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Cliffs contain one of the least known plant communities, which has been overlooked in biodiversity assessments due to the inherent inaccessibility. Our study adopted the unmanned aerial vehicle (UAV) with the telephoto camera to remotely clarify floristic variability across unreachable cliffs. Studied cliffs comprised 17 coastal and 13 inland cliffs in Gageodo of South Korea, among which 9 and 5 cliffs were grazed by the introduced cliff-dwelling goats. The UAV telephotography showed 154 and 166 plant species from coastal and inland cliffs, respectively. Inland cliffs contained more vascular plant species (P < 0.001), increased proportions of fern and woody species (P < 0.05), and decreased proportion of herbaceous species (P < 0.001) than coastal cliffs. It was also found that coastal and inland cliffs differed in the species composition (P < 0.001) rather than taxonomic beta diversity (P = 0.29). Furthermore, grazed coastal cliffs featured the elevated proportions of alien and annual herb species than ungrazed coastal cliffs (P < 0.05). This suggests that coastal cliffs might not be totally immune to grazing if the introduced herbivores are able to access cliff microhabitats; therefore, such anthropogenic introduction of cliff-dwelling herbivores should be excluded to conserve the native cliff plant communities. [ABSTRACT FROM AUTHOR]

Understanding what makes a community vulnerable to invasion is integral to the successful management of invasive species. Our understanding of how characteristics of resident plant interactions, such as the network architecture of interactions, can affect the invasibility of plant communities is limited. Using a simulation model, we tested how successfully a new plant invader established in communities with different network architectures of species interactions. We also investigated whether species interaction networks lead to relationships between invasibility and other community properties also affected by species interaction networks, such as diversity, species dominance, compositional stability and the productivity of the resident community. We found that higher invasibility strongly related with a lower productivity of the resident community. Plant interaction networks influenced diversity and invasibility in ways that led to complex but clear relationships between the two. Heterospecific interactions that increased diversity tended to decrease invasibility. Negative conspecific interactions always increased diversity and invasibility, but increased invasibility more when they increased diversity less. This study provides new theoretical insights into the effects of plant interaction networks on community invasibility and relationships between diversity and invasibility. Combined with increasing empirical evidence, these insights could have useful implications for the management of invasive plant species. [ABSTRACT FROM AUTHOR]

More than 20 years after remedial measures were carried out, six plots (Š1 – Š6) at the Šobov locality were examined in more detail. From a pedological viewpoint, the physico-chemical differences of the soils in these areas are not the result of pedogenesis. This is the effect of extremely acidic mineralised solutions that have leaked from or are still leaking from the heap at the site. The plant community here is most often poor to weakly developed with acidophilic vegetation (Š1, Š2, Š5), without vegetation (Š4) or with dense species-rich vegetation (Š3, Š6). Saprotrophic microscopic fungi of the phylum Zygomycota are notably suppressed and their diversity is low. Species of the genera Absidia and Zygorhynchus were found most often. In contrast, the diversity of the phylum Ascomycota is notably high. The genera Penicillium (35 species), Aspergillus (7 species) and Trichoderma (5 species) are dominantly represented. Species of microscopic filamentous fungi in every soil sample that did not occur in the other samples were also recorded; i.e. they form the specific soil mycobiome of the given location. From the 15 types of keratinophilic fungi, the most commonly occurring were Purpureocillium lilacinum and Keithomyces carneus. Keratinolytic properties were recorded only in the species Trichophyton ajelloi. Soil reaction is the most important ecological factor that influences the biological properties of soils. [ABSTRACT FROM AUTHOR]

Background and aims: In mature forests, tree and shrub mycorrhizal associations integrate plant and fungal functional traits, making these relationships important controls on soil nitrogen availability. Whether these plant-fungal effects are observed in forests during early succession following disturbances is largely unexplored. We quantify differences in soil nitrogen availability under an ectomycorrhizal tree (Betula lenta) and an ericoid mycorrhizal shrub (Kalmia latifolia) and explore the potential for known mechanisms, such as the availability of soil carbon, to explain the patterns observed. Methods: We analyze variables indicative of soil nitrogen and carbon availability for incubated soil samples collected from under ecto- or ericoid mycorrhizal plants within a recently harvested temperate forest. Specific measures include net nitrogen mineralization, nitrification, and carbon mineralization rates; active microbial biomass; particulate and mineral-associated soil organic carbon and nitrogen concentrations; and carbon and nitrogen concentrations in plant tissues. Results: Net nitrogen mineralization and nitrification rates were lower under ericoid shrubs than ectomycorrhizal trees. Soil carbon availabilities were similar, suggesting that mechanisms other than carbon accumulation likely create nitrogen limitation under the ericoid shrub in early successional forests. Ectomycorrhizal plant tissues also had higher nitrogen contents and lower carbon-to-nitrogen ratios than ericoid shrubs, providing further support for greater soil nitrogen limitation in the ericoid plots. Conclusion: Our findings suggest local heterogeneity of plant mycorrhizal associations, or at least plant functional types, will be important for understanding differences in soil nitrogen availability in early versus mid- to late-successional forests and hence forest ecosystem responses to intensifying disturbance regimes. [ABSTRACT FROM AUTHOR]

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

The yield and production of several crops, including wheat (Triticum aestivum L.), which is the most significant crop in the world, have been significantly affected by drought occurrences in various parts of the world. By Using the randomized complete block design, which is based on three replications, a set of 100 wheat accessions were examined under normal and drought stress condition. The analysis of variance revealed that the genotypes significantly varied in all of the qualities in both condition under normal and drought stress, which demonstrating the wide range of genotypes that can be used in breeding strategies for improvement. The study revealed significant differences among genotypes under both normal and drought conditions, highlighting the varying responses to stress. According to the results of the correlation study, in normal conditions, the grain yield per plant exhibits a significant and favorable link with every trait that was studied. Under drought conditions, grain yield per plant has a negative association with plant height, which has an impact on grain production and results in a significant decrease in the wheat crop's output. The genotypes G27, G28, G71, G72, and G89 performed best under drought conditions and were termed drought resistant genotypes, according to the mean variability, whereas the genotypes G50, G53, G54, G80, and G88 performed poorly and were considered as drought sensitive. Highest broad-sense heritability (84–96%) and genetic advance exceeded 20% that emphasized the role of genetic factors in influencing studied traits which exhibited significant potential for improvement through selective breeding, particularly in drought-stress. Results obtained from principal component analysis, only 4 PCs showed the significant variability due to having eigenvalues > 1. These 4 PCs cumulatively accounted for 66.1% and 63.8% of the total variability under normal and drought conditions. Eigenvalues, proportions, and cumulative values of principal components were analyzed, indicating that the first few principal components captured the majority of the variance in the dataset. Loading factor analysis further revealed the correlation between original variables and principal components, aiding in understanding the contribution of each trait to overall variance. The identification of drought-tolerant genotypes and the delineation of trait relationships provide crucial information for future breeding endeavors, aiming at enhancing wheat resilience and ensuring sustainable wheat production in the face of environmental challenges. This study will also enhance the understanding of genetic basis of wheat traits and their responses to drought stress. [ABSTRACT FROM AUTHOR]

