past century, especially within the past 50 years, tremendous advancements have been made in the complex plant cell to generate a much clearer and informative picture of plant organelles, including the molecular/morphological features, dynamic/spatial behavior, and physiological functions. Importantly, all these discoveries and achievements in the identification and characterization of organelles in the endomembrane system would not have been possible without: (1) the innovations and timely applications of various state-of-art cell biology tools and technologies for organelle biology research; (2) the continuous efforts in developing and characterizing new organelle markers by the plant biology community; and (3) the landmark studies on the identification and characterization of the elusive organelles. While molecular aspects and results for individual organelles have been extensively reviewed, the development of the techniques for organelle research in plant cell biology is less appreciated. As one of the ASPB Centennial Reviews on "organelle biology," here we aim to take a journey across a century of organelle biology research in plants by highlighting the important tools (or landmark technologies) and key scientists that contributed to visualize organelles. We then highlight the landmark studies leading to the identification and characterization of individual organelles in the plant endomembrane systems. The landmark tools and key studies leading to the identification and characterization of organelles in the plant endomembrane systems. [ABSTRACT FROM AUTHOR]

Environmental filtering and competition are two fundamental processes that shape plant community assembly in terms of functional composition, that is, the distribution of trait values. Understanding the role of these two processes in the assembly of non‐vascular vegetation, such as bryophytes and lichens, is important since these communities provide essential ecosystem services in many regions around the world, and these depend on functional composition. Responses of non‐vascular communities to environmental selection pressures have been explored in a range of experimental and modelling studies. However, it is still largely unknown to what extent competition affects the distribution of functional traits of non‐vascular communities. Moreover, it remains poorly explored which traits that are associated with competition are key for shaping community functional assembly.Here, we integrated a field transplantation experiment with a process‐based model to disentangle the effects of environmental filtering and competition on the assembly of non‐vascular communities. Following the validation of environmental selection in the model using field observations, we performed a simulation experiment to understand the impacts of competition on trait distributions in non‐vascular communities growing in two temperate locations that differ in microclimatic conditions (a shaded and an open location).Our results suggest that the functional composition is likely a result of weak competition or may not depend on competitive exclusion at all while environmental filtering plays an essential role. Plant height seems to be a key trait for competition. However, no single‐trait competition scheme could consistently explain the observed functional composition of the studied non‐vascular communities.Synthesis. The presented model provides a new trait‐based approach for simulating the functional assembly of non‐vascular communities. Environmental filtering appears to be more essential than competition for predicting trait distributions of non‐vascular communities under temperate climatic conditions and we recommend caution in associating competition to a single trait while analysing community functional assembly. [ABSTRACT FROM AUTHOR]

The wolf (Canis lupus) is arguably the most successful species at recolonizing its now human‐dominated former ranges in Europe and North America. Over the centuries while the wolf was absent, humans have transformed ecosystems to a large extent. In this paper, we highlight key aspects of these human‐modified ecosystems that include changes to (meso)carnivore communities, wolves themselves (genetics, behaviour), woody plant communities and the playing field for predator–prey interactions (landscape structure).We argue that the recognition of the novelty of human‐modified ecosystems logically leads to novel pathways of how wolves can influence ecosystem functioning. Thus far, the ecological impacts of wolves in human‐dominated systems have largely been predicted based on the documented effects they have on prey species or lower trophic levels in well‐preserved systems with low human impact. However, wolves in human‐modified ecosystems will engage in an array of novel interactions and potential novel trophic cascades that do not occur in more natural ecosystems with lower human impact.This should encourage us to re‐assess the questions we ask about wolf impacts in novel systems. A promising direction for future studies is exploring what novel interactions establish and under what conditions wolves can exert their ecosystem impacts (context dependence) in the human‐modified ecosystems wolves are recolonizing.Policy implications. Understanding these novel interactions and the context dependence of ecosystem impacts could guide us to act to improve conditions to enable wolves to exert their ecosystem impacts again. These novel interactions may be the true ecological and societal value of having wolves returning to human‐modified landscapes. [ABSTRACT FROM AUTHOR]

Restoration outcomes are variable, which impairs our ability to plan projects, meet goals, and predict restoration outcomes. Understanding the drivers of this variation is an important research need, especially within urban ecosystems, which support altered abiotic and biotic conditions and face higher rates of loss and degradation than non‐urban areas. Despite the importance of urban areas for restoration, research and practice have largely focused on non‐urban areas. It is unclear if we can extend current knowledge from restoration ecology to urban systems. Here, we surveyed 30 urban prairie restoration plantings across southern Michigan. We collected plant community and site condition data (e.g. soil attributes) and we quantified landscape context as the percentage of urban land surrounding each site. Variation in plant community composition among restorations was related primarily to site‐level factors, such as soil compaction, texture, and water‐holding capacity, rather than landscape context. Non‐prairie species were structured primarily by the local site conditions. There was an increase in non‐prairie richness for sites that experienced warmer local climate conditions, while there was a decrease in non‐prairie richness for sites where soils were less compacted, sandier, and had elevated water‐holding capacity. Prairie species richness responded oppositely. Overall, our study revealed specific factors structuring restoration outcomes in urban contexts and illustrated the importance of local site conditions, not surrounding landscape context, for shaping plant community composition. Restoration practices developed in non‐urban areas should be extended to urban contexts to better understand the impact of local site conditions on plant community development. [ABSTRACT FROM AUTHOR]

Reestablishment of native plant communities is often the primary focus of ecological restoration. This is especially true for prairie restoration, which often struggles to establish diverse forb communities. An often‐overlooked component in plant reestablishment is pollinators, with 85% of forbs requiring pollination for seed reproduction. A deeper understanding of the relationship between plant and pollinator communities could improve prairie restoration success. Our goal was to determine if prairie restoration is successfully reestablishing forb and pollinator communities and their interactions by measuring plant–pollinator networks. We hypothesized that both forb and pollinator communities would be less diverse and abundant in restoration sites compared to intact prairie remnants, and that as a result, plant–pollinator networks in restoration sites would have higher nestedness and connectance, but lower modularity and network specialization than remnant sites. To test this, we measured plant–pollinator networks and forb communities from June to September 2020 at three restored and three remnant Palouse Prairie sites in eastern Washington, United States. We found that although restored sites had lower species richness of forbs and pollinators and different community composition, forb and pollinator abundance was comparable between treatments. Forb abundance in restored sites was equivalent to prairie remnants due to the presence of invasive forbs. However, these differences in community composition and diversity did not appear to impact network metrics including nestedness, connectance, modularity, and network specialization, which were similar between remnant and restored sites. Our results suggest that the structural characteristics of plant–pollinator networks can be maintained by different plant communities. [ABSTRACT FROM AUTHOR]

