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Plant phosphorus (P) acquisition strategy is considered to be an intrinsic driver behind plant succession. However, variations in plant P acquisition strategies in connection to soil P fraction changes after wetland drainage remain unclear. To address this issue, here we conducted a study in six distinct wetlands that experienced long‐term (>20 years) artificial drainage, with the adjacent waterlogged wetlands as a control. We analysed plant community composition, biomass and soil P fractions, and identified three plant P acquisition strategies based on soil acid phosphatase activity, plant P resorption efficiency, and soil arbuscular mycorrhizal fungi (AMF) content. We found that soil calcium‐bound P (PCa) and enzyme‐extractable P (Penzyme) were key factors influencing plant P acquisition. Soil PCa correlated negatively with acid phosphatase activity but positively with AMF content. Soil Penzyme negatively impacted P resorption efficiency. The wetlands were categorised into three types based on the change in plant richness and composition, with each exhibiting distinct plant P acquisition strategies. These changes in strategies after drainage corresponded with shifts in soil P fractions. Overall, our study highlights the role of soil P fractions in explaining plant P acquisition strategies after wetland drainage, suggesting P regulations on plant succession and ecosystem services. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Introduced Phragmites australis represents a widespread threat to North American wetlands. Management agencies invest millions of dollars annually to manage the species, mostly by applying herbicides, to mitigate and prevent negative impacts. The often temporary reduction of P. australis rarely increases native diversity, and long‐term legacy effects of P. australis and repeat herbicide treatments are unknown. We used a coordinated management program targeting mostly small P. australis populations in the Adirondack Park in New York State, United States, to assess the potential for such legacy effects. We planted individuals of three native species as sentinels into treated and untreated, uninvaded reference wetlands after unassisted succession had occurred in treatment areas. Sentinel plants survived and grew in treated areas, suggesting legacy of P. australis and its management did not permanently limit establishment of native plants. However, responses were variable among sentinel species, with negative or neutral impacts on survival rates and neutral or positive effects on growth. Species‐specific responses and large variation in survival rates between sites and sentinels indicate that site factors are a dominant influence on survival and growth. Importantly, as treatment frequency increased, survival of one sentinel species decreased significantly, indicating a potential for long‐term negative impacts of repeated herbicide applications. Additional replanting after P. australis treatment and initial unassisted plant succession may enable more diverse plant communities to return, including species not able to recruit from local seed banks or seed sources. However, it remains unclear if active transplanting will enable more long‐term suppression of P. australis. [ABSTRACT FROM AUTHOR]

Starting in the mid 1970's, researchers, industry leaders, and residents collaborated on one of the world's largest regreening programs in the industrial region of Sudbury, Canada. The Sudbury Regreening Recipe included the application of crushed dolomitic limestone, nitrogen–phosphorus–potassium fertilizers, grass–legume seed mixtures across 8200 ha, and subsequent tree planting across 25 000 ha of acidic metal-contaminated land. The current study evaluated shifts in understory vegetation diversity and soil geochemistry on a chronosequence of sites treated the same way between 1982 and 2012. Fifty-six plant species were identified across the 24 sites, only four of which were planted in the initial remediation effort. Key factors influencing plant community composition and diversity were related to shifts in soil properties over time: bulk density, LFH layer depth, and mineral soil horizon pH. Plant communities differed with stand age and rocky sites had significantly different plant communities and lower canopy cover than less rocky sites. Mineral soil horizon pH increased with age, reflecting the movement of applied dolomite in soil. Despite high concentrations of total copper and nickel in soil, plant succession patterns were generally similar to those in naturally recovering forests demonstrating the overall success of the restoration program. [ABSTRACT FROM AUTHOR]

Plant community succession can impact greenhouse gas (GHG) emissions from the soil by altering the soil carbon and nitrogen cycles. However, the effects of community landscape diversity on soil GHG emissions have rarely been fully understood. Therefore, this study investigated how plant landscape diversity, structure type, and species composition, affect soil GHG emissions in a riparian zone. Soil GHG emissions were assessed by measuring the air samples collected from four study sites, which have different plant community structure types and species compositions (natural sites with complex plants, landscaped sites with fruit trees and grasses, untended sites with ruderals, and farmland sites), using the static chamber method. Significant differences were observed in soil carbon dioxide (CO2; p < 0.001), nitrous oxide (N2O; p < 0.001), and methane (CH4; p = 0.005) emissions. The untended site with ruderals exhibited the highest CO2 emissions, while N2O emissions increased as plant community diversity decreased. All sites acted as sinks for CH4 emissions, with decreased CH4 uptake efficiency in more diverse plant communities. The Mantel test and variance partitioning analysis revealed soil microbial biomass as an indirect influencer of GHG emissions. This study could help predict soil GHG emissions and their global warming potential under future changes in the island riparian zones. [ABSTRACT FROM AUTHOR]

Litter-derived dissolved organic matter (DOM) plays an essential role in biogeochemical cycles. In wetlands, species relative abundance and its change have great influences on input features of litter-derived DOM, including chemical characteristics per se and functional diversity of chemical characteristics. Functional diversity is an important factor controlling organic matter biodegradation, but little is known in terms of the DOM. We mixed litter leachates of four macrophytes with a constant concentration (20 mg DOC L−1) but varying dominant species and volume ratios, i.e. 15:1:1:1 (low-evenness), 5:1:1:1 (mid-evenness), and 2:1:1:1 (high-evenness), generating a gradient of chemical characteristics and functional diversity (represented by functional dispersion index FDis). Based on a 42-d incubation, we measured degradation dynamics of these DOM mixtures, and analyzed potential determinants. After 42 days of incubation, the high-evenness treatments, along with mid-evenness treatments sometimes, had most degradation, while the low-evenness treatments always had least degradation. The degradation of mixtures related significantly to not only the volume-weighted mean chemical characteristics but also FDis. Furthermore, the FDis even explained more variation of degradation. The non-additive mixing effects, synergistic effects (faster degradation than predicted) in particular, on degradation of DOM mixtures were rather common, especially in the high- and mid-evenness treatments. Remarkably, the mixing effects increased linearly with the FDis values (r2adj. = 0.426). This study highlights the critical role of functional diversity in regulating degradation of mixed litter-derived DOM. Resulting changes in chemistry and composition of litter leachates due to plant community succession may exert substantial influences on biogeochemical cycling. [ABSTRACT FROM AUTHOR]

Understanding how plant functional traits respond to mining activities and impact metal(loid)s accumulation in dominant species is crucial for exploring the driving mechanisms behind plant community succession and predicting the ecological restoration potential of these plants. In this study, we investigated four dominant herbaceous species (Artemisia argyi, Miscanthus sinensis, Ficus tikoua, and Ageratina adenophora) growing on antimony (Sb) mining sites (MS) with high Sb and arsenic (As) levels, as well as non‐mining sites (NMS). The aim was to analyze the variations in functional traits and their contribution to Sb and As concentrations in plants. Our results indicate that mining activities enhanced soil nitrogen (N) limitation and phosphorus (P) enrichment, while significantly reducing the plant height of three species, except for F. tikoua. The four species absorbed more calcium (Ca) to ensure higher tolerance to Sb and As levels, which is related to the activation of Ca signaling pathways and defense mechanisms. Furthermore, plant Sb and As concentrations were dependent on soil metal(loid) levels and plant element stoichiometry. Overall, these findings highlight the regulatory role of plant element traits in metal(loid) concentrations, warranting widespread attention and further study in the future. [ABSTRACT FROM AUTHOR]

The Many-colored Rush Tyrant (Tachuris rubrigastra) and Wren-like Rushbird (Phleocryptes melanops) are birds that inhabit the subtropical salt marshes of Brazil, a newly recognized ecosystem of tidal marshes. We studied the habitat selection of these species in the subtropical salt marshes, characterizing the vegetation types where the species did and did not occur in the same habitats. The species occurred in a total of four very simplified vegetation types, characterized by the dominance of one or two plant species, including Schoenoplectus californicus, Crinum americanum, Cladium jamaicense, and Typha domingensis. We found that the habitats selected by the birds have very specific phytophysiognomic characteristics related to vegetation height and density. Moreover, the lower altitudes of certain areas of occurrence implies longer and higher flooding during periods of high tides; thus, the greater height of the vegetation maintains an above-water-level foraging and protective area for the birds. The fact that subtropical salt marshes are a transitional ecosystem suggests the possibility of rapid changes in plant succession or an intensification of the tropicalization process with mangrove expansion, which could eliminate habitat characteristics that are crucial to the survival of these two bird species in the subtropical salt marshes of Brazil. [ABSTRACT FROM AUTHOR]

