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Over a century of research on pollinator cognition has shown that pollinators such as bees perceive and learn a multitude of floral stimuli and are capable of sophisticated decision-making using a variety of cognitive abilities. Research on pollinator cognition usually focuses on a single reward aspect in isolation, which does not reflect the complexity of reward types, chemistries, and attributes many pollinators encounter while foraging. Reward complexity can impact pollinators' perception, learning, and decision-making in interesting and sometimes unexpected ways. A cognitive perspective can shed new insight into the functions of floral reward complexity and bridge the fields of animal behavior and plant ecology. The cognitive ecology of pollination is most often studied using simple rewards, yet flowers often contain multiple types of chemically complex rewards, each varying along multiple dimensions of quality. In this review we highlight ways in which reward complexity can impact pollinator cognition, demonstrating the need to consider ecologically realistic rewards to fully understand plant–pollinator interactions. We show that pollinators' reward preferences can be modulated by reward chemistry and the collection of multiple reward types. We also discuss how reward complexity can mediate pollinator learning through a variety of mechanisms, both with and without reward preference being altered. Finally, we show how an understanding of decision-making strategies is necessary to predict how pollinators' evaluation of reward options depends on the other options available. [ABSTRACT FROM AUTHOR]

Dose–response curves hold promise in capturing environmental complexity. Conceptual developments now allow dose–response curves to be produced via syntheses of smaller studies. Dose–response meta-analyses should allow us to consider doses and responses that are laborious to assay. We present an example of a dose–response meta-analysis of how photoperiod alters mycorrhizal responsiveness. A large fraction of experimental work in plant ecology, and thus also on ecosystem functioning and the delivery of ecosystem services, describes experiments that have been carried out under controlled (glasshouse) conditions. Controlled growth settings commonly sacrifice realism through, for example, reducing the densities of plant species in the pots and controlling how environmental settings such as moisture and light vary in favor of a higher mechanistic resolution, which makes these studies particularly suitable for subsequent syntheses. We explore the possibility that further integration of dose–response curves can maximize the impact of existing studies. We suggest that we can expand considerably the scope of the dose and response variables that are considered in plant ecology. [ABSTRACT FROM AUTHOR]

• Specialised plant pollination systems can suffer reduced fertility if they receive insufficient pollinator service. • The Cape endemic Cyanella alba possess specialised floral adaptations – mirror-image flowers and dimorphic anthers – usually associated with buzz pollination by bees. • Experimental pollinations demonstrated that plants possess ovarian self-incompatibility and depend on pollinators for cross-pollination. • Chronic pollen limitation of seed set owing to the near absence of visitation by buzz pollinating bees was evident in several natural populations. • Land use and climate change may explain the paucity of buzz pollination with implications for ecology and evolution of plant populations. Plants with specialised pollination systems may be susceptible to reduced fertility if they are incapable of autonomous self-pollination and are visited infrequently by pollinators capable of promoting effective cross-pollination. Here, we investigate this question by examining the reproductive ecology of the Cape endemic Cyanella alba subsp. flavescens (Tecophilaeaceae), which has mirror-image flowers (enantiostyly) and dimorphic anthers (heteranthery). These traits are usually associated with buzz pollination mediated by bees that extract pollen from the poricidal anthers of flowers through vibration. We quantified insect visitation to flowers in three populations over two years in the vicinity of the Biedouw Valley, Western Cape, South Africa to determine whether plants were visited by buzz-pollinating bees. We also recorded visits by pollinators to other co-flowering species at each site and constructed a network on insect visitation. We conducted controlled hand pollinations and bagging experiments to determine whether plants were self-compatible and capable of autonomous self-pollination, and compared natural levels of fruit and seed set with those obtained from hand cross-pollination to evaluate evidence for pollen limitation of seed fertility. Despite 74 h of field observations, only two actively buzz-pollinating bees were recorded visiting flowers, although they were observed visiting other species in the community. The most frequent visitors to C. alba were opportunistic pollen-consuming beetles although we obtained no direct evidence that they were effective in promoting cross-pollination. Plants in each population exhibited chronic pollen limitation of seed set. Controlled pollinations demonstrated that plants were moderately self-sterile and incapable of autonomous self-pollination. Although fruit set was high following self-pollination, few seeds were evident within developing fruit. Observations of pollen-tube growth following controlled hand self- and cross-pollination revealed abundant pollen tubes at the base of styles in both treatments. Thus, self-sterility in C. alba probably results from late-acting ovarian self-incompatibility, and possibly also the abortion of developing seed due to inbreeding depression. We discuss the possible causes of scarce buzz pollination in C. alba and consider its ecological and evolutionary consequences. [ABSTRACT FROM AUTHOR]

Trait-based approaches in microbiome research can focus on species traits over identity, improving our understanding of microbiome functions in diverse environments. Functional traits, such as morphological, physiological, and chemical characteristics can predict ecological strategies of plant-associated microbes. Genome size in plants and microbes has physiological, ecological, and evolutionary implications to their growth, stress tolerance and nutrient acquisition; it may affect the size and outcomes of plant–microbe interactions. Variation in genome size impacts plant interactions with microbial communities. It can affect plant nutrient demand, carbon allocation, and exudation-mediated responses, leading to changes in microbiomes. Further studies integrating genomic traits into microbial ecology will help us to understand plant–microbe interactions and microbial evolution. Trait-based approaches have gained growing interest in studying plant–microbe interactions. However, current traits normally considered (e.g., morphological, physiological, or chemical traits) are biased towards those showing large intraspecific variations, necessitating the identification of fewer plastic traits that differ between species. Here, we propose using genome size (the amount of DNA in the nucleus of a cell) as a suitable trait for studying plant–microbiome interactions due to its relatively stable nature, minimally affected by external environmental variations. Emerging evidence suggests that plant genome size affects the plant-associated microbial community, and tissue-specific environments select microbes based on their genome size. These findings pinpoint environmental selection in genome size as an emerging driver of plant–microbiome interactions, potentially impacting ecosystem functions and productivity. [ABSTRACT FROM AUTHOR]

A sustainable future requires securing of the fundamental relationship between humans and biodiversity. This includes not only the conservation of biodiversity, but also the Indigenous and local knowledge (ILK) associated with it. Indigenous peoples and local communities (IPLCs) hold wide-ranging knowledge about plants and their ecology, properties, propagation, and cultivation from seed. ILK is globally threatened but rarely considered and conserved alongside ex situ seed collections, despite being key to the success of these collections. Co-conservation of biodiversity with ILK through support of IPLCs enhances conservation success and improves the prospects for the future uses of ex situ collections in worst-case scenarios such as extinction or in mitigating the negative impacts of climate change. Indigenous and local knowledge (ILK) holders have deep ecological, horticultural, and practical knowledge of plants, but this knowledge is not routinely considered and supported along with seed collections conserved ex situ. In this opinion, conceived collaboratively by a team of botanists, ecologists, ethnobiologists, and practitioners in biodiversity and ILK systems conservation, we propose seven actions towards the co-conservation of seeds and associated knowledge to overcome obstacles and encourage ex situ conservation institutions to support knowledge holders in multiple ways. Success depends on simultaneous changes in conservation practices, new collaborative relationships, and shifts in policy to share and conserve biocultural diversity. Failure to act will witness the continued erosion of ILK and depreciation of ex situ plant collections. [ABSTRACT FROM AUTHOR]

Plants can detect many features of their environment, including vibration. A plant's natural acoustic environment contains information potentially crucial to fitness, and recent work shows that natural acoustic stimuli can elicit relevant responses. We propose an experimental approach focused on what plant tissues experience, using methods that precisely measure and reproduce the actual acoustic energy received by the plant. This experimental approach provides a general framework for understanding how plants perceive and use acoustic energy in their environment. Many interactions of plants with the environment have an acoustic component, including the actions of herbivores and pollinators, wind and rain. Although plants have long been tested for their response to single tones or music, their response to naturally occurring sources of sound and vibration is barely explored. We argue that progress in understanding the ecology and evolution of plant acoustic sensing requires testing how plants respond to acoustic features of their natural environments, using methods that precisely measure and reproduce the stimulus experienced by the plant. [ABSTRACT FROM AUTHOR]

