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Several studies have indicated that tri-colored bats (Perimyotis subflavus) are extending their distributional range westward in the United States. Montane and subalpine habitats consist of a mosaic of forest types including Lodgepole Pine woodlands and meadows, which provide an opportunity to study how a newly arriving species—typically associated with lowland riparian systems—is adapting to novel environmental conditions. The objectives of this study are to document Tri-colored Bat activity in these novel habitats and to quantify which factors are influencing activity patterns in habitats and at elevations not previously documented. We surveyed sites in various stages of secondary succession following beetle kill outbreaks using acoustic monitoring and nonparametric multiplicative regression to model habitat activity patterns. Results showed that activity was highest in meadows and early time-since-kill (TSK) forests in the beginning of the survey period and activity increased in late TSK forest habitats at the end of the survey in early August. Tri-colored bats are not restricting their activity to lower-elevational riparian areas in the Colorado foothills but appear to also be using these high-elevation habitats. Careful consideration of misidentification confirms the high likelihood of tri-colored bats at our sites. We hope that this study will support conservation efforts considering the expected US Fish and Wildlife Service Endangered listing for this species. [ABSTRACT FROM AUTHOR]

The structure and diversity of tropical vegetation are shaped by biotic and abiotic factors, which function as environmental filters affecting plant performance on different spatial and temporal scales. We compared soil (Ferrasols and Cambisols) conditions, vegetation structure and leaf traits (e.g., specific leaf area, polyphenols, and chlorophyll contents a/b and in total) in the early, intermediate and late successional stages of a tropical dry forest (TDF) in southeastern Brazil. For this purpose, we measured leaf traits of the most abundant species in the same 18 plots (50 × 20 m/six per successional stage) in 2009 and 2018. Our prediction is that tree species growing in early forests have a greater investment in conservative traits related to chemical defenses and tolerance to desiccation compared to late-stage tree species. We observed contrasting results when comparing the chronosequence differences in leaf traits both in 2009 and 2018 and the temporal changes along this period. Specific leaf area was lower than expected for all successional stages, while polyphenol content increased over time, contrary to other studies in TDFs. These results suggest that contrasting environmental factors such as soil conditions and light availability are responsible of the observed pattern. Total chlorophyll content did not change significantly, while the a/b chlorophyll ratio doubled in all successional stages, contrary to our prediction. Therefore, we suggest that the conservative–acquisitive spectrum in successional gradients of TDFs should be further investigated with time-series data for a better understanding of plant community assemblages. [ABSTRACT FROM AUTHOR]

Questions: Is there a similarity between successional patterns in abandoned fields identified (a) through analysis of differently aged sites examined at one point in time (chronosequence) and (b) those derived from a limited set of semi‐permanent plots? What is the rate of succession on dry and mesic abandoned fields and how is the participation of different functional groups changing during succession? Location: Bohemian Karst, the Czech Republic, Europe. Methods: This study utilises data collected from dry and mesic abandoned fields between 1975 and 2019. A data set of 129 chronosequence vegetation samples (54 dry and 75 mesic plots) and 26 samples from six semi‐permanent plots (11 dry and 15 mesic) with different repetitions were analysed. Plot age (since abandonment) varied from 1 to 91 years for chronosequences and up to 99 years for semi‐permanent data. Moreover, we compared the rate of succession between dry and mesic series using Bray–Curtis dissimilarity. We used a generalised linear mixed model to study the relationship between the cover of different functional groups and the age of abandoned fields. Results: The successional patterns observed on abandoned fields were consistent between the chronosequence and semi‐permanent plots. Both on dry and mesic fields, the early stages of succession transitioned from open annual to perennial herbal vegetation. In mesic fields, the succession led to woodland stands within approximately 25–30 years. Conversely, succession slowed down in dry fields and has persisted for several decades in a stage dominated mostly by perennial graminoids accompanied by scattered shrubs and trees. The trends detected with the chronosequence approach for the different functional groups corresponded to those found in semi‐permanent dry and mesic series plots. Conclusions: The plots using a chronosequence approach can reliably reveal general successional patterns comparable to those obtained from semi‐permanent plots. Observing a higher number of plots at one time may better illustrate the variability of succession at the landscape scale than a detailed, long‐lasting study of a low number of semi‐permanent plots. In the studied area, the dry abandoned fields host a long‐persisting non‐forest state of succession under the current climatic conditions, while succession in mesic abandoned fields continues further towards woodland. [ABSTRACT FROM AUTHOR]

Secondary forests represent a significant proportion of global forest cover, with over 70% of forests in East Asia classified as regenerating. While succession has been studied extensively in temperate systems, trajectories of subtropical succession remain poorly characterized in highly disturbed, urban‐adjacent forests. Investigating the additive beta diversity components of turnover and nestedness may reveal community assembly mechanisms driving secondary succession. The present study investigates plant community assembly along a successional gradient from 7 to 70 years following the onset of succession in secondary subtropical forests in Hong Kong, China. Plant survey data for 28 plots were analysed, generating additive Simpsons turnover and nestedness beta diversity metrics. Dissimilarity matrices were generated and modelled as a function of environmental matrices including forest plant community age (years following onset of secondary succession), inter‐community distance (metres), and soil moisture saturation (%) across three elevational bands using generalized dissimilarity models. Nonmetric multidimensional scaling of plant communities was conducted with Bray–Curtis dissimilarity matrices. Inter‐community distance and successional age differentially influenced plant species turnover between lowland and Montane forest types. Models of nestedness found that plot age and soil moisture saturation were significant drivers of nestedness patterns in plant communities across elevational classes. Turnover represented a higher proportion of Sorensen beta diversity than nestedness, while ANOSIM found significant differentiation between plant communities at different successional stages. Turnover patterns suggest a deterministic model of community assembly, with strong patterns of species replacement between communities at fine spatial scales and successional stages, as well as clear compositional shifts between lowland and montane forest types. NMDS analysis and functional compositional assessments suggested a transition from early successional communities with a high proportion of shrub species, to later successional communities with a higher proportion of tree species, with an increase in species turnover with greater age dissimilarity. [ABSTRACT FROM AUTHOR]

Reconstruction of the anthropogenically transformed environment in order to identify areas of historical environmental management requires a comprehensive analysis of multispectral data. It includes the construction of maps of vegetation indices that take into account spectral and brightness characteristics, and the calculation of textural features that make it possible to divide the survey area into segments with different structures of vegetation cover. The distinctive features of diverse areas of the natural environment are more contrasting when comparing data from different seasons. The survey area included a fragment of the ironworks district of the Pudemsky ironworks, where in the first half of the 19th century intensive deforestation was carried out. Analysis of the seasonal dynamics of the EVI2 vegetation index showed that the area is covered with mixed forest. The difference in the ratio of coniferous and deciduous trees, as well as in the density of their growth, was the rationale for using Haralick features in segmenting multispectral data. Segmentation was carried out using the k-means algorithm with an a priori setting of the number of classes equal to 5. The interpretation of the selected segments, areas characterized by different vegetation textures in the original images, was carried out by using additional information: historical cartographic materials, orthophotomap, multiseasonal maps of the EVI2 vegetation index (June and October). The refinement of the content of the segments was based on the transition matrix, whose analysis demonstrates the similarities and differences in vegetation texture in different classes. Changes in the structure of the segmented image and variations in the configuration and area of individual segments indicate fundamental differences in the vegetation cover of the western and eastern parts of the survey territory, that is, the area of historical cutting areas and the part of the ironworks district that was not subject to intense anthropogenic impact. [ABSTRACT FROM AUTHOR]

Depending on the strength of the relationship between biodiversity and aboveground biomass (AGB), diversity loss could lead to varied declines in carbon storage, compromising the role of forests as carbon sink. This study assesses different factors affecting the diversity–AGB relationship, including small trees (diameter < 7.5 cm) and considering different diversity metrics (Hill numbers), plot sizes (80, 400 and 1000 m2) and successional age categories (8–22, 23–30 and > 60 years). The study compares these relationships across three types of tropical dry forests: deciduous, semi-deciduous, and semi-evergreen. Results reveal the highest deviance values in plots with large trees in the 400 m2 size (d2 = 40.4), decreasing when small trees were included (d2 = 25.8). Higher deviance values show the major contribution of large trees to diversity and AGB of 400 m2 plots, while lower deviance values indicate the high contribution of small trees to diversity but limited contribution to AGB. When analyzing only large trees, deviance decreased with the order of Hill numbers. However, incorporating small trees increased deviance for higher Hill numbers. This is because abundance of small and large trees together has a greater influence on AGB. The diversity–AGB relationship was more prevalent and stronger in the semideciduous forest, which had marked orographic and successional age variation. The strongest diversity–AGB effect occurred in early successional ages, weakening in older stages. Our results show that accuracy in estimating the diversity–AGB relationship varies with plant size, diversity parameters, plot size and forest type. [ABSTRACT FROM AUTHOR]