Community stability plays a crucial role in ensuring the consistent provision of ecosystem services despite environmental changes, including alterations in precipitation patterns. Over the past decades, significant progress has been made in understanding the responses of the stability of grassland plant communities and underlying mechanisms, defined as the ratio of the temporal mean biomass to the standard deviation. However, a crucial knowledge gap remains regarding whether the impacts of precipitation on the stability of grassland biomass are contingent upon specific contextual factors.Here, we examined the stability of above‐ and below‐ground biomass in adjacent grass‐ and shrub‐dominated communities through a 7‐year manipulation experiment involving seven precipitation levels: 20%, 40% and 60% decrease, as well as 20%, 40% and 60% increase in natural rainfall, in addition to ambient precipitation.We found that the stability of community biomass was influenced by three contextual factors including the magnitude and directionality of precipitation, above‐ and below‐ground biomass and the type of vegetation. In particular, higher and more intense precipitation resulted in higher stability of above‐ground biomass in both grass‐ and shrub‐dominated communities. Conversely, higher precipitation intensity led to decreased below‐ground biomass stability in grass‐dominated communities but increased below‐ground biomass stability in shrub‐dominated communities. Species stability and species asynchrony consistently played a positive role in explaining the stability of above‐ground biomass in both grass‐ and shrub‐dominated communities. However, species asynchrony negatively influenced below‐ground biomass stability in grass‐dominated communities without a comparable effect in shrub‐dominated communities. The preeminent contribution to the total community biomass was identified in the stability of below‐ground biomass, evident in both grass‐dominated and shrub‐dominated communities.Synthesis. This study highlights that while the specific effects of changes in precipitation may vary depending on the context, the fundamental processes governing biomass stability are consistent. These findings elucidate the desert steppe ecosystems' adaptive response to precipitation variations and emphasize their pivotal role in maintaining ecosystem functions under climatic perturbations. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Pathogens are ubiquitous in ecosystems and play a key role in affecting host community structure. In grasslands, large grazing animals such as cattle and sheep have been shown to affect foliar fungal pathogens. However, theory and empirical studies have come to conflicting conclusions because grazers can directly and indirectly impact pathogens through a wide variety of mechanisms and various grazers may impact pathogens in different ways. A better understanding of the mechanisms by which grazers impact pathogens is important for a fundamental understanding of herbivore pathogen interactions and also to optimise grazing managements to reduce pathogen outbreaks.Here, we investigate multiple mechanisms by which livestock grazing impacts foliar fungal pathogens in grasslands. We integrate a large‐scale grazing experiment, with a removal experiment manipulating plant density and litter biomass, to identify direct and indirect effects of two herbivores on pathogens with different life histories (biotrophs and necrotrophs), in a temperate grassland in northeast China.We found that grazing by cattle and sheep had contrasting impacts: cattle grazing significantly reduced pathogen load, of both biotrophs and necrotrophs, whereas sheep grazing increased biotrophic pathogen load, but did not affect the necrotrophs. The grazing effects were mostly indirect and mediated by different impacts of the herbivores on plant community structure. Cattle grazing reduced pathogen load because it reduced the abundance of susceptible, fast‐growing plants, and the overall density of plants, while sheep grazing increased pathogen infection because it reduced the abundance of resistant plant species. Plant diversity also reduced pathogen infection but these effects were independent of the herbivores.Our results show that different herbivores can have contrasting impacts on pathogen infection through contrasting impacts on host community competence. This suggests the importance of considering multiple mechanisms simultaneously to evaluate the impact of herbivores on host‐pathogen interactions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Plants face trade‐offs between allocating resources to growth, while also defending against herbivores or pathogens. Species differences along defense trade‐off axes may promote coexistence and maintain diversity. However, few studies of plant communities have simultaneously compared defense trade‐offs against an array of herbivores and pathogens for which defense investment may differ, and even fewer have been conducted in the complex natural communities in which these interactions unfold. We tested predictions about the role of defense trade‐offs with competition and growth in diversity maintenance by tracking plant species abundance in a field experiment that removed individual consumer groups (mammals, arthropods, fungi) and added nutrients. Consistent with a growth–defense trade‐off, plant species that increased in mass in response to nutrient addition also increased when consumers were removed. This growth–defense trade‐off occurred for all consumer groups studied. Nutrient addition reduced plant species richness, which is consistent with trade‐off theory. Removing foliar fungi increased plant diversity via increased species evenness, whereas removal of other consumer groups had little effect on diversity, counter to expectations. Thus, while growth–defense trade‐offs are general across consumer groups, this trade‐off observed in wild plant communities does not necessarily support plant diversity maintenance. [ABSTRACT FROM AUTHOR]

Biodiversity can stabilize ecological communities through biological insurance, but climate and other environmental changes may disrupt this process via simultaneous ecosystem destabilization and biodiversity loss. While changes to diversity–stability relationships (DSRs) and the underlying mechanisms have been extensively explored in terrestrial plant communities, this topic remains largely unexplored in benthic marine ecosystems that comprise diverse assemblages of producers and consumers. By analyzing two decades of kelp forest biodiversity survey data, we discovered changes in diversity, stability, and their relationships at multiple scales (biological organizational levels, spatial scales, and functional groups) that were linked with the most severe marine heatwave ever documented in the North Pacific Ocean. Moreover, changes in the strength of DSRs during/after the heatwave were more apparent among functional groups than both biological organizational levels (population vs. ecosystem levels) and spatial scales (local vs. broad scales). Specifically, the strength of DSRs decreased for fishes, increased for mobile invertebrates and understory algae, and were unchanged for sessile invertebrates during/after the heatwave. Our findings suggest that biodiversity plays a key role in stabilizing marine ecosystems, but the resilience of DSRs to adverse climate impacts primarily depends on the functional identities of ecological communities. [ABSTRACT FROM AUTHOR]