Plants can utilize the common mycorrhizal network (CMN) as a pathway for competition, enabling the suppression of other plants through an asymmetric distribution of resources. This study aimed to assess the competitive dynamics of CMN originating from adult Brachiaria brizantha plants, juvenile Heliocarpus popayanensis , and juvenile Cariniana estrellensis on the growth of seedlings of these three species. Plants and seedlings were cultivated in substrates containing native arbuscular mycorrhizal fungi (AMF). Analysis of variance was conducted, and means were compared using the Tukey test. The results indicated that seedling growth of all three species was significantly suppressed by the CMN originating from adult B. brizantha , moderately suppressed by the CMN from juvenile H. popayanensis , and weakly suppressed by the CMN from juvenile C. estrellensis. While the seedlings of B. brizantha initially experienced suppression, they eventually developed and suppressed the juvenile plants of both H. popayanensis and C. estrellensis , leading to a reversal of the nutrient flux. This shift corroborated the mechanism of reciprocal reward. The study observed the formation of a gradient in seedling suppression, with the strength of suppression inversely correlated with the advancement of ecological plant groups during succession. The establishment of the seedling suppression gradient was associated with variations in photosynthetic potential, mycorrhizal responsiveness, and root colonization intensity by AMF. The competition dynamics mediated by the CMN affect the composition and diversity of plant communities over time, reinforcing the importance of mycorrhizal interactions in plant ecology and ecosystem management, particularly in restoration and conservation contexts. • Occurrence of plant suppression gradients via CMN across ecological groups. • CMN strongly influences plant competition and resource distribution. • The negative impact of CMN from different adult plant species on seedling growth. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combination of ecological modelling and machine learning algorithms is a research hotspot; • Multivariate statistical analysis is promising in ecosystem building; • Machine learning can effectively underpin chemical fingerprinting in ecology; • Crossing disciplines between chemical analyses and ecological knowledge; • Constructing logical relationships between chemical fingerprinting, machine learning and ecology. With the rapid development of chromatography, spectroscopy and other detection techniques, chemical fingerprinting has become a powerful tool for ecology research. The data generated by these techniques contain a large amount of key information related to the molecular structure, and the optimization and study of these data using chemometrics and machine learning algorithms will have higher precision and accuracy. This paper reviews the analytical techniques used to generate chemical fingerprints in recent years and scrutinises the diversity of applications of chemical fingerprints in the field of plant ecology. Applications in combination with machine learning are emphasized. Prospects for chemical fingerprinting combined with machine learning in plant ecology include the development of fingerprinting databases for accurate species identification, and the integration of advanced techniques to incorporate fingerprinting techniques into ecological modelling to predict plant responses to environmental changes. These innovative avenues hold the promise of improving our understanding of plants and their complex interactions in various ecosystems and integrating them to advance ecological research. [ABSTRACT FROM AUTHOR]

Disturbance regimes related to water level fluctuation play an important role in the structuring of aquatic macrophyte communities. In managed systems, winter water level drawdowns have shown promise in controlling populations of nuisance macrophytes, however, drawdowns may have unintended negative consequences on erosion, fauna, and non-target plant species. The Chippewa Flowage, located in Sawyer County, WI, has implemented targeted winter water level drawdowns with the goal of reducing nuisance levels of Myriophyllum spicatum. To evaluate the effects of water level drawdowns on Myriophyllum spicatum and the native macrophyte community, we conducted repeated full lake surveys of aquatic macrophytes at 2018 points under drawdown and normal water level management in 2005/06, 2015, and 2017. We supplemented these efforts with downscaled surveys in 2007, 2010, and 2016. Surveys revealed a statistically significant decline in both Myriophyllum spicatum occurrence and abundance, and average macrophyte abundance during active drawdown management. Kernel distributions of change in point-specific c-value between the two time periods showed a significant increase under drawdown conditions, and a decrease under normal management (D = 0.41, P ≤0.0001). Drawdown management appeared to successfully control Myriophyllum spicatum abundance and allowed for improvements in the floristic quality of the macrophyte community but resulted in reduced macrophyte abundance overall. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are a widespread contaminant in the terrestrial environment, with potential impacts on the soil-plant system not yet well understood. This study explores the effects of oxidised low-density polyethylene-MPs (LDPE-MPs) on the rhizosphere ecology and plant fitness of Fragaria x ananassa (Duchesne ex Weston) Duchesne ex Rozier. The rhizospheric microbial community was investigated under the influence of 0,5 % LDPE-MPs by internal transcribed spacer (ITS) and 16 S rRNA metagenomic analysis; photosynthetic parameters, antioxidant enzyme activities, and nutrient accumulation were assessed to evaluate plant physiological and biochemical status. Genes related to jasmonic acid (JA), ethylene biosynthesis, and nitrate signalling pathways were analysed to define the plant molecular response. Our results showed a shift in the rhizosphere microbial community. We identified MPs molecular biomarkers in the contaminated rhizosphere (Fusarium, Thanatephorus and Pseudallescheria) with potential pathogenic functions and two novel molecular biomarkers (Ohtaekwangia and Ascobolus). MPs pollution negatively impacts plant fitness, which showed decreased chlorophyll a and b (40 and 48 %, respectively), a change in nutrient content (fluctuations between 14,42 and 26,7 %) at the leaf level and increased activity of antioxidant enzymes. Gene expression related to JA, ethylene biosynthesis, and nitrogen signalling pathways is enhanced in plants grown in contaminated soil, as well as the root endophytic and epiphytic microorganism interactions. Our results demonstrate that MPs pollution influences the rhizosphere microbial community and functions, and consequently, negatively impacts plant health. • Low-density polyethylene (LDPE) negatively impacts the rhizosphere-plant system. • LDPE soil contamination results in a rhizosphere microbial community shift. • Ascobolus and Ohtaekwangia are new microbial biomarkers of LDPE polluted soil. • LDPE affects transcription of genes related to several molecular pathways. • Mycorrhizal symbiosis enhanced in roots of plants grown in LDPE polluted soil. [ABSTRACT FROM AUTHOR]

Intraspecific trait variation has tremendous importance for species interactions and community composition. A major source of intraspecific trait variation is an organism's developmental stage; however, timing is rarely considered in studies of the ecological effects of intraspecific variation. Here, we examine the role of time in the ecology of intraspecific trait variation, focusing on plants and their interactions with other organisms. Trait variation due to differences in developmental timing has unique features and dynamics, distinguishing it from variation due to genes or the environment. When time is considered in studies of intraspecific trait ecology, the degree of variability in timing within a population becomes a key factor structuring trait-mediated ecological interactions and community processes. Trait variation within species is important for shaping ecological interactions and communities. Traits vary greatly through individual ontogenetic and phenological development, and individuals within populations vary in their developmental timing. Timing therefore must be important for understanding intraspecific trait variation and its effects on ecology. However, this is rarely considered in the field. A temporally explicit approach to the study of intraspecific trait variation in ecology is needed to fully understand population and community dynamics. [ABSTRACT FROM AUTHOR]

Domestication processes, amplified by breeding programs, have allowed the selection of more productive genotypes and more suitable crop lines capable of coping with the changing climate. Notwithstanding these advancements, the impact of plant breeding on the ecology of plant–microbiome interactions has not been adequately considered yet. This includes the possible exploitation of beneficial plant–microbe interactions to develop crops with improved performance and better adaptability to any environmental scenario. Here we discuss the exploitation of customized synthetic microbial communities in agricultural systems to develop more sustainable breeding strategies based on the implementation of multiple interactions between plants and their beneficial associated microorganisms. Domestication process and breeding programs, focused exclusively on the selection and improvement of specific plant traits, have negatively affected the recruitment and functionality of beneficial associations in agricultural systems. Rhizosphere and root-associated microorganisms play important roles in plant growth and resilience. Breeding programs aiming to rationally manipulate root traits in order to recruit beneficial microorganisms or to deter pathogens need to be developed. The development and application of synthetic communities ('SynComs') represent a sustainable way to improve plant growth and resilience. [ABSTRACT FROM AUTHOR]

Recent studies have cast new light on the intricate interplay between microbial biodiversity and plant functional traits, underscoring their pivotal roles in counteracting the adverse effects of anthropogenic biodiversity loss and climate change on ecosystem health. This critical review delves into the crucial support that microbial diversity offers for plant growth, soil health maintenance, and terrestrial ecosystem stability. It articulates the vital contributions of microbial diversity to plant functionality and ecosystem processes, marking a significant advancement in our understanding of these complex relationships. Subsequently, we present an analysis of cutting-edge research that sheds light on the dynamic interactions between microbial communities and plant traits. Highlighting the necessity for a deeper understanding, this review identifies key future research directions: (1) Exploring the role of microbe-microbe interactions in the rhizosphere and their impact on plant health and growth; (2) Investigating the influence of extreme weather events on microbe-plant symbioses; (3) Understanding the contribution of microbial communities to plant adaptation in marginal soils; (4) Assessing the impact of urbanization on plant-microbe interactions; and (5) Developing innovative approaches to harness the potential of plant-microbe interactions for sustainable agriculture. By proposing a comprehensive research agenda that melds microbial ecology with plant science, this synthesis emphasizes the indispensable role of microbial biodiversity in bolstering ecosystem resilience and functionality, aiming to pave the way for enhanced ecosystem management and conservation strategies. • Microbial diversity's role in nutrient cycling and plant health supports ecosystem productivity and resilience. • Land-use changes impact microbial diversity, altering plant traits and soil functions, needing tailored management. • Human activity impacts microbial diversity, requiring ecosystem-specific conservation for plant-microbe interactions. • Plant functional traits determine how plants affect and are affected by their microbial environment. • PSF and context dependency highlight the dynamic nature of plant-microbe interactions across environments. [ABSTRACT FROM AUTHOR]