Decadal scale lake drying in interior Alaska results in lake margin colonization by willow shrub and graminoid vegetation, but the effects of these changes on plant production, biodiversity, soil properties, and soil microbial communities are not well known. We studied changes in soil organic carbon (SOC) and nitrogen (N) storage, plant and microbial community composition, and soil microbial activities in drying and non‐drying lakes in the Yukon Flats National Wildlife Refuge. Historic changes in lake area were determined using Landsat imagery. Results showed that SOC storage in drying lake margins declined by 0.13 kg C m−2 yr−1 over 30 years of exposure of lake sediments, with no significant change in soil N. Lake drying resulted in an increase in graminoid and shrub aboveground net primary production (ANPP, +3% yr−1) with little change in plant functional composition. Increases in ANPP were similar in magnitude (but opposite in sign) to losses in SOC over a 30‐year drying trend. Potential decomposition rates and soil enzyme activities were lower in drying lake margins compared to stable lake margins, possibly due to high salinities in drying lake margin soils. Microbial communities shifted in response to changing plant communities, although they still retained a legacy of the previous plant community. Understanding how changing lake hydrology impacts the ecology and biogeochemistry of lake margin terrestrial ecosystems is an underexamined phenomenon with large impacts to landscape processes. Plain Language Summary: Lake dominated ecosystems in Alaska have experienced periods of widespread lake drying in the past. We understand little of what occurs on these new nearshore habitats following lake drying, especially changes in soil properties and soil microbial communities. Using a combination of remote sensing and field sampling on hundreds of lakes in the Yukon Flats National Wildlife Refuge, we learned that lake margin soils lose significant quantities of soil C in the decades following lake drying, and at the same time soils become increasingly saline and soil microbial activites are reduced. Overall, lake drying has large impacts on the surrounding ecosystems and it is important to understand these changes for management. Key Points: Lake drying in the Yukon Flats National Wildlife Refuge triggers a succession of plant and microbial communities and losses of lake margin soil organic carbon (SOC)Lake drying also results in increases in the salinity of lake margin soils, slowing rates of microbial activitiesAlthough lake drying resulted in losses of SOC, increases in Aboveground Net Primary Production (ANPP) compensated for these losses [ABSTRACT FROM AUTHOR]

Elucidating the water utilization strategy of trees during forest succession is a prerequisite for predicting the direction of forest succession. However, the water utilization characteristics of trees in forests across a successional gradient remain unclear. Here, we utilized the hydrogen and oxygen stable isotopes combined with the Bayesian mixed model (MixSIAR) to analyze the water utilization of dominant trees (Pinus massoniana, Castanea henryi, and Schima superba) in forests along a successional gradient in the Dinghushan Biosphere Reserve of China. Furthermore, we determined the primary factor affecting the water utilization of various trees based on variation partitioning analysis and a random forest model. Our results illustrated that in the early-successional forest, the water utilization ratios from shallow soil layers by P. massoniana were significantly lower than that in the mid-successional forest (51.3%–61.7% vs. 75.3%–81.4%), while its water utilization ratios from deep soil layers exhibited the opposite pattern (26.1%–30.1% vs. 9.0%–15.0%). Similarly, the ratios of water utilization from shallow soil layers by C. henryi (18.9%–29.5% vs. 32.4%–45.9%) and S. superba (10.0%–25.7% vs. 29.2%–66.4%) in the mid-successional forest were relatively lower than in the late-successional forest, whereas their water utilization ratios from deep soil layers showed the contrary tendency. Moreover, our results demonstrated that the diverse water utilization of each tree in different successional forests was mainly attributed to their distinct plant properties. Our findings highlight the increased percentage of water utilization of trees from shallow soil layers with forest succession, providing new insights for predicting the direction of forest succession under changing environments. [ABSTRACT FROM AUTHOR]

Investigating functional traits among mountain species with differing altitude requirements is integral to effective conservation practices. Our study aims to investigate the structural and chemical characteristics of Daphniphyllum macropodum leaves at three altitudes (1100 m, 1300 m, and 1500 m) across southern China to provide insight into changes in leaf functional traits (LFT) as well as plant adaptations in response to changing environmental conditions. Leaf structural characteristics include leaf thickness (LT), leaf area (LA), specific leaf area (SLA), and leaf tissue density (LD), respectively, while chemical properties include carbon-nitrogen-phosphorus (C:N:P) contents and ratios, such as C/N, C/P, and N/P. Our findings demonstrated the significant effect of altitude on both structural (LT, SLA, LD) and chemical aspects (N, C/N, N/P) of LFT. In particular, leaves at 1100 and 1300 m differed greatly, with 1300 m having lower SLA values than 1100 m. Observable trends included an initial increase followed by a decline as the altitude rose. Notable among them were the LT, LD, N, and N/P values at both locations. Traits at 1300 m were significantly higher than at 1100 m; SLA and C/N values displayed an inverse trend, with their lowest values occurring at 1300 m. Furthermore, this research demonstrated various degrees of variation among LFT, with structural traits exhibiting greater fluctuation than chemical traits. Robust correlations were observed among certain traits, such as LT, LD, and SLA. Furthermore, the interdependency relationships between N and C/N, as well as P and C/P, demonstrated interconnectedness. Redundancy analysis indicated that soil factors, specifically P content, exerted the strongest impact on LFT. At 1100 m, D. macropodum employed acquisition strategies; however, at 1300 m, conservation strategies emerged, showing a shift from acquisition strategies at lower altitudes to conservative strategies at higher ones. [ABSTRACT FROM AUTHOR]

While the succession of terrestrial plant communities is well studied, less is known about succession on dead wood, especially how it is affected by environmental factors. While temperate forests face increasing canopy mortality, which causes considerable changes in microclimates, it remains unclear how canopy openness affects fungal succession. Here, we used a large real-world experiment to study the effect of closed and opened canopy on treatment-based alpha and beta fungal fruiting diversity. We found increasing diversity in early and decreasing diversity at later stages of succession under both canopies, with a stronger decrease under open canopies. However, the slopes of the diversity versus time relationships did not differ significantly between canopy treatments. The community dissimilarity remained mainly stable between canopies at ca. 25% of species exclusively associated with either canopy treatment. Species exclusive in either canopy treatment showed very low number of occupied objects compared to species occurring in both treatments. Our study showed that canopy loss subtly affected fungal fruiting succession on dead wood, suggesting that most species in the local species pool are specialized or can tolerate variable conditions. Our study indicates that the fruiting of the fungal community on dead wood is resilient against the predicted increase in canopy loss in temperate forests. [ABSTRACT FROM AUTHOR]

Phosphorus (P) cycle plays a vital role in maintaining the structure and function of wetland ecosystems. However, research knowledge on high-altitude wetland ecosystems is very poor. In the present study, plant communities, soil P fractions and other properties and their transformation were investigated under the influence of four types of degradation categories, namely non-, light-, medium-, and severe degraded (ND, LD, MD, and SD, respectively) wetlands of Tibetan Plateau. The degradation of wetlands causes succession in the plant communities from wet to dry mesophytic communities, significantly reducing plant coverage and biomasses. As a result, soil water content (SWC), soil organic carbon (SOC), and soil total nitrogen (TN) contents decrease with increasing degradation. Plant P accumulation usually showed a decreasing trend with increasing levels of degradation. Soil total P, available P, inorganic P, Labile inorganic P, P mineralization rate, and alkaline phosphatase (ALP) concentration increased from non-degradation to light degradation and then declined until severe degradation. The redundancy analysis (RDA) ranking further revealed that labile organic P is the main source of soil available P and soil ALP play important role in P transformation. These results suggest that there prevails a nonlinear change on soil P pool and turnover rate to wetland degradation degree. The study thus provides a mechanistic understanding of alpine wetland degradation driven soil P dynamics and cycling, which would facilitate the restoration of nutrient-based degraded wetlands. [ABSTRACT FROM AUTHOR]