Post‐disturbance forest management is known to impair biodiversity, including bird communities, but most studies focus on short‐term effects of salvage logging, without recognition of the cumulative, lasting impact of collective post‐disturbance silvicultural practices. We tracked bird community succession in a temperate pine forest from 5 to 19 years after wind disturbance in managed and unmanaged windthrow areas, covering the period from gap creation to early canopy regeneration and comparing it to nearby production forest unaffected by wind disturbance. Bird communities of unmanaged windthrow were consistently the richest in terms of bird abundance and richness. They hosted comparable forest bird diversity to unaffected production stands throughout the study period, as well as a substantial diversity of farmland birds. Managed and unmanaged windthrows followed two distinct successional pathways and did not converge. Despite the bird communities in both windthrows gradually resembling those found in undisturbed forests as the canopy regenerated, each type of windthrow and the unaffected production forest maintained distinct communities until the end of the study. Synthesis and applications. Restraining from any active post‐windthrow management sets bird succession on a distinct pathway, leading to unique and diverse bird communities. We advocate viewing natural disturbances as cost‐effective ecosystem restoration tools, provided no active management is implemented. Furthermore, we advise against using the term ‘salvage logging’ to refer to collective post‐disturbance silvicultural practices, as its varying interpretation may lead to growing confusion as the number of long‐term studies increase. [ABSTRACT FROM AUTHOR]

Summary: Nutrient limitation may constrain the ability of recovering and mature tropical forests to serve as a carbon sink. However, it is unclear to what extent trees can utilize nutrient acquisition strategies – especially root phosphatase enzymes and mycorrhizal symbioses – to overcome low nutrient availability across secondary succession.Using a large‐scale, full factorial nitrogen and phosphorus fertilization experiment of 76 plots along a secondary successional gradient in lowland wet tropical forests of Panama, we tested the extent to which root phosphatase enzyme activity and mycorrhizal colonization are flexible, and if investment shifts over succession, reflective of changing nutrient limitation. We also conducted a meta‐analysis to test how tropical trees adjust these strategies in response to nutrient additions and across succession.We find that tropical trees are dynamic, adjusting investment in strategies – particularly root phosphatase – in response to changing nutrient conditions through succession. These changes reflect a shift from strong nitrogen to weak phosphorus limitation over succession. Our meta‐analysis findings were consistent with our field study; we found more predictable responses of root phosphatase than mycorrhizal colonization to nutrient availability.Our findings suggest that nutrient acquisition strategies respond to nutrient availability and demand in tropical forests, likely critical for alleviating nutrient limitation. [ABSTRACT FROM AUTHOR]

Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies—combinations of growth, mortality and recruitment rates—of the tree species in the community. However, our understanding of demographic diversity in tropical tree species stems almost exclusively from old‐growth forests. Here, we assembled demographic information from repeated forest inventories along chronosequences in two wet (Costa Rica, Panama) and two dry (Mexico) Neotropical forests to assess whether the ranges of demographic strategies present in a community shift across succession. We calculated demographic rates for >500 tree species while controlling for canopy status to compare demographic diversity (i.e., the ranges of demographic strategies) in early successional (0–30 years), late successional (30–120 years) and old‐growth forests using two‐dimensional hypervolumes of pairs of demographic rates. Ranges of demographic strategies largely overlapped across successional stages, and early successional stages already covered the full spectrum of demographic strategies found in old‐growth forests. An exception was a group of species characterized by exceptionally high mortality rates that was confined to early successional stages in the two wet forests. The range of demographic strategies did not expand with succession. Our results suggest that studies of long‐term forest monitoring plots in old‐growth forests, from which most of our current understanding of demographic strategies of tropical tree species is derived, are surprisingly representative of demographic diversity in general, but do not replace the need for further studies in secondary forests. [ABSTRACT FROM AUTHOR]

Full-waveform LiDAR (FWF) offers a promising advantage over other technologies to represent the vertical canopy structure of secondary successions in the Amazon region, as the waveform encapsulates the properties of all elements intercepting the emitted beam. In this study, we investigated modifications in the vertical structure of the Amazonian secondary successions across the vegetation gradient from early to advanced stages of vegetation regrowth. The analysis was performed over two distinct climatic regions (Drier and Wetter), designated using the Maximum Cumulative Water Deficit (MCWD). The study area was covered by 309 sample plots distributed along 25 LiDAR transects. The plots were grouped into three successional stages (early—SS1; intermediate—SS2; advanced—SS3). Mature Forest (MF) was used as a reference of comparison. A total of 14 FWF LiDAR metrics from four categories of analysis (Height, Peaks, Understory and Gaussian Decomposition) were extracted using the Waveform LiDAR for Forestry eXtraction (WoLFeX) software (v1.1.1). In addition to examining the variation in these metrics across different successional stages, we calculated their Relative Recovery (RR) with vegetation regrowth, and evaluated their ability to discriminate successional stages using Random Forest (RF). The results showed significant differences in FWF metrics across the successional stages, and within and between sample plots and regions. The Drier region generally exhibited more pronounced differences between successional stages and lower FWF metric values compared to the Wetter region, mainly in the category of height, peaks, and Gaussian decomposition. Furthermore, the Drier region displayed a lower relative recovery of metrics in the early years of succession, compared to the areas of MF, eventually reaching rates akin to those of the Wetter region as succession progressed. Canopy height metrics such as Waveform distance (WD), and Gaussian Decomposition metrics such as Bottom of canopy (BC), Bottom of canopy distance (BCD) and Canopy distance (CD), related to the height of the lower forest stratum, were the most important attributes in discriminating successional stages in both analyzed regions. However, the Drier region exhibited superior discrimination between successional stages, achieving a weighted F1-score of 0.80 compared to 0.73 in the Wetter region. When comparing the metrics from SS in different stages to MF, our findings underscore that secondary forests achieve substantial relative recovery of FWF metrics within the initial 10 years after land abandonment. Regions with potentially slower relative recovery (e.g., Drier regions) may require longer-term planning to ensure success in providing full potential ecosystem services in the Amazon. [ABSTRACT FROM AUTHOR]

In closed‐canopy systems globally, plants exhibit intense competition for light, prioritizing vertical growth to attain elevated positions within the canopy. Light competition is especially intense in tropical rainforests because of their dense shaded stands, and during forest succession because of concomitant changes in vertical light profiles. We evaluated how the height growth of individual tree differs among forest light strata (canopy, sub‐canopy and understorey) and successional guilds (early, mid‐ and late successional species) during secondary succession in a Mexican rainforest. Fourteen secondary forest stands differing in time since agricultural abandonment (1–25 years) were monitored for seven consecutive years. For each stand and census year we estimated relative light intensity (RLI) for each height and categorized trees into forest light strata: understorey (RLI ≦ 33.3%), sub‐canopy (33.3% ≦ RLI ≦ 66.6%) and canopy (RLI ≧ 66.6%), and into successional guilds based on the literature. We estimated two measures of height growth: absolute height growth (HGabs, cm year−1) calculated as the difference in tree height between two consecutive censuses, and biomass partitioning to height growth (HGbp, in kg kg−1 × 100) calculated as the percentage of total aboveground biomass growth partitioned to height growth. Earlier in succession, trees for all strata had greater HGabs and HGbp, resulting in rapid vertical forest development. HGabs was fastest for canopy trees, followed by sub‐canopy and understorey trees. These differences in HGabs among strata, combined with their inter‐specific variation and continuous recruitment of small individuals, lead to a rapid differentiation in tree sizes and increase stand structural heterogeneity. HGbp was greater for understorey and sub‐canopy trees than for canopy trees, reflecting ontogenetic changes in the light competition strategy from growth to persistence. With succession, both HGabs and HGbp decreased, most strongly for canopy trees, probably because of an increased exposure to drought stress. These successional changes stabilize stand size structure and reduce the rate of development. [ABSTRACT FROM AUTHOR]

The mass of fine (up to 2 mm in diameter) roots of woody species and the patterns of their distribution across the soil profile in post-agricultural forest communities in the middle taiga of Karelia, Russia, have been studied. The characteristics of the forest sites were determined in sampling plots established following conventional procedures. The root mass was determined by the soil monolith method. Analysis showed that young communities developed a greater mass of fine roots compared to older stands. The total root biomass of the top mineral layer of soil was higher than in the forest floor. In most cases, both coniferous and deciduous roots prevailed in the mineral soil layer. A relationship between the fine root mass and the basal area was identified. [ABSTRACT FROM AUTHOR]