Laticifers have been utilized as paradigms to enhance comprehension of specific facets of plant ecology and evolution. From the beginning of seedling growth, autonomous laticifer networks are formed throughout the plant structure, extending across all tissues and organs. The vast majority of identified products resulting from laticifer chemistry and metabolism are linked to plant defense. The latex, which is the fluid contained within laticifers, is maintained under pressure and has evolved to serve as a defense mechanism against both aggressors and invaders, irrespective of their capabilities or tactics. Remarkably, the latex composition varies among different species. The current goal is to understand the specific functions of various latex components in combating plant enemies. Therefore, the study of latex's chemical composition and proteome plays a critical role in advancing our understanding about plant defense mechanisms. Here, we will discuss some of these aspects. • Latex is constitutively present in all green parts of laticifer plants. • Latex-bearing plants have been studied as models for understanding plant defense. • The chemical composition of each latex fluid is unique. • Peptidases and chitinases are the most common constitutive proteins in latex. • Latex fluids also contain different types of toxic secondary metabolites. [ABSTRACT FROM AUTHOR]

• Centella asiatica presents morpho-anatomical adaptations to enhance energy gain efficiency in different environmental conditions. • Secretory canals are present in all Centella asiatica 's organs. • The presence of hydathodes was recorded for the first time in Centella asiatica. Restinga, a coastal sand environment, has low availability of organic matter, natural soil acidity, fast water drainage, high solar incidence, high salinity, strong winds and coastal flooding, which may require specific plant traits. This study analyzed the morphoanatomy of C. asiatica occurring in different microenvironments of Restinga and in an urbanized area to identify adaptive characteristics to each respective environment. Samples of roots, stolons, and leaves from sunny waterlogged dune slack, sunny wet dune slack, shaded wet dune slack, and shaded dry dune slack, and in an urbanized area were collected. Twenty three variables were measured, besides general histochemistry and soil characteristics. The one-way variance analysis (ANOVA) and principal component analysis (PCA) indicated that C. asiatica plants enhance different traits depending on the environment. Plants in shady microenvironments have greater petiole length, leaf area, fresh mass and leaf dryness compared to those occurring in sunny microenvironments. C. asiatica leaves are amphistomatic and in sunny microenvironments the chlorenchyma is more developed and has greater stomatal density on the abaxial surface. In urbanized areas, plants showed increased leaf area and fresh mass, and petiole thickening, and decreased leaf blade thickening. These traits may be related to the clay soil, which has greater water retention, and also to the shaded environment. Such adaptations allow the C. asiatica plants to maximize energy gain under different environmental conditions. Secretory canals were identified in all analyzed organs, which secreted acidic and neutral polysaccharides. We recorded for the first time the presence of hydathodes on the serrated margins of C. asiatica leaf blades. This study expands the knowledge on species occurring in coastal sand environments and the modifications presented to survive in distinct microenvironments of Restinga. [ABSTRACT FROM AUTHOR]

Traditional methods, such as direct observations or manually photographing bait stations, are limited in both data collection efficiency and accuracy. Consequently, they fail to capture the dynamic changes and complex relationships between ant species. We developed a novel system as a potential solution that combines processed consumer-grade camera equipment and software that acquires data needed for in situ experiments. This software features a user-friendly graphics user interface (GUI) for data collection and post-hoc analysis from videos captured by the camera equipment. Researchers can use this system to (1) count species abundance per frame; (2) calculate species speed; (3) detect ant interactions; and (4) count the abundance of different subcastes within species on baits. To demonstrate the complete workflow, we applied this system on ant videos collected in Hong Kong. Practical guides (supplement materials) detailing suggestions for camera equipment and software operations in both field and laboratory studies are provided. We present the results of ten in situ experiments of ants (each lasting 1–1.5 h) conducted in Hong Kong though processed consumer-grade camera equipment, with videos analyzed using the newly developed software. The analysis captured a range of variables related to ant foraging behavior, including resource discovery time, nestmate recruitment rate, and interspecific interactions. Our results confirm that the developed software provides an integrated and efficient approach for data collection, extraction, and analysis in in situ experiments, enhancing the capabilities of insect ecology research. • Comprehensive and accurate data collection and analyses informing on insect foraging patterns. • Post-analysis using object detection provides new datasets for in situ experiments. • The Ant-Observer software streamlines data collection, extraction, and analyses. [ABSTRACT FROM AUTHOR]

Microbes orchestrate nearly all major biogeochemical processes. The ability to program their influence on plant growth and development is attractive for sustainable agriculture. However, the complexity of microbial ecosystems and our limited understanding of the mechanisms by which plants and microbes interact with each other and the environment make it challenging to use microbiomes to influence plant growth. Novel technologies at the intersection of microbial ecology, systems biology, and bioengineering provide new tools to probe the role of plant microbiomes across environments. Here, we summarize recent studies on plant and microbe responses to abiotic stresses, showcasing key molecules and micro-organisms that are important for plant health. We highlight opportunities to use synthetic microbial communities to understand the complexity of plant–microbial interactions and discuss future avenues of programming ecology to improve plant and ecosystem health. [Display omitted] Influences of abiotic stresses on assembly and function of rhizo-microbiome How ecology shapes plant and microbial stress resilience Examples in which microbial abiotic stress responses directly impact plant health SynComs as powerful tools for understanding complex microbiome-driven ecosystems Prospects of synthetic ecology to program inter-kingdom interactions [ABSTRACT FROM AUTHOR]

• Western Tasmania is climatically suitable for forests. • Forested areas in this region contain large expanses treeless sedgelands. • Sedgelands are more fire prone than forests. • Sedgelands have organic, poorly drained, and infertile soils. • Forests have mineral, well drained and nutrient rich soils. • Edaphic factors, not fire, are the primary cause of the sedgeland-forest mosaics. An unresolved, key question in plant ecology and biogeography is the relative importance of fire disturbance and edaphic factors in controlling treeless-forest boundaries. We investigated the similarities and differences in soil physical and chemical characteristics in Sedgeland, Scrub and Eucalyptus Forest sites in and around a large treeless area (Blakes Opening) situated in the densely forested Huon Valley in southern Tasmania. In each community, fire risk was also assessed over 12 months using microclimate measures of above-ground temperature and humidity, and water tables were monitored seasonally. Sedgeland soils and the upper layer of Scrub soils were organic (18–38 % C) and sand rich (c. 75 % of the mineral fraction), and differed fundamentally from the inorganic Forest soils (c. 5 % C and 55 % sand). Sedgeland soils had a much lower bulk density and a significantly lower concentration and capital of most plant nutrients (except C, N and S) in the rootzone. Ordinations of both soil and rocks in the profiles discriminated the Sedgeland and Forest, with the Scrub being intermediate. In winter, water tables were higher in Sedgeland than Forest and Scrub. However, Sedgeland has a drier microclimate, which makes its fine fuels available to burn more frequently and for a longer period over the summer compared with Forest. This was confirmed by radiocarbon dating of soil charcoal, which showed that fire was a regular feature of this environment throughout the Holocene. The strong edaphic differentiation of Sedgeland-Forest boundaries at Blakes Opening calls into question a prominent theory that vegetation patterns in this region are shaped primarily by landscape fires. [ABSTRACT FROM AUTHOR]

• NEON plant diversity data are not ready for most ecological analysis out of the box. • neonPlantEcology is an R package for accessing and formatting these data. • It aggregates to 5 spatial and 3 temporal scales aligned with the sampling design. • It provides functions for a workflow from raw data to analysis-ready data. The National Ecological Observatory Network (NEON) is a continental-scale endeavor of ecological data collection for 30 years. We created a software package, neonPlantEcology that automatically arranges the raw data from the plant presence and percent cover (DP1.10058.001) data product from NEON into tables familiar to plant ecologists. Because of the broad scale of the observatory, it is necessary to tailor the data collection to the idiosyncrasies of each of 47 different ecosystems. Furthermore, data collection practices are occasionally modified for various reasons. These complexities, along with the volume and multiscalar nature of the data, need to be understood and accounted for in order to correctly process the data. This is particularly true for the plant diversity data product. We present three case studies using the package, centered around the three primary functions of neonPlantEcology. By automating the process of preparing NEON's plant diversity data, neonPlantEcology makes it more accessible to a wide range of users. [ABSTRACT FROM AUTHOR]

A longstanding research divide exists in plant ecology: either focusing on plant clonality, with no ambition to address nonclonal plants, or focusing on all plants, ignoring that many ecological processes can be affected by the fact that some plants are clonal while others are not. This gap cascades into a lack of distinction and knowledge about the similarities and differences between clonal and nonclonal plants. Here we aim to bridge this gap by identifying areas that would benefit from the incorporation of clonal growth into one integrated research platform: namely, response to productivity and disturbance, biotic interactions, and population dynamics. We are convinced that this will provide a roadmap to gain valuable insights into the ecoevolutionary dynamics relevant to all plants. Clonal plants can represent a substantial proportion of species in floras and plant communities. Because they share several functions that are not present in nonclonal plants, the differences in their proportions are likely to scale up as community and ecosystem differences. Clonal reproduction is provided by specialized organs that directly or indirectly affect other plant traits. Clonal growth organs usually serve for the storage of carbohydrates and the buildup of the bud bank, both necessary for resprouting in recurrently disturbed habitats. These storage organs affect global carbon cycling. Clonal growth leads to increased plant size in the horizontal dimension and to different degrees of ramet aggregation that influence the exploration of soil resources, pollination, and biotic interactions. Clonal growth serves as a reproductive insurance mechanism that further affects plant demography and possible evolutionary rates. [ABSTRACT FROM AUTHOR]