In northern British Columbia and southern Yukon woodland, caribou forage extensively on terrestrial lichens, predominately mat-forming Cladina species in late-successional pine-lichen woodlands. Many of these stands are now reaching a point in their development where lichen abundance declines as feather-moss mats increase. We evaluated the response of forest floor plant communities in pine-lichen woodlands from the southern Yukon Lewes Marsh partial-cutting trial 8 years after harvesting. Photoplot results documented a major decline (>60% ± 5.6% SE) in the mean surface area of existing large clumps of C. mitis in control (unharvested) treatments, whereas the mean surface area of large C. mitis clumps declined by 28% (±15% SE) in the one-third basal-area removal and showed an increase of 13.5% (±25% SE) in the two-thirds basal-area removal. Line intercept transects documented no changes in overall stand-level lichen abundance between pre-harvest (2012) and post-harvest (2021) measurements, while feather-moss mats and dwarf shrubs showed declines and increases, respectively, in partial-cutting harvest plots. Stand thinning may provide a bridging strategy to extend the period of forage lichen availability in late-seral pine-lichen woodlands, an important consideration in landscapes where increasing severity and frequency of fires are changing the seral-state distribution of caribou habitat. [ABSTRACT FROM AUTHOR]

The relationship between biodiversity and ecosystem functioning strengthens with ecosystem age. However, the interplay between the plant diversity - ecosystem functioning relationship and Glomeromycotinian arbuscular mycorrhizal fungi (AMF) community assembly has not yet been scrutinized in this context, despite AMF's role in plant survival and niche exploration. We study the development of AMF communities by disentangling soil- and plant-driven effects from calendar year effects. Within a long-term grassland biodiversity experiment, the pre-existing plant communities of varying plant diversity were re-established as split plots with combinations of common plant and soil histories: split plots with neither common plant nor soil history, with only soil but no plant history, and with both common plant and soil history. We found that bulk soil AMF communities were primarily shaped by common soil history, and additional common plant history had little effect. Further, the steepness of AMF diversity and plant diversity relationship did not strengthen over time, but AMF community evenness increased with common history. Specialisation of AMF towards plant species was low throughout, giving no indication of AMF communities specialising or diversifying over time. The potential of bulk soil AMF as mediators of variation in plant and microbial biomass over time and hence as drivers of biodiversity and ecosystem relationships was low. Our results suggest that soil processes may be key for the build-up of plant community-specific mycorrhizal communities with likely feedback effects on ecosystem productivity, but the plant-available mycorrhizal pool in bulk soil itself does not explain the strengthening of biodiversity and ecosystem relationships over time. [ABSTRACT FROM AUTHOR]

Working pine (Pinus spp.) forests in the southern United States rely on herbicides to remove competing vegetation and improve productivity. We conducted a review of the effects of herbicides on understory plants in southern working forests. We also discuss the impacts of herbicides on insect taxa associated with understory vegetation and its litter layer, including Coleoptera (carabid beetles), Hemiptera (true bugs), Hymenoptera (bees/ants), Lepidoptera (moths/butterflies), and Orthoptera (grasshoppers). Herbicides have few reported long-term impacts on understory herbaceous cover and species richness/diversity when applied according to labeled uses and application rates. However, the method of chemical treatment (e.g. broadcast spray or banded application) may influence understory plant structure and composition. Responses of insects to herbicides were species- and taxa-specific and highly variable given their forage/habitat requirements and life histories. Long-term research is needed to evaluate the effects of herbicides on vegetation-associated insects to provide a comprehensive profile of herbicide nontarget impacts. Study Implications: Land managers rely on herbicides to remove competing vegetation and increase working forest productivity. Given the objective of sustainable forest management to conserve biodiversity, it is important to understand how biological communities respond to chemical applications in intensively managed forest ecosystems. Our review indicated that herbicides have few reported long-term impacts on understory plant communities when applied appropriately. Despite their taxonomic diversity, invertebrates were rarely included in assessments of forest herbicides. Further research is needed to assess the potential nontarget impacts of herbicide applications on forest insect communities. [ABSTRACT FROM AUTHOR]

Dams cause loss of habitat due to the interception of sediment transport downstream. The impact of the Wadi Ma'awil watershed dam in Oman on the distribution and pattern of plant communities has not been fully investigated. Identifying and prioritizing critical erosion and trapped sediment areas are important aspects for policymakers. The aim of this study was to assess the impact of the Wadi Ma'awil watershed dam on sediment transport across the watershed and its consequences on the pattern and distribution of plant communities. This study used the integrated valuation of environmental services and the tradeoffs sediment delivery ratio (InVEST-SDR) model to provide spatially explicit estimates of soil loss and sediment yield. The results showed that Sub-watershed 10 after the dam area exhibited the lowest sediment export, with a value of 0.36 ton/ha, while Sub-watershed 2 at the dam area had sediment retention of 1.02 ton/ha among the top five sub-watersheds. Around 1.51 ton/ha of sediments was trapped inside the dam at Sub-watershed 2 and did not reach the downstream area at Sub-watershed 10. The dam had a significant effect on the distribution, density, and communities of the small plant. The area downstream of the dam Sub-watershed 10 showed the lowest mean plant density (3.15) compared to the area upstream of the dam Sub-watershed s 3, 4, and 5 (19.65) or the dam area Sub-watershed 2 (42.9). These findings suggest a need to evaluate dam capacity, as sediment traps could hold risks that could decrease dam functionality and life span, jeopardizing dam storage and flood protection capacity. [ABSTRACT FROM AUTHOR]