Plant diversity can significantly affect the grassland productivity and its stability. However, it remains unclear how plant diversity affects the spatial stability of natural grassland productivity, especially in alpine regions that are sensitive to climate change. We analyzed the interaction between plant (species richness and productivity, etc.) and climatic factors (precipitation, temperature, and moisture index, etc.) of alpine natural grassland on the Qinghai-Tibetan Plateau. In addition, we tested the relationship between plant diversity and spatial stability of grassland productivity. Results showed that an increase in plant diversity significantly enhanced community productivity and its standard deviation, while reducing the coefficient of variation in productivity. The influence of plant diversity on productivity and the reciprocal of productivity variability coefficient was not affected by vegetation types. The absolute values of the regression slopes between climate factors and productivity in alpine meadow communities with higher plant diversity were smaller than those in alpine meadow communities with lower plant diversity. In other words, alpine meadow communities with higher plant diversity exhibited a weaker response to climatic factors in terms of productivity, whereas those with lower plant diversity showed a stronger response. Our results indicate that high plant diversity buffers the impact of ambient pressure (e.g., precipitation, temperature) on alpine meadow productivity, and significantly enhanced the spatial stability of grassland productivity. This finding provides a theoretical basis for maintaining the stability of grassland ecosystems and scientifically managing alpine grasslands under the continuous climate change. [ABSTRACT FROM AUTHOR]

Backgrounds: Climate change is well-known to alter the structure and function of grassland ecosystems, and multifunctionality contributes to a comprehensive understanding of the impacts of climate change on ecosystem functions. Warming and humidification are predicted to be the climate change trend on the northeastern Qinghai-Tibetan Plateau. However, understanding of how long-term warming and increased precipitation affect ecosystem multifunctionality in alpine meadows is still limited. Methods: Here, we conducted an 8-year field experiment involving warming and increased precipitation in an alpine meadow to explore how warming, increased precipitation, and their interaction affect ecosystem multifunctionality. Results: The results indicated that increased precipitation had a positive effect on ecosystem multifunctionality. However, warming and the interaction of warming and precipitation had no significant effects on it. Warming decreased species richness and plant coverage. Increased precipitation enhanced aboveground carbon (C), nitrogen (N), and phosphorus (P) pools of plant community, and soil moisture, but decreased soil pH. Aboveground P and N pools of plant community and microbial biomass nitrogen (MBN) were important predictors of ecosystem multifunctionality. Conclusion: This study demonstrated long-term increased precipitation can enhance ecosystem multifunctionality by indirectly affecting the individual functions (aboveground P and N pools of plant community and MBN), soil moisture, and pH in an alpine meadow. These findings highlighted that increased precipitation is more critical than warming for enhancing ecosystem multifunctionality in semi-arid alpine meadows. [ABSTRACT FROM AUTHOR]

Aims: Plant functional group (PFG) removal experiments are recognized as an effective way to explore the role of plant diversity and species traits in ecosystem functioning. To minimize soil physical disturbance in plant removal experiments, aboveground parts of targeted plant species are usually cut off without removing their roots from the soil. However, the potential effects of their remaining roots (partially as root litter) on soil nematode communities are still unclear. Methods: We used a three-year PFG removal experiment in a Qinghai-Tibet alpine meadow and set up root-ingrowth mesh bags for one year where removal target plants' roots existed only outside the mesh bags. Results: We found that nematode communities outside the mesh bags had higher nematode channel ratio and lower channel index values, indicating that the root litter outside the mesh bags increased energy flux to bacterial-feeding nematodes over fungal-feeding nematodes. The relative abundance of plant-feeding nematodes was higher inside than outside the mesh bags, probably because of a higher ratio of living roots inside the mesh bags. Non-metric multidimensional scaling showed that the structure of nematode communities inside and outside of mesh bags was generally differentiated except for the no-removal control treatment. Conclusions: We conclude that the remaining roots outside mesh bags could modify the relative abundance ratio of different nematode guilds and soil nematode community structures, suggesting legacy effects of target plants' roots in PFG removal experiments. [ABSTRACT FROM AUTHOR]

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

The plant microbes are an integral part of the host and play fundamental roles in plant growth and health. There is evidence indicating that plants have the ability to attract beneficial microorganisms through their roots in order to defend against pathogens. However, the mechanisms of plant microbial community assembly from below- to aboveground compartments under pathogen infection remain unclear. In this study, we investigated the bacterial and fungal communities in bulk soil, rhizosphere soil, root, stem, and leaf of both healthy and infected (Potato virus Y disease, PVY) plants. The results indicated that bacterial and fungal communities showed different recruitment strategies in plant organs. The number and abundance of shared bacterial ASVs between bulk and rhizosphere soils decreased with ascending migration from below- to aboveground compartments, while the number and abundance of fungal ASVs showed no obvious changes. Field type, plant compartments, and PVY infection all affected the diversity and structures of microbial community, with stronger effects observed in the bacterial community than the fungal community. Furthermore, PVY infection, rhizosphere soil pH, and water content (WC) contributed more to the assembly of the bacterial community than the fungal community. The analysis of microbial networks revealed that the bacterial communities were more sensitive to PVY infection than the fungal communities, as evidenced by the lower network stability of the bacterial community, which was characterized by a higher proportion of positive edges. PVY infection further increased the bacterial network stability and decreased the fungal network stability. These findings advance our understanding of how microbes respond to pathogen infections and provide a rationale and theoretical basis for biocontrol technology in promoting sustainable agriculture. Key points: • Different recruitment strategies between plant bacterial and fungal communities. • Bacterial community was more sensitive to PVY infection than fungal community. • pH and WC drove the microbial community assembly under PVY infection. [ABSTRACT FROM AUTHOR]

Determining the structure and fuel load is key to know the flammability of vegetation in the Mediterranean Basin where forest fires are frequent. Determine which plant structural variable is best related to living and dead fuel to develop allometric equations in nine species in the Western Mediterranean Basin. In the east of the Iberian Peninsula (Valencia Province), we measured four structural variables (basal stem diameter, height, maximum diameter and perpendicular diameter) that were related, by means of allometric equations, to the living and dead fuel separated into different size classes. We also analyze fuel changes across developmental states of the studied species, and the vertical distribution of dead fuel. General equations that consider all development states can be used to determine living fuel. However to obtain dead fuel, we recommend using specific equations for each development state and fuel fraction for better accuracy. The basal stem diameter was the best structural variable in almost all cases for estimating fuel in the studied species. Dead fuel load throughout species' ontological development is a key factor to manage Mediterranean plant communities. [ABSTRACT FROM AUTHOR]

Differences between peak-season and off-season dry mass, organic matter mass, and both concentrations and pools (standing stocks) of ash, N, P, K, Ca, Mg and Na were investigated in the rhizosphere soil, and live and dead aboveground plant biomass at 14 sites hosting 4 plant community types in the littoral zone of a eutrophic ancient shallow reservoir of about 5 km2 area, the Rožmberk fishpond (S. Bohemia, CZ). Comparisons between the peak-season and off-season data and several stoichiometric relations calculated from them provided an insight into the mineral nutrient economy of the examined types of the fishpond littoral vegetation. It is rooted in relatively nutrient-poor sandy soil, but differently enriched with nutrients contained in either the percolating fishpond water, or that of springs located at the landward edge of the littoral zone. The degree of eutrophication of our sampling sites and their vegetation thus seem to be positively correlated with the degree of contact of the plants´ rhizosphere with the nutrient-richer fishpond or spring water. [ABSTRACT FROM AUTHOR]