Plants have evolved numerous strategies to acquire poorly available nutrients from soil, including the release of carboxylates from their roots. Silicon (Si) release from mineral dissolution increases in the presence of chelating substances, and recent evidence shows that leaf [Si] increases markedly in old phosphorus (P)-depleted soils, where many species exhibit carboxylate-releasing strategies, compared with younger P-richer soils. Here, we propose that root-released carboxylates, and more generally rhizosphere processes, play an overlooked role in plant Si accumulation by increasing soil Si mobilisation from minerals. We suggest that Si mobilisation is costly in terms of carbon but becomes cheaper if those costs are already met to acquire poorly available P. Uptake of the mobilised Si by roots will then depend on whether they express Si transporters. The pivotal role of Si in plant biology and ecology is increasingly acknowledged, but the factors involved in plant Si accumulation have received little attention in the context of nutrient-acquisition strategies. Leaf [Si] increases with declining soil P availability in environments where many species exhibit carboxylate-releasing strategies to acquire soil P. This coincides with an increase in leaf [Mn], a proxy for carboxylate-releasing strategies. Plant defences based on Si accumulation are thought to incur lower C costs than C-based defences, but this does not acknowledge the costs required to mobilise Si in the rhizosphere. Rhizosphere processes making Si available for plant uptake should be considered to understand the major variation of leaf [Si] among terrestrial plants, especially in environments with low plant-available [Si], in addition to considering expression of Si transporters. [ABSTRACT FROM AUTHOR]

In plant ecology, community-weighted trait means are often used as predictors for ecosystem functions. More recently, also within-species trait variation has been confirmed to contribute to ecosystem functioning. We here go even further and assess within-individual trait variation, assuming that every leaf in a plant individually adjusts to its micro-environment. Using forest plots varying in tree species richness (Sardinilla experiment, Panama), we analysed how leaf traits within individual trees vary along the vertical crown gradient. Furthermore, we tested whether niche partitioning in mixed stands results in a decrease of within-species leaf trait variation and whether niche partitioning can be also observed at the level of individual trees. We focused on leaf traits that describe the growth strategy along the conservative-acquisitive spectrum of growth. We found a decrease in within-species variation of specific leaf area (SLA) with increasing neighbourhood species richness. Both sampling height and local neighbourhood richness contributed to explaining within-species leaf trait variation, which however, varied in importance among different species and traits. With increasing sampling height, leaf dry matter content (LDMC), carbon to nitrogen ratio and lignin content increased, while leaf nitrogen concentration (leaf N), SLA, cellulose and hemicellulose decreased. Variation in leaf N decreased with increasing neighbourhood species richness, while the magnitude of within-individual variation of most traits was unaffected by neighbourhood species richness. Our results suggest an increased niche partitioning with increasing species richness both in a plant community and at the level of individual plants. Our findings highlight the importance of including within-individual trait variation to understand biodiversity-ecosystem functioning relationships. [ABSTRACT FROM AUTHOR]

• Distance sampling methods are very suitable for sampling tree diversity. • No more than 20% of all trees need to be measured, often less. • T-square sampling adapts to different patterns of tree locations. • T-square sampling decreases sample size or increases accuracy. • Sampling error of species mingling and size differentiation depends on underlying spatial pattern. • Use of uniform angle index, species mingling and size differentiation can be recommended for distance sampling. Distance sampling and its statistically improved variant, T-square sampling, are important sampling methods in plant ecology. They have often been applied in the context of plant density estimations and are comparatively easy to implement, since they intuitively follow the nearest-neighbour principle and thus do not require the layout of sample plots. Previous research studying distance sampling suggested that T-square sampling may also lead to an improved estimation of spatial tree diversity indices. We simulated distance and T-square sampling in six large fully mapped forest areas for seven tree diversity indices of which some competed for the same diversity aspect, i.e. tree location (dispersion), tree species and tree size diversity. Our results demonstrated that both distance and T-square sampling are indeed robust methods for sampling spatial measures of tree diversity. The sample size required for a sampling error of 10% does not exceed 20% of the total number of trees in a sampling area. T-square sampling has the ability to adapt to different spatial patterns of tree locations and this ability is key to the way the method controls estimation bias. The sample size required for species mingling and size differentiation clearly depends on the underlying spatial tree pattern in the sampling area. With most diversity indices, sample size reductions between 0.06% and 40% could be achieved by the application of T-square sampling compared to traditional distance sampling. All other conditions being equal, we could identify the uniform angle index, the species mingling index and the size differentiation index as those diversity indices achieving lower sampling error values than their competitors. For tree density estimations the Diggle and Byth estimators performed best. Based on our results, T-square sampling can be considered a robust sampling method for spatial tree diversity indices that is easy to apply in the field. [ABSTRACT FROM AUTHOR]

In plant ecology, community-weighted trait means are often used as predictors for ecosystem functions. More recently, also within-species trait variation has been confirmed to contribute to ecosystem functioning. We here go even further and assess within-individual trait variation, assuming that every leaf in a plant individually adjusts to its micro-environment. Using forest plots varying in tree species richness (Sardinilla experiment, Panama), we analysed how leaf traits within individual trees vary along the vertical crown gradient. Furthermore, we tested whether niche partitioning in mixed stands results in a decrease of within-species leaf trait variation and whether niche partitioning can be also observed at the level of individual trees. We focused on leaf traits that describe the growth strategy along the conservative-acquisitive spectrum of growth. We found a decrease in within-species variation of specific leaf area (SLA) with increasing neighbourhood species richness. Both sampling height and local neighbourhood richness contributed to explaining within-species leaf trait variation, which however, varied in importance among different species and traits. With increasing sampling height, leaf dry matter content (LDMC), carbon to nitrogen ratio and lignin content increased, while leaf nitrogen concentration (leaf N), SLA, cellulose and hemicellulose decreased. Variation in leaf N decreased with increasing neighbourhood species richness, while the magnitude of within-individual variation of most traits was unaffected by neighbourhood species richness. Our results suggest an increased niche partitioning with increasing species richness both in a plant community and at the level of individual plants. Our findings highlight the importance of including within-individual trait variation to understand biodiversity-ecosystem functioning relationships. [ABSTRACT FROM AUTHOR]

It is generally accepted that plants locally influence the composition and activity of their rhizosphere microbiome, and that rhizosphere community assembly further involves a hierarchy of constraints with varying strengths across spatial and temporal scales. However, our knowledge of rhizosphere microbiomes is largely based on single-location and time-point studies. Consequently, it remains difficult to predict patterns at large landscape scales, and we lack a clear understanding of how the rhizosphere microbiome forms and is maintained by drivers beyond the influence of the plant. By synthesizing recent literature and collating data on rhizosphere microbiomes, we point out the opportunities and challenges offered by advances in molecular biology, bioinformatics, and data availability. Specifically, we highlight the use of exact sequence variants, coupled with existing and newly generated data to decipher the rules of rhizosphere community assembly across large spatial and taxonomic scales. The processes shaping rhizosphere microbial communities are currently unclear because of both a lack of knowledge about biogeographical patterns and the disconnection between plant and microbial scales. Sequence databases have now collected a sufficient amount of data covering a range of biomes and plant taxa to allow synthesis across studies. Recently, new bioinformatic methods have been developed that allow us to overcome former spatial and taxonomic limitations. Understanding the processes that shape rhizosphere microbial communities will provide important insights into plant ecology and evolutionary biology, and can enable us to manage microbial and plant ecosystem services. [ABSTRACT FROM AUTHOR]

While scholars have developed a nuanced understanding of agriculture as a form of care, the temporal organization of farming practices has received little consideration. Focusing on how farmers organize and experience agriculture, we track diverging approaches to care work on urban farms in Vilnius, Lithuania. Our ethnographic fieldwork and interviews show how Lithuanian urban farmers are struggling to reconcile the civic ideals of the global urban farming movement with their historical understandings of care for specific plants and the land. Whereas the older generation views farming as kinship-based individualized work focusing on particular plants and garden ecologies, the younger generation approaches it as a way to unwind, mediate, and build a community. These different perspectives on farming translate into divergent temporalities of care in which productivist goals rooted in socialist self-provisioning practices and embodied in orderly landscapes encounter new trends of agricultural care manifested in the natural aesthetics of the farms. We examine dynamic tensions between the two farming modalities by linking them to different understandings of moral commitments and responsibilities for plants and land. Through the lens of temporality, we also show how these divergent care modes are themselves grounded in gender inequalities reproduced on the farms and enabled by by the welfare state institutions, including maternity leave and retirement policies. [ABSTRACT FROM AUTHOR]

Plants are the largest biomass component of most terrestrial ecosystems, and litter decomposition is considered the dominant process by which nutrients return to plants. We show that in terrestrial ecosystems, there are three major pathways by which plant biomass is degraded into forms that release nutrients again available to plants: microbial decomposition; vertebrate herbivory; and wildfires. These processes act at different spatial and temporal scales, have different niches, and generates different ecological and evolutionary feedbacks. This holistic view in which microbes, herbivores, and wildfires play a joint role in the functioning of ecosystems contributes to a better understanding of the diversity of mechanisms regulating the biosphere. There are three major ways to recycle organic matter and nutrients in terrestrial ecosystems: microbial decomposition; vertebrate herbivory; and wildfires. Each has different requirements, acts at different spatial scales, and occupies different (although overlapping) environmental niches. The three recycling pathways generate different feedbacks and contribute to the ecology and evolution of plants, and to global biogeochemical cycles. [ABSTRACT FROM AUTHOR]