The complex interrelation between plants and geomorphic processes is described in the concept of biogeomorphic succession. While ecological research on succession and community assembly has transitioned towards functional approaches, studies on functional diversity in biogeomorphic settings, particularly in glacier forelands, remain limited. In this study, we investigated abundance of vascular plant species and functional traits in an alpine glacier foreland using data from 199 plots. Our objective was to unravel the development of functional diversity during biogeomorphic succession. Specifically, the study determined whether structural shifts in functional diversity are associated with stability thresholds related to plant cover, geomorphic influence, and examined trait spectra for stages of biogeomorphic succession. Our findings revealed a nonlinear trajectory of functional diversity along the plant cover gradient, marked by two distinct structural shifts at 30% and 74% cover, corresponding to established stability thresholds. Along the gradient of geomorphic influence, we observed an increase in functional diversity until 54% of the plot area was affected, beyond which functional diversity declined below the initial level. The analysis of community‐weighted means of traits across four stages of biogeomorphic succession determined by plant cover and absence and presence of geomorphic influence revealed significant differences in trait values. In the transition to the biogeomorphic stage, associated with the identified initial structural shift, there is a shift from a prevalence of above‐ground adaptation and reproductive traits, such as leaf longevity, structure, growth form and mixed reproductive strategies, to an increased dominance of competitor species and traits related to below‐ground structures, including root type and structures, as well as vegetative reproduction. Our results contribute to understanding the relationship between vegetation succession and geomorphic influence by linking them to plant functional traits. This study advances beyond traditional taxonomic investigations by emphasizing functional approaches to biogeomorphic succession. Moreover, the functional trait data used in this study, easily downloadable from a public repository, can serve as a valuable template for future research in (bio)geomorphology, along with the employed methodologies. [ABSTRACT FROM AUTHOR]

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow, which transfer substantial amounts of elements into the soil, influencing soil microbial community, plant survival, and plant community succession. Despite advancements in ecohydrological research, the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely unexplored. To address this gap, we conducted a systematic review of 1020 papers published between 2000 and 2022, gathering data on nutrient concentration and enrichment for critical ions (including K+, Na+, Ca2+, Mg2+, NH4+, Cl−, NO3− and SO42−) from the Web of Science and Chinese Knowledge Infrastructure databases. We aimed to synthesize the mechanisms, quantify the enrichments, and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones, and vegetation types and ecosystems. The results of this study indicate that stemflow exhibits, on average, 2.1 times greater ion concentration (6.13 mg L−1) compared to throughfall. In particular, among the investigated ions, SO42− (12.45 and 6.32 mg L−1) for stemflow and throughfall, respectively, and Cl− (9.21 and 4.81 mg L−1) exhibit the highest concentrations in both rainfall redistribution components, while K+ (13.7 and 5.8) and Mg2+ (5.6 and 2.8) have the highest enrichment factors. Across climate zones, throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid regions. Along the temperature gradient, ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing temperature. In addition, shrubs, conifers, mixed forests, and artificial ecosystems demonstrate enrichment factors 1.1 to 3.0 times greater than those of trees, broad- leaved plants, pure forests, and natural ecosystems. These findings emphasize the need for increased attentions to artificial ecosystems, such as urban and agricultural ecosystems, which often received limited research focus, especially regarding shrubs and conifers exhibiting stronger nutrients enrichment capabilities. Future investigations should integrate soil moisture analysis to better understand the impact of rainfall redistribution on the nutrient enrichment processes, patterns, and nutrient balance in global terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Coal mine heaps represent unique novel environments, suitable for studying plant succession and its influence on the activity of microbes inhabiting the rhizosphere. Our aim was to verify if the functional diversity and catabolic activity of soil microorganisms would increase along with the plant succession from non‐vegetated and forbs‐dominated to grass‐dominated communities. The study was conducted on coal mine heaps located in Upper Silesia (Southern Poland), focusing on non‐vegetated patches, patches dominated by forbs–Tussilago farfara and Daucus carota (in the early stages of succession), and by grasses–Poa compressa and Calamagrostis epigejos (in later stages of primary succession). The catabolic activity and functional diversity of soil microbial communities were analyzed based on community‐level physiological profiles using BIOLOG EcoPlatesTM and the activity of dehydrogenase, alkaline phosphatase, acid phosphatase, and urease. Our results showed that spontaneous vegetation on coal mine heaps strongly affects the physicochemistry of the substrate and the functional diversity of soil microbial communities. Grasses' rhizosphere was hosting more active and functional diversified microbial communities, while non‐vegetated and T. farfara‐vegetated patches were accompanied by a reduced development of soil microbiota. Furthermore, grasses were mainly associated with a substantial delivery of plant litter to the substrate, providing a source of carbon for microorganisms. [ABSTRACT FROM AUTHOR]

An emblematic symptom of climate change is the retreat of glaciers worldwide. As glaciers retreat, new terrains are exposed to colonization by a variety of organisms, leading to succession in plant communities and changes in soil properties. However, little is known about how the development of novel ecosystems emerging after glacier retreat depends on plant–soil interactions. Here, we investigated how glacier retreat influences the relationships between plant communities and soil functioning. We examined the diversity and structure of plant communities (functional composition, diversity, ecological indicators) and analyzed soil properties (pH, organic carbon, total nitrogen, C/N ratio, texture, available and total elements) along a glacier foreland comprising four stages of glacier retreat. The dominance of plant functional types shifts from herbaceous to shrubs and ultimately trees. Plant diversity initially increases after glacier retreat, along with an increase in soil organic matter and nutrients. Over 120 years, soils acidify at a rate of 0.02 units per year, the C/N ratio increases while plant diversity decreases. These findings provide novel evidence on the geo-ecological processes driving the development of new ecosystems that emerge from glacier retreat. As climate is warming and glaciers are retreating at increasing rates, pioneer herbaceous communities are quickly replaced by coniferous forests. As a result, biodiversity decreases while organic matter accumulation and soil acidity become more pronounced. We highlight that local plant–soil interactions should be the target of biodiversity conservation efforts and landscape management plans aimed at mitigating the impact of glacier extinction on biodiversity and ecological systems. [ABSTRACT FROM AUTHOR]

The soil seed bank is key to plant succession. However, agricultural activities have had a great impact on the vegetation and its composition. The aim was to determine the soil seed bank in different grazing agroecosystems in the central part of Veracruz state, Mexico. Richness, abundance, diversity, equity, dominance and similarity of the species were quantified and compared among four agroecosystems (silvopastoral, pasture-trees, traditional grazing, and Acahual or secondary vegetation) in Veracruz, Mexico during the year 2017. Samples were collected. of soil at two depths (0-5, > 5-10 cm). A statistical difference was found in the seed bank (P < 0.05) in silvopastoral at both depths, 0-5 (H’ = 2.13) and 5-10 (H’ = 1.86). Equity and dominance were higher for this agroecosystem (0.86) and for Acahual (0.58) with statistical differences (P < 0.05). No statistical differences were found at sites between depths (P > 0.05). Similarity was greater than 50% at all sites and increased with soil depth. The evidence suggests that the greatest diversity of the seed bank was in silvopastoral from 0 to 5 cm deep. The seed bank has potential for the restoration of vegetation, mainly herbaceous, and can promote the development of shrubs and trees, despite the management of cattle ranching sites.