High-latitude warming is increasing soil temperatures and driving permafrost thaw, potentially altering soil nutrient conditions by enhancing microbial mineralization and making nutrients from previously frozen soils accessible for plant and microbial use. Increases in soil nutrient concentrations may alter plant community processes and, consequently, carbon (C) fluxes. We conducted an experiment in a boreal permafrost peatland, monitoring forest floor C flux and functional traits of the entire moss and vascular plant communities to the addition of nutrients at 20 and 40 cm soil depths and under closed and open canopy conditions. Plant functional trait responses were investigated at both community level (using community-weighted means) and intraspecific scales. Using fertilizer additions, we emulated nutrient increases at different depths in the soil profile, replicated at high and low canopy cover sites to assess the influence of light availability. Our results demonstrate rapid responses of vascular plant community-level traits as well as ecosystem respiration and gross primary productivity to fertilization treatments under low canopy cover, suggesting an influence of local environmental variation. We found that moss community-level traits played a more important role in mediating C flux response to nutrient fertilization than vascular plants but led to little change in C sink–source dynamics. This provides insight into existing ambiguities of the response of boreal C fluxes to increased nutrient availability following soil warming and permafrost thaw: Local environmental conditions and moss community can strongly mediate the response, whereas vascular plant communities may play a more minor role. However, our results suggest that these changes may not alter overall C sink–source dynamics of peatlands in the near term. [ABSTRACT FROM AUTHOR]

Traditionally, calcareous beech forests were classified and differentiated according to vascular plants. Bryophytes were often omitted or not all substrates were sampled in relevés, and therefore, the role of bryophytes in plant community differentiation remained unclear. In this paper, we studied bryophyte species richness, composition and functional patterns in vegetation units differentiated by vascular plants. We analysed 45 phytosociological relevés from 400 m2 plots in Fagus sylvatica-dominated forests on dolomite bedrock in Central Slovakia. The most frequent among 59 moss and 8 liverwort species was Tortella tortuosa, followed by Hypnum cupressiforme, Brachytheciastrum velutinum and Ctenidium molluscum. Average richness of bryophytes was 8.1 compared to 38.7 species of vascular plants. Seven bryophyte species were significantly linked to a particular vegetation unit. One-way ANOVA showed no noticeable differences in bryophyte species richness between vegetation units. However, it was negatively affected by xericity and positively by cover of rocks on soil surface. CCA revealed that species composition was affected significantly by xericity, cover of bare rocks and cover of tree layer. Mat and turf life forms prevailed, and both long-lived taxa/perennials and short-lived colonists formed the bryophyte layer. Observed bryophyte species grew mostly on rock, living and dead wood, and only minority of them on soil. Therefore, available substrates greatly contributed to the species richness of bryophytes and total plant diversity of the forest community. A complete investigation of substrates is necessary to assess the drivers of bryophyte species distribution and diversity, and their role in classification of calcareous beech forests. [ABSTRACT FROM AUTHOR]

Changing environment markedly shapes plant diversity and vegetation across all spatial scales. It leads to innumerable local, regional and sometimes global changes in plant communities. Here, we present eleven full-text research articles of the Special Issue "Plant communities in changing environment", which focuses on the evaluation of plant diversity and vegetation changes in different plant communities. We conclude that the results of all research studies show that plants, habitat and functional diversity are strongly conditioned in space and time by various factors, including climate, water regime, snow conditions, and human activities. These changes are also among most significant potential threats for plant diversity. [ABSTRACT FROM AUTHOR]

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

Changes in climate and grazing intensity influence plant-community compositions and their functional structure. Yet, little is known about their possible interactive effects when climate change mainly has consequences during the growing season and grazing occurs off growing season (dormant season grazing). We examined the contribution of trait plasticity to the immediate responses in the functional structure of plant community due to the interplay between these two temporally disjunct drivers. We conducted a field experiment in the northern Mongolian steppe, where climate was manipulated by open-top chambers (OTCs) for two growing seasons, increasing temperature and decreasing soil moisture (i.e., increased aridity), and grazing was excluded for one dormant season between these two growing seasons. We calculated the community-weighted mean (CWM) and the functional diversity (FD) of six leaf traits. Based on a variance partitioning approach, we evaluated how much of the responses in CWM and FD to OTCs and dormant season grazing occur through plasticity. The interactive effect of OTCs and the dormant season grazing were detected only after considering the role of trait plasticity. Overall, OTCs influenced the responses in CWM more than in FD, but the effects of OTCs were much less pronounced where dormant season grazing occurred. Thus, warming (together with decreased soil moisture) and the elimination of dormant season grazing could interact to impact the functional trait structure of plant communities through trait plasticity. Climate change effects should be considered in the context of altered land use, even if temporally disjunct. [ABSTRACT FROM AUTHOR]

Whole-plant hydraulics provide important information about responses to water limitation and can be used to understand how plant communities may change in a drier climate when measured on multiple species. Here, we measured above- and belowground hydraulic traits in Cornus drummondii, an encroaching shrub within North American tallgrass prairies, and Andropogon gerardii, a dominant C4 grass, to assess the potential hydraulic responses to future drought as this region undergoes woody expansion. Shelters that reduced precipitation by 50% and 0% were built over shrubs and grasses growing in sites that are burned at 1-year and 4-year frequencies. We then measured aboveground (Kshoot), belowground (Kroot), and whole-plant maximum hydraulic conductance (Kplant) in C. drummondii and Kroot in A. gerardii. We also measured vulnerability to embolism (P50) in C. drummondii stems. Overall, we show that: (1) A. gerardii had substantially greater Kroot than C. drummondii; (2) belowground hydraulic functioning was linked with aboveground processes; (3) above- and belowground C. drummondii hydraulics were not negatively impacted by the rainfall reductions imposed here. These results suggest that a multi-year drought will not ameliorate rates of woody expansion and highlight key differences in aboveground and belowground hydraulics for dominant species within the same ecosystem. [ABSTRACT FROM AUTHOR]

Forest management relies on forest spatial structure, but studies on the spatial structure of Vietnamese forests are limited. Therefore, two one–hectare plots were established in tropical rainforest in Tuyen Quang province to evaluate the characteristics and spatial structures of plant communities. Descriptive statistics and species importance value indices were calculated for each plot. Then, to assess differences between plots, detrended correspondence analysis was applied. Species mingling, uniform angle, diameter dominance and carbon stock dominance indices were also computed to analyze forest spatial structures. The results indicated that 65–70% of trees occurred in areas with high diversity, and 55–58% of trees were randomly distributed. The number of dominant and non–dominant individuals, in terms of diameter and carbon stock, was similar at the stand level. In all estimated patterns, units with high species mixtures predominated. As biodiversity increased, the distribution of forest trees became more random. The quadrivariate distribution illustrated considerable differences between plots, the study area and other regions. Findings from multivariate distributions provide accurate information in each group of spatial indices and these can be used to select appropriate silvicultural measures for stand management. [ABSTRACT FROM AUTHOR]

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

Purpose: Simultaneous effects of more than one global change driver on ecosystem functioning have rarely been assessed. Methods: We disentangled the effects of region encompassing climatic and edaphic conditions, forest-management intensity and community plant diversity on litterfall quantity, quality and turnover in 27 temperate forests across an environmental gradient. Results: Region significantly influenced litterfall and organic layer mass and chemical quality and litter and element turnover. After accounting for the influence of region, increasing forest-management intensity (ForMI) significantly decreased litterfall mass, N, P and K concentrations and nutrient fluxes and slowed down litter and nutrient turnover. Because increasing ForMI reflected the man-made contributions of coniferous trees, these results can partly be attributed to the lower litterfall at our study sites and slower litter turnover of coniferous than deciduous trees. After accounting for the influences of region and ForMI, increasing diversity of the vascular plant community on the study plots measured as species richness or Shannon index significantly increased C and decreased N, P and S concentrations in litterfall. Together with the significantly decreased N and P concentrations in the organic layer with increasing plant diversity, these results indicated an increased within-stand nutrient-use efficiency and a more complete soil nutrient use with increasing plant diversity. Conclusions: Our results demonstrate that increasing ForMI, which is associated with increasing conifer shares, leaves element stocks in the organic layer unchanged but slows down C turnover and thus increases temporary C storage in soil organic layers. Moreover, community vascular plant diversity helps close nutrient cycles. [ABSTRACT FROM AUTHOR]