Terrestrial Laser Scanning (TLS) has been increasingly used in forestry applications including forest inventory and plant ecology. Tree biophysical properties such as leaf area distributions and wood volumes can be accurately estimated from TLS point clouds. In these applications, a prerequisite is to properly understand the information content of large scale point clouds (i.e., semantic labelling of point clouds), so that tree-scale attributes can be retrieved. Currently, this requirement is undergoing laborious and time consuming manual works. In this work, we jointly address the problems of semantic and instance segmentation of forest point clouds. Specifically, we propose an unsupervised pipeline based on a structure called superpoint graph, to simultaneously perform two tasks: single tree isolation and leaf-wood classification. The proposed method is free from restricted assumptions of forest types. Validation using simulated data resulted in a mean Intersection over Union (mIoU) of 0.81 for single tree isolation, and an overall accuracy of 87.7% for leaf-wood classification. The single tree isolation led to a relative root mean square error (RMSE%) of 2.9% and 19.8% for tree height and crown diameter estimations, respectively. Comparisons with existing methods on other benchmark datasets showed state-of-the-art results of our method on both single tree isolation and leaf-wood classification tasks. We provide the entire framework as an open-source tool with an end-user interface. This study closes the gap for using TLS point clouds to quantify tree-scale properties in large areas, where automatic interpretation of the information content of TLS point clouds remains a crucial challenge. [ABSTRACT FROM AUTHOR]

• Estimating missing Ellenberg Indicator Values (EIV) could help plant ecology studies. • We tested and compared several methods for estimating missing EIV from existing data. • Multiple Linear Regression and k-Nearest Neighbour performed better than the others. • Statistical methods are more effective than imputation based on expert knowledge. • This approach would greatly facilitate monitoring species with unknown EIV. Ellenberg indicator values (EIV) are widely used in vegetation ecology, but the values for many species in Southeastern Europe are not available due to incomplete knowledge of their ecology: it is therefore of paramount importance to estimate missing values in existing databases. The entire EIV set for a single species can be missing or a single EIV can be missing for species for which other indicator values are available. Our aim here is to provide a simple method to impute missing values for species who have missing data in a single or multiple EIV. For this purpose, we adopt a multiple imputation procedure and compare a number of imputation methods on the basis of two datasets: i) "indices", the set of 9 Ellenberg indicators taken from literature, available for 10,824 species and ii) "vegetation", a set describing the physical and climatic characteristics (Light, Temperature, Continentality, Soil moisture, Nitrogen, Soil pH, Hemeroby index, Humidity, Organic_matter) of 29,935 relevés from Southeastern Europe where at least one tree species is present. The imputation methods we considered are: k-Nearest Neighbour, multiple linear regression (with or without collinearity correction), Reprediction Algorithm, Weighted Averaging (WA) and Weighted Averaging Partial Least Squares (WAPLS) regression. The different methods of imputation were compared by looking at the output produced and its deviation from the "true" observed values for a set of species with known EIVs. We have considered a set of species with known EIVs and proceeded to multiple imputation using the methods above; as a measure of performance we adopted the mean squared error (MSE) estimate, and expert judgement of ecological consistency. Models based on Regression and k-Nearest Neighbour seem to outperform the others. On the contrary, Reprediction algorithm in its different forms: produced less satisfactory results. Imputation of missing values is generally based on expert knowledge or on some variant of weighted averaging (also known as Hill's method). Here we show that other methods may be more effective and should be appropriately considered by vegetation scientists, since those may allow the application of EIVs in other biogeographic regions. [ABSTRACT FROM AUTHOR]

A central issue in plant ecology is exploring universal rules and the mechanisms under which photosynthetic energies are allocated to different organ parts. Until recently, prevalent studies focused on testing either optimal allocation theory or allometric allocation theory in predicting plant biomass partitioning patterns. However, paying much attention to the stable state prevents the development of new biomass allocation theories in transient time scales. Here, based on theories in transients and the allometric relationships in plant traits, I develop general theoretical models to study the transient perturbations of plant biomass allocated to non-photosynthetic organ parts. With both simulation and empirical approaches, I investigate the effect of plant stem diameter at breast height (DBH) on the variation of biomass allocation patterns during plant ontogeny. Results show that increases in DBH can mitigate the magnitude of the perturbations of plant biomass and biomass fractions allocated to both plant stem and root parts. The findings are robust when either deterministic or stochastic models are conducted. Moreover, empirical analyses from a large forest database in Eurasia consistently support the predictions from the theoretical frameworks. In this paper, I draw attention to the transient allocation pattern of plant biomass for non-photosynthetic organs, and I find the significant role of DBH. This work has important implications in both theoretical breakthroughs and practical applications. It not only provides the foundation to test new biomass allocation hypotheses but also directs agricultural and forest management to achieve stabilized yields. • Plant biomass allocation patterns focus on allometic and optimal theories. • Limitations in stable state prevent insight into their transient dynamics. • Stem diameter at breast height regulate the variation in biomass fractions. • Studies provide implications of stabilizing yields in forest management. [ABSTRACT FROM AUTHOR]

Understanding and reversing biodiversity decline in the Anthropocene requires robust data on species taxonomic identity, distribution, ecology, and population trends. Data deficits hinder biodiversity assessments and conservation, and despite major advances over the past few decades, our understanding of bee diversity, decline and distribution in Europe is still hampered by such data shortfalls. Using a unique digital dataset of wild bee occurrence and ecology, we identify seven critical shortfalls which are an absence of knowledge on geographic distributions, (functional) trait variation, population dynamics, evolutionary relationships, biotic interactions, species identity, and tolerance to abiotic conditions. We describe "BeeFall," an interactive online Shiny app tool, which visualizes these shortfalls and highlights missing data. We also define a new impediment, the Keartonian Impediment, which addresses an absence of high-quality in situ photos and illustrations with diagnostic characteristics and directly affects the outlined shortfalls. Shortfalls are highly correlated at both the provincial and national scales, identifying key areas in Europe where knowledge gaps can be filled. This work provides an important first step towards the long-term goal to mobilize and aggregate European wild bee data into a multi-scale, easy access, shareable, and updatable database which can inform research, practice, and policy actions for the conservation of wild bees. [ABSTRACT FROM AUTHOR]

There is a crucial need for tools to help researchers, technicians and farmers designing sustainable agroecosystems based on agroecology Indeed, such agroecosystems are inherently complex and their design requires to integrate various data and unstabilised scientific knowledge. In this paper, we consider the issue of selecting service plant species according to their potential to provide ecosystem services. To tackle that issue, we adopt an approach based both on a formalized representation of domain knowledge, which enables reasoning, and on the exploitation of available data, collected independently of the targeted application. More specifically, we rely on the one hand on recent scientific results in agronomy linking functional traits (i.e., measurable characteristics of plant species) to ecosystem services, and on the other hand on data about functional traits collected by the research community in ecology. The architecture of our system is inspired by the ontology-based data access paradigm, which allows to combine data and knowledge in a principled way. We provide a methodology to acquire scientific knowledge in the form of diagrams linked to data sources, as well as a formalization in a logical rule-based language. Importantly, our rules are independent from specific diagrams and data, to ensure genericity and facilitate the evolution of the system. We detail the construction of a knowledge base devoted to vine grassing, i.e., installing herbaceous service plants in vineyards, and present an evaluation of the system's results on this use case. We finally discuss the lessons learned and further challenges to be met. • Plant functional traits can be linked to ecosystem services (ES) using a logical rule-based language. • An ontology-based data access approach enables to identify the most relevant species for a desired ES. • The management of missing and redundant trait values in databases is key to the reliability of species selection. • The proposed tool ranks service plant species similarly to published and expert knowledge. [ABSTRACT FROM AUTHOR]

• The study of plant–plant parasitism has experienced remarkable growth in the scientific literature. • Research on plant parasites has predominantly focused on ecological and physiological aspects in the last 20 yeras. • Aspects of evolution and host-parasite interactions needs further and deeper investigations. • We hope this special issue will serve as a catalyst for further advancements in the investigation of plant-plant parasitism. The study of plant–plant parasitism has experienced remarkable growth in the scientific literature, particularly over the past two decades. Hemi- and holoparasites, in particular, have been recognized as pivotal components within plant communities, capable of upscale effects to the ecosystem. Research on plant parasites has predominantly focused on ecological and physiological aspects of parasites and hosts, with a global distribution pattern. However, some fields remain relatively unexplored, and specific regions of Asia and the Global South (with exception of Australia and Brazil) have yet to receive comprehensive attention. Here, we introduce the theme on plant hemi- and holoparasites and explore publication trends on plant–plant parasitism over the past half-century, with a particular emphasis on papers published within the last two decades. We explore our findings to extend an invitation to researchers from diverse backgrounds and disciplines to contribute their expertise to a forthcoming Virtual Special Issue of Flora – Morphology, Distribution, Functional Ecology of Plants on "Plant Parasitism: Ecology, Evolution and Functional Aspects", with contributions expected from a wide range of topics related to ecology, physiology, morphology, systematics, and reproductive biology. We believe that this special issue will help in advancing our knowledge in plant-plant parasitism, fostering collaboration and facilitating the growth of this exciting area of research. [ABSTRACT FROM AUTHOR]