Microorganisms are crucial elements of terrestrial ecosystems, which play significant roles in improving soil physicochemical properties, providing plant growth nutrients, degrading toxic and harmful chemicals, and biogeochemical cycling. Variations in the types and quantities of root exudates among different plants greatly alter soil physicochemical properties and result in variations in the diversity, structure, and function of soil microorganisms. Not much is understood about the differences of soil fungi and archaea communities for different plant communities in coastal wetlands, and their response mechanisms to environmental changes. In this study, fungal and archaea communities in soils of Suaeda salsa, Phragmites australis, and Spartina alterniflora in the intertidal habitat of coastal wetlands were selected for research. Soil fungi and archaea were analyzed for diversity, community structure, and function using high throughput ITS and 16S rRNA gene sequencing. The study revealed significant differences in fungi and archaea’s diversity and community structure in the rhizosphere soil of three plant communities. At the same time, there is no significant difference in the functional groups. SOM, TP, AP, MC, EC and SOM, TN, TP, AP, MC, EC are the primary environmental determinants affecting changes in soil fungal and archaeal communities, respectively. Variations in the diversity, community structure, and ecological functions of fungi and archaea can be used as indicators characterizing the impact of external disturbances on the soil environment, providing a theoretical foundation for the effective utilization of soil microbial resources, thereby achieving the goal of environmental protection and health promotion. [ABSTRACT FROM AUTHOR]

Introduction: Tropical forests are characterized by intricate mosaics of speciesrich and structurally complex forest communities. Evaluating the functional vulnerability of distinct community patches is of significant importance in establishing conservation priorities within tropical forests. However, previous assessments of functional vulnerability in tropical forests have often focused solely on isolated factors or individual disturbance events, with limited consideration for a broad spectrum of disturbances and the responses of diverse species. Methods: We assessed the functional vulnerability of woody plant communities in a 60-ha dynamic plot within a tropical montane rainforest by conducting in silico simulations of a wide range disturbances. These simulations combined plant functional traits and community properties, including the distribution of functional redundancy across the entire trait space, the distribution of abundance across species, and the relationship between species trait distinctiveness and species abundance. We also investigated the spatial distribution patterns of functional vulnerability and their scale effects, and employed a spatial autoregressive model to examine the relationships between both biotic and abiotic factors and functional vulnerability at different scales. Results: The functional vulnerability of tropical montane rainforest woody plant communities was generally high (the functional vulnerability of observed communities was very close to that of the most vulnerable virtual community, with a value of 72.41% on average at the 20m×20m quadrat scale), and they exhibited significant spatial heterogeneity. Functional vulnerability decreased with increasing spatial scale and the influence of both biotic and abiotic factors on functional vulnerability was regulated by spatial scale, with soil properties playing a dominant role. Discussion: Our study provides new specific insights into the comprehensive assessment of functional vulnerability in the tropical rainforest. We highlighted that functional vulnerabilities of woody plant communities and their sensitivity to environmental factors varied significantly within and across spatial scales in the tropical rainforest landscape. Preserving and maintaining the functionality of tropical ecosystems should take into consideration the variations in functional vulnerability among different plant communities and their sensitivity to environmental factors. [ABSTRACT FROM AUTHOR]

Introduction: Sorghum plant color is the leaf sheath/leaf color and is associated with seed color, tannin and phenol content, head blight disease incidence, and phytoalexin production. Results: In this study, we evaluated plant color of the sorghum mini core collection by scoring leaf sheath/leaf color at maturity as tan, red, or purple across three testing environments and performed genome-wide association mapping (GWAS) with 6,094,317 SNPs markers. Results and Discussion: Eight loci, one each on chromosomes 1, 2, 4, and 6 and two on chromosomes 5 and 9, were mapped. All loci contained one to three candidate genes. In qPC5-1, Sobic.005G165632 and Sobic.005G165700 were located in the same linkage disequilibrium (LD) block. In qPC6, Sobic.006G149650 and Sobic.006G149700 were located in the different LD block. The single peak in qPC6 covered one gene, Sobic.006G149700, which was a senescence regulator. We found a loose correlation between the degree of linkage and tissue/organ expression of the underlying genes possibly related to the plant color phenotype. Allele analysis indicated that none of the linked SNPs can differentiate between red and purple accessions whereas all linked SNPs can differentiate tan from red/purple accessions. The candidate genes and SNP markers may facilitate the elucidation of plant color development as well as molecular plant breeding. [ABSTRACT FROM AUTHOR]

Growing crops in more diverse crop systems (i.e., intercropping) is one way to produce food more sustainably. Even though intercropping, compared to average monocultures, is generally more productive, the full yield potential of intercropping might not yet have been achieved as modern crop cultivars are bred to be grown in monoculture. Breeding plants for more familiarity in mixtures, i.e., plants that are adapted to more diverse communities (i.e., adaptation) or even to coexist with each other (i.e., coadaptation) might have the potential to sustainably enhance productivity. In this study, the productivity benefits of familiarity through evolutionary adaptation and coevolutionary coadaptation were disentangled in a crop system through an extensive common garden experiment. Furthermore, evolutionary and coevolutionary effects on species-level and community-level productivity were linked to corresponding changes in functional traits. We found evidence for higher productivity and trait convergence with increasing familiarity with the plant communities. Furthermore, our results provide evidence for the coevolution of plants in mixtures leading to higher productivity of coadapted species. However, with the functional traits measured in our study, we could not fully explain the productivity benefits found upon coevolution. Our study investigated coevolution among randomly interacting plants and was able to demonstrate that coadaptation through coevolution of coexisting species in mixtures occurs and promotes ecosystem functioning (i.e., higher productivity). This result is particularly relevant for the diversification of agricultural and forest ecosystems, demonstrating the added value of artificially selecting plants for the communities they are familiar with. [ABSTRACT FROM AUTHOR]