The structural characteristics of plant communities in urban green spaces have a significant impact on their carbon sequestration function. In this study, comprehensive data were collected from 106 plant communities (each 20 m × 20 m) in Zhengzhou Green Expo Park. We assessed aboveground and soil carbon storage, alongside maintenance carbon emissions, to quantify carbon dynamics. Our primary objective was to establish a statistical model that correlates the structural attributes of plant communities with their total annual carbon sequestration. This model aims to provide a quantitative framework for optimizing community structures to maximize carbon sequestration in urban green spaces. The results showed that density and coverage were significantly and positively correlated with aboveground and soil carbon stocks. Density and mean height were significantly and positively correlated with maintenance carbon emissions. Density played a key structural role in regulating the total carbon sequestration of the plant communities, being 27.24 times more effective than coverage. The total annual carbon sequestration of the plant community reached an optimal value of 327.67 kg CO2-eq/y−1 at a density and cover of 0.15 and 1, respectively. This study provides valuable data for increasing the carbon sink ability of urban green spaces through plant structure regulation and supporting low-carbon development strategies in urban management. [ABSTRACT FROM AUTHOR]

Research has demonstrated the positive effect of natural environment on human restoration and well-being. Time spent in nature can often alleviate both physiological and psychological stress. However, few studies have discussed the environmental health effects of the nature's components and characteristics. Sixty volunteers were recruited and one manufactured environment and five different natural environments were randomly assigned to them, including coniferous forests (pure coniferous forest-PC and mixed coniferous forest-MC), broad-leaved forests (pure broad-leaved forest-PB and mixed broad-leaved forest-MB), and mixed forest (mixed coniferous and broad-leaved forest-MCB). Each volunteer sat in a built or natural environment and looked around the environment for 15 min. Physiological (HR, HRV, BP, pulse rate and salivary cortisol) and psychological indicators (POMS and STAI) were used to evaluate the changes in their stress level. Results indicated a strong difference in HR, HRV, POMS and STAI between the built and natural environment, which showed that natural environment can lower the stress level. MC had the best effect on relieving physiological stress, whereas MCB is most successful in improving emotional state and reducing anxiety. Broad-leaved forest and mixed forest significantly affected the DBP and vigor level of the subjects, respectively. While coniferous forest did significantly increase the concentration of salivary cortisol in subjects. The study confirmed that compared to the built environment, the natural environment can relieve the human body's physical and psychological stress and negative emotions, while significantly increasing vitality. And different plant communities also have different effects on the physiological and psychological indicators of the subjects. These results will provide scientific basis for the construction and improvement of urban green space environment. [ABSTRACT FROM AUTHOR]

Plant community assembly is the outcome of long-term evolutionary events (evident as taxonomic diversity; TD) and immediate adaptive fitness (functional diversity; FD); a balance expected to shift in favour of FD in 'harsh' habitats under intense selection pressures. We compared TD and FD responses along climatic and edaphic gradients for communities of two species (Dianthus pseudocrinitus and D. polylepis) endemic to the montane steppes of the Khorassan-Kopet Dagh floristic province, NE Iran. 75 plots at 15 sites were used to relate TD and FD to environmental gradients. In general, greater TD was associated with variation in soil factors (potassium, lime, organic matter contents), whereas FD was constrained by aridity (drought adaptation). Crucially, even plant communities hosting different subspecies of D. polylepis responded differently to aridity: D. polylepis subsp. binaludensis communities included a variety of broadly stress-tolerant taxa with no clear environmental response, but TD of D. polylepis subsp. polylepis communities was directly related to precipitation, with consistently low FD reflecting a few highly specialized stress-tolerators. Integrating taxonomic and functional diversity metrics is essential to understand the communities hosting even extremely closely related taxa, which respond idiosyncratically to climate and soil gradients. [ABSTRACT FROM AUTHOR]

Relatively unmanaged interstitial areas at the residential–wildland interface can support the development of novel woody plant communities. Community assembly processes in urban areas involve interactions between spontaneous and cultivated species pools that include native, introduced (exotic/non-native) and invasive species. The potential of these communities to spread under changing climate conditions has implications for the future trajectories of forests within and beyond urban areas. We quantified woody vegetation (including trees and shrubs) in relatively unmanaged "interstitial" areas at the residential–wildland interface and in exurban reference natural areas in six metropolitan regions across the continental USA. In addition, we analyzed soil N and C cycling processes to ensure that there were no major anthropogenic differences between reference and interstitial sites such as compaction, profile disturbance or fertilization, and to explore effects of novel plant communities on soil processes. We observed marked differences in woody plant community composition between interstitial and reference sites in most metropolitan regions. These differences appeared to be driven by the expanded species pool in urban areas. There were no obvious anthropogenic effects on soils, enabling us to determine that compositional differences between interstitial and reference areas were associated with variation in soil N availability. Our observations of the formation of novel communities in interstitial spaces in six cities across a very broad range of climates, suggest that our results have relevance for how forests within and beyond urban areas are assessed and managed to provide ecosystem services and resilience that rely on native biodiversity. [ABSTRACT FROM AUTHOR]

Subarctic ecosystems are subjected to increasing nitrogen (N) enrichment and disturbances that induce particularly strong effects on plant communities when occurring in combination. There is little experimental evidence on the longevity of these effects. We applied N-fertilization (40 kg urea-N ha−1 year−1 for 4 years) and disturbance (removal of vegetation and organic soil layer on one occasion) in two plant communities in a subarctic forest-tundra ecotone in northern Finland. Within the first four years, N-fertilization and disturbance increased the share of deciduous dwarf shrubs and graminoids at the expense of evergreen dwarf shrubs. Individual treatments intensified the other's effect resulting in the strongest increase in graminoids under combined N-fertilization and disturbance. The re-analysis of the plant communities 15 years after cessation of N-fertilization showed an even higher share of graminoids. 18 years after disturbance, the total vascular plant abundance was still substantially lower and the share of graminoids higher. At the same point, the plant community composition was the same under disturbance as under combined N-fertilization and disturbance, indicating that multiple perturbations no longer reinforced the other's effect. Yet, complex interactions between N-fertilization and disturbance were still detected in the soil. We found higher organic N under disturbance and lower microbial N under combined N-fertilization and disturbance, which suggests a lower bioavailability of N sources for soil microorganisms. Our findings support that the effects of enhanced nutrients and disturbance on subarctic vegetation persist over decadal timescales. However, they also highlight the complexity of plant–soil interactions that drive subarctic ecosystem responses to multiple perturbations across varying timescales. [ABSTRACT FROM AUTHOR]