Plant secondary succession has been explored extensively in restoring degraded grasslands in semiarid or dry environments. However, the dynamics of soil microbial communities and their interactions with plant succession following restoration efforts remain understudied, particularly in alpine ecosystems. This study investigates the interplay between soil properties, plant communities, and microbial populations across a chronosequence of grassland restoration on the Qinghai–Tibet Plateau in China. We examined five succession stages representing artificial grasslands of varying recovery durations from 0 to 19. We characterized soil microbial compositions using high-throughput sequencing, enzymatic activity assessments, and biomass analyses. Our findings reveal distinct plant and microbial secondary succession patterns, marked by increased soil organic carbon, total phosphorus, and NH4+-N contents. Soil microbial biomass, enzymatic activities, and microbial community diversity increased as recovery time progressed, attributed to increased plant aboveground biomass, cover, and diversity. The observed patterns in biomass and diversity dynamics of plant, bacterial, and fungal communities suggest parallel plant and fungal succession occurrences. Indicators of bacterial and fungal communities, including biomass, enzymatic activities, and community composition, exhibited sensitivity to variations in plant biomass and diversity. Fungal succession, in particular, exhibited susceptibility to changes in the soil C: N ratio. Our results underscore the significant roles of plant biomass, cover, and diversity in shaping microbial community composition attributed to vegetation-induced alterations in soil nutrients and soil microclimates. This study contributes valuable insights into the intricate relationships driving secondary succession in alpine grassland restoration. [ABSTRACT FROM AUTHOR]

Fishes are hosts for many microorganisms that provide them with beneficial effects on growth, immune system development, nutrition and protection against pathogens. In order to avoid spreading of infectious diseases in aquaculture, prevention includes vaccinations and routine disinfection of eggs and equipment, while curative treatments consist in the administration of antibiotics. Vaccination processes can stress the fish and require substantial farmer's investment. Additionally, disinfection and antibiotics are not specific, and while they may be effective in the short term, they have major drawbacks in the long term. Indeed, they eliminate beneficial bacteria which are useful for the host and promote the raising of antibiotic resistance in beneficial, commensal but also in pathogenic bacterial strains. Numerous publications highlight the importance that plays the diversified microbial community colonizing fish (i.e., microbiota) in the development, health and ultimately survival of their host. This review targets the current knowledge on the bidirectional communication between the microbiota and the fish immune system during fish development. It explores the extent of this mutualistic relationship: on one hand, the effect that microbes exert on the immune system ontogeny of fishes, and on the other hand, the impact of critical steps in immune system development on the microbial recruitment and succession throughout their life. We will first describe the immune system and its ontogeny and gene expression steps in the immune system development of fishes. Secondly, the plurality of the microbiotas (depending on host organism, organ, and development stage) will be reviewed. Then, a description of the constant interactions between microbiota and immune system throughout the fish's life stages will be discussed. Healthy microbiotas allow immune system maturation and modulation of inflammation, both of which contribute to immune homeostasis. Thus, immune equilibrium is closely linked to microbiota stability and to the stages of microbial community succession during the host development. We will provide examples from several fish species and describe more extensively the mechanisms occurring in zebrafish model because immune system ontogeny is much more finely described for this species, thanks to the many existing zebrafish mutants which allow more precise investigations. We will conclude on how the conceptual framework associated to the research on the immune system will benefit from considering the relations between microbiota and immune system maturation. More precisely, the development of active tolerance of the microbiota from the earliest stages of life enables the sustainable establishment of a complex healthy microbial community in the adult host. Establishing a balanced host-microbiota interaction avoids triggering deleterious inflammation, and maintains immunological and microbiological homeostasis. [ABSTRACT FROM AUTHOR]

Globally, habitat loss, deforestation, and climate change are mostly caused by land cover changes (LCC). The amount of land covered by trees has had a major impact on global warming and climate change. Increasing the amount of land cover helps to mitigate climate change and global warming. This study aims to investigate the changes in land cover and carbon storage in Plawangan Hill, Indonesia, over four years (2009, 2013, 2017, and 2023). The study site was defined as a conservation area that has been periodically impacted both directly and indirectly by volcanic eruptions. Images from Landsat 7 and 8 were used to collect data. Additionally, land cover changes were assessed using the forest canopy density (FCD Mapper) model, which was then utilized to quantify the carbon storage of the research site. The findings demonstrated fluctuations in land cover changes between 2009 and 2023. Additionally, changes in land cover have a direct impact on changes in carbon storage. The age of the trees, type of vegetation, succession stage, and history of eruptions were the variables that were apparent to be the main causes of these changes. [ABSTRACT FROM AUTHOR]

Root-associated microbiomes contribute to plant growth and health, and are dynamically affected by plant development and changes in the soil environment. However, how different fertilizer regimes affect quantitative changes in microbial assembly to effect plant growth remains obscure. Here, we explore the temporal dynamics of the root-associated bacteria of soybean using quantitative microbiome profiling (QMP) to examine its response to unbalanced fertilizer treatments (i.e., lacking either N, P or K) and its role in sustaining plant growth after four decades of unbalanced fertilization. We show that the root-associated bacteria exhibit strong succession during plant development, and bacterial loads largely increase at later stages, particularly for Bacteroidetes. Unbalanced fertilization has a significant effect on the assembly of the soybean rhizosphere bacteria, and in the absence of N fertilizer the bacterial community diverges from that of fertilized plants, while lacking P fertilizer impedes the total load and turnover of rhizosphere bacteria. Importantly, a SynCom derived from the low-nitrogen-enriched cluster is capable of stimulating plant growth, corresponding with the stabilized soybean productivity in the absence of N fertilizer. These findings provide new insights in the quantitative dynamics of the root-associated microbiome and highlight a key ecological cluster with prospects for sustainable agricultural management. Root-associated microbiomes contribute to plant growth and health. Here, the authors unveil the quantitative development of the root microbiome under unbalanced fertilization and highlight a key microbial cluster for soybean productivity. [ABSTRACT FROM AUTHOR]

The Qom Formation is the most important hydrocarbon reservoir target in Central Iran. The Qom platform developed in a back‐arc basin during the Oligo–Miocene due to the closing of the Tethyan Seaway. This formation consists of a variety of carbonate and non‐carbonate facies deposited on a platform ranging from supratidal to basin. A combination of tectonic and eustatic events led to some lateral and vertical facies variations in the study area. Six third‐order depositional sequences and related surfaces were identified regarding vertical facies changes in the studied sections of this Oligo–Miocene succession. According to all results and data, this succession was initially deposited during the Chattian upon a distally steepened ramp of siliciclastic‐carbonate composition, including the Bouma sequence. Then, from the late Chattian to the Aquitanian, the platform changed into a homoclinal carbonate ramp with a gentle profile. With respect to tectonic activity, this phase was a calm period during the deposition of the Qom Formation. Finally, a drowned carbonate platform and a rimmed shelf emerged during the Burdigalian, terminated by the continental deposits of the Upper Red Formation. Regarding all geological characteristics, three main tectono‐eustatic evolutionary phases have been recognized in the Qom back‐arc basin. [ABSTRACT FROM AUTHOR]

A powerful earthquake, particularly in mountainous regions, has the ability to trigger an immense number of landslides, resulting in severe damages. However, effectively assessing their recoveries in the years following the mainshocks has not yet been attempted due to the lack of continuously updated landslide inventories. Therefore, we proposed a novel detection framework utilizing time‐series Landsat images from 2000 to 2021, which enabled us to achieve a long‐term landslide inventory in the seismic zone for the first time. The response patterns of landslide development under different conditions were explored in detail. The restoration models were quantitatively established, revealing that the recoveries of post‐earthquake landslide activity and vital environmental indicators require a range from ∼5.29 to ∼25.00 years. This pioneering research is highly beneficial in comprehending the impact of earthquake‐induced hazards on short‐term land surface damage and long‐term ecological equilibrium. Plain Language Summary: The Wenchuan earthquake triggered tens of thousands of landslides and caused severe surface damages, leading to adverse impacts on the local environment in the following period. Therefore, we implemented an approach that combines change detection techniques with long‐term remote sensing images to track the landslide activities from 2000 to 2021. Consequently, continuous landslide maps have been produced, and the post‐earthquake landslide activities were analyzed under different conditions considering various factors. We also explored the restorations for the undisturbed landslides after the earthquake using important ecological indicators. The results suggest that the recovery of landslide activity and surface evapotranspiration was rapid. However, the regrowth and succession of damaged plants required a longer time. Moreover, it would take decades to fully restore the vegetation ecological function, which shatters our original impression on the persistence of post‐earthquake landslide impacts. Key Points: The inventories with over 21 years of continuous landslide activities prior to and following the Wenchuan earthquake were compiledApart from acknowledged attenuation, diverse environment exposed various evolutionary patterns of post‐earthquake landslide activityDamaged plant succession and ecological function restoration underwent lengthier durations than post‐seismic landslide stabilization [ABSTRACT FROM AUTHOR]