Metacommunity theory predicts that the relative importance of regional and local processes structuring communities will change over ecological succession. Determining effects of these processes on taxonomic and evolutionary diversity in spatially structured freshwater habitats of different successional stages may greatly improve understanding of the maintenance of diversity across temporal and spatial scales. In this study, we evaluated crayfish diversity at local and regional scales in pond metacommunities undergoing secondary succession from beaver (Castor canadensis) disturbance. Following theoretical predictions from metacommunity ecology of the increasing importance of local processes over succession, we hypothesised a decline in crayfish local and β diversity over succession from stronger local structuring as the older ponds may provide less suitable habitat than streams.Crayfish species and phylogenetic diversity were evaluated in beaver pond metacommunities and reference headwater streams located in three catchment regions. DNA sequences from the mitochondrial cytochrome oxidase I gene were used to assign crayfish to species for community and phylogenetic diversity tests. Local and β diversity were contrasted across beaver ponds ranging in age from 24 to 70 years and as a function of metacommunity processes.Counter to predictions, local species diversity among streams and the successional stages of ponds categorised by age class (24–39 years; 42–57 years; 60–70 years) did not differ, but community and phylogenetic convergence occurred in the oldest pond ecosystems. Crayfish community composition differed between the youngest and oldest ponds, resulting from higher abundance in the youngest ponds and community convergence in the oldest ponds. The association between community composition and the environment was strongest in streams and decoupled with pond age. In contrast, the correlation between intraspecific haplotype composition and the environment increased over succession. Among the three metacommunities, the regional crayfish species diversity arose from a combination of the temporal and environmental drivers from beaver‐constructed ecosystems and dispersal limitation within catchments.This study represents the first investigation of the taxonomic and phylogenetic diversity response to the successional stages of beaver pond metacommunities. The detection of differential crayfish composition and haplotype sorting to pond age suggests a role for local structuring and further indicates that future studies should acknowledge succession in shaping species diversity at local and regional scales. Dispersal limitation within catchment regions probably contributes to the evolution of crayfish species diversity in metacommunities and the overall maintenance of biodiversity.The results support a transition in community and freshwater ecology from a recent emphasis on spatial processes towards the integration of temporal drivers to better identify regulators of taxonomic and phylogenetic diversity across scales. [ABSTRACT FROM AUTHOR]

Background and aims: The most substantial global land use change is the transformation of native ecosystems into agroecosystems, leading to loss of biodiversity and reduction of ecosystem services. Potentially, these degraded systems could be restored from their soil seed bank. Our aim was to assess species richness and density of the soil seed bank along a structural complexity gradient in agroecosystems and Espinal forest fragments. Furthermore, we compared species composition between the soil seed bank and established vegetation of the reference system to explore its potential for regeneration of native plant communities. M&M: A structural complexity gradient was created from vegetation and soil structural variables from plots with different land uses to analyze seed bank variables. Results: The highest richness was recorded in the pasture soil seed bank, followed by the forests. The highest density and similarity to the established vegetation of the reference system was registered in the forests. Herbaceous species predominated in all plots. With the exception of Celtis tala, seeds of dominant woody species from the reference system were not observed. Conclusions: The pasture seed bank may be particularly relevant in the early stage of native forest restoration, especially if the aim is to reduce costs. However, the contribution of the seed bank to Espinal forests recovery in short to medium term is limited due to its low similarity to reference system. [ABSTRACT FROM AUTHOR]

Secondary forests represent an increasing proportion of global forest cover and offer a range of ecosystem services that are integral to environmental policy targets. Highly disturbed landscapes with temporal records of forest plant community composition offer key insights into the processes that shape plant communities as forests undergo secondary succession. We investigated patterns of plant community phylogenetic structure and phylogenetic beta diversity. Mean pairwise distance (MPD) and Mean Nearest Taxon Distance (MNTD) metrics were determined between co-occurring species within plant communities, in addition to phylogenetic beta diversity metrics relative to null models of random phylogenetic assembly. MPD and MNTD were compared between elevational and successional classes and modelled as products of intercommunity distance (metres) and forest community age (years). Phylogenetic nonmetric multidimensional scaling explored phylogenetic community structure between lowland and montane forest type in Hong Kong. We found that plant communities in secondary forests in Hong Kong exhibited patterns of increased basal phylogenetic clustering with increasing community elevation, while phylogenetic turnover was influenced by spatial and successional factors in lowland and montane forest. Our findings indicate differential community assembly in lowland compared to montane forest type in Hong Kong, as well as evidence for barriers to plant dispersal in secondary forest communities due to patterns of spatial phylogenetic clustering. Plant communities in montane forests were found to be phylogenetically distinct from lowland forest plant communities. Patterns of spatial phylogenetic clustering may suggest significant dispersal or post-dispersal processes causing the clustering of related species at fine spatial scales, while phylogenetic turnover with increasing successional age may indicate compositional changes during the process of passive forest regeneration. Collectively, these results emphasize the need to investigate active pathways for rewilding dispersal limited late successional forest tree species in Hong Kong.

Abstract Secondary forests represent a significant proportion of global forest cover, with over 70% of forests in East Asia classified as regenerating. While succession has been studied extensively in temperate systems, trajectories of subtropical succession remain poorly characterized in highly disturbed, urban‐adjacent forests. Investigating the additive beta diversity components of turnover and nestedness may reveal community assembly mechanisms driving secondary succession. The present study investigates plant community assembly along a successional gradient from 7 to 70 years following the onset of succession in secondary subtropical forests in Hong Kong, China. Plant survey data for 28 plots were analysed, generating additive Simpsons turnover and nestedness beta diversity metrics. Dissimilarity matrices were generated and modelled as a function of environmental matrices including forest plant community age (years following onset of secondary succession), inter‐community distance (metres), and soil moisture saturation (%) across three elevational bands using generalized dissimilarity models. Nonmetric multidimensional scaling of plant communities was conducted with Bray–Curtis dissimilarity matrices. Inter‐community distance and successional age differentially influenced plant species turnover between lowland and Montane forest types. Models of nestedness found that plot age and soil moisture saturation were significant drivers of nestedness patterns in plant communities across elevational classes. Turnover represented a higher proportion of Sorensen beta diversity than nestedness, while ANOSIM found significant differentiation between plant communities at different successional stages. Turnover patterns suggest a deterministic model of community assembly, with strong patterns of species replacement between communities at fine spatial scales and successional stages, as well as clear compositional shifts between lowland and montane forest types. NMDS analysis and functional compositional assessments suggested a transition from early successional communities with a high proportion of shrub species, to later successional communities with a higher proportion of tree species, with an increase in species turnover with greater age dissimilarity.

Biodiversity loss is one on global environmental issues facing humanity. Intensive use of natural resources has led to degradation of landscapes and reduction of the species diversity of plant communities. Therefore, finding natural solutions to overcome these challenges is an urgent issue. The purpose of the study was to investigate the dynamics of floral composition and coenotic structure of herbaceous plant communities in an organic cherry orchard for the sustainable functioning of the agricultural landscape. The dynamics of the coenotic composition of natural grasses of vegetation cover in the organic cherry orchard was studied during 2013-2020 in the arid conditions of the Southern Steppe of Ukraine on low-humus sandy loam soils. Morphological, ecological, and geographical methods were used to investigate the species diversity of flora in an organic garden. The composition of herbaceous plant communities was estimated using conbentional geobotanic description methods. The results of the study of the species composition and coenotic structure of plant communities of grass cover in an organic sweet cherry orchard are presented. Grassing of the garden with natural grasses has led to the enrichment of agricultural landscapes with useful species that are important components of sustainable agricultural systems and can perform ecological services. Colonisation of the grass cover by invasive and quarantine species was not observed due to natural processes of demutation succession and the use of moderate four-fold mowing of plants during the growing season (to a height of 15- 20 cm). As part of herbal plant communities in the 8th year of research, all species were useful, had medicinal properties, and served as a food base. The natural grasses in an organic sweet cherry orchard are a resource of biomass and biodiversity. Phytocoenotic analysis of the grass cover in the organic cherry orchard will allow substantiating and proposing principles for predicting the development of plant communities to optimise their structure, improve quality, and maintain biodiversity

The changes in the biotope and in the spectrum of ecological coenotic groups of herb and dwarf shrub tiers of vegetation have been monitored over ten years following the clearcutting of the Piceetum myrtillosum (bilberry-rich spruce forest) considering on-site retention of aspen (Populus tremula L.) in the Babaevsky District of Vologda Oblast. During the first years after clearcutting, the vegetation cover is unstable, sparse, is characterized by pronounced species changes. The diverse ecotopes resulting from clearcutting contribute to the rapid emergence of new plants, including meadow and swamp species, in disturbed communities. Subsequently, tree tier with the dominance of small-leaved trees forms gradually at after clearcutting site. Additionally, the abundance of the shade-tolerant species increases, while that of the meadow species decreases.