Many wetland plants rely on insects for pollination. However, studies examining pollinator communities in wetlands remain limited. Some studies conducted in large wetlands (> 10 ha) have suggested that wetland-dependent flies, which spend their larval stage in aquatic and semi-aquatic habitats, dominate as pollinators. However, smaller wetlands surrounded by secondary forests are more prevalent in Japan, in which pollinators from the surrounding environment might be important. Additionally, information regarding floral traits that attract specific pollinator groups in wetland communities is scarce. Therefore, this study aimed to understand the characteristics of insect pollinators in a small natural wetland (2.5 ha) in Japan. We examined the major pollinator groups visiting 34 plant species and explored the relationship between the flower visitation frequency of each pollinator group and floral traits. Overall, flies were the most dominant pollinators (42%), followed by bees and wasps (33%). Cluster analysis indicated that fly-dominated plants were the most abundant among 14 of the 34 target plant species. However, 85% of the hoverflies, the most abundant flies, and 82% of the bees were non-wetland-dependent species, suggesting that these terrestrial species likely originated from the surrounding environment. Therefore, pollinators from the surrounding environment would be important in small natural wetlands. Flies tend to visit open and white/yellow flowers, whereas bees tended to visit tube-shaped flowers, as in forest and grassland ecosystems. The dominance of flies in small wetlands would be due to the dominance of flowers preferred by flies (e.g., yellow/white flowers) rather than because of their larval habitats. [ABSTRACT FROM AUTHOR]

Background: The microbial community structure in forest soils is expected to change in response to global environmental change, such as climate warming and nitrogen deposition. Community responses to these environmental changes may further interact with the site's land-use history and understory light availability. Uncovering the relative importance of these global change drivers is crucial to understand and predict soil microbial communities' changes. Methods: A full-factorial in situ mesocosm experiment was conducted and the soil microbiota were analyzed by phospholipid fatty acid and neutral lipid fatty acid. The soils in the mesocosms were sampled from forests with different land-use history, and mesocosms contained typical forest understory plants. The mesocosms were exposed to experimental treatments of warming, nitrogen addition and subcanopy illumination. Results: Among the treatments, past land-use had the strongest effect shaping the microbial community structure. We found a significantly higher abundance of arbuscular mycorrhizal fungi and Actinobacteria in ancient forests. The soil microbial and plant communities were co-structured in ancient forests, but not in past-agricultural forests. Warming and nitrogen fertilization did not affect the soil microbial community composition, yet illumination resulted in slight changes in soil microbial composition. Conclusions: Our results underpin the role of land-use legacies in shaping soil microbial communities. The stronger plant-microbe linkages in ancient forest soils compared to post-agricultural secondary forest soils may contribute to a higher resilience against environmental changes. Our results advocate for more multifactor global change experiments that investigate the mechanisms underlying the potential effects of land-use legacies on plant-microbe relationships in forest. [ABSTRACT FROM AUTHOR]

The paper presents new paleobotanical data in combination with the results of radiocarbon dating obtained from organomineral deposits of the northern shore of Pechevalavato Lake (70°13′22.3″ N, 71°50′57.6″ E) in the Seyakha River basin and characterizing the dynamics of vegetation in the northern part of Central Yamal in the Holocene. It has been shown that a tree birch (Betula sect. Betula) grew in Yamal in the early Holocene (10.2–8.7 cal kyr BP) no less than 400 km north of the modern northern limit of distribution of Betula pubescens ssp. tortuosa. Favorable conditions for the existence of birch woodlands at this time were provided by a higher temperature of the growing season, exceeding the modern parameters of the warmest month of the summer season by approximately 3–4°C. At the end of the early Holocene (after 8.5 cal kyr BP), forest vegetation began to degrade, and open landscapes with diverse plant communities of the subarctic tundra and single trees in the river valley spread. About 6.5 cal kyr BP, the northern subarctic tundra began to form the zonal appearance of the study area in climatic conditions close to modern ones. [ABSTRACT FROM AUTHOR]

Several studies have investigated how nitrogen (N) addition changes N competition between focal plant species and soil microorganisms; still, the impact on community-level plant-microbial N competition and the underlying mechanisms remain unclear. We conducted a short-term (4 h) 15N labeling experiment in an alpine meadow subjected to 7 years of NH4NO3 additions (0, 5, 10, and 15 g N m−2 year−1), by monitoring changes in soil properties (e.g., pH, Al3+, NH4+, NO3−), microbial biomass (MB), plant community composition, root traits (e.g., root length, root area, specific root length), as well as the plant (nine focal species and at the community level) and microbial N uptake. Change in the N competition between the nine focal plant species and microorganisms following N addition depended on the species. At the community level, the N addition rate did not affect plant-microbial competition for NH4+ and NO3− (P > 0.05). Nitrogen addition directly decreased NH4+ competition (β = − 0.700) but indirectly increased because of improved plant uptake due to increased N availability (β = 1.214). Competition for NO3− was dependent on microbial uptake (β = − 0.953) and was influenced by opposing effects of increased N availability (β = 1.342) and reduced MB (β = − 0.439). Thus, the effects of increased soil N availability and suppressed MB on plant and microbial N competition offset each other, while the plant community had a negligible impact. Such responses should be taken into account for better predictions of the effect of N addition on net primary productivity and ecosystem stability. [ABSTRACT FROM AUTHOR]

The results of the study of the Algai archeological site in the Lower Volga region (Aleksandrov-Gai district, Saratov oblast) are presented. The Algai settlement of the Neo-Eneolithic period includes several cultural layers formed over the last eight thousand years. Anthropogenically transformed light chestnut carbonate soils are the modern background surface soils (Eutric Cambisol (Loamic, Protocalcic, Ochric)). Soil, paleosol, and paleobotanical methods and radiocarbon dating have been used in this study. The soil stratum is represented by stratigraphically separated multitemporal full-profile Holocene soils showing different rates of eolian sedimentation and soil formation, vegetation change, and anthropogenic loads in the study area. Paleosol and paleobotanical data indicate hat the natural environment of the territory was not stable throughout the Holocene, and dry steppes existed in the studied territory. The most active sedimentation and soil formation occurred in the middle of the Holocene during the AT-2 period. During the stages of climate aridization, active sedimentation and vegetation suppression took place, which led to the disappearance of people from this territory. The stages of climate humidization were expressed in epigenetic soil formation with the development of organo-accumulative horizons under diverse plant associations and rich species composition of wild animals. These stages were favorable for human habitation. The obtained materials attest to considerable changes in the environmental conditions of the studied area in the Holocene marked by different stages of soil development and accompanied by periodic migration of humans. Unlike the background surface soil, buried soils were formed under extremely arid conditions and are characterized by soda salinization. This study made it possible to obtain new data on the climatic, soil, and paleobotanical features of the studied region. [ABSTRACT FROM AUTHOR]

Progressive industrialisation and urbanisation in recent decades have dramatically affected the soil cover and led to significant changes in its properties, which inevitably affect the functioning of other components of the forest ecosystems. The total content of Pb, Cd, Zn, Fe, Cr, Cu, Ni, As, and Hg was studied in twenty-five plots at different heights in the topsoil (organic and humus horizons) formed from the Carpathian flysch in the area of the Silesian Beskids (Western Carpathians). The aim of this article is to analyse the spatial distribution of potentially toxic elements in the mountain forest topsoil in different types of plant communities and to determine the relationship between altitude and potentially toxic elements contamination. The soils studied are acidic or very acidic, with an average range of 3.8 (H2O) and 2.9 (KCl). Concentrations of the metals Cd, Zn, Fe, Cr, Cu, Ni, and Hg on the plots that were analysed are within the range of permissible standards for forest ecosystems in Poland, while Pb and As exceed the permissible standards for this type of ecosystem. Spearman's rank correlation coefficient showed a high correlation between Fe–Cr (r(32) = 0.879, Pb-Hg r(32) = 0.772, Ni–Cr r(32) = 0.738, Zn-Cd r(32) = 0.734, and Cu-Hg r(32) = 0.743, and a moderate statistically significant positive correlation between Cu-Pb r(32) = 0.667 and As-Pb r(32) = 0.557. No correlation was found between altitude and the occurrence of potentially toxic elements. The geo-accumulation index (Igeo) index, on the other hand, indicates that Pb, As, and Cd have the highest impact on soil contamination in all study plots: it classifies soils from moderately to strongly polluted. The enrichment factor (EF) obtained for As and Hg indicates significant-to-very high enrichment in all areas studied. The potential ecological risk index (PLI) calculated for the sites indicates the existence of pollution in all areas examined. The highest risk categories (considerable to very high) are associated with cadmium and mercury. [ABSTRACT FROM AUTHOR]