Wetlands play a crucial role in oxygen production, air purification, and quality maintenance. Thus, conservation of wetland is essential in response to natural and anthropogenic damaging activities. Restored farmland, utilized to repair the southern buffer zone of Jiangsu Yancheng Wetland National Nature Reserve for Rare Birds, was used to investigate and analyze the diversity of migratory birds and soil fauna. In this study, five different crops, colza oil, mustard, Chinese cabbage, wheat, and barley, were planted in the restored plots, which were foraged by overwintering migratory birds, resulting in low crop yield. The soil fauna biodiversity and biomass in the wheat, Chinese cabbage, and colza oil plots during winter were relatively rich, which attracted many migratory birds to roost and feed. The variability and population of migratory birds significantly improved (18 species and 164231 migratory birds), which was owed to soil fauna and planted crops. Therefore, based on the results of our study, farmland restoration could significantly enrich the biodiversity of soil fauna and migratory birds, improve the ecological environment of wetlands, and attract more migratory birds as inhabitants. [Display omitted] [ABSTRACT FROM AUTHOR]

Geoxyles are plants with massive underground and diminutive aboveground parts and in sub-Saharan Africa this life form is most diverse in south-central Africa. However, little is known about the population ecology of these plants, especially in south-central Africa. The purpose of this research was to investigate the demography and biomass structure of Lannea edulis , a widespread geoxyle in south-central Africa, using census, phenology and biomass data obtained over a 20-year period at a site in central Zambia, southern Africa. Mast fruiting in L. edulis is rare and seed germination rate and seedling mortality vary from year to year, resulting in episodic recruitment of juveniles into the population. Juvenile plants have a tuberous fleshy root that is transformed into a thick-barked woody taproot in adults. Frequent dieback of aerial shoots due to fire and herbivory induces the formation and growth of subsurface stems. The average oven-dry biomass of a L. edulis plant was 370 g of which shoots and roots represented 10% and 90%, respectively, thereby confirming that this geoxyle has indeed massive belowground parts. The demography of L. edulis is greatly influenced by variable annual recruitment of juveniles into the population and large individuals were estimated to live for more than 60 years. • Census and biomass data were used to study Lannea edulis population structure. • Abundant fruiting and juvenile recruitment in Lannea edulis are rare. • Juvenile fleshy tuberous roots develop into thick-barked woody taproots in adults. • Frequent dieback of aerial shoots induce the formation of subsurface stems. • Shoots and roots contribute 10% and 90%, respectively, to plant biomass. [ABSTRACT FROM AUTHOR]

Invasion of the exotic cordgrass, Spartina alterniflora , has become a global crisis and its spread is leading to significant alterations in the functions of ecosystems. However, alteration in nutrient levels caused by invasion of non-native plant species is poorly understood, and the effects of invasive plants on sediment nutrients found in previous studies are contradictory. In this study, we hypothesized that an exotic plant species invasion will change the chemical characteristics of an ecosystem over time. To test this hypothesis, the spatial distribution of S. alterniflora in 2006, 2010 and 2014 was analyzed by aerial images, Google Earth satellite images and field investigations. Furthermore, according to the space–time reciprocal principle, a primary field survey with three locations (S1, S2 and S4) was conducted in 2014, and sediment nutrient levels, including total carbon (TC), total nitrogen (TN) and total phosphorus (TP) were quantified to investigate the invasive effects of S. alterniflora. We also investigated six locations (S1–S6) in 2016 in the same manner to compare the changes in sediment nutrients between the two years. The area infested with S. alterniflora increased from 10.8 ha in 2006, to 26.2 ha in 2010, and 37.5 ha in 2014, with a 35.6% annual expansion rate between 2006 and 2010, and a 10.8% annual expansion rate between 2010 and 2014, respectively. Considering the two field survey results, we found that S. alterniflora invasion increased sediment nutrient levels in the early-term (i.e., S1–S4 period, approximately 10 years), and then significantly decreased TC, TN and TP content to levels even lower than bare beach. Analyses of stoichiometry characteristics of the sediment nutrients also verified these two apparent stages. The results showed that early-term invasion of S. alterniflora and subsequent invasion alter sediment nutrients differently, and these results may explain the seemingly contradictory increases and decreases in nutrient levels reported in previous studies. Our results provide important information that furthers our understanding of the impact of S. alterniflora invasion. • The annual expansion rate of S. alterniflora was 35.6% in 2006–2010. • The annual expansion rate of S. alterniflora was 10.8% in 2010–2014. • Early-term invasion of S. alterniflora increased sediment TC, TN and TP. • Subsequent invasion about 10 years later decreased sediment nutrients. • TC, TN and TP were significantly related to C;N ratio. [ABSTRACT FROM AUTHOR]

• Microbiota are important for plant growth, health and stress resilience. • Inoculation with key microbiota members can improve plant traits. • Tailored selection and delivery of microbial strains or consortia is required. • Microbiome improvement may be achieved by appropriate agro-management practices. • Plant breeding for improved interaction with microbiota will be of benefit. Plants have evolved with a plethora of microorganisms having important roles for plant growth and health. A considerable amount of information is now available on the structure and dynamics of plant microbiota as well as on the functional capacities of isolated community members. Due to the interesting functional potential of plant microbiota as well as due to current challenges in crop production there is an urgent need to bring microbial innovations into practice. Different approaches for microbiome improvement exist. On the one hand microbial strains or strain combinations can be applied, however, field success is often variable and improvement is urgently required. Smart, knowledge-driven selection of microorganisms is needed as well as the use of suitable delivery approaches and formulations. On the other hand, farming practices or the plant genotype can influence plant microbiota and thus functioning. Therefore, selection of appropriate farming practices and plant breeding leading to improved plant-microbiome interactions are avenues to increase the benefit of plant microbiota. In conclusion, different avenues making use of a new generation of inoculants as well as the application of microbiome-based agro-management practices and improved plant lines could lead to a better use of the plant microbiome. This paper reviews the importance and functionalities of the bacterial plant microbiome and discusses challenges and concepts in regard to the application of plant-associated bacteria. [ABSTRACT FROM AUTHOR]

Lichens, symbiotic organisms consisting from mycobionts (fungi) and photobionts (algae and/or cyanobacteria), play a substantial role in boreal coniferous forests. They may form thick mat that significantly interferes with young plants, mosses and rest of understory vegetation. Lichens synthesize more than one thousand of secondary metabolites, from which usnic acid is one of the most abundant. It can negatively affects plant metabolism through allelopathy. Lichen secondary metabolites can be a source of energy for soil microorganisms and at the same time, they can inhibit growth of surrounding competitive lichens, mosses and vascular plants. Lichen metabolites were also found in bark, xylem and leaves of some trees, which serving to epiphytic lichens as substrate. Although significant results, which deepening our knowledge in this area of research, were obtained during the last decades, understanding of role of lichens in boreal forests is very complex issue and requiring further studies. • Lichens form important part of vegetation in boreal forests. • They produce more than one thousand of unique secondary metabolites. • Lichen compounds posse many biological and ecological roles. • Secondary metabolites of lichens can be potent allelochemicals in the environment. [ABSTRACT FROM AUTHOR]

• Soil properties and crop pests affect pollination contribution to yield. • Pollination and concomitant services often display synergistic relationships. • Crop traits might influence plant response to resource and pollen availability. Insect pollination is a well-studied ecosystem service that supports production in 75% of globally important crops. Although yield is known to be sustained and regulated by a bundle of ecosystem services and management factors, the contribution of pollination to yield has been mostly studied in isolation. Here, we compiled and reviewed research on the contribution of pollination to crop yield under different environmental conditions, where the potential interaction between pollination and other factors contributing to yield, such as nutrient availability and control of pests, was tested. Specifically, we explored whether pollination displayed synergistic, compensatory or additive effects with concomitant factors. The literature search resulted in 24 peer-reviewed studies for a total of 39 individual tests of interactions. Studies examined responses in 13 crops testing interactions both at the local and the landscape scale. Interactions between pollination and other factors influencing yield were observed for several crops and mostly displayed positive-synergistic relationships. Crop life-history traits such as pollination dependency were found to affect the plant response to variations in resource and pollen availability. Soil properties and crop pests might affect contribution of pollination to yield by altering the amount of resources a plant can allocate to reproduction, independently of the amount of pollen provided. Current management strategies to enhance pollinators might fail to increase pollination benefits in landscapes characterized by poor soil resources or ineffective pest control. We propose that our understanding of the effects of crop-pollinator interactions will benefit by focusing on plant traits and physiological responses. Combining knowledge from plant physiology and ecology with technological advances in agriculture is needed to design novel management strategies to maximize pollination benefits and support yields and reduce environmental impacts of food production. [ABSTRACT FROM AUTHOR]