Aims: Tundra communities are known for their harsh environmental conditions and tundra is one of the most vulnerable biomes on Earth. Restoring these unique communities after anthropogenic impact is crucial for the sustainable development of northern regions. The objective of this study was to evaluate the recovery of subarctic tundra after long‐term agricultural use. Location: Subarctic zone, European northeast, Vorkuta district, Komi Republic, Russia. Methods: In the latter half of the twentieth century, large areas of tundra were plowed and cultivated with cereals to be used as fodder in livestock farms. These areas were subsequently abandoned (1990–2000) and the stage of natural recovery began. From 1960 to 2017 one of these plant communities was regularly assessed and we used these data, along with data from a reference tundra community, to examine changes in community assembly. We evaluated biodiversity indices, functional diversity using various plant traits and phylogenetic diversity. Results: Agricultural management in tundra areas has led to the development of a meadow community that differs significantly from the typical tundra found in similar landscapes. The highest level of meadow biodiversity was observed under moderate anthropogenic pressure. The most significant changes in plant community assembly were observed after withdrawal from agricultural use. The average plant height, leaf area, and leaf dry matter content increased, while the average specific leaf area and leaf nitrogen content decreased. The functional and phylogenetic clustering was replaced by overdispersion. Conclusions: Over the 20‐year period following the cessation of agricultural use, we observed a decrease in the vitality of cultivated cereals and overall biodiversity. However, there was a redistribution of species abundance rather than a complete change in species composition. Deciduous and evergreen shrubs have not become introduced in sufficient abundance to transform the artificial meadow into the typical subarctic willow–shrub tundra. This is a fundamental difference between abandoned agricultural lands of the tundra zone and those of more southern regions, which are rapidly overgrown with pioneer tree or shrub species. [ABSTRACT FROM AUTHOR]

Background and aims: There is still limited knowledge regarding the dynamics of soil microbial community structures and functional groups during forest secondary succession after rubber monocultures (RP) abandonment. Methods: Bacterial and fungal communities and functions were investigated for the soil from six forest stands with three replicate plots. Selected stands included an RP, four spontaneous secondary forest stands that formed after RP abandonment at 1 (SF_1), 10 (SF_10), 20 (SF_20), and 40 (SF_40) years, as well as a primary forest (PF, approximately 100 years). Results: After RP abandonment, the alpha-diversity metrics of soil microbial communities increased during the first 40 years of succession but decreased in PF. The biomarkers Proteobacteria and Mortierellomycota increased significantly (P < 0.05) by 84% and 633% in PF, respectively, while Firmicutes showed a significant decrease of 89% in comparison with SF_1. Secondary succession increased the relative abundance of bacterial functional groups related to carbon cycling and fungal functional groups (especially ericoid mycorrhizal). Soil pH was the main edaphic factor in shaping microbial communities and functions. In addition, soil moisture and seasonal variations had direct impacts on fungal communities and bacterial functions. Conclusions: Collectively, these findings suggest that different successional trajectories occur in bacteria and fungi, owing to their divergent responses to the changes in season, soil moisture, and nutrients. Specifically, the frequent shifts in bacterial dominant phyla during succession, as well as the increased susceptibility of diversity and functional groups to season, indicate that bacteria respond more quickly to disturbances compared to fungi. [ABSTRACT FROM AUTHOR]

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

Biodiversity loss is one on global environmental issues facing humanity. Intensive use of natural resources has led to degradation of landscapes and reduction of the species diversity of plant communities. Therefore, finding natural solutions to overcome these challenges is an urgent issue. The purpose of the study was to investigate the dynamics of floral composition and coenotic structure of herbaceous plant communities in an organic cherry orchard for the sustainable functioning of the agricultural landscape. The dynamics of the coenotic composition of natural grasses of vegetation cover in the organic cherry orchard was studied during 2013-2020 in the arid conditions of the Southern Steppe of Ukraine on low-humus sandy loam soils. Morphological, ecological, and geographical methods were used to investigate the species diversity of flora in an organic garden. The composition of herbaceous plant communities was estimated using conbentional geobotanic description methods. The results of the study of the species composition and coenotic structure of plant communities of grass cover in an organic sweet cherry orchard are presented. Grassing of the garden with natural grasses has led to the enrichment of agricultural landscapes with useful species that are important components of sustainable agricultural systems and can perform ecological services. Colonisation of the grass cover by invasive and quarantine species was not observed due to natural processes of demutation succession and the use of moderate four-fold mowing of plants during the growing season (to a height of 15-20 cm). As part of herbal plant communities in the 8th year of research, all species were useful, had medicinal properties, and served as a food base. The natural grasses in an organic sweet cherry orchard are a resource of biomass and biodiversity. Phytocoenotic analysis of the grass cover in the organic cherry orchard will allow substantiating and proposing principles for predicting the development of plant communities to optimise their structure, improve quality, and maintain biodiversity. [ABSTRACT FROM AUTHOR]

Questions: Agricultural expansion is one of the dominant drivers of forest and biodiversity loss, and shifting cultivation is the most widely used form of agriculture in many tropical forest regions. Where forests have been cleared, they have the potential to recover once the land is abandoned. However, legacies of land use are often overlooked in successional studies, and a deeper understanding of this legacy effect is needed to define efficient restoration practices using natural or assisted regeneration. Here, we analysed how land‐use history affects soil properties and early succession on abandoned agricultural fields in two contrasting Mexican socio‐ecological systems. Location: Mexico, Oaxaca and Chiapas. Methods: We sampled soil and monitored vegetation for 2 years after agricultural abandonment, and interviewed landowners about their land‐use practices. Results: Land‐use practices were clearly influenced by landowners' social context (residence time, rural or urban origin), and topography and soil type also constrained or facilitated land‐use practices. Soil characteristics were strongly affected by three land‐use practices: mechanical tillage decreased soil N and K; frequent herbicide and pesticide use increased N and K; and for pasture systems, stocking density increased soil bulk density and decreased pH and N. High‐intensity land management practices, specifically use of machinery, had the highest impact on early forest succession. When machinery was not used, the frequency of land‐use practices, particularly weeding frequency, is the main factor influencing tree cover and sapling diversity. Conclusions: To facilitate post‐agricultural forest recovery, we recommend restoration efforts using natural regeneration in areas with low previous land‐use intensity and frequency. [ABSTRACT FROM AUTHOR]

Aims: Herbaceous plant cover can be used to inhibit tree encroachment in many managed and semi‐natural grasslands. Ideally, herbaceous seed mixtures should reduce the establishment and growth of many invading tree species over several years. Theory predicts that invasion resistance can be maximized by both: (a) increasing the diversity (taxonomic and/or functional) of resident seed mixtures, and (b) including species that are especially efficient at blocking further colonizers. We established an experiment in a regularly mown old field within a deciduous forest region in southeastern Canada. Our overall goal was to examine the relative contribution of old field community composition and diversity (taxonomic and functional) to resistance against encroachment by two undesirable native tree species over time. Location: Varennes, southern Québec, Canada (45°37′01.24″ N, 73°23′03.57″ W). Methods: We tested our hypotheses by seeding experimental plots with different levels of taxonomic diversity (from one to nine species) and functional group richness (grasses, legumes, and forbs). Our herbaceous species comprised four native species and five introduced and naturalized species. We then seeded the plots with two model tree colonizers, Acer rubrum and Betula populifolia, during three consecutive years. We also transplanted seedlings of Acer and Betula to determine the effect of herbaceous diversity on post‐emergence growth and seedling survival. Results: Overall, herbaceous species identity (presence and absence) better predicted the resistance of resident herbaceous seed mixtures to tree encroachment than the other diversity measures assessed in our study. Fast‐growing herbaceous species, such as Lolium, substantially inhibit resistance to woody encroachment in the first year. Achillea millefolium and Solidago canadensis were by far the most efficient in blocking tree seedling establishment and growth, particularly during the second and third years. These effects highlight the potential for a combination of fast‐growing species, along with slower‐growing but highly inhibitive species, as a way to limit tree encroachment in real field applications. Functional group richness was a poor predictor of tree encroachment. Species richness reduced tree encroachment, especially when considering a multidimensional tree encroachment index integrating all aspects of tree establishment and growth over the three years of our experiment. Conclusions: Seeding highly inhibiting herbaceous species is the most efficient approach against specific tree invaders. However, it is difficult to implement in practice because it relies on a priori knowledge of the species' inhibitory effects. In the absence of this knowledge, the taxonomic richness of seed mixtures should be increased to prevent tree encroachment. [ABSTRACT FROM AUTHOR]