Background and Aims: Human-driven nitrogen (N) deposition can alter soil biogeochemistry and plant communities, both critical to soil biota. However, understanding the relative impact of the relationship between nutrient resources and plants on soil communities has been hindered by a lack of experimental manipulations of both factors. We hypothesized that soil nematode communities would be structured predominantly by N addition via overall increased abundance, decreased diversity, and compositional shifts to dominance of r-selected bacterial-feeding nematodes. In contrast, we expected plant effects to be less evident and restricted to nematodes directly associated with plants. Methods: We used a long-term (18-yrs) experiment in moist meadow alpine tundra involving N addition and codominant plant (nitrophilic Deschampsia cespitosa and nitrogen-sensitive Geum rossii) removal. We characterized nematode communities via 18S rRNA metabarcoding and used soil biogeochemistry, plant, and microbial variables to determine factors shaping their communities. Results: The N addition treatment increased overall nematode abundance, decreased diversity, and affected the composition of all nematode trophic groups. Overall, nematode communities shifted to dominance of bacterial-feeding nematode taxa adapted to N-enriched environments. The likely drivers of this shift were increased soil nitrate and lower pH. The direct effects of codominant plants were more limited, with only changes in Geum rossii appearing to affect nematode responses. Conclusion: Overall, nematode communities in N-limited alpine ecosystems are highly sensitive to increases in N availability, irrespective of the nature of N preferences of codominant plants. The resulting nematode community restructuring could signify future shifts in soil functioning throughout alpine landscapes. [ABSTRACT FROM AUTHOR]

The review is devoted to the study of the relationship between endophytic bacteria Bacillus spp. with plants, the nature and mechanisms of manifestation of response reactions of a plant organism in a community with bacteria to environmental stress factors. Information is presented on the influence of bacterial endophytes on the formation of mutualistic relationships between plants and other microorganisms.The conclusion is made about the need for an integrated approach to studying the effect of endophytic bacteria on a plant organism under the action of various stress factors and in the conditions of its interaction with other microorganisms. [ABSTRACT FROM AUTHOR]

This report contains the results of quantitative analysis of primary iridoid gentiopicroside, phenolic compounds, and flavonoids in the shoots, rhizomes, and roots of cross gentian (Gentiana cruciata L.) plants collected in natural phytocenoses of Alekseevskii, Zelenodol'skii, and Apastovskii raions in the Republic of Tatarstan. The content of phenolic compounds and flavonoids in herbs was determined spectrophotometrically. It was shown that the greatest content of phenolic compounds and flavonoids in above-ground parts was 19.4 and 10.80 mg/g in Zelenodol'skii and Alekseevskii raions and that in the rhizomes and roots was 8.53 and 1.96 mg/g in Apastovskii raion. By the method of high-performance liquid chromatography, it was shown that the greatest quantity of gentiopicroside (more than 9%) was accumulated in the underground part of plants, whereas the above-ground part contained approximately 6% of this compound. Thus, cross gentian growing in plant communities located in these raions differed in the content of biologically active substances, which probably depended on the joint effect of ecological and cenotic characteristics of habitats. The results of phytochemical analysis suggest that Apastovskii raion in the Republic of Tatarstan may be a promising locality for picking and preparing medicinal herbs with a high content of main iridoid gentiopicroside. [ABSTRACT FROM AUTHOR]

Soils of high mountains significantly differ in the soil organic matter (SOM) content, but the factors of such diversity are still not completely known. We have studied physicochemical and microbiological soil properties and have estimated parameters of standard material decomposition based on the Tea bag index (TBI)—stabilization factor (STBI) and decomposition constant (kTBI)—in 16 subalpine, alpine, and subnival plant communities of the Teberda National Park (northwestern Caucasus) We tested the following hypotheses: (1) SOM is one of predictors of STBI and kTBI in the high-mountain zone along with other physicochemical soil properties; (2) the SOM content is greater at high STBI and low kTBI; (3) the SOM content correlates with belowground plant productivity. The main gradients of the studied soils include moisture content (automorphic vs. hydromorphic soils) and the concurrent SOM accumulation, as well as the altitudinal gradient (a decrease of soil basal respiration with altitude). The enrichment in nitrogen (e.g. the SOM quality) of the labile fraction is the best predictor of the decomposition rate. The parameter STBI decreases with the increase in the total carbon content and loss on ignition, while the correlation between kTBI and SOM is positive only in automorphic soils. Thus, the soils rich in organic matter are characterized by low stabilization factor and relatively high decomposition rate. The SOM content in plant communities with herbaceous dominants is in positive correlation with the production of fine roots, which reflects the important role of productivity in organic matter accumulation. [ABSTRACT FROM AUTHOR]

Complex links between biotic and abiotic constituents are fundamental for the functioning of ecosystems. Although non-monotonic interactions and associations are known to increase the stability, diversity, and productivity of ecosystems, they are frequently ignored by community-level standard statistical approaches. Using the copula-based dependence measure qad, capable of quantifying the directed and asymmetric dependence between variables for all forms of (functional) relationships, we determined the proportion of non-monotonic associations between different constituents of an ecosystem (plants, bacteria, fungi, and environmental parameters). Here, we show that up to 59% of all statistically significant associations are non-monotonic. Further, we show that pairwise associations between plants, bacteria, fungi, and environmental parameters are specifically characterized by their strength and degree of monotonicity, for example, microbe–microbe associations are on average stronger than and differ in degree of non-monotonicity from plant–microbe associations. Considering directed and non-monotonic associations, we extended the concept of ecosystem coupling providing more complete insights into the internal order of ecosystems. Our results emphasize the importance of ecological non-monotonicity in characterizing and understanding ecosystem patterns and processes. [ABSTRACT FROM AUTHOR]

Large herbivores can exert pronounced top-down effects on plant communities in grassland ecosystems. Previous studies highlighted the importance of the composition and traits of living plants in regulating the impact of herbivores on plant community. However, there has been little consideration of whether and how plant litter, a ubiquitous "after-life" plant component, affects the outcome of herbivore grazing on grasslands. Here, we conducted a large-scale field experiment in temperate grasslands of northeastern China to investigate how standing plant litter influenced top-down effects of large herbivores (sheep; Ovis aries) on plant species richness, evenness, community composition, and productivity. We found that, in the presence of standing litter, sheep grazing significantly reduced living biomass of forbs by 56%, but have no effects on biomass of the dominant grass, Leymus chinensis. However, in the absence of standing litter, sheep shifted their diet preference from forbs to the grass L. chinensis, leading to a 36% decrease in the biomass of L. chinensis and a 21% decrease in total biomass. Such changes in foraging pressure on plant species led to competitive release that in turn significantly altered plant community composition and increased species evenness. Synthesis and applications. Our results demonstrate that standing litter can alter foraging behaviors of large herbivores and modifying the outcome of their top-down effects on plant community properties in grasslands. These cryptic but perhaps ubiquitous interactions between litter and herbivores may help us better understand the organization and dynamics of plant communities in the grazed grasslands, with important implications for developing effective management and conservation plans. [ABSTRACT FROM AUTHOR]