Background: Below-ground microbes mediate key ecosystem processes and play a vital role in plant nutrition and health. Understanding the composition of the belowground microbiome is therefore important for maintaining ecosystem stability. The structure of the belowground microbiome is largely determined by individual plants, but it is not clear how far their influence extends and, conversely, what the influence of other plants growing nearby is. Results: To determine the extent to which a focal host plant influences its soil and root microbiome when growing in a diverse community, we sampled the belowground bacterial and fungal communities of three plant species across a primary successional grassland sequence. The magnitude of the host effect on its belowground microbiome varied among microbial groups, soil and root habitats, and successional stages characterized by different levels of diversity of plant neighbours. Soil microbial communities were most strongly structured by sampling site and showed significant spatial patterns that were partially driven by soil chemistry. The influence of focal plant on soil microbiome was low but tended to increase with succession and increasing plant diversity. In contrast, root communities, particularly bacterial, were strongly structured by the focal plant species. Importantly, we also detected a significant effect of neighbouring plant community composition on bacteria and fungi associating with roots of the focal plants. The host influence on root microbiome varied across the successional grassland sequence and was highest in the most diverse site. Conclusions: Our results show that in a species rich natural grassland, focal plant influence on the belowground microbiome depends on environmental context and is modulated by surrounding plant community. The influence of plant neighbours is particularly pronounced in root communities which may have multiple consequences for plant community productivity and stability, stressing the importance of plant diversity for ecosystem functioning. [ABSTRACT FROM AUTHOR]

Early microbial colonization has a profound impact on host physiology during different stages of ontogeny. Although several studies have focused on early bacterial colonization and succession, the composition and role of fungal communities are poorly known in fish. Here, we sequenced the internal transcribed spacer 2 (ITS2) region of fungi to profile the mycobiome associated with the eggs, hatchlings and intestine of Atlantic salmon at various freshwater and marine stages. In most of the stages studied, fungal diversity was lower than bacterial diversity. There were several stage-specific fungal phylotypes belonging to different stages of ontogeny but some groups, such as Candida tropicalis, Saccharomyces cerevisiae, Alternaria metachromatica, Davidiella tassiana and Humicola nigrescens, persisted during successive stages of ontogeny. We observed significant changes in the intestinal fungal communities during the first feeding. Prior to first feeding, Humicola nigrescens dominated, but Saccharomyces cerevisiae (10 weeks post hatch) and Candida tropicalis (12 weeks post hatch) became dominant subsequently. Seawater transfer resulted in a decrease in alpha diversity and an increase in Candida tropicalis abundance. We also observed notable variations in beta diversity and composition between the different farms. Overall, the present study sheds light on the fungal communities of Atlantic salmon from early ontogeny to adulthood. These novel findings will also be useful in future studies investigating host-microbiota interactions in the context of developing better nutritional and health management strategies for Atlantic salmon farming. [ABSTRACT FROM AUTHOR]

During primary succession, the abundance of different species and their associated plant traits change over time. Understanding how plant traits linked to colonising and competitive abilities change through succession is important for determining whether community assembly can be predicted. Examining this across more than one taxon group can reveal if these patterns are generalisable.Here, we investigated primary succession on bare chalk for a chronosequence spanning 33 years for two different taxa, vascular plants and bryophytes. We examined how abundance changed through succession, and how this related to species' colonising and competitive abilities, using relevant plant traits for each taxa. A zero‐inflated beta regression model was used to investigate the effects of traits on both presence/absence and abundance‐when‐present of vascular plants and bryophytes.Vascular plants with a larger specific leaf area were more likely to occur later in succession. Vascular plants, which were hemicryptophytes, wind dispersing and had a lower canopy height, were more likely to increase in abundance‐when‐present during succession.Bryophytes with a larger spore diameter were more likely to occur later in succession. Shorter bryophytes with a greater frequency of sporophyte production had a higher abundance early in succession, representing their high colonising abilities. Whereas later in succession larger bryophytes, with a mat or weft life form and low sporophyte frequency were more abundant, indicating a shift towards greater competitive abilities.Synthesis. This study has revealed different patterns for vascular plants and bryophytes regarding colonisation and changes in abundance through succession, and the associated traits linked to colonising and competitive abilities. Although some traits were found to influence abundance through succession for vascular plants, these were often contrary to the expected pattern representing the change from colonising to competitive abilities, whereas for bryophytes, there was more evidence for this shift with successional age. This suggests that general theories on succession‐linked plant traits should not be relied upon in isolation for the prediction of community assembly. Context, particularly successional age in relation to the available species pool is also key. [ABSTRACT FROM AUTHOR]

Soil nutrients are regarded as limiting factors of the net primary productivity (PPN) of tropical forests. In this sense, it has been suggested that, in initial successional stages, the PPN is limited by N, as well as by P in late stages. To test this hypothesis, litter production and nutrient content were measured for five fertilization treatments (control, N, P, K, and NPK) in mature and post-mining forests of the Biogeographic Chocó. It was determined that the post-mining litter production was higher with the application of N, K, and NPK, whereas, in mature forests, it was higher with the application of N. In addition, a significant effect of the application of N on the post-mining foliar N content was recorded. In conclusion, a multiple nutritional limitation of the PPN was evidenced in early successional stages, which denotes a change in the limitation with succession. [ABSTRACT FROM AUTHOR]

The construction and operation of onshore wind farms interfere with the succession of local plant communities, and the impacts on the local ecology and climate are of great concern. The study of the relationships between onshore wind farms and local ecology and climate, as well as the accurate assessment of the impacts of onshore wind farms on local areas, are the foundation for promoting the sustainable development of green energy. In this study, we summarize the existing research methods used for field data monitoring, remote sensing data inversion and numerical model simulation, and found that onshore wind farms have obvious impacts on the local vegetation index, near-surface temperature, wind speed, soil moisture, and other parameters. Onshore wind farms reduce the local soil moisture content, increase the near-surface air temperature, and significantly alter local wind speeds. They also cause a reduction in the local vegetation index, inhibition of plant growth, and an increase in the mortality rates of birds and bats inside the wind farms. However, onshore wind farms have positive effects on the plant communities outside the wind farms, especially in the downwind direction. Overall, there is regional variability in the results and the findings are not generalizable. The mechanisms by which the onshore wind farms influence the local climate, the impact of climate on local ecology, and the direct effects of onshore wind farms on local ecology have not been clearly and accurately explained. Related research is still needed to further improve the precision, accuracy, and continuity of observational data. The construction of modeling systems also needs to incorporate indicators such as land use type, local microclimatic indicators, and plant species. Based on these considerations, this review provides support for macroscopically understanding the impacts of onshore wind farms on climate and ecology. [ABSTRACT FROM AUTHOR]

Phytoremediation can be a cost-effective method of restoring contaminated soils using plants and associated microorganisms. Most studies follow the impacts of phytoremediation solely across the treatment period and have not explored long-term ecological effects. In 1995, a phytoremediation study was initiated near Fairbanks, Alaska, to determine how the introduction of annual grasses and/or fertilizer would influence degradation of petroleum hydrocarbons (PHCs). After one year, grass and/or fertilizer treated soils showed greater decreases in PHC concentrations compared to untreated plots. The site was then left for 15 years with no active site management. In 2011, we re-examined the site to explore the legacy of phytoremediation on contaminant disappearance, as well as plant and soil microbial ecology. We found that the recruited vegetation, along with current bulk soil microbial community structure and function were all heavily influenced by initial phytoremediation treatment. The number of diesel-degrading microorganisms (DDM) was positively correlated with increasing amounts of vegetation on the site, and inversely correlated with PHC concentrations. Even 15 years later, the initial use of fertilizer had significant effects on microbial biomass and microbial community structure activities. We conclude that phytoremediation treatment has long-term, legacy effects on the plant community, which, in turn, impacts microbial community structure, function, and continued TPH disappearance. It is therefore important to consider phytoremediation strategies that not only influence site remediation rates in the short-term, but that also prime the site for restoration of vegetation across the long-term. [ABSTRACT FROM AUTHOR]