Determining which species to utilize for the artificial restoration of subtropical secondary forests has become a focal point in forestry and ecology. To compare the effects of the subtropical secondary forest artificial restoration model on soil microbial nutrient acquisition and limitation, we examined secondary forests (CKs), evergreen coniferous forests (GCPs), evergreen coniferous mixed broad-leaved forests (GCBMs), evergreen mixed broad-leaved forests (GBMs), and natural deciduous broad-leaved mixed forests (DBMs) as research subjects. Among them, GCPs, GCBMs, and GBMs were dominated by the species of the early, middle, and climax stages of subtropical forest succession, respectively. The activities and stoichiometry of β-1,4-glucosidase (BG), β-1,4-N-acetylglucosaminidase (NAG), leucine aminopeptidase (LAP), and acid phosphatase (ACP) in the topsoil were analyzed. The results showed that the forest type significantly affects the activities of BG and LAP rather than NAG or ACP. The BG activity in DBMs was the lowest, while the LAP activity in CKs was significantly higher than that in plantations. Furthermore, the nutrient limitation of microbes was quantitatively analyzed by using the vector analysis of enzyme stoichiometry. The soil microbes in the study area were co-limited by C and P, and the nutrient limitation was in the order of C > P > N. Among the forests, the enzyme stoichiometric ratios in GCPs and DBMs were closest to 1:1:1. From CKs to GBMs, the microbial C limitation was increased, while the P limitation was decreased. The C limitation in DBMs was slightly lower than that in CKs. Overall, the P limitation in evergreen plantations was less than that in CKs. The soil bulk density, C/P, and N/P significantly influenced enzyme activities and stoichiometry. These results suggest that the artificial restoration of subtropical forests using evergreen species alleviated P limitation, while using deciduous broad-leaved species offered potential for alleviating microbial C limitation. Compared with evergreen broad-leaved species, employing pioneer and mid-successional or deciduous broad-leaved species can better achieve balanced microbial nutrient requirements. [ABSTRACT FROM AUTHOR]

Across ecology, and particularly within microbial ecology, there is limited understanding how the generation and maintenance of diversity. Although recent work has shown that both local assembly processes and species pools are important in structuring microbial communities, the relative contributions of these mechanisms remain an important question. Moreover, the roles of local assembly processes and species pools are drastically different when explicitly considering the potential for saturation or unsaturation, yet this issue is rarely addressed. Thus, we established a conceptual model that incorporated saturation theory into the microbiological domain to advance the understanding of mechanisms controlling soil bacterial diversity during forest secondary succession. Conceptual model hypotheses were tested by coupling soil bacterial diversity, local assembly processes and species pools using six different forest successional chronosequences distributed across multiple climate zones. Consistent with the unsaturated case proposed in our conceptual framework, we found that species pool consistently affected α‐diversity, even while local assembly processes on local richness operate. In contrast, the effects of species pool on β‐diversity disappeared once local assembly processes were taken into account, and changes in environmental conditions during secondary succession led to shifts in β‐diversity through mediation of the strength of heterogeneous selection. Overall, this study represents one of the first to demonstrate that most local bacterial communities might be unsaturated, where the effect of species pool on α‐diversity is robust to the consideration of multiple environmental influences, but β‐diversity is constrained by environmental selection. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms controlling community diversity is a central, topic in ecology, particularly in microbial ecology. Although species pools and local assembly processes are believed to play non‐negligible roles in shaping the within‐community (α) and among‐community (β) diversity of microbial communities, their relative importance as succession progresses remains elusive. Moreover, the roles of both mechanisms on diversity might be strikingly different depending on whether saturation is considered or not, yet this issue is far less appreciated. To investigate the mechanisms underlying soil fungal α and β diversity during secondary succession, soil samples were collected from six different successional chronosequences including 293 plots across different climatic zones. We found that in all chronosequences, increases in α diversity tracked increases in species pool size, showing a linear unsaturated relationship, despite β diversity not always co‐varied with species pool size. After correcting for differences in species pools, environmental selection appeared to explain variation in β diversity rather than variation in α diversity. Further piecewise structural equation modeling demonstrated that the species pool was more important in α diversity change than environmental selection in most of the cases, whereas the importance of heterogeneous selection outweighed species pool in shaping β diversity. Overall, these findings represent one of the first to demonstrate that most local fungal communities might be unsaturated, where the relative importance of species pool and environmental selection for variations in α and β diversity during secondary succession differs markedly. Considering the mechanisms controlling diversity will be distinctly different under unsaturation or saturation, we set up an extended conceptual model combined with saturation theory to broaden the perspective to comprehensively understand mechanisms causing biodiversity change during secondary succession in unsaturated/saturated communities, intending to enhance our ability to predict soil fungal diversity in the future. [ABSTRACT FROM AUTHOR]

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Life forms are key to understand the changes in species composition and vegetation types in space and with succession over time. We asked how life forms from dry and wet regions differ in their leaf traits and trait hyperspace (i.e. trait variation) in early tropical forest succession on abandoned agricultural fields.We compared 324 early successional species from six life forms (herbs, grasses, vines, lianas, shrubs and trees) that occur in the first 5 years of succession on abandoned fields in Ghanaian wet and drought deciduous tropical forests. We measured 12 leaf traits that are important for carbon, water and nutrient use.A principal component analysis showed that 46% of trait variation is captured by a two‐dimensional spectrum of plant form and function: a leaf economics spectrum underpinning fast‐slow growth strategies, and a leaf size spectrum related to plant size and heat balance, which underlie species sorting along environmental gradients in space and time (during succession). Herbaceous and woody life forms had different leaf economics strategies: herbaceous species had more acquisitive trait values (e.g. higher leaf nutrient concentrations) that increase resource capture and use efficiency whereas woody species had more conservative trait values (e.g. higher leaf mass per area) that increase resource conservation. Regardless of life forms, dry forest species and deciduous species had more acquisitive trait values than wet forest species and evergreen species as they maximize their growth during the shorter growing season. The trait hyperspace was larger for woody life forms especially in wet forests.Synthesis. Herbaceous species had 'faster' leaf economics trait values and, hence, rapid carbon gain, explaining their success earlier in succession. In contrast, woody species had 'slower' resource conservation trait values that increase persistence, thus explaining their success later in succession. Deciduous species especially in a dry region had higher leaf nitrogen and phosphorus concentration to attain faster carbon gain to cope with a seasonally harsh environment. The trait hyperspace was generally smaller in the dry forest, as there are more deciduous species, and as a result, there is less variation in leaf lifespan and associated traits. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Irazú volcano is one of the highest peaks in Costa Rica; it constitutes one of the few sites with the plant association known as montane and sub-paramo. The research aimed to characterize the structure and composition of this ecosystem considering two altitudinal floors (montane and subpáramo). Three 1000 m² plots per forest type were established, in which botanical identification was developed, and diameter and total height were measured. In both forests, the diameter distributions were adjusted to the different forest models with a basal area of 31.68 m² ha¹ in montane forest and 4.67 m² ha¹ in subpáramo forest. Regarding the vertical structure, the montane forest reached a maximum height of 21 m with three well-defined strata; on the other hand, the subpáramo reached 8 m and did not differentiate strata. Regarding the diversity analysis, it was determined that both forests have significant differences; the montane forest reported 20 species, while the subpáramo only had six species. Comarostaphylis arbutoides is the most important species for both communities. The most important conclusion is that the study area can be considered an altitudinal island; it represents a site of high value for the conservation and research of the sub-paramo plant community. The structure is straightforward in species, its area is minimal, and it is very vulnerable to volcanic events, which shows its value for conservation and study. [ABSTRACT FROM AUTHOR]

Soil ectomycorrhizal and saprotrophic fungi play pivotal roles in plant performance and ecosystem functioning. However, the effects of forest secondary succession on their abundance, diversity, and community structure remain unclear. We examined ectomycorrhizal and saprotrophic communities (Illumina Sequencing and FUNGuild database) in five forest secondary successional stages (20-, 32-, 47-, 61-, and > 200-year-old stands). Our results showed that ectomycorrhizal and saprotrophic communities varied with successional stages. The relative abundance of ectomycorrhizal fungi decreased from early to late stages but the relative abundance of saprotrophic fungi increased. In contrast to the abundance, diversity of ectomycorrhizal fungal communities increased with the succession, while saprotrophic fungal diversity dropped in the early successional stages and recovered later stages. Furthermore, there were significant differences in the community structure of ectomycorrhizal and saprotrophic fungi among different successional stages, and the main driving factor (tree productivity) of the shifts in two community structures was similar. Interestingly, there was a significant negative correlation between the variations in relative abundance and community structure of ectomycorrhizal and saprotrophic fungi along the secondary succession, which implied the interactions between ectomycorrhizal and saprotrophic fungi during the successional process. These results indicated that the secondary succession might not only increase decompositions of organic matter by increasing saprotrophic fungal abundance, but also stimulate the return of saprotrophic fungal diversity, which may be beneficial to plant function and ecosystem stability. [ABSTRACT FROM AUTHOR]