Parasitoids induce physiological changes in their herbivorous hosts that affect how plants respond to herbivory. The signature of parasitoids on induced plant responses to feeding by parasitized herbivores indirectly impacts insect communities interacting with the plant. The effect may extend to parasitoids and cause indirect interaction between parasitoids that develop inside different herbivore hosts sharing the food plant. However, this type of interactions among parasitoid larvae has received very little attention. In this study, we investigated sequential and simultaneous plant-mediated interactions among two host–parasitoid systems feeding on Brassica oleracea plants: Mamestra brassicae parasitized by Microplitis mediator and Pieris rapae parasitized by Cotesia rubecula. We measured the mortality, development time, and weight of unparasitized herbivores and performance of parasitoids that had developed inside the two herbivore species when sharing the food plant either simultaneously or sequentially. Plant induction by parasitized or unparasitized hosts had no significant effect on the performance of the two herbivore host species. In contrast, the two parasitoid species had asymmetrical indirect plant-mediated effects on each other's performance. Cotesia rubecula weight was 15% higher on plants induced by M. mediator-parasitized hosts, compared to control plants. In addition, M. mediator development time was reduced by 30% on plants induced by conspecific but not heterospecific parasitoids, compared to plants induced by its unparasitized host. Contrary to sequential feeding, parasitoids had no effect on each other's performance when feeding simultaneously. These results reveal that indirect plant-mediated interactions among parasitoid larvae could involve any parasitoid species whose hosts share a food plant. [ABSTRACT FROM AUTHOR]

Contents of C, N, and P and N : P and C : N ratios in plant leaves have been studied in four alpine phytocenoses of the northwestern Caucasus to find out whether the species encountered in these areas differ in chemical composition from random samples from the local flora or not and determine the significance of the values of these traits for dominance, as well as their phylogenetic conservation. The content of nitrogen is lower in the leaves of plants from alpine heaths and Festuca varia grasslands and higher in the leaves of species of Geranium–Hedysarum meadows and alpine snowbeds than in a random sample. Dominants of productive Geranium–Hedysarum meadows contain more nitrogen than nondominant species, while the opposite dependence has been recorded for the other communities. The leaves of the components of all communities except alpine snowbeds contain less phosphorus than a random sample. Dominants of alpine heaths have less phosphorus and Geranium–Hedysarum meadows have more phosphorus in the leaves than nondominant species. The C : N ratio in the leaves is higher than the random value in species of alpine heaths and Festuca varia grasslands and lower in other communities. The dominant species have higher C : N ratios than the other species in all communities except Geranium–Hedysarum meadows. The N : P ratio is higher than the random value in species of all communities except Festuca varia grasslands. All the traits except the C : N ratio have a significant phylogenetic signal. [ABSTRACT FROM AUTHOR]

The results of the palynological study of the Kurshskaya Formation stratotype (Primorsky quarry, Kaliningrad Oblast) are presented. The lower part of the Kurshskaya Formation (Member of "chocolate" clays) contains an assemblage of latest Eocene dinoflagellate cysts Areosphaeridium diktyoplokum, Glaphyrocysta semitecta, and Cordosphaeridium funiculatum. The formation is characterized by four spore-pollen assemblages: (1) latest Eocene Pinuspollenites–Inaperturopollenites–Sciadopityspollenites assemblage in the "chocolate" clays and in the lower part of brown sands; (2) early Oligocene Sequoiapollenites–Betulaepollenites betuloides assemblage in the lower part of the brown sands member; (3) early Oligocene Boehlensipollis hohli–Carpinipites carpinoides in the middle part of brown sands member; (4) late Oligocene–early Miocene Alnipollenites–Corylopollis assemblage in the upper part of the brown sands of the Kurshskaya Formation. In total, the Kurshskaya Formation is terminal Eocene–early Miocene in age. The lower part of the Zamland Formation, which overlies the Kurshskaya Formation, contains the presumably middle Miocene Pinuspollenites–Tricolporopollenites pseudocingulum–T. euphorii assemblage. Based on the obtained palynological data, the depositional settings at the end of the Eocene–Oligocene–early Miocene in the South Baltic region are reconstructed. The regression of the marine basin began as early as the end of the Priabonian, the climate was still quite warm and humid, close to subtropical. Mesophytic mixed coniferous-broad-leaved forests grew along the shores of the strait, lowlands were occupied by marsh vegetation. Cooling at the Eocene/Oligocene boundary resulted in the appearance of hemlock in plant communities and increase in the proportion of catkins (alder, birch, hornbeam). Presumably, in the late Oligocene–early Miocene, the proportion of small-leaved trees, especially alder and hazel, sharply increased in mesophytic forests, while the number of pine trees decreased. Wetter and warmer climatic conditions are assumed for the early Miocene: this time is characterized by an increase in the number of walnut, cypress, and Cyrillaceae. In the middle Miocene, the climate was still quite warm, but drier, and such moisture-loving species as Podocarpus, spruce, Glyptostrobus, and swamp cypress disappeared from plant communities. [ABSTRACT FROM AUTHOR]

Climate change, such as temperature and precipitation changes, is becoming increasingly obvious, and in this context, planting designs need to urgently consider future climate change in advance. A field experiment was conducted in Beijing, China, where the future precipitation is predicted to increase, and extra irrigation was used to simulate the future precipitation increase. The species richness of sown meadows, including spontaneous plants and sown plants, and the adaptive strategies of the communities were recorded under different types of design models and substrates. The results showed that precipitation increased the diversity of sown plants and resource-demanding spontaneous plants but had no significant effect on the dry matter content of the entire community of species. Moreover, the interactions among precipitation and substrate, especially the design models, were significant. Of the models, the three-layer model had the highest species richness and least invasive plants. In addition, increased precipitation significantly changed the functional strategy of the plant community away from ruderals and towards competitor-stress tolerant species. This study provides guidance for the design and management of naturalistic plant communities under climate change. [ABSTRACT FROM AUTHOR]

Salinization is a great threat to wetlands and freshwater ecosystems. Increased salinity can disturb native aquatic vegetation and provide an empty niche for invasion of non-native species. To understand the fate of aquatic flora under increased salinity levels, 14 dominant wetland species with different growth forms (submersed, amphibious, floating-leaved, emergent and woody/tree) were exposed to increased salinity conditions. The objective was to assess the salt tolerance threshold for each species and model their performance in response to a salinity gradient ranging from 0.2 to 20 parts per thousand (ppt). Plant growth and survival rate were analyzed using a nonlinear regression model to project sublethal salinity concentrations that would reduce biomass and visual quality of each species by 50% (LC50). Results showed that a few non-native species (alligatorweed: Alternanthera philoxeroides (Mart.) Griseb., torpedograss: Panicum repens L., and Brazilian peppertree: Schinus terebinthifolius Raddi) survived 20 ppt salinity, whereas all other native and non-native species perished at salinity below 10 ppt. Increased salinity can suppress salt-sensitive native plants and increase the opportunity of invasion for salt-tolerant non-native species. This suggests that alligatorweed, torpedograss and Brazilian peppertree pose a more significant threat to the ecosystem if salinity levels continue to increase in freshwater ecosystems and exacerbate the encroachment of non-native species into native plant communities. [ABSTRACT FROM AUTHOR]