Background: Luffa (Luffa spp.) is an economically important crop of the Cucurbitaceae family, commonly known as sponge gourd or vegetable gourd. It is an annual cross-pollinated crop primarily found in the subtropical and tropical regions of Asia, Australia, Africa, and the Americas. Luffa serves not only as a vegetable but also exhibits medicinal properties, including anti-inflammatory, antidiabetic, and anticancer effects. Moreover, the fiber derived from luffa finds extensive applications in various fields such as biotechnology and construction. However, luffa Fusarium wilt poses a severe threat to its production, and existing control methods have proven ineffective in terms of cost-effectiveness and environmental considerations. Therefore, there is an urgent need to develop luffa varieties resistant to Fusarium wilt. Single-plant GWAS (sp-GWAS) has been demonstrated as a promising tool for the rapid and efficient identification of quantitative trait loci (QTLs) associated with target traits, as well as closely linked molecular markers. Results: In this study, a collection of 97 individuals from 73 luffa accessions including two major luffa species underwent single-plant GWAS to investigate luffa Fusarium wilt resistance. Utilizing the double digest restriction site associated DNA (ddRAD) method, a total of 8,919 high-quality single nucleotide polymorphisms (SNPs) were identified. The analysis revealed the potential for Fusarium wilt resistance in accessions from both luffa species. There are 6 QTLs identified from 3 traits, including the area under the disease progress curve (AUDPC), a putative disease-resistant QTL, was identified on the second chromosome of luffa. Within the region of linkage disequilibrium, a candidate gene homologous to LOC111009722, which encodes peroxidase 40 and is associated with disease resistance in Cucumis melo, was identified. Furthermore, to validate the applicability of the marker associated with resistance from sp-GWAS, an additional set of 21 individual luffa plants were tested, exhibiting 93.75% accuracy in detecting susceptible of luffa species L. aegyptiaca Mill. Conclusion: In summary, these findings give a hint of genome position that may contribute to luffa wild resistance to Fusarium and can be utilized in the future luffa wilt resistant breeding programs aimed at developing wilt-resistant varieties by using the susceptible-linked SNP marker. [ABSTRACT FROM AUTHOR]

Carbon (C), nitrogen (N), and phosphorus (P) stoichiometry serve as valuable indices for plant nutrient utilization and biogeochemical cycling within ecosystems. However, the allocation of these nutrients among different plant organs and the underlying drivers in dynamic riparian ecosystems remain inadequately understood. In this study, we gathered plant samples from diverse life forms (annuals and perennials) and organs (leaves, stems, and roots) in the riparian zone of the Three Gorges Reservoir Region (TGRR) in China--a novel ecosystem subject to winter flooding. We used random forest analysis and structural equation modeling to find out how flooding, life forms, plant communities, and soil variables affect organs C, N, and P levels. Results showed that the mean concentrations of plant C, N, and P in the riparian zone of the TGRR were 386.65, 19.31, and 5.27 mg/g for leaves respectively, 404.02, 11.23, and 4.81 mg/g for stems respectively, and 388.22, 9.32, and 3.27 mg/g for roots respectively. The C:N, C:P and N:P ratios were 16.15, 191.7 and 5.56 for leaves respectively; 26.98, 273.72 and 4.6 for stems respectively; and 16.63, 223.06 and 4.77 for roots respectively. Riparian plants exhibited nitrogen limitation, with weak carbon sequestration, low nutrient utilization efficiency, and a high capacity for nutrient uptake. Plant C:N:P stoichiometry was significantly different across life forms and organs, with higher N and P concentrations in leaves than stems and roots, and higher in annuals than perennials. While flooding stress triggered distinct responses in the C, N, and P concentrations among annual and perennial plants, they maintained similar stoichiometric ratios along flooding gradients. Furthermore, our investigation identified soil properties and life forms as more influential factors than plant communities in shaping variations in C:N:P stoichiometry in organs. Flooding indirectly impacts plant C:N:P stoichiometry primarily through alterations in plant community composition and soil factors. This study underscores the potential for hydrologic changes to influence plant community composition and soil nutrient dynamics, and further alter plant ecological strategies and biogeochemical cycling in riparian ecosystems. [ABSTRACT FROM AUTHOR]

Previous research has indicated that natural landscapes exhibit a greater capacity for ameliorating negative emotional states in individuals when compared to urban landscapes. Nevertheless, significant scientific inquiries, such as the uniformity of the rejuvenating effect across distinct categories of natural landscapes on college students and the choice of the optimal plant community for achieving the most potent restorative effect, remain unexplored. This study aimed to address these questions by selecting four plant communities (singlelayer grassland, single-layer woodland, tree-grass composite woodland, treeshrub- grass composite woodland) and using an electroencephalography method to capture the neuroelectric activity of the participants in combination with the Positive and Negative Affect Schedule score to explore the effects of plant community types on emotional recovery. The results showed that all four plant communities significantly increased positive emotions and significantly reduced negative emotions. There was no significant difference in the recovery effect of positive emotions among the four plant community types, but there was a significant difference in the recovery effect of negative emotions. The effect of tree-shrub-grass composite woodland on the negative emotion recovery effect is the best; the EEG results found that the alpha wave amplitude induced by the tree-shrub-grass composite woodland was significantly higher than that of the other three groups of plant communities, and the EEG and behavioral results were consistent. The results show that the tree-shrub-grass composite woodland has the best restoration effect and has stronger planning and design significance. [ABSTRACT FROM AUTHOR]

Long‐term studies are needed to monitor recovery following restoration, as it may take decades or even centuries, particularly in the case of Mediterranean dry grasslands, for communities to reach their former equilibrium before the degradation occurred. A multi‐component approach is also needed to evaluate restoration success and better understand the complex impacts of former restoration projects on present‐day ecological interactions and ecosystem functions. The objective of this study was to address the restoration of a Mediterranean grassland in southern France, 20 years after implementation. Particularly, we examine the long‐term impact on soil, vegetation, and arthropods of the reintroduction of a dominant grass species (Brachypodium retusum) and the restoration of the natural stone cover on a degraded former cultivated field. Soil analyses revealed that reestablishing stone cover only slightly acidified the soil, while B. retusum presence enhanced soil fertility. Brachypodium retusum also decreased the nutritional value of forage and increased plant biomass and litter. Plant composition shifted with treatments: B. retusum and stone cover favored xeromesophilous species, while B. retusum alone encouraged less palatable species. The soil seed bank composition and abundance were positively influenced by stone cover but negatively impacted by B. retusum reintroduction. Negative outcomes on some arthropods and mesofauna were measured in treatments with both B. retusum and stones, except for Acari, which were positively impacted by the presence of stones. The findings emphasize that B. retusum is an ecological engineer with complex effects on the different ecosystem components. [ABSTRACT FROM AUTHOR]