Plant–plant interactions under extreme environmental stress are still controversial. The stress gradient hypothesis (SGH) proposes that facilitation prevails under extreme environmental stresses, while an alternative view states that facilitation collapses or even switches back to competition at the extreme end of stress gradients. However, how the relationship between plant–plant interaction and periodic extreme flooding stress varies and its underlying mechanism are still unclear in a dam-regulated riparian ecosystem. We established a controlled experiment using two dominant species pairs (Cynodon dactylon–Cyperus rotundus and C. dactylon–Xanthium sibiricum) in the water level fluctuating zone of the Three Gorges Dam to examine their growth responses to the periodic extreme flooding stress. The results showed that as flooding stress increased, the competitive effect of C. dactylon on X. sibiricum shifted to facilitation, whereas the effect of X. sibiricum on C. dactylon maintained a strong inhibition. The plant height of X. sibiricum was the most important driver of the interaction between X. sibiricum and C. dactylon along the flooding gradient. The net effect of C. dactylon on C. rotundus shifted from neutral to negative, and the inhibitory effect of C. rotundus on C. dactylon became stronger at the extreme end of flooding stress. The root biomass of the two species was the key trait regulating their interaction with increasing flooding stress. Overall, the SGH was partially supported along our periodic extreme flooding stress gradient. Aboveground resource (light) might be the dominant factor driving the response of the interaction between annual plants and perennial clonal plants to periodic flooding stress, whereas belowground resource (water and nutrients) was probably the dominant factor for perennial clonal plants. Our study will help to further understand the environmental responses of plant–plant relationships and their regulatory mechanism, and the succession of riparian plant communities under extreme environmental changes, providing a basic theoretical basis and data support for the ecological restoration and management of riparian wetland vegetation. [ABSTRACT FROM AUTHOR]

A domination of generalist predators in soil communities suggests a wide overlap in their prey spectra, resulting in a probability of tense trophic relationships within the predator complex, in particular during the periods of prey scarcity caused by natural community reorganisations or anthropogenic disturbance. It has been argued that soil physical structure (e.g. pore size and connectivity) can limit interactions between the potential trophic competitors facilitating their coexistence (Erktan et al., 2020). Another possible mechanism of coexistence of generalist predators would be a variation in their life history traits resulting in a certain partitioning of their trophic niches. On an example of a field experiment studying soil mesofauna succession in decomposing plant remains, we compared potential trophic spectra of the abundant predators (firstly, gamasid mites), outlined by significant correlations of their densities with densities of other members of the community. A wide variation of potential prey objects was revealed for the major predators which thus should be treated as generalist feeders with activities spanning over several trophic levels. At the same time, the predators were characterised by individual spectra of the potential prey taxa and a low interspecific similarity between these spectra. The results suggest a certain differentiation of trophic niches in the mesofauna predatory complex. In addition, the prey spectra underwent temporal changes in the course of mesofauna succession, indicating possible switching of predators between the prey objects in response to environmental changes during the decay process. [ABSTRACT FROM AUTHOR]

New approaches to studying and monitoring of on palsa mires the Kola Peninsula are considered. Because of the observed signs of permafrost degradation in frost heave mounds (palsa), such objects can serve as markers of significant climate anomalies and shifts taking place in the Arctic zone. The analysis of the occurrence of palsa mires on the Kola Peninsula showed the existence of four separate morphometric and climatic clusters. The obtained results demonstrated the potential of a set of methods for determining the dynamics of permafrost in the palsa and for monitoring the related transformation of the mire ecosystem. [ABSTRACT FROM AUTHOR]

In primary successions, assembling plant communities are key for ecosystem functioning and stability. Often, plant successions are described on a taxonomic, functional and/or phylogenetic level, where species' identities, traits or evolutionary histories are considered. In this study, we exploited community features characterizing whole plant assemblages to capture emerging properties only available at the community level. Next to features aggregating over multiple plant species, we used a customized multispectral 3D plant scanner extracting digital community features as proxies for the frequency distribution of traits, productivity, prevalence of plant competition, and plant strategies and functions. Using these community features, we provide a comprehensive description of plant successions along glacier forefield. Additionally, we used a community feature‐based framework assessing the covariance of community feature dissimilarities and environmental dissimilarity to explore the mechanisms underlying plant community assemblies. Our data indicate a shift from fast‐growing and acquisitive, to slow‐growing and conservative plant strategies; increased productivity; higher competition between plant species; and an increasing contribution to the biogeomorphic stability along the successional gradient. Our results further indicate that stochastic processes dominate in early succession, whereas communities are mainly shaped by deterministic processes including environmental filtering and species interactions at late succession. We conclude that assessments of plant community features, facilitated by the use of field‐ready 3D scanners, provide complementary information to trait‐based approaches on the species level with implications for ecological processes. [ABSTRACT FROM AUTHOR]

Succession is a fundamental concept in ecology because it indicates how species populations, communities, and ecosystems change over time on new substrate or after a disturbance. A mechanistic understanding of succession is needed to predict how ecosystems will respond to land‐use change and to design effective ecosystem restoration strategies. Yet, despite a century of conceptual advances a comprehensive successional theory is lacking. Here we provide an overview of 19 successional theories ('models') and their key points, group them based on conceptual similarity, explain conceptual development in successional ideas and provide suggestions how to move forward. Four groups of models can be recognised. The first group (patch & plants) focuses on plants at the patch level and consists of three subgroups that originated in the early 20th century. One subgroup focuses on the processes (dispersal, establishment, and performance) that operate sequentially during succession. Another subgroup emphasises individualistic species responses during succession, and how this is driven by species traits. A last subgroup focuses on how vegetation structure and underlying demographic processes change during succession. A second group of models (ecosystems) provides a more holistic view of succession by considering the ecosystem, its biota, interactions, diversity, and ecosystem structure and processes. The third group (landscape) considers a larger spatial scale and includes the effect of the surrounding landscape matrix on succession as the distance to neighbouring vegetation patches determines the potential for seed dispersal, and the quality of the neighbouring patches determines the abundance and composition of seed sources and biotic dispersal vectors. A fourth group (socio‐ecological systems) includes the human component by focusing on socio‐ecological systems where management practices have long‐lasting legacies on successional pathways and where regrowing vegetations deliver a range of ecosystem services to local and global stakeholders. The four groups of models differ in spatial scale (patch, landscape) or organisational level (plant species, ecosystem, socio‐ecological system), increase in scale and scope, and reflect the increasingly broader perspective on succession over time. They coincide approximately with four periods that reflect the prevailing view of succession of that time, although all views still coexist. The four successional views are: succession of plants (from 1910 onwards) where succession was seen through the lens of species replacement; succession of communities and ecosystems (from 1965 onwards) when there was a more holistic view of succession; succession in landscapes (from 2000 onwards) when it was realised that the structure and composition of landscapes strongly impact successional pathways, and increased remote‐sensing technology allowed for a better quantification of the landscape context; and succession with people (from 2015 onwards) when it was realised that people and societal drivers have strong effects on successional pathways, that ecosystem processes and services are important for human well‐being, and that restoration is most successful when it is done by and for local people. Our review suggests that the hierarchical successional framework of Pickett is the best starting point to move forward as this framework already includes several factors, and because it is flexible, enabling application to different systems. The framework focuses mainly on species replacement and could be improved by focusing on succession occurring at different hierarchical scales (population, community, ecosystem, socio‐ecological system), and by integrating it with more recent developments and other successional models: by considering different spatial scales (landscape, region), temporal scales (ecosystem processes occurring over centuries, and evolution), and by taking the effects of the surrounding landscape (landscape integrity and composition, the disperser community) and societal factors (previous and current land‐use intensity) into account. Such a new, comprehensive framework could be tested using a combination of empirical research, experiments, process‐based modelling and novel tools. Applying the framework to seres across broadscale environmental and disturbance gradients allows a better insight into what successional processes matter and under what conditions. [ABSTRACT FROM AUTHOR]