This study analyzes floristic and vegetation structure changes during forest succession after disturbances caused by small-scale gold mining in Madre de Dios (Peru). We compared the floristic and vegetation structure of a reference forest against three sites with different periods of abandonment after mining (5, 11 and 23-years). Three 20 × 60 m plots were defined on each site, and all tree species with a DBH >1 cm within the plots were inventoried. To evaluate species diversity and similarity, the Importance Value, effective numbers of species (0D, 1D, and 2D), and Chao-Jaccard similarity index were calculated. We used the Nonmetric multidimensional scaling for similarity ordination and the PERMANOVA test to evaluate differences in floristic composition. We recorded 129 tree species in the study areas and statistically significant differences between initial and intermediate stages were observed regarding floristic composition, basal area, height, and DBH. The transition from the initial successional stage to the reference forest produces an increase in basal area, species diversity, and floristic similarity. The 23-year-old stand had more species in common with the 11-year-old stand than the reference forest. Our results showed a high proportion of pioneer species and anemochory dispersal syndrome in the initial successional stages, but they decreased in later stages of the chronosequence. The floristic and structural attributes of forests throughout the chronosequence showed a fast recovery during secondary succession. After 23 years, the recovery of tree species density was 77 % of reference forest, while the relative recovery of species composition was much slower, on average 23 %. These results provide essential information to guide the selection of suitable species in ecological restoration projects after abandonment. Implementing forest restoration strategies based on reliable information to accelerate the process of vegetation succession is critical for recuperating areas degraded by gold mining at the Peruvian Amazon.

Full-waveform LiDAR (FWF) offers a promising advantage over other technologies to represent the vertical canopy structure of secondary successions in the Amazon region, as the waveform encapsulates the properties of all elements intercepting the emitted beam. In this study, we investigated modifications in the vertical structure of the Amazonian secondary successions across the vegetation gradient from early to advanced stages of vegetation regrowth. The analysis was performed over two distinct climatic regions (Drier and Wetter), designated using the Maximum Cumulative Water Deficit (MCWD). The study area was covered by 309 sample plots distributed along 25 LiDAR transects. The plots were grouped into three successional stages (early—SS1; intermediate—SS2; advanced—SS3). Mature Forest (MF) was used as a reference of comparison. A total of 14 FWF LiDAR metrics from four categories of analysis (Height, Peaks, Understory and Gaussian Decomposition) were extracted using the Waveform LiDAR for Forestry eXtraction (WoLFeX) software (v1.1.1). In addition to examining the variation in these metrics across different successional stages, we calculated their Relative Recovery (RR) with vegetation regrowth, and evaluated their ability to discriminate successional stages using Random Forest (RF). The results showed significant differences in FWF metrics across the successional stages, and within and between sample plots and regions. The Drier region generally exhibited more pronounced differences between successional stages and lower FWF metric values compared to the Wetter region, mainly in the category of height, peaks, and Gaussian decomposition. Furthermore, the Drier region displayed a lower relative recovery of metrics in the early years of succession, compared to the areas of MF, eventually reaching rates akin to those of the Wetter region as succession progressed. Canopy height metrics such as Waveform distance (WD), and Gaussian Decomposition metrics such as Bottom of canopy (BC), Bottom of canopy distance (BCD) and Canopy distance (CD), related to the height of the lower forest stratum, were the most important attributes in discriminating successional stages in both analyzed regions. However, the Drier region exhibited superior discrimination between successional stages, achieving a weighted F1-score of 0.80 compared to 0.73 in the Wetter region. When comparing the metrics from SS in different stages to MF, our findings underscore that secondary forests achieve substantial relative recovery of FWF metrics within the initial 10 years after land abandonment. Regions with potentially slower relative recovery (e.g., Drier regions) may require longer-term planning to ensure success in providing full potential ecosystem services in the Amazon.

The structure and diversity of plant communities respond to changes in landscape structure and vary with spatial scale, stand age and plant size. Therefore, it is important to identify the scale (grain size and extent) at which secondary forest attributes of large and/or small plants and landscape structure are more closely associated. We performed multi-scale analyses in which different grain sizes and extents were assessed to determine the most appropriate spatial scale for assessing the association of large/small tree aboveground biomass and species richness with successional age and landscape structure using regression analysis. AGB and species richness were more strongly associated with landscape structure when large grain sizes (500 m2) were used, with R2 values between 0.31 and 0.43. Variation in AGB and species richness was explained primarily by successional age and landscape structure, respectively. At large extents, successional age was related to the AGB of large trees (R2 = 0.43); at intermediate extents, landscape structure was related to the species richness of large trees (R2 = 0.31). The approach and results of this study may facilitate the identification of appropriate areas and scales for the maintenance or restoration of tree diversity, carbon storage, and the provision of ecosystem services in tropical dry forests.

Abstract Background Soil microbiomes are increasingly acknowledged to affect plant functioning. Research in molecular model species Arabidopsis thaliana has given detailed insights of such plant-microbiome interactions. However, the circumstances under which natural A. thaliana plants have been studied so far might represent only a subset of A. thaliana’s full ecological context and potential biotic diversity of its root-associated microbiome. Results We collected A. thaliana root-associated soils from a secondary succession gradient covering 40 years of land abandonment. All field sites were situated on the same parent soil material and in the same climatic region. By sequencing the bacterial and fungal communities and soil abiotic analysis we discovered differences in both the biotic and abiotic composition of the root-associated soil of A. thaliana and these differences are in accordance with the successional class of the field sites. As the studied sites all have been under (former) agricultural use, and a climatic cline is absent, we were able to reveal a more complete variety of ecological contexts A. thaliana can appear and sustain in. Conclusions Our findings lead to the conclusion that although A. thaliana is considered a pioneer plant species and previously almost exclusively studied in early succession and disturbed sites, plants can successfully establish in soils which have experienced years of ecological development. Thereby, A. thaliana can be exposed to a much wider variation in soil ecological context than is currently presumed. This knowledge opens up new opportunities to enhance our understanding of causal plant-microbiome interactions as A. thaliana cannot only grow in contrasting soil biotic and abiotic conditions along a latitudinal gradient, but also when those conditions vary along a secondary succession gradient. Future research could give insights in important plant factors to grow in more ecologically complex later-secondary succession soils, which is an impending direction of our current agricultural systems.

The development of indices of ecosystem quality makes it possible to obtain robust information with less human and material effort. These indices are especially useful for assessing the quality of ecosystems disturbed by anthropogenic impact since they can inform management decisions designed to recover their functionality. The abandonment of agricultural activity is a major environmental challenge, and it is important to understand its consequences on ecosystem functioning. The main objective of this work was to develop a robust quality index of abandoned agrosystems based on detailed information on soil properties and structure and the composition of the vegetation. A chronosequence was built of abandoned vineyards over the last 60 years. Seventeen soil physical-chemical properties and ten enzymatic activities related to the cycles of C, N, P and S were determined in 21 plots along the chronosequence. Total vegetation cover, cover of cryptograms and phanerogams and cover of plant functional groups was also recorded. The main factors involved in the quality of the ecosystem were detected by means of network analyses based on these variables. Models were then developed to calculate ecosystem quality indices. Our results showed how the evolution of soil properties occurred simultaneously with variations in the composition and structure of the vegetation. The major factors that determined the functionality of abandoned agrosystems were the quantity and quality of soil organic matter (high TOC and WHN) and the lesser abundance of sulphur accumulator plants. The ecosystem quality index model found to be the most robust was the index with integration by weights and non-linear scores, which followed a sigmoid pattern throughout the chronosequence. Our results highlight the importance of developing robust quality indices based on an interdisciplinary approach.

Reservoirs are fundamental for human well-being but can cause landscape changes (e.g., habitat fragmentation and loss), altering biodiversity and ecosystem services. However, we know little about reservoir long-term effects on bird communities of tropical rainforests at different temporal scales. We assessed species richness and composition changes in four consecutive periods in a reservoir area in the Colombian Tropical Andes. After 20 years of monitoring avifauna within the reservoir, we recorded 360 bird species along with 47 local extinction and 184 colonization events. We found that species richness increased by 42% during the first 11 years after reservoir establishment. After that, changes in species bird composition were largely explained by species turnover. Eighty-two percent of the expected species in the region were recorded within the reservoir area. Also, forests surrounding the reservoir are a habitat for several threatened bird species. Bird community changes observed can be explained by secondary succession, changes in vegetation cover (i.e., increase in forest area), the transformation of aquatic ecosystems, forest protection, and restoration programs focused on biodiversity conservation. Long-term systematic bird sampling in tropical forests is key to understanding biodiversity dynamics and the effectiveness of conservation actions.