Climate change is significantly affecting mountain plant communities, causing dynamic alterations in species composition as well as spatial distribution. This raises the need for constant monitoring. The Tatra Mountains are the highest range of the Carpathians which are considered biodiversity hotspots in Central Europe. For this purpose, microwave Sentinel-1 and optical multi-temporal Sentinel-2 data, topographic derivatives, and iterative machine learning methods incorporating classifiers random forest (RF), support vector machines (SVMs), and XGBoost (XGB) were used for the identification of thirteen non-forest plant communities (various types of alpine grasslands, shrublands, herbaceous heaths, mountain hay meadows, rocks, and scree communities). Different scenarios were tested to identify the most important variables, retrieval periods, and spectral bands. The overall accuracy results for the individual algorithms reached RF (0.83–0.96), SVM (0.87–0.93), and lower results for XGBoost (0.69–0.82). The best combination, which included a fusion of Sentinel-1, Sentinel-2, and topographic data, achieved F1-scores for classes in the range of 0.73–0.97 (RF) and 0.66–0.95 (SVM). The inclusion of topographic variables resulted in an improvement in F1-scores for Sentinel-2 data by one–four percent points and Sentinel-1 data by 1%–9%. For spectral bands, the Sentinel-2 10 m resolution bands B4, B3, and B2 showed the highest mean decrease accuracy. The final result is the first comprehensive map of non-forest vegetation for the Tatra Mountains area. [ABSTRACT FROM AUTHOR]

Summary: Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon‐rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics that represent important functional processes in tropical forests. We focus on: (1) fine‐root strategies for soil resource exploration, (2) coupling and trade‐offs in fine‐root water vs nutrient acquisition, and (3) aboveground–belowground linkages in plant resource acquisition and use. We suggest avenues for representing these extremely diverse plant communities in computationally manageable and ecologically meaningful groups in models for linked aboveground–belowground hydro‐nutrient functions. Tropical forests are undergoing warming, shifting rainfall regimes, and exacerbation of soil nutrient scarcity caused by elevated atmospheric CO2. The accurate model representation of tropical forest functions is crucial for understanding the interactions of this biome with the climate. [ABSTRACT FROM AUTHOR]

Although it is well known that groundwater significantly influences the plant communities, there have been few studies on how the soil and plant communities respond to a rapid decline of groundwater in a short time affected by coal mining. This paper focuses on the examination of changes in groundwater depth before and after coal mining and the soil‐vegetation response in a typical semi‐arid grassland coal mine area of Hulunbuir Steppe, Northeastern China. The IsoSource model, based on the dual stable isotopes of δ D and δ18O, was employed to estimate groundwater contributions to shallow soil (0–100 cm) water under different groundwater depths. The results revealed that groundwater was the dominant water source (75.7% ± 17.1%) for shallow soil water when the groundwater depth is less than 4 m, indicating that 4 m is a threshold in groundwater depth, separating groundwater‐dependent, and precipitation‐driven vegetation system in the study area. Secondly, a strong nonlinear response was observed between vegetation species, height, coverage, and the decline in groundwater. The vegetation properties were found to be the lowest in the areas where groundwater depth increased from 1.5–4 m to 4–28 m before and after coal mining. Finally, the groundwater level decline in the mining area significantly influenced the groundwater‐dependent vegetation ecosystem, the soil cation exchange capacity and organic matter reduced lead to the degradation of plant communities and the transition of mesophytes to xerophytes. Besides, the soil‐vegetation system in the non‐groundwater‐dependent area has no obvious response to the groundwater decline. These results suggest that caution should be exercised when mining in groundwater‐dependent ecosystem regions. [ABSTRACT FROM AUTHOR]

Due to its fortuitous mix of geography, terrain, and geology, Ethiopia is the home of unique assemblages of rich biodiversity. However, this impressive biological diversity is increasingly threatened by the combined effects of different drivers before they are sufficiently investigated. The present work was carried out in Robe-Raya Natural Forest, located in Southeast Ethiopia, with the intention of examining plant community formation and structural dynamics of the forest species. Sixty (20 m × 20 m) quadrats were placed at 100 m distance along eleven east-west directed transect lines systematically. In order to gather juvenile's data, five subquadrats (2 m × 2 m) were established within the main quadrat, distributed at each corner and middle. In each quadrat, all woody species were recorded and counted; diameter (DBH) and height were measured using tape meter and a hypsometer, respectively, and cover abundance was recorded (in %). Cluster analysis was computed using R-Package to map-out the community types. Species diversity and composition among community types were computed using the Shannon-Wiener index and Sorenson's coefficient, respectively. Frequency, density, height, DBH, basal area, and IVI were used to analyze structural dynamics. Age-class density ratios were used to examine the regeneration status. Ninety-four woody plant species belonging to 39 families were documented. Asteraceae was the most species-rich family (10 species). The common growth form was shrubs (44.7%) followed by trees (41.5%). Cluster analysis produced four community types. In total, the species diversity and evenness were 3.75 and 0.88, respectively. The forest density and basal area were 1183.3 stems/ha and 57.52 m2·ha−1, respectively. Structural dynamics analyses demonstrated that the forest was composed of, largely, young trees and shrubs and under fair regeneration status. Certain species that have been identified to have low IVI and poor regeneration status should be prioritized for conservation. [ABSTRACT FROM AUTHOR]

Introduction: Climate change has increased the need for forest restoration, but low planting success and limited availability of planting materials hamper these efforts. Invasive plants and their soil legacies can further reduce restoration success. Thus, strategies that optimize restoration are crucial. Assisted migration and inoculation with native microbial symbiont communities have great potential to increase restoration success. However, assisted migrants can still show reduced survival compared to local provenances depending on transfer distance. Inoculation with mycorrhizal fungi, effective if well-matched to plants and site conditions, can have neutral to negative results with poor pairings. Few studies have examined the interaction between these two strategies in realistic field environments where native plants experience the combined effects of soil legacies left by invasive plants and the drought conditions that result from a warming, drying climate. Methods: We planted two ecotypes (local climate and warmer climate) of Populus fremontii (Fremont cottonwoods), in soils with and without legacies of invasion by Tamarix spp. (tamarisk), and with and without addition of native mycorrhizal fungi and other soil biota from the warmer climate. Results: Four main results emerged. 1) First year survival in soil legacies left behind after tamarisk invasion and removal was less than one tenth of survival in soil without a tamarisk legacy. 2) Actively restoring soil communities after tamarisk removal tripled first year cottonwood survival for both ecotypes, but only improved survival of the warmer, assisted migrant ecotype trees in year two. 3) Actively restoring soil communities in areas without a tamarisk history reduced first year survival for both ecotypes, but improved survival of the warmer, assisted migrant ecotype trees in year two. 4) By the second year, inoculated assisted migrants survived at five times the rate of inoculated trees from the local ecotype. Discussion: Results emphasize the detrimental effects of soil legacies left after tamarisk invasion and removal, the efficacy of assisted migration and restoring soil communities alongside plants, and the need to thoughtfully optimize pairings between plants, fungi, and site conditions. [ABSTRACT FROM AUTHOR]