The environmental impacts of microplastics (MPs) and nanoplastics (NPs), and their occurrence in aquatic, terrestrial, and aerial biomes have engrossed global attention. Most impact assessment studies have majorly linked the ecological hazards of MPs with the leaching of their additives, and the sorption and transport of co-contaminants due to prolonged environmental exposure. However, it is unclear whether the fresh (unaged) polymers themselves could significantly impact the biota. In this study, we have reported the impacts of virgin polypropylene (PP), polyvinyl chloride (PVC), and polylactic acid (PLA) MPs (0%, 0.05%, 0.1%, and 0.5% w/w dry soil) on the germination of an agricultural herb, coriander (Coriandrum sativum L.), under outdoor (field pots) and indoor (greenhouse) conditions. We observed that all three polymeric MPs in the soil delayed the germination (60–100% inhibition up to day 7) and impacted the seedling length within the 30-day exposure. The inhibitory effect was higher in the field than in the greenhouse. PVC showed the highest inhibition of germination under both conditions, followed by PP and PLA. PLA impaired the root length of the seedlings more than PP and PVC. At 0.5% (w/w), all polymers showed significantly elevated levels of reactive oxygen species in the root tips than control, suggesting MP-induced oxidative stress as a potential mechanism behind the impaired germination and seedling growth. These results clearly indicated a potential decline in crop survival and productivity caused by virgin MPs. The findings proposed that the soil MPs could be a global threat to the plants and ecosystem succession. [ABSTRACT FROM AUTHOR]

In cut flowers, xylem occlusion or blockage by bacteria negatively affects water balance and postharvest quality. Many studies have used culture-based methods to examine bacterial populations in vase water and their effects on flower longevity. It is still unclear if and how bacterial communities at the 16S rRNA gene (16S) level change during the vase period and how such change might correlate with postharvest longevity. This study compared the sequences of 16S amplicons from 4 different types of flowers and their vase water over the course of 7 days (Rosa spp., Gerbera jamesonii, and two Lilium varieties). The relative abundance of plant chloroplast and mitochondria 16S decreased significantly over the course 7 days in all 4 flowers as bacterial diversity increased. Richness and evenness of the bacterial communities increased over time, as did the number of rare taxa and phylogenetic diversity. Bacterial communities varied with time, as well as by flower source, types, and sample location (water, stem surface, whole stem). Some taxa, such as Enterobacteriacea and Bradyhizobiaceae decreased significantly over time while others such as Pseudomonas spp. increased. For example, Pseudomonas veronii, implicated in soft rot of calla lily, increased in both whole stem samples and water samples from Gerbera jamesonii. Erwinia spp., which includes plant pathogenic species, also increased in water samples. This work highlights the dynamic and complex nature of bacterial succession in the flower vase ecosystem. More work is needed to understand if and how bacterial community structure can be managed to improve cut flower vase life. [ABSTRACT FROM AUTHOR]

Aims: The influence of priority effects on plant community succession is increasingly discussed in community ecology. However, most grassland restoration approaches involving seed addition transfer all target species at the same time. Our objective was to tackle the question: does the order of arrival influence the establishment of restored communities? Location: La‐Bâtie‐Neuve, Southern Alps, France. Methods: We applied sequential sowing using two groups, one set of dominant species and one set of subordinate species, each comprising three different perennial plant species. We tested four sowing treatments: control (without any sowing), two sequential sowing treatments (dominants first or subordinates first) and synchronous sowing. We analysed plant cover each year for three years after sowing and calculated priority and earliness indices (the third year) for each group and each sown species. Results: Manipulating the order of arrival shaped community composition and trajectories. Some species of both groups were positively affected by being sown first compared to being sown synchronously. However, dominant and subordinate groups differed in their earliness index, showing a significant benefit for subordinates to be sown first. The subordinate species Onobrychis viciifolia and Plantago lanceolata established only when they were sown first, while Festuca cinerea showed greater establishment when sown first and simultaneously, compared to late sowing. The dominant Anthyllis vulneraria was not affected by date or type of sowing. However, the cover of the most dominant Bromopsis erecta was lower when being sown second, allowing a control of its dominance by delayed sowing. Conclusion: The strength of priority effects differs between species, which may depend on niche characteristics or microenvironment, influencing (negatively or positively) the establishment of late‐arriving species and affecting their competitive abilities. Our study provides evidence that plant community assembly was influenced by the order of arrival, but demonstrated a strong species‐specific response to priority effects. [ABSTRACT FROM AUTHOR]

In integrated crop‐livestock‐forestry (ICLF) systems, an agroforestry model, the forestry component influences the distribution of photosynthetically active radiation (PAR) and alters grain productivity. The aim of this study was to evaluate the effects of systematic and selective thinning of eucalyptus stands on the productivity of soybean and maize grown. The randomized block‐designed experiment comprised three treatments, namely crops grown under full sunlight (CFS) and in ICLF plots subjected to systematic and selective thinning to leave single‐row (ICLFS) and triple‐row (ICLFT) tree configurations. Soybean and maize were planted in succession between the tree stands and PAR incidence/transmittance and crop productivities were evaluated in the north and south sun‐exposed faces of the plots during three cultivation cycles after thinning. In comparison with CFS, PAR transmittance in the ICLF systems decrease varied according to the time of day, period of the year, distance of the sampling position from the trees, the sun‐exposed area (north and south faces) and time after thinning. Soybean productivities in ICLFS were similar to those of CFS in the first and second crop cycles, but significantly lower (p < 0.05) in the third crop cycle. In the ICLFT system, soybean productivity was similar to that of CFS in the second crop cycle but significantly lower in the first and third crop cycles. With regard to the maize crop, productivities decreased in the order CSF > ICLFS > ICLFT in all cultivation cycles. Our results showed that PAR transmittance and soybean/maize productivities were positively influenced by thinning of eucalyptus stands, particularly in ICLFS system. [ABSTRACT FROM AUTHOR]

Parasitoids are an important group of insects because their species number is among the highest. Multiple studies have addressed the relationships between forest successional age and insect diversity by focusing on herbivorous organisms, but changes in diversity of parasitoids are still poorly known. This work analyses the diversity of parasitoids in tropical forests representing three successional stages. A total of 30 traps were placed, ten in each forest successional stages. We estimated true diversity of Ichneumonidae species and guilds and explored the relationship between their diversity and the abundance of plant species using an Indicator Species Analysis; the relationship between parasitoid species and plant richness and abundance was tested using a Redundancy Analysis. A total of 1522 individuals and 168 morpho-species were captured in four months. Species richness showed no differences; however, parasitoid abundance was higher in young forest, while intermediate forest had the highest true diversity values (1 D) with 71.6 effective species. According to insect guilds, richness, abundance, and diversity were similar in the three vegetation successional stages. This finding may be explained based on the intermediate disturbance hypothesis, which postulates that moderate disturbance levels favor the highest diversity. In conclusion, successional age matters, i.e., diversity is the highest in intermediate stages, while the old forests harbors guilds unique to that successional stage, such as parasitoids of melitophagous larvae of bees. Other successional stages were characterized by a single species of parasitoid, belonging to the genera Eiphosoma and Anomalon, which may indicate altered and preserved forests, respectively. [ABSTRACT FROM AUTHOR]

Habitat filtering, species interactions and neutral colonization as well as extinction dynamics govern the sequence of community assembly and functional diversity (FD) during primary plant succession. To study the factors that influence changes in FD we here use data on plant seed size, seed numbers and specific leaf area from 107 study plots along a 7 year sequence of primary succession (2005–2011) in a 6 ha German artificial catchment. We show that the temporal variability in functional diversity can be partitioned into the effects of trait expression, species richness and plant cover. We observed a dominant role of species richness and community composition on FD. Trade-offs in the influence of species richness and plant cover tended to decrease the change in FD. Average FD steadily increased during the first 4 years of succession (2005–2008). The degree of annual changes in FD were highly plot specific. Average change in FD was comparatively low during the first 4 years and later high. Soil characteristics and light conditions did not significantly influence the detectable change in functional diversity. We conclude that the high plot-specific spatial variability of the annual changes in FD transformed the initially catchment-wide homogeneous distribution of plant species into a mosaic of very different local plant communities. Our partitioning results also indicate that the successional sequences in FD are in accordance with a hidden Markov series. [ABSTRACT FROM AUTHOR]