Determining litterfall and corresponding element fluxes is valuable in understanding productivity and biogeochemical cycling in floristically distinct secondary successional zones. Secondary-growth forests form a major portion of the cool-temperate forests of South Korea following decades of severe disturbance and intensive rehabilitation efforts. This study monitored the total and fraction-specific litterfall mass, element flux, and nutrient use efficiency patterns of a secondary-growth broadleaf deciduous forest (hereafter, BDFA) and compared these values in forests with contrasting sub-canopy compositions (BDFB) and with coniferous evergreen forests (CEF). Mean annual total litterfall mass was uniform across stands at a range of 871.5 g m−2 yr−1 to 990.2 g m−2 yr−1. Litterfall mass of seed, bark, and miscellaneous fractions varied per stand (p Ca > K > Mg > P, whereas NUE followed a reverse sequence. NUE in CEF was higher than BDFA and BDFB for all macronutrients, reflecting the distinct biomass allocation and nutrient utilization strategies between conifers and broadleaves. In temperate secondary-growth forests, nutrient cycling via litterfall is substantiated primarily by litterfall quantity and secondarily by litter element concentration. Our findings have important implications for elucidating forest litter ecology and improving sustainable management practices in secondary successional forests.

The soil fungal community plays an important role in forest ecosystems and is crucially influenced by forest secondary succession. However, the driving factors of fungal community and function during temperate forest succession and their potential impact on succession processes remain poorly understood. In this study, we investigated the dynamics of the soil fungal community in three temperate forest secondary successional stages (shrublands, coniferous forests, and deciduous broad‐leaved forests) using high‐throughput DNA sequencing coupled with functional prediction via the FUNGuild database. We found that fungal community richness, α‐diversity, and evenness decreased significantly during the succession process. Soil available phosphorus and nitrate nitrogen decreased significantly after initial succession occurred, and redundancy analysis showed that both were significant predictors of soil fungal community structure. Among functional groups, fungal saprotrophs and pathotrophs represented by plant pathogens were significantly enriched in the early‐successional stage, while fungal symbiotrophs represented by ectomycorrhiza were significantly increased in the late‐successional stage. The abundance of both saprotroph and pathotroph fungal guilds was positively correlated with soil nitrate nitrogen and available phosphorus content. Ectomycorrhizal fungi were negatively correlated with nitrate nitrogen and available phosphorus content and positively correlated with ammonium nitrogen content. These results indicate that the dynamics of fungal community and function reflected the changes in nitrogen and phosphorus availability caused by the secondary succession in temperate forests. The fungal plant pathogen accumulated in the early‐successional stage and ectomycorrhizal fungi accumulated in the late‐successional stage may have a potential role in promoting forest succession. These findings contribute to a better understanding of the response of soil fungal communities to secondary forest succession and highlight the importance of fungal communities during the successional process. [ABSTRACT FROM AUTHOR]

The composition and stability of soil aggregates are important characteristics for evaluating soil health. The objective of this study was to explore the effects of different restoration modes and secondary succession sequences of Korean pine on the stability of forest soil aggregates after clear cutting and their causes. The stability and composition of soil aggregates in 0–10 cm, 10–20 cm, and 20–40 cm were analyzed in four natural forests in the secondary succession sequence and a Pinus koraiensis plantation in the clear-cutting area of Liangshui National Nature Reserve, and the effects of forest community characteristics and cementing materials on these aggregates were explored. With the advancement of succession, the large soil water-stable aggregates and mechanical aggregates increased, and the stability increased. From the pioneer community to the top community, the proportion of macroaggregates in the soil mechanical aggregates in the 20–40 cm soil layer increased by 36%, while that in the water-stable aggregates in the 10–20 cm soil layer increased by 19%. Compared with plantation, the stability of soil aggregates in natural forests with a similar age was stronger. Water-stable aggregates were negatively correlated with bulk density, density, and porosity, and positively correlated with organic-matter-related cement. The volume of the dominant tree, litter yield, tree species diversity, biomass of various tree species, and litter biomass in the undecomposed layer were the key indicators affecting the stability of aggregates. In terms of restoration measures, natural restoration is better than plantations with a single tree species. In addition, succession makes forest soil aggregates more stable. The change of dominant tree species leads to changes in soil aggregate stability, and the effect of organic-related cementing material was stronger than that of iron oxide. [ABSTRACT FROM AUTHOR]

Introduction: To document the successional processes of shrub-herb communities after large-scale human disturbance, and understand how changing environmental conditions affect species replacement in semi-humid hilly areas. Methods: Utilizing the established permanent plots in the hilly area of Taihang Mountain, we evaluated temporal patterns of vegetation and soil following grassto- shrub succession. Results and Discussion: Along secondary succession, Vitex negundo var. heterophylla gradually dominated in dry sunny slope and shared the dominance with Leptodermis oblonga in shaded slope. Herbaceous dominant species in shrub-herb communities switched from Themeda japonica, Bothriochloa ischaemum, Artemisia sacrorum, and Cleistogenes chinensis in 1986 census to B. ischaemum and A. sacrorum in 2008 census, but herb was no longer dominant in 2020 census. As succession progresses, species dominance increased while richness decreased generally, and herb cover and aboveground biomass decreased, whereas shrub height, cover, and aboveground biomass increased significantly. Soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), and total potassium (TK) in topsoil increased significantly while pH declined by 1.04 units over the past three decades. Plant communities transitioned from perennial herbs to shrub-herb and then shrub communities, and V. negundo var. heterophylla dominated in the succession of shrub-herb communities. Climate and soil properties, combined with plant attributes, together drive post-disturbance secondary succession. From a management perspective, the tight coupling between vegetation and soil under local climatic conditions should be considered to improve the fragile ecosystem in the hilly area of Taihang Mountain. [ABSTRACT FROM AUTHOR]

Question: Natural reforestation is an important component of climate mitigation and adaptation, but the ecological processes promoting or constraining it are poorly understood. In this study we employ a stand reconstruction approach (which uses ages of extant trees to estimate year of establishment for each individual tree) to test for general trait‐based effects on tree species arrival order in post‐agricultural forest successions. Location: Naturally reforesting post‐agricultural landscapes throughout New Zealand. Methods: Ages were obtained for 2434 individuals spanning 30 tree species across a nationwide network of 128 plots in 14 naturally reforesting post‐agricultural sites. These ages were used to calculate individual‐level arrival times (relative to the oldest individual in each plot). We estimated species‐level arrival times by fitting linear mixed‐effects (LME) regressions (with species identity as the fixed effect, and plots nested within sites as the random effects) to individual arrival time data. We used back‐casting (where arrival time data are used to document individual‐level presence in plots through time) to track annual changes in species abundance and community‐weighted mean (CWM) trait values. We used standardised major axis (SMA) regressions to examine the effect of traits related to resource use strategy, herbivory avoidance, seed dispersal and disturbance response on species‐level arrival times. We used LME regressions to test for changes in CWM trait values with stand age. Results: The earliest‐arriving species had traits associated with herbivory avoidance, were abiotically dispersed and had short predicted dispersal distances. There was no evidence that traits linked to resource use strategy or disturbance response affected species arrival times. Every significant species‐level relationship was recovered in community‐level LME analyses. Conclusions: Our findings suggest that mammalian herbivore control and enhancement of biotic (bird) seed dispersal may be key management interventions in realising the full climate mitigation and adaptation potential of natural reforestation in post‐agricultural landscapes. [ABSTRACT FROM AUTHOR]

Determining which species to utilize for the artificial restoration of subtropical secondary forests has become a focal point in forestry and ecology. To compare the effects of the subtropical secondary forest artificial restoration model on soil microbial nutrient acquisition and limitation, we examined secondary forests (CKs), evergreen coniferous forests (GCPs), evergreen coniferous mixed broad-leaved forests (GCBMs), evergreen mixed broad-leaved forests (GBMs), and natural deciduous broad-leaved mixed forests (DBMs) as research subjects. Among them, GCPs, GCBMs, and GBMs were dominated by the species of the early, middle, and climax stages of subtropical forest succession, respectively. The activities and stoichiometry of β-1,4-glucosidase (BG), β-1,4-N-acetylglucosaminidase (NAG), leucine aminopeptidase (LAP), and acid phosphatase (ACP) in the topsoil were analyzed. The results showed that the forest type significantly affects the activities of BG and LAP rather than NAG or ACP. The BG activity in DBMs was the lowest, while the LAP activity in CKs was significantly higher than that in plantations. Furthermore, the nutrient limitation of microbes was quantitatively analyzed by using the vector analysis of enzyme stoichiometry. The soil microbes in the study area were co-limited by C and P, and the nutrient limitation was in the order of C > P > N. Among the forests, the enzyme stoichiometric ratios in GCPs and DBMs were closest to 1:1:1. From CKs to GBMs, the microbial C limitation was increased, while the P limitation was decreased. The C limitation in DBMs was slightly lower than that in CKs. Overall, the P limitation in evergreen plantations was less than that in CKs. The soil bulk density, C/P, and N/P significantly influenced enzyme activities and stoichiometry. These results suggest that the artificial restoration of subtropical forests using evergreen species alleviated P limitation, while using deciduous broad-leaved species offered potential for alleviating microbial C limitation. Compared with evergreen broad-leaved species, employing pioneer and mid-successional or deciduous broad-leaved species can better achieve balanced microbial nutrient requirements.