Wetland vegetation and ecology of Lake Abaya in the southern Ethiopia was studied to determine floristic composition, plant community type and vegetation ecology. A total of 102 plots were laid along transects that were set up preferentially across areas where there were rapid changes in vegetation or marked environmental gradients to collect data on estimate of percentage aerial cover of plant species and environmental variables. Vegetation data was analyzed by agglomerative hierarchical cluster analysis using similarity ratio as a resemblance index and Ward's linkage method. Multivariate data analysis was performed using appropriate packages in R version 2.14.0. Canonical Correspondence Analysis (CCA) was used to explore the relationship between the species composition and environmental variables. The environmental data included in the CCA were determined using stepwise backward and forward selection of variables by ANOVA test. Statistical measurement regarding species diversity, richness and evenness of the plant community types was carried out by using Shannon-Wiener diversity indices. A total of 92 plant species belonging to 66 genera and 34 families were identified. Families Poaceae, Asteraceae, Fabaceae, Cyperaceae, Solanaceae, Euphorbiaceae and Amaranthaceae account for about 56.99% of the total proportion. Based on the cluster analysis, five plant community types were identified. The most important factors influencing the plant species composition and pattern of wetland plant communities were water drainage, water depth, land use, slope, altitude, and hydrogeomorphology. Therefore, these factors should be considered in future management and protection under the circumstance of climate change and human activities. [ABSTRACT FROM AUTHOR]

Alpine wetland degradation threatens riparian biodiversity and ecological balance. Our study, conducted in July 2020 along the northern and eastern shores of Qinghai Lake, seeks to unravel the impacts of such degradation on plant species dominance and ecological niches, using advanced network analysis methods to explore the dynamics and survival strategies of plant species. We applied a space-to-time method to delineate three wetland degradation stage: a healthy swamp wetland, a slightly degraded wet meadow, and a degraded dry meadow. Six representative sampling points were chosen. At each point, three sample lines were randomly established, radiating outward from the center of the lake wetland, with each stage of degradation meticulously examined through three replicates to assess the plant communities in terms of species composition, plant height, coverage, and abundance. The results indicated: Species such as Kobresia tibetica and Leymus secalinus exhibit remarkable abundance across various stages of wetland degradation, indicating a robust tolerance to these conditions. This observation, coupled with the complexity of plant community structures in degrading wetlands, suggests that such intricacy cannot be solely attributed to the dominance of particular species. Instead, it is the result of a diverse array of species adapting to fluctuating water levels, which promotes increased species richness. Despite the prominence of species that exhibit rapid growth and reproduction, the ecological significance of less abundant species in contributing to the community's complexity is also notable. Changes in habitat conditions due to wetland degradation facilitate both competitive and cooperative interactions among species, highlighting the dynamic nature of these ecosystems. Our analysis shows no significant linear relationship between the ecological niche overlap values and niche widths of plant species. However, the strategies employed by dominant species for competition and resource acquisition, as observed in the ecological niche overlap networks, underscore the adaptive capacity of plant communities. These insights underscore the need for tailored restoration strategies to conserve the biodiversity of alpine lake riparian ecosystems. This research not only sheds light on the resilience and adaptability of ecosystems in the Qinghai-Tibetan Plateau but also offers valuable lessons for the conservation of similar habitats worldwide. Our findings underscore the need for tailored restoration strategies to conserve the biodiversity of alpine lake riparian ecosystems. This research not only sheds light on the resilience and adaptability of ecosystems in the Qinghai-Tibetan Plateau but also offers valuable lessons for the conservation of similar habitats worldwide. [ABSTRACT FROM AUTHOR]

Introduction: The components of nighttime sap flux (En), which include transpiration (Qn) and stem water recharge (Rn), play important roles in water balance and drought adaptation in plant communities in water-limited regions. However, the quantitative and controlling factors of En components are unclear. Methods: This study used the heat balance method to measure sap flow density in Vitex negundo on the Loess Plateau for a normal precipitation year (2021) and a wetter year (2022). Results: The results showed that the mean values were 1.04 and 2.34 g h-1 cm-2 for Qn, 0.19 and 0.45 g h-1 cm-2 for Rn in 2021 and 2022, respectively, and both variables were greater in the wetter year. The mean contributions of Qn to En were 79.76% and 83.91% in 2021 and 2022, respectively, indicating that the En was mostly used for Qn. Although the vapor pressure deficit (VPD), air temperature (Ta) and soil water content (SWC) were significantly correlated with Qn and Rn on an hourly time scale, they explained a small fraction of the variance in Qn on a daily time scale. The main driving factor was SWC between 40-200 cm on a monthly time scale for the Qn and Rn variations. Rn was little affected by meteorological and SWC factors on a daily scale. During the diurnal course, Qn and Rn initially both declined after sundown because of decreasing VPD and Ta, and Qn was significantly greater than Rn, whereas the two variables increased when VPD was nearly zero and Ta decreased, and Rn was greater than Qn. Discussion: These results provided a new understanding of ecophysiological responses and adaptation of V. negundo plantations to increasing drought severity and duration under climate changes. [ABSTRACT FROM AUTHOR]