Highlights • We compared the performance of biodiversity metrics on pond macrophyte patterns. • We found complementarity between functional, beta and phylogenetic diversity. • These three metrics provide a complete picture of macrophyte diversity patterns. • Our work underlines the importance of considering several metrics of biodiversity. Abstract Ecological metrics constitute one of the mainstream tools in modern ecology to assess varying information about processes and patterns of regional biodiversity. However, the performance of different metrics on Mediterranean pond macrophyte assemblages is still largely unknown, thus hampering the selection of suitable indices for biomonitoring purposes. In an attempt to fill this gap of knowledge, we compared the response of six ecological metrics (i.e. species richness, Shannon diversity, beta diversity, functional diversity, and average and variation in taxonomic distinctness) to determine which ones are redundant and constructed Generalized Additive Models (GAM) to assess their utility for macrophyte biodiversity evaluation. The study was performed at assemblage level in a vast area of approximately 94,000 km2 in northwestern Spain. Several environmental filters related to habitat conditions revealed themselves to have considerable impact on biodiversity measures. Physical factors exhibited the highest drop in deviance values for species richness, Shannon diversity and functional diversity, whereas beta diversity and taxonomic distinctness metrics were more sensitive to water chemistry changes. Our results, based on correlations among indices and partial response curves to primary environmental drivers, showed complementarity in at least three different biodiversity measures (i.e. functional diversity, beta diversity and taxonomic distinctness). Ultimately, the use of a combination of these three metrics should provide a complete picture of macrophyte biodiversity patterns and their response to major environmental forces, including the variation in the identities of species among communities and the functional and phylogenetic status of species. These findings underline the importance of considering different biodiversity measures for conservation planning at regional scale and should assist in the selection of suitable indices for future pond management initiatives in Mediterranean landscapes. [ABSTRACT FROM AUTHOR]

Abstract Environmental stressors and population growth have significantly affected terraced rice ecosystems, such as in the Sapa district in northern Vietnam. The question arises how natural and socio-economic components determine the amount of rice yields. This study combines a hybrid neural-fuzzy inference system (HyFIS) with GIS-based methods to generate two models that can map suitability areas for rice cultivation at a regional scale and predict actual rice yields at a plot scale. Semi-structured interviews, the "Integrated Valuation of Ecosystem Services and Tradeoffs" tool and different statistical models were used to investigate the impacts of eight environmental variables and three socio-economic variables on rice production. Subsequently, two HyFIS models were trained with an accuracy higher than 88%. Because the predictive power values of the two proposed HyFIS models were higher than those of benchmark models, they are considered as useful tools to assess and optimize land use and related rice productivity. Highlights • Hybrid models integrating neural network, fuzzy logic and geographical information system approaches were developed to find areas suitable for rice cultivation (a so-called S-HyFIS model) and to predict rice yields (a so-called I-HyFIS model). • Impacts of environmental characteristics and additional human inputs on rice production were quantified. • The S-HyFIS model can extrapolate results from plot to regional scales in order to generate a map representing crop suitability areas for rice cultivation. • The potential of conversion from different land uses/covers to arable lands and vice versa were analyzed in the Sapa district, Lao Cai province, Vietnam. [ABSTRACT FROM AUTHOR]

Ecological niche shifts between diploid and tetraploid plants remains a topic with potential for plant ecology and evolution. Here, we identified populations of Fragaria (Rosaceae) from 169 sampling plots, classifying populations into two species groups (diploid and tetraploid) across China using flow cytometry. We then applied niche modeling to assess the ecological niche shift between diploid and tetraploid plants of Fragaria in China based on fieldwork and herbarium data. We explored the variables that best explained niche shifts between diploid and tetraploid plants. Compared to diploid plants, tetraploid plants are more likely to inhabit areas of higher altitude, lower temperature and lower precipitation, indicating that different ploidy levels are mainly associated with niche changes of altitude, temperature and precipitation. Diploid and tetraploid plants of Fragaria exhibit significant niche shifts (i.e. niche divergence between types). Ecological niche divergence between diploid and tetraploid plants is best explained by a shift in climate and altitude in biomes of conifer forests of southwestern China. Moreover, heterogeneity of soil further contributed to the observed niche shift between diploid and tetraploid plants. Our study provides novel insights into the role of niche shifts on genome mergers and duplications of Fragaria in China. • We used niche modeling to assess the ecological niche shift between diploid and tetraploid plants of Fragaria in China. • Ecological niche Shift is best explained by a change of climate and altitude in conifer forests of southwestern China. • Our study provides novel insights into the role of niche shift on genome merger and duplication for Fragaria plants. [ABSTRACT FROM AUTHOR]

Highlights • The orientation of the inner-nest ants delineates the entrance area of the nest. • Ants facing the nest entrance receive the majority of contacts with returning ants. • These ants act as a social interface between the nest and the environment. • The size of this social interface increases with the number of open entrances. • Flows of foragers increase and homogeneously spread between newly open entrances. Abstract Nest entrances are key locations where information about environmental opportunities and constraints are shared between foragers and inner-nest workers. However, despite its functional value, we still lack a detailed characterisation of the interface between the nest and the environment. Here, we identified the social interface in the ant Myrmica rubra as being the population of ants that faced the nest entrance and that received significantly more contacts from returning foragers than other nearby ants. We also spatially delineated the entrance area that hosted the social interface, a 2-centimetre radius area from the nest openings, which influences the position, orientation, and behaviour of ants. Then, we studied the impact of additional entrances on this social interface as well as on the flow of foragers. The size of the social interface increased according to the number of open entrances through the progressive reorientation of the ants toward new openings. We also observed a significant, although less than proportional, increase in the flows of ants that were progressively distributed homogeneously between all open entrances. Thus, our work highlights the flexibility of both the social interface and the flow of foragers to changes in the numbers of passageways between the nest and the environment. [ABSTRACT FROM AUTHOR]

Highlights • Six-year-old Scots pine post-harvest stand was a modest carbon source. • Eddy covariance and C budgeting methods yielded similar results for the annual C balance. • Studied ecosystem will be able to turn into a C sink already before ten years after cutting. • Understorey vegetation contributed 57% to annual net primary production in studied stand. Abstract Clear-cutting is a conventional method of forest management which significantly changes carbon (C) cycling at the ecosystem level for a long time. Estimation of the interim period during which the ecosystem turns from a C source to a C sink is crucial for clarifying the environmental effects of management on forest C cycling. The current study provided new knowledge of C cycling in young pine stand and demonstrated the recovery of C sequestration of the forest ecosystem during the post harvesting period. We estimated the C balance in a 6-year-old Scots pine stand by using two different methods: carbon budgeting, for estimating annual net ecosystem production (NEP), and eddy covariance (EC), for estimating net ecosystem exchange (NEE). For C budgeting, the above- and belowground biomass production of the ecosystem, as well as the soil heterotrophic respiration efflux at the studied site was estimated. Annual NEE at the studied young forest ecosystem was 1.19 ± 0.36 t C ha−1, gross primary ecosystem production was 9.87 and total ecosystem respiration was 11.06 t C ha−1. Estimated NEE was in good accordance with the results of NEP (1.37 t C ha−1), which confirms the relevance of the C budgeting method. Increased annual woody biomass production is the main factor which induced the young Scots pine ecosystem to act as a C sink: annual C accumulation in tree biomass in a 6-year-old stand was 1.0 t C ha−1 but reached already 2.4 t C ha−1 in the following year. Assuming that the annual R h flux is of the same magnitude in the subsequent years, the ecosystem will become a C sink already during a short period after clear-cut. Annual soil respiration (R s) and heterotrophic soil respiration (R h) were 6.0 and 4.2 t C ha−1, respectively and the R h /R s ratio was 0.70. However, at this stage also the understorey vegetation contributed essentially to NEP, making up 56% of the annual C uptake accumulated in the plants. The methane flux and the leached C flux were negligible, 0.004 and 0.015 t C ha−1 yr−1, respectively. Our results demonstrate that well regenerated young Scots pine stand on a former clear-cut area will be able to turn into a C sequestering ecosystem already before ten years after cutting. [ABSTRACT FROM AUTHOR]