Abstract The soil fungal community plays an important role in forest ecosystems and is crucially influenced by forest secondary succession. However, the driving factors of fungal community and function during temperate forest succession and their potential impact on succession processes remain poorly understood. In this study, we investigated the dynamics of the soil fungal community in three temperate forest secondary successional stages (shrublands, coniferous forests, and deciduous broad‐leaved forests) using high‐throughput DNA sequencing coupled with functional prediction via the FUNGuild database. We found that fungal community richness, α‐diversity, and evenness decreased significantly during the succession process. Soil available phosphorus and nitrate nitrogen decreased significantly after initial succession occurred, and redundancy analysis showed that both were significant predictors of soil fungal community structure. Among functional groups, fungal saprotrophs and pathotrophs represented by plant pathogens were significantly enriched in the early‐successional stage, while fungal symbiotrophs represented by ectomycorrhiza were significantly increased in the late‐successional stage. The abundance of both saprotroph and pathotroph fungal guilds was positively correlated with soil nitrate nitrogen and available phosphorus content. Ectomycorrhizal fungi were negatively correlated with nitrate nitrogen and available phosphorus content and positively correlated with ammonium nitrogen content. These results indicate that the dynamics of fungal community and function reflected the changes in nitrogen and phosphorus availability caused by the secondary succession in temperate forests. The fungal plant pathogen accumulated in the early‐successional stage and ectomycorrhizal fungi accumulated in the late‐successional stage may have a potential role in promoting forest succession. These findings contribute to a better understanding of the response of soil fungal communities to secondary forest succession and highlight the importance of fungal communities during the successional process.

In South China, large amounts of strongly eroded badlands that are difficult for natural recovery formed in red beds soft rock, posing serious environmental hazards. This process is thought to be related to a unique nutrient cycle and plant-soil feedback in alkaline soil. In this study, we investigated 44 plant communities and some soil samples to explore the reasons for this erosion from the perspective of secondary succession and its driving factors. The results showed that the natural secondary succession (NSS) in red beds soft rock is the sequence of primary forest to scrub grass, xerophytes, and badlands. Masson pine and Masson pine/Schima superba communities have formed under the efforts of artificial intervention restoration. The community ecological gradient (CEG) and deciduosity rate substantially increased along the NSS, whereas the biomass, and diversity index rapidly decreased. The plantation community showed the opposite trend with increasing recovery years. Limitations in terms of soil water content, pH value, and available nitrogen (AN) for the community markedly increased, and we confirmed these were the largest contributors to redundancy analysis at the community scale. Compared with acidic soil, alkaline soil with a rough texture and high pH could not maintain enough water for plants during dry seasons, which inhibited the absorption of AN by plants. Therefore, in primary forests, the CEG and deciduosity rates need to be increased so that the plant community can adapt to harsh environments. plantation forests achieved soil acidification through litter accumulation. In the scrub grass and xerophyte, continuous reduction in litter and the intensification of soil erosion destroyed the balance between red argillaceous rock bed erosion and species invasion, leading to community degradation. Therefore, much attention should be given to primary forest protection and limiting factors mitigation in degraded communities.

Understanding of secondary succession, long-used as a unifying theme in ecology, continues to be informed by early-20th century chronosequence studies of old fields in the southeastern United States. However, growing evidence suggests classical, site-based indicators of successional change alone are not robust enough to capture realized compositional variation in eastern North American forests a century later. We illustrate how long-term data can provide deeper insight into forest dynamics and help identify additional indicators for predicting successional change.Using 80 years of permanent plot data from 36 forest stands in the Piedmont of North Carolina (USA) as a case study within the model system examined by foundational authors, we examine long-term trends in tree species abundance in both old-field pine forests transitioning to hardwood dominance and long-standing hardwood stands representing a range of historical, topographic, and edaphic conditions. We use a suite of descriptive and multivariate analyses to examine these long-term data and to assess them within the context of site conditions and novel drivers of change (e.g., removal of chronic fire, hurricane damage, increase in herbivore populations, and introduction of non-native plants and pathogens).Results indicate that these southeastern forests have undergone various perturbations that have collectively resulted in forests that are developing differently than predicted by classical models. Of particular note is the low recruitment of putative climax species such as oaks (Quercus spp.) and hickories (Carya spp.) and their replacement by novel understory communities, dramatic loss of dominant species (e.g., Cornus florida) due to nonnative pathogens, overcrowding by invasive exotic species, shifts in stem size distributions due to deer herbivory, and overall accelerated shifts in successional trajectory due to hurricane damage.We propose that potential shifts in predator abundance, nonnative species dispersal risk, pest and pathogen potential, changes in disturbance regimes, and frequency and timing of high-intensity disturbance can interact in various ways leading to variable and sometimes stochastic successional outcomes, and so these variables should be considered repeatedly through time as indicators of successional change in addition to classically-utilized indicators such as underlying site and abundance conditions. Using such a broad (and even dynamic) suite of indicators of forest change can more comprehensively enable accurate, long-term successional floristics modeling and resulting ecological and silvicultural management of temperate forests.

Abstract The structure of urban secondary forests and their potential for meliponiculture in the eastern Amazon was studied in the municipality of Belterra, Pará. The sampling was carried out in 25 plots of 40 m2 in two areas (0.1 ha) of secondary forests (SF), in which three classes of DBH values were considered (C1:1 cm ≤ DBH ≤ 5 cm; C2: 5 cm < DBH ≤ 10 cm and C3: DBH ≥ 10 cm). a total of 230 individuals were registered in SF I, comprising 66 species and 27 botanical families and 185 individuals in SF II, comprising 43 species distributed in 24 botanical families. The highest richness and abundance were verified for C1, followed by C2 in both areas. In SF I, the basal area values (G=1.509) were higher than in SF II, while the total volume (V=20.21) was higher than SF I, the mean height for C3 was higher in SF II, and C1 and C2 were higher in SF I. The Shannon-Wiener diversity index was higher in SF I (H = 3.722) than in SF II (H=3.197). It was observed that 75% species have bee pollination systems (mellitophilous flora) and are thus considered sources of honey resources.

Background: Soil microbiomes are increasingly acknowledged to affect plant functioning. Research in molecular model species Arabidopsis thaliana has given detailed insights of such plant-microbiome interactions. However, the circumstances under which natural A. thaliana plants have been studied so far might represent only a subset of A. thaliana's full ecological context and potential biotic diversity of its root-associated microbiome. Results: We collected A. thaliana root-associated soils from a secondary succession gradient covering 40 years of land abandonment. All field sites were situated on the same parent soil material and in the same climatic region. By sequencing the bacterial and fungal communities and soil abiotic analysis we discovered differences in both the biotic and abiotic composition of the root-associated soil of A. thaliana and these differences are in accordance with the successional class of the field sites. As the studied sites all have been under (former) agricultural use, and a climatic cline is absent, we were able to reveal a more complete variety of ecological contexts A. thaliana can appear and sustain in. Conclusions: Our findings lead to the conclusion that although A. thaliana is considered a pioneer plant species and previously almost exclusively studied in early succession and disturbed sites, plants can successfully establish in soils which have experienced years of ecological development. Thereby, A. thaliana can be exposed to a much wider variation in soil ecological context than is currently presumed. This knowledge opens up new opportunities to enhance our understanding of causal plant-microbiome interactions as A. thaliana cannot only grow in contrasting soil biotic and abiotic conditions along a latitudinal gradient, but also when those conditions vary along a secondary succession gradient. Future research could give insights in important plant factors to grow in more ecologically complex later-secondary succession soils, which is an impending direction of our current agricultural systems. [ABSTRACT FROM AUTHOR]