A new disease syndrome of zucchini squash was observed in Southern Italy, in 2018 and again in 2020. Affected plants were severely stunted and leaves were bent downwards, small, stiff, thick, leathery, and had interveinal chloroses. In addition, flowers were virescent and fruits were deformed and often cracked. Disease incidence was 20 and 30% in two different zucchini cultivations in Campania region (Southern Italy). Tomato yellow leaf curl New Delhi virus (ToLCNDV) was detected in eight samples, by loop-mediated isothermal amplification-based (LAMP) kit and by PCR and Sanger sequencing of the AV1 gene. Phytoplasmas were detected in the same samples using nested PCR assays with primer pairs P1/P7 and R16F2n/R16R2. Phytoplasma associations in plant samples were confirmed using specific primers for the multilocus genes SecY, tuf and rp. Sequence comparison of multilocus genes and phylogenetic analyses of the 16S rDNA gene confirmed the association of a phytoplasma strain closely related to 'Candidiatus Phytoplamsa asteris'. This is the first report of mixed infections of ToLCNDV and a putative 'Ca. Phytoplamsa asteris' strain in zucchini, associated with a new Squash-Phytoplasma-Begomovirus (SqPB) disease syndrome. [ABSTRACT FROM AUTHOR]

Aesculus hippocastanum L. (European Horse-chestnut) constitutes a biogeographical relict species of the Balkan Peninsula, occurring in isolated and topographically distinct localities in Albania, Bulgaria, Greece and North Macedonia. Despite its great botanical, ornamental and pharmaceutical value, a thorough investigation of Ae. hippocastanum habitat diversity in its native distribution range has not been conducted yet. The present study aims at the syntaxonomic classification and ecological features of plant communities dominated by this species across its overall native distribution range. On the basis of 55 phytosociological relevés, five ecologically, floristically, and spatially well differentiated clusters were identified, with the main revealed gradients of differentiation being geographic location (longitude, latitude), altitude, annual precipitation and precipitation seasonality. The distinct microhabitats with a special refugial character where these plant communities occur meet the species' requirement for relatively high air and soil humidity. They have allowed the preservation of Ae. hippocastanum through time highlighting their great conservational value. The last one could be useful for the implementation of some appropriate measures for effective conservation of these communities. [ABSTRACT FROM AUTHOR]

This study explores plant communities dominated by the invasive species Fallopia x bohemica (Bohemian Knotweed) in Bulgaria. Using field data from 91 locations, an analysis identified the association Reynoutrietum japonicae within the alliance Aegopodion podagrariae. That association is recorded for the first time in Bulgaria. The vegetation is characteristically dominated by the Bohemian Knotweed species, which forms dense stands with low species richness. It mainly occurs in disturbed areas, such as riverbanks, roadsides and abandoned spots. This study contributes to understanding the distribution and composition of plant communities dominated by that invasive species. The negative impact of Bohemian Knotweed on the native flora and vegetation is also highlighted, with an emphasis on the need in control measures. [ABSTRACT FROM AUTHOR]

Paleoethnobotanical remains from basketry and cordage from the Paisley Caves offer an opportunity to explore how people engaged with plant communities over time. Fiber identification of textiles, together with radiocarbon dating, contributes new information about landscape use within the Summer Lake Basin. Expanded marshlands during the terminal Pleistocene / Early Holocene created suitable plant communities ideal for fiber technology, specifically wetland monocots and herbaceous dicots-including dogbane and stinging nettle-by 11,000 years ago. This technology is key to subsistence activities and craft production throughout the Holocene. Despite climatic events during the Middle Holocene, in which people transitioned from caves to sites centered on lakeshores and wetlands, the suite of fiber plants and their technological application remains constant. During the Late Holocene, bast fiber material diversified with the addition of flax and milkweed. The presence of flax in particular, a high-elevation plant, may reflect the increased use of upland root collection areas as populations increased. This research provides long-term data on culturally significant native plants used in the manufacture of fiber-based textiles over the last 14,000 years. [ABSTRACT FROM AUTHOR]

The gene-derived functional markers are considered effective to use in marker-assisted breeding and genetic diversity analysis. As of now, no functional markers have been identified from miRNAs regulating yield traits. The miRNAs play a key role as regulators in controlling the candidate genes involved in grain yield improvement in rice. In this study, 13 miRNA-SSR and their target gene SSR markers were mined from 29 yield-responsive miRNA along with their 29 target genes in rice. The validation of these markers showed that four miRNA-SSRs and one target gene SSR markers had shown polymorphism among 120 diverse rice genotypes. The PIC values ranged from 0.25 (OsARF18-SSR) to 0.72 (miR408-SSR, miR172b-SSR, and miR396f-SSR) with an average value of 0.57. These polymorphic markers grouped 120 rice genotypes into 3 main clusters based on the levels of high genetic diversity. These markers also showed significant association with key yield traits. Among all, miR172b-SSR showed a strong association with plant height in two seasons. This investigation suggests that this new class of molecular markers has great potential in the characterization of rice germplasm by genetic diversity and population structure and in marker-assisted breeding for the development of high-yielding varieties. [ABSTRACT FROM AUTHOR]

Ungulate grazing involves multiple components, including defoliation, dung and urine return, and trampling, which supply offsetting or synergistic effects on plant community composition and productivity (ANPP), but these effects have not been fully studied. Plant functional traits may reflect the response of plants to disturbance and their impact on ecosystem functions. Species turnover and intraspecific trait variation (ITV) are important drivers of community trait composition. We conducted a simulated grazing experiment in a steppe grassland in northern China to examine the effects of defoliation, dung and urine return, and trampling on community-weighted mean (CWM), functional diversity (FD) and ANPP, and to disentangle the roles of species turnover and ITV in driving these changes. We found that defoliation had a dominant effect on CWMs and FDs of all four traits through species turnover and ITV, respectively, resulting in a convergence of traits towards as more resource-acquisitive strategy. Dung-urine return resulted in more resource-acquisitive community traits mainly through ITV, whereas there were no significant effects on FDs except for leaf C/N. Trampling increased CWM of leaf dry matter content primarily driven by ITV, and had no significant effect on FDs. Furthermore, our simulated grazing positively affected ANPP, primarily due to nutrient additions from dung and urine, and ITV largely explained the variation in ANPP. These findings highlight the multifaceted effects of grazing components on community structure and ANPP, and the significance of ITV in shaping grassland plant communities and productivity. [ABSTRACT FROM AUTHOR]