The structuring of plant assemblages along environmental gradients is typically explained by shifts from competition (limiting similarity) to environmental filtering as the environment becomes more stressful. However, facilitation, weaker-competitor exclusion, environmental heterogeneity, and the colonization-competition tradeoff can also structure plant assemblages along gradients. These assembly processes act on different plant traits and organs, and their prevalence varies with respect to the spatial scale. Using patterns of functional diversity, coupled with patterns of species association at two spatial scales, here we discern the assembly processes that structure shrub communities in four localities along an aridity gradient of the Atacama Desert. At each site, we calculated functional dispersion indexes for above- and below-ground traits, and patterns of species association at a patch and neighborhood scale. Our results revealed that at the patch scale in intermediate levels of aridity, the dominant assembly process was within-site environmental heterogeneity. At the neighborhood scale, communities are assembled mainly through random processes. Nonetheless, in some communities, the dominant assembly process was competition via limiting similarity or exclusion of the weaker competitor, and these did not change along the gradient. Together, these results reveal that environmental heterogeneity and competition are the main drivers of plant community assembly in a hyper-arid environment. [ABSTRACT FROM AUTHOR]

Dead plant biomass from foundation plant species is fundamental for the survival of coastal salt marshes because dead biomass aids in the vertical accretion of the ecosystem. Fungi regulate the decomposition of dead biomass, and thus play an essential role for marsh survival. Despite their importance, little is known about the compositional and functional changes of fungal communities in plant matter throughout senescence and litter decomposition. Here, we analyzed how fungal communities and their functionality change in the foundation plant species Spartina patens, which builds vast amounts of dead plant biomass (thatch) on the soil surface. We analyzed the chemical and fungal properties of live biomass, standing dead biomass (dead biomass shortly after senescence), upper thatch (top layer of litter on the soil surface), and lower thatch (bottom layer of litter on the soil surface) during September and November of 2021. We found that the chemical and fungal properties of different S. patens biomass types followed a predictable litter decomposition pattern. Notably, live biomass, standing dead biomass, upper thatch, and lower thatch all hosted unique fungal communities and litter chemistry. Functional groups present in live biomass (pathogens, epiphytes, and mycoparasites) were lost during senescence and later replaced by diverse saprotrophs. The abundance of lignocellulose saprotrophs increased throughout decomposition, with the highest abundance occurring in lower thatch. These results suggest a predictable succession of fungal communities through the senescence and decomposition of the foundation species S. patens. Our study highlights the diversity of fungal communities in a disappearing foundation species. [ABSTRACT FROM AUTHOR]

The restoration of invasion-resistant plant communities is an important strategy to combat the negative impacts of alien invasions. Based on a systematic review and meta-analysis of seed-based ecological restoration experiments, here we demonstrate the potential of functional similarity, seeding density and priority effect in increasing invasion resistance. Our results indicate that native priority is the most promising mechanism to control invasion that can reduce the performance of invasive alien species by more than 50%. High-density seeding is effective in controlling invasive species, but threshold seeding rates may exist. Overall seeding functionally similar species do not have a significant effect. Generally, the impacts are more pronounced on perennial and grassy invaders and on the short-term. Our results suggest that biotic resistance can be best enhanced by the early introduction of native plant species during restoration. Seeding of a single species with high functional similarity to invasive alien species is unpromising, and instead, preference should be given to high-density multifunctional seed mixtures, possibly including native species favored by the priority effect. We highlight the need to integrate research across geographical regions, global invasive species and potential resistance mechanisms. A systematic review and meta-analyses of seed-based ecological restoration experiments identify native priority as a promising mechanism for controlling invasion of alien plant species, which can reduce the performance of invasive species by more than 50%. [ABSTRACT FROM AUTHOR]

Vermicomposting is an important strategy for restoring soil function and fertility. However, information on the effects of vermicompost application in intensive Pinelliaternata planting systems has rarely been reported. Here, we focus on the effects of different vermicompost levels and chemical fertilizer (CF) strategies on soil chemical properties, soil enzymes, and soil rhizosphere microbial communities (bacteria and fungi) in a field experiment. Compared to no added fertilizers (CK), vermicompost was more effective than the CF treatment in increasing P. ternata yield. We found that the 5 t ha−1 vermicompost treatment (VC2) significantly increased the tuber yield by 44.43% and 6.55% compared to the CK and CF treatment, respectively, and water-soluble exudates by 6.56% and 9.63% (P < 0.05). The vermicompost and CF treatments significantly increased the total phosphorus (TP), urease (Ure), and soil catalase (Cat) contents (P < 0.05). Compared to the vermicompost and CK treatments, the CF treatment significantly decreased soil organic carbon (SOC), C/N ratio, and soil acid phosphatase (Pac) (P < 0.05). Redundancy analysis (RDA) showed that Ure and total potassium (TK) were the major drivers in the bacterial community, whereas TP, total nitrogen (TN), Pac, and TK were the major drivers in the fungal community. We also found a positive correlation between soil enzyme activities, including between Ure and bacterial genera (Clostridium, Pseudoclavibacter, Stella, Hyphomicrobium, Mesorhizobium, and Adlercreutzia). In summary, vermicompost application promotes P. ternata soil microecosystems and improves soil fertility, soil enzyme activities, and rhizosphere microbial structure and function. Vermicomposting is a novel and promising approach to sustainable ecological cultivation of Chinese herbs via the promotion of soil properties and beneficial organisms. [ABSTRACT FROM AUTHOR]

Biotic interactions are key processes that strongly affect the performance of seedlings in plant communities. In this work, we evaluated the effect of grazing and shrubs on the emergence and establishment of seedlings with different life-forms (dicotyledonous and monocotyledonous) in a sub-humid grassland community. We delimited five areas of 25 m2 in which we established four permanent plots of 1.0 m2. Two plots were centered at shrubs (beneath the canopy) and two in open spaces (without shrubs). Half of the shrubs and open plots were fenced to avoid grazing. During two consecutive years we marked all emerged seedlings and followed their fate. Grazing promoted dicotyledonous seedling emergence but reduced establishment. On the contrary, shrubs reduced dicotyledonous emergence but enhanced establishment. We did not detect any effect of shrubs or grazing on the emergence of monocotyledonous seedlings. Most seedlings emerged during fall and winter and died during spring and summer. Recruitment from seeds in this grassland is rare and complex, involving biotic and abiotic factors, with different responses to grazing and shrubs depending on seedling life-form and ontogeny. [ABSTRACT FROM AUTHOR]

Pollinators mediate interspecific and intraspecific plant–plant indirect interactions (competition vs. facilitation) via density-dependent processes, potentially shaping the dynamics of plant communities. However, it is still unclear which ecological drivers regulate density-dependent patterns, including scale, pollination niches (i.e., the main pollinator functional group) and floral attractiveness to pollinators. In this study, we conducted three-year field observations in Hengduan Mountains of southwest China. By gathering data for more than 100 animal-pollinated plant species, we quantified the effect (positive vs. negative) of conspecific and heterospecific flower density on pollination at two scales: plot-level (4 m2) and site-level (100–5000 m2). Then, we investigated how pollination niches and floral attractiveness to pollinators (estimated here as average per-flower visitation rates) modulated density-dependent pollination interactions. Pollinator visitation depended on conspecific and heterospecific flower density, with rare plants subjected to interspecific competition at the plot-level and interspecific facilitation at the site-level. Such interspecific competition at the plot-level was stronger for plants pollinated by diverse insects, while interspecific facilitation at the site-level was stronger for bee-pollinated plants. Moreover, we also found stronger positive conspecific density-dependence for plants with lower floral attractiveness at the site-level, meaning that they become more frequently visited when abundant. Our study indicates that the role of pollination in maintaining rare plants and plant diversity depends on the balance of density-dependent processes in species-rich communities. We show here that such balance is modulated by scale, pollination niches and floral attractiveness to pollinators, indicating the context-dependency of diversity maintenance mechanisms. [ABSTRACT FROM AUTHOR]