Summary: Rhizomicrobiome plays important roles in plant growth and health, contributing to the sustainable development of agriculture. Plants recruit and assemble the rhizomicrobiome to satisfy their functional requirements, which is widely recognized as the 'cry for help' theory, but the intrinsic mechanisms are still limited.In this study, we revealed a novel mechanism by which plants reprogram the functional expression of inhabited rhizobacteria, in addition to the de novo recruitment of soil microbes, to satisfy different functional requirements as plants grow. This might be an efficient and low‐cost strategy and a substantial extension to the rhizomicrobiome recruitment theory.We found that the plant regulated the sequential expression of genes related to biocontrol and plant growth promotion in two well‐studied rhizobacteria Bacillus velezensis SQR9 and Pseudomonas protegens CHA0 through root exudate succession across the plant developmental stages. Sixteen key chemicals in root exudates were identified to significantly regulate the rhizobacterial functional gene expression by high‐throughput qPCR.This study not only deepens our understanding of the interaction between the plant–rhizosphere microbiome, but also provides a novel strategy to regulate and balance the different functional expression of the rhizomicrobiome to improve plant health and growth. [ABSTRACT FROM AUTHOR]

Endophytes are essential in plant succession and evolution, and essential for stress resistance. Coralloid root is a unique root structure found in cycads that has played a role in resisting adverse environments, yet the core taxa and microbial community of different Cycas species have not been thoroughly investigated. Using amplicon sequencing, we successfully elucidated the microbiomes present in coralloid roots of 10 Cycas species, representing all four sections of Cycas in China. We found that the endophytic bacteria in coralloid roots, i.e., Cyanobacteria, were mainly composed of Desmonostoc_PCC-7422, Nostoc_PCC-73102 and unclassified_f__Nostocaceae. Additionally, the Ascomycota fungi of Exophiala, Paraboeremia, Leptobacillium, Fusarium, Alternaria, and Diaporthe were identified as the core fungi taxa. The Ascomycota fungi of Nectriaceae, Herpotrichiellaceae, Cordycipitaceae, Helotiaceae, Diaporthaceae, Didymellaceae, Clavicipitaceae and Pleosporaceae were identified as the core family taxa in coralloid roots of four sections. High abundance but low diversity of bacterial community was detected in the coralloid roots, but no significant difference among species. The fungal community exhibited much higher complexity compared to bacteria, and diversity was noted among different species or sections. These core taxa, which were a subset of the microbiome that frequently occurred in all, or most, individuals of Cycas species, represent targets for the development of Cycas conservation. [ABSTRACT FROM AUTHOR]

The fungal fruiting body is the organized mycelium. Tissue isolation and mycelium succession are common methods of fungal species purification and rejuvenation in the production of edible mushrooms. However, repeated succession increases strain degeneration. In this study, we examined the effect of repeated tissue isolation from Volvariella volvacea fruitbodies on the occurrence of degeneration. The results showed that less than four times in succession improved production capacity, however, after 12 successions, the traits indicating strain degeneration were apparent. For instance, the density of aerophytic hyphae, hyphal growth rate and hyphal biomass were gradually reduced, while the hyphae branching was increased. Also, other degenerative traits such as prolonged production cycles and decreased biological efficiency became evident. In particular, after 19 successions, the strain degeneration became so severe no fruiting bodies were produces anymore. Meanwhile, with the increase in successions, the antioxidant enzyme activity decreased, reactive oxygen species (ROS) increased, the number of nuclei decreased, and the mitochondrial membrane potential decreased along with morphological changes in the mitochondria. This study showed that repeated tissue isolation increased oxidative damage in the succession strain due to the accumulation of ROS, causing cellular senescence, in turn, degeneration in V. volvacea strain. [ABSTRACT FROM AUTHOR]

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Variation in shade tolerance is a primary mechanism driving succession in subtropical forests. However, little attention has been given to ontogenetic variation in light tolerance of late succession tree species such as Phoebe bournei. To investigate the differences in adaptive strategies between seedlings and saplings in response to sun and shade, we systematically studied the physiological and morphological leaf plasticity of P. bournei and how these variables are influenced by ontogeny. This study provided experimental evidence that leaf plasticity increases with the ontogeny of juvenile P. bournei adapting to the changing light resources. Investment in leaf construction increased with age and light resources in the evergreen P. bournei, as shown by leaf mass per unit area (LMA). Six-month-old seedlings lacked the adjustment of stomatal conductance (gs) and stomatal density responding to sun and shade. For seedlings, maintaining high gs under sun conditions increased stress risk instead of carbon gain. However, the leaves of 2-year-old saplings accumulated more soluble sugars and showed lower stomatal conductance and higher stomatal density under the sun than under shade conditions. The nonphotochemical quenching of sun leaves increased with plant age, indicating that the photoprotective capacity was enhanced with ontogeny. The leaf plasticity increasing along the ontogeny of juvenile P. bournei may contribute to the adaptation from shade to sun. Our study provides new insights into understanding the influence of ontogeny on shade responses of late succession trees in subtropical forests. [ABSTRACT FROM AUTHOR]

Wet meadows in Germany are of high conservational value with a strong decline over the last centuries. Occasionally, new meadows developed, providing us with the opportunity to compare vegetation and habitat properties of wet meadows with currently similar, but different historical management. We categorized the areas as ancient, old or young, according to the point of establishment and grassland continuity in the last two centuries. Several trends derived from other grassland types proved also to be true for wet meadows like a high diversity of vascular plants and Red List species in long‐term managed grasslands. Old grasslands, established one to two centuries ago, exhibited the highest diversity of vascular plants and bryophytes, indicating additional plants arrived by seeding. We investigated species composition using ordination and indicator species. Ancient grasslands were characterized by plants adapted to wet meadows (Molinietalia) such as Rhinanthus serotinus. Young meadows were marked by plants revealing succession like Carex brizoides or a high productivity. A trend, contrary to other grassland types, was that most habitat properties exhibited no temporal pattern except habitat area and few soil attributes. Altogether, a stepwise intensification from ancient to young meadows was detected that reflects the fast development from traditional to modern agriculture. Including the grassland's history in conservation approaches and adapting the management accordingly will improve restoration attempts. Ancient and old grasslands provided more appropriate species for future wet meadows, whereas young grasslands often need a more intensive land use and would benefit from seeding to develop to species‐rich meadows. [ABSTRACT FROM AUTHOR]

BACKGROUND: Corn is one of the main crops grown globally to produce food for human consumption and animal feed, including raw materials for bioenergy. Effective pest management is critical for the economic viability of corn production. The leafhopper Dalbulus maidis and the diseases transmitted by it have become relevant to corn production. Our study aimed to determine environmental parameters that affect D. maidis populations and the impacts of pathogen dispersion on corn productivity under different rotation systems and sowing seasons. RESULTS: The population density of leafhoppers found in the studied crops was low but capable of establishing the diseases and spreading them widely in the crops. The leafhopper's highest occurrence was in the corn vegetative development stage, and its population peaks were earlier in the corn off‐season. The incidence of maize rayado fino virus and maize bushy stunt phytoplasma were higher in corn off‐season than in the growing season. The incidence of diseases was higher in the final stages of the cultivation cycle. Yield losses were significantly higher for maize bushy stunt phytoplasma and not significant for maize rayado fino virus. CONCLUSION: Our study observed that corn's physiological stage was the main factor influencing D. maidis dynamics. The occurrence of D. maidis at low densities was sufficient to ensure the efficient transmission and dissemination of maize rayado fino virus and maize bushy stunt phytoplasma, which had a higher incidence in the reproductive stage and the corn sowed off‐season. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]