Highlights • We evaluate if Eucalyptus plantations are novel or hybrid ecosystems. • We compare biotic and abiotic components among the ecosystems evaluated. • Eucalyptus plantations are hybrid ecosystems. • Proper management of this system might improve its conservation value. • Modified ecosystems present different potential for biodiversity conservation. Abstract Novel and hybrid ecosystems present different conservation values for native species. Therefore, the classification of modified ecosystems into a novel or hybrid state is an essential step to assist conservation strategies for biodiversity. During the last decades, plantations of Eucalyptus have increased in the highly threatened Atlantic Forest region, highlighting the importance of defining this ecosystem as novel or hybrid. In this study, we evaluated whether Eucalyptus plantations are novel or hybrid ecosystems by contrasting biotic components (dung beetle communities) and abiotic components (local environmental variables) within historical (Atlantic Forest remnants) and non-historical (pasture) environments in the Atlantic Forest biome, located in Bahia state, Brazil. Our results show that Eucalyptus plantations should be classified and managed as a hybrid ecosystem in this biome. Of the 21 dung beetle species found in Eucalyptus , ten were shared with historical forests (52.6% of Eucalyptus species) and 6 with pastures (31.5%). Eucalyptus plantations have environmental aspects similar to both historical forests and pastures. Despite presenting similar components to historical and non-historical ecosystems, Eucalyptus plantations are sufficiently distinct not to be classified as either one of them. Our results highlight the potential conservation value of Eucalyptus plantations in the Atlantic Forest region as complementary habitat for historical species, and we discuss how alternative management at landscape and stand (local) scales might increase this value. Although dung beetles are an excellent group to monitor biodiversity, we reinforce the necessity to perform further studies using another taxon that present different ecosystem requirements. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A very special and endemic flora develops on gypsiferous soils worldwide. • The close link between flora and gypsum soils is called gypsophily. • The ability of plants to accumulate Ca, Mg and S is used to explain gypsophily. • Objective thresholds have never been defined to establish a plant as an accumulator. • Proposed thresholds: 6.6 % dry weight for Ca; 1.4 % for Mg; and 1.9 % for S. Abstract Plants that show a strict link with gypsum soils, gypsophytes, constitute a major current research topic in the field of plant ecology. Among the hypotheses proposed to explain this close relationship, the nutritional imbalances that this type of soil implies for plants stands out. According to this hypothesis, gypsophytes would be able to accumulate high contents of certain key minerals such as Ca, Mg and S, especially in leaves. Although the distinction between gypsophile and non-gypsophile species has often been based on the capacity to accumulate the aforementioned mineral elements, objective thresholds have never been established. The main aim of the present work is to establish the levels of Ca, Mg and S above which a species can be considered an accumulator of these elements. To this end, the concentration ranges included in handbooks and papers on plant nutrition with information for a large number of species were used as a starting point. Based on these ranges, thresholds for four Nutritional Content Levels (NCL) for Ca, Mg and S were established: deficient, normal, high and very high. For each level, a numerical value between 1 and 4 was assigned, from lowest to highest. The sum of the values of the levels of accumulation (Additional Nutritional Value, ANV) corresponding to the three elements mentioned served to classify the species studied in groups or categories (N_STRATEGY). These categories were adjusted to the classic strategies that divide the plants into exclusors (values between 3 and 5), indicators (6–9) and accumulators (10–12). The N_STRATEGY predictive power of plants' gypsophily degree was statistically analysed (Artificial Neural Networks). The categories established by N_STRATEGY showed a high predictive value (up to 98%) to detect gypsophily in plants and proved a more objective and easier criterion than previous functional classifications proposed for gypsophytes. It has an additional advantage in that it can also be applied to other plants linked with special substrates (serpentines, dolomites, etc.). The results regarding the nutritional contents of Ca, Mg and S showed that Ononis tridentata and the Gypsophila genus, both taxa with succulent leaves, are accumulators for all these elements. Ca seems clearly associated with the succulent character of the leaves. Another novel contribution is the role in the interpretation of the gypsophile flora played by Mg, whose importance is likely greater than has been considered to date. This research confirms previous results on S and pinpoints it as the element that best discriminates between gypsophytes and non-gypsophytes or gypsovags. [ABSTRACT FROM AUTHOR]

Highlights • Floating clonal plants are susceptible to fragmentation in aquatic ecosystems. • At low nutrients, competition affected smaller fragments of Salvinia natans more. • Eutrophication could alleviate low competitive ability of small clonal fragments. • Competition had less effect on S. natans at low than at high nutrient availability. Abstract Groups of connected ramets produced by clonal growth in plants are particularly susceptible to fragmentation in aquatic ecosystems. Both clonal fragment size and nutrient availability are likely to affect the competitive ability of clonal aquatic plants, but the effects of fragment size, nutrients, and competition on plant performance have rarely been studied in combination. We hypothesized that larger fragments have greater competitive ability and that this effect is greater when nutrients are lower. To test this and other interactive effects, we grew fragments of the widespread, floating, clonal pteridophyte Salvinia natans initially containing 1, 2, 3, or 6 ramets at two levels of nutrients with and without a co-occurring, floating pteridophyte, Azolla pinnata, for 7 weeks. Floating mass of S. natans was mostly higher and submerged mass lower at high than at low nutrients, summing to a 0–30 % increase in total mass with higher nutrients at different initial fragment sizes. The presence of A. pinnata reduced total mass of S. natans by 30–60%. In partial agreement with the hypotheses, response of S. natans to competition was less negative in larger fragments in the low nutrient treatment but did not vary consistently with initial fragment size in the high nutrient treatment. Results show that growth of aquatic clonal plants can be determined by complex interactions and suggest that eutrophication may increase the competitive ability of very small clonal fragments. [ABSTRACT FROM AUTHOR]

Abstract With 450,000 km2 Kobresia (syn. Carex) pygmaea dominated pastures in the eastern Tibetan highlands are the world's largest pastoral alpine ecosystem forming a durable turf cover at 3000–6000 m a.s.l. Kobresia 's resilience and competitiveness is based on dwarf habit, predominantly below-ground allocation of photo assimilates, mixture of seed production and clonal growth, and high genetic diversity. Kobresia growth is co-limited by livestock-mediated nutrient withdrawal and, in the drier parts of the plateau, low rainfall during the short and cold growing season. Overstocking has caused pasture degradation and soil deterioration over most parts of the Tibetan highlands and is the basis for this man-made ecosystem. Natural autocyclic processes of turf destruction and soil erosion are initiated through polygonal turf cover cracking, and accelerated by soil-dwelling endemic small mammals in the absence of predators. The major consequences of vegetation cover deterioration include the release of large amounts of C, earlier diurnal formation of clouds, and decreased surface temperatures. These effects decrease the recovery potential of Kobresia pastures and make them more vulnerable to anthropogenic pressure and climate change. Traditional migratory rangeland management was sustainable over millennia, and possibly still offers the best strategy to conserve and possibly increase C stocks in the Kobresia turf. Graphical abstract Unlabelled Image Highlights • Kobresia pygmaea is co-limited by low rainfall, short growing season and livestock. • Overstocking has caused pasture degradation and soil deterioration. • Natural autocyclic processes of turf erosion are initiated by polygonal cracking. • C & nutrient release, earlier diurnal cloud formation, surface temperature decrease. • Traditional migratory rangeland management offers best strategy for conservation. [ABSTRACT FROM AUTHOR]

Highlights • Cotton seed costs are considerable, though planting at high rates is common. • Similar yield responses to plant density were observed across diverse environments. • Decreases in lint yield generally occur only at very low population densities. • A plant density threshold to maximize yield was identified at 35,000 plants ha-1. • This threshold can be used to better optimize seeding rate and assess replant need. Abstract Technology fees associated with modern cotton cultivars have increased seed costs considerably, giving producers the impetus to reduce plant population density, where possible. Most recent studies on cotton population density, conducted across diverse environments, report similar patterns of crop response: decreases in lint yield only at very low densities, with generally consistent yield across all higher densities. But no work had been done to bring the literature together, quantitively synthesizing the yield data collectively, to better pinpoint a population density threshold. And, notably, little had been reported on the effects of population density in lower-yielding dryland environments. Quantitatively synthesizing population density datasets from the literature, including our own dryland data, was the objective of this research. The dryland data showed that lint yield and biomass partitioning were not affected by population density, similar to higher-yielding environments over the same range in density. Following normalization of all lint yield data (literature and dryland datasets), a breakpoint in population density at 35,000 plants ha−1 was identified, which can be interpreted as the minimum plant density at which yield may be optimized. This rate is lower than the common density recommendation of 81,000 plants ha−1 and substantially lower than the risk-averse rates at which many producers plant (129,000 seeds ha−1 or greater). The analysis showed that yield will decline precipitously below 35,000 plants ha−1, exposing the enormous risk to cotton producers in approaching this low density, particularly if significant seed or plant loss is expected. However, the analysis suggests that excessive over-seeding may be occurring in many cases, resulting in economic losses to producers. The analysis also provides guidance on a threshold for producers facing replanting decisions. [ABSTRACT FROM AUTHOR]

Abstract Rare earth elements (REEs) have recently received particular attention due to their accumulation in the environment. Such heightened recognition prompted our evaluation of the possible occurrence of La-induced plant hormesis in the peer-reviewed literature. This study revealed 703 La-induced hormetic concentration/dose responses in plants, which were quantitatively and qualitatively assessed. The maximum (MAX) biological response to low La concentrations/doses is commonly below 150% of control response, with a geometric mean of 142% at 56 μM (geometric mean). The geometric mean concentration of the no-observed-adverse-effect-level (NOAEL) was 249 μM. The MAX:NOAEL distance was commonly below 5-fold, with a geometric mean of 4.5-fold. Hormetic concentration/dose responses varied as per the growth substrate pH, number of concentrations/doses below the NOAEL, and time window. These results provide a unique insight into the effects of low doses of La on plant growth, as well as offer means for improving experimental designs to assess low dose effects. Graphical abstract Image 1 Highlights • We assessed 703 hormetic-like lanthanum-induced dose responses in plants. • The maximum (MAX) stimulatory response was commonly <150% of control response. • The MAX to no-observed-adverse-effect-level (NOAEL) distance was commonly <5 fold. • The number of doses below the NOAEL was found to affect hormesis' properties. • Growth substrate pH and time windows were also found to affect hormesis' features. Lanthanum-induced hormetic dose-responses commonly show a maximum response <150% of control response and have a MAX:NOAEL distance <5 fold. [ABSTRACT FROM AUTHOR]