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Background: Nutrient limitation is a universal phenomenon in terrestrial ecosystems. Root and mycorrhizal are critical to plant nutrient absorption in nutrient-limited ecosystems. However, how they are modified by N and P limitations with advancing vegetation successions in karst forests remains poorly understood. The present study compared the diversity indices, composition, and co-occurrence network of arbuscular mycorrhizal fungi (AMF) between grassland, shrubland, shrub-tree forest, and tree forest in subtropical karst forests, as well as soil nutrients and fine root functional traits (e.g., specific root length (SRL), specific root area (SRA), diameter, biomass, and N and P contents). Results: The fine roots diameter, biomass, and N and P contents increased with advancing succession, whereas SRL and SRA decreased. Network complexity and Richness and Chao1 indices of AMF increased from grassland to shrub-tree forest but decreased in tree forest. The fine roots N and P contents were positively related to their diameter and biomass, soil nutrients, and AMF composition but were negatively correlated with SRL and SRA. Moreover, these two parameters increased with the increase of soil nutrients. The variations in fine roots N and P contents were mainly explained by soil nutrients and fine root functional traits in grassland and by the interactions of soil nutrients, fine root functional traits, and AMF in the other three stages. Additionally, the interactive explanation with AMF increased from shrubland to shrub-tree forest but decreased in tree forest. Conclusions: Our results indicated that mycorrhizal strategy might be the main nutrient acquisition strategy under N and P co-limitation. In contrast, the root strategy is the main one when an individual is subject to limitations in N or P in karst ecosystems. Root and mycorrhizal nutrient acquisition strategies are generally mutualistic, mycorrhizal strategy enhances plant nutrient acquisition under N and P co-limitation. [ABSTRACT FROM AUTHOR]

The threat of declining seaweed beds has been a concern around the world. Seagrass and seaweed (brown algae) beds are essential habitats supporting fisheries. However, ~ 22% of these habitats have been lost in Japan due to increased coastal landfill sites and ports. This study aims to rehabilitate the depletion of these habitats by constructing an artificial reef in Wakasa Bay, Japan, and monitoring brown algae (Sargassum sp.) succession in 1 year and 3 years after the reef construction. In this study, we set up six sites on the artificial reef as a treatment area and three sites on the natural reef as a control area and then identified the seaweed species composition of the Sargassum community and their coverage on each reef using underwater visual observation by scuba divers. Significant differences between the artificial and natural reefs were identified. The seaweed species composition and coverage of the Sargassum community on the artificial reef differed from those on the natural reef in 3 years after the reef construction. On the artificial reef, the presence of S. horneri decreased and that of S. hemiphyllum/S. patens increased, whereas on the natural reef, S. patens dominated and S. macrocarpum increased. The seaweed species composition and coverage on the artificial reef had not caught up with those on the natural reef. The seaweed on the artificial reef is thus considered to be in the vegetation succession process, which has not yet reached the climax condition, while the natural reef has almost reached the climax phase. The Sargassum community monitoring on the artificial reef appears necessary to be continued in the next few years. [ABSTRACT FROM AUTHOR]

In urban industrial area, mining activity directly affects the dynamic of carbon, and consequently, the release of carbon dioxide (CO2) into the atmosphere. The main objective of this research is to study the impact of most important abiotic environmental factors on soil respiration in post-coalmine ecosystems. The moisture and temperature of the soil, along with CO2 outflow from the soil, were measured over three consecutive seasons, using 92 samples from coalmine heaps and 10 samples from deciduous forests in the same urban industrial region. Based on a survey of 396 species, a cluster analysis distinguished all deciduous and 22 forest plots grown on coalmine heaps from herbaceous plots from same coalmine heaps. The lowest soil respiration rate (0.62 mg CO2 per hour per square meter) was recorded in the herbaceous vegetation class on coalmine heaps, compared to (0.76 mg and 0.96 mg) from coalmine-heap forests and deciduous forests, respectively. Species richness and diversity positively affected soil respiration in heap herbaceous plots, though this effect was less pronounced in forests grown on coalmine heaps and in deciduous mixed forests. Unlike soil water content, soil temperature negatively correlated with soil respiration on coalmine heaps, diverging from the well-studied positive impact of soil temperature and respiration in deciduous mixed forests. Our spatial and temporal analyses emphasize that the water content of the substrate is the most significant abiotic element that affects the soil respiration on coalmine heaps positively during early vegetation succession. [ABSTRACT FROM AUTHOR]

Central European peatlands are critically endangered by climate change, eutrophication, disturbed water regime and inappropriate management. This leads to their degradation, which affects all components of these habitats including fungi, and significantly fungi participating in the carbon cycle such as saprotrophs, mycorrhizal symbionts and parasites. Nature conservation efforts focus mainly on macrofungi, especially ‘fungi important for nature conservation’ (FINC) which are rare or associated with endangered habitats. To find out whether standard environmental DNA (eDNA) sequencing methods can be used to monitor the effect of peatland degradation on FINC and fungal communities, we established pairs of plots in degraded and well-preserved parts of ten peatlands in the Třeboň Protected Landscape Area (Czech Republic). Peatland degradation was locally caused by a combination of different factors (water level and chemistry) followed by vegetation succession, whose effect on fungi was evaluated using multivariate analyses. A total of 28 FINC species were detected using macrofungal surveying, whereas 25 were found using eDNA of Sphagnum and peat (Illumina sequencing of ITS2). These two methods agreed on 13 predominantly abundant FINC species, most of which grew in both well-preserved and degraded plots. However, their sensitivity to the studied degradation could not be assessed due to the low abundance of most species. Fungal communities found on the basis of both methods (macrofungal survey, eDNA) were affected by water chemistry, whereas a significant effect of vegetation and locally expansive plants was demonstrated only in fungal communities found using macrofungal survey. Optimisation (e.g. specific primers) for local conditions leading to a better FINC capture must be carried out if eDNA is to be used in the practice of evaluating management effects on peatlands.

While the link between plant species diversity and biomass has been well‐studied, the impact of evolutionary diversity on community biomass across long timescales or ongoing change remains a subject of debate. We elucidated the association between evolutionary diversity and community aboveground biomass (AGB) using an ideal experimental system with over 150‐year history of natural vegetation regeneration. Higher phylogenetic diversity facilitated the sampling effect under the influence of environmental filtering, and caused an increase in AGB. Phylogenetic structure varied from aggregation to dispersion during the later period of vegetation recovery (70–150 years), which was correlated with increases in niche complementarity and increasing AGB. Woody plant evolutionary diversity was used as a key to predict the relationship between vegetation recovery and AGB, with a total explanatory power of ~84.7%. Mixed forests composed of evergreen conifers and deciduous broadleaf forests had higher carbon sequestration potential than that of pure forests, which is advantageous for increasing top‐stage AGB. This research expands our knowledge of the causes and effects of biodiversity and ecosystem function dynamics over time and space, which is important for accurately predicting future climate change effects. [ABSTRACT FROM AUTHOR]

Mediterranean landscapes were drastically affected by high levels of abandonment of agricultural and other land practices during the last century. These changes in land use can have significant effects on diversity patterns by altering disturbance and competition equilibria within plant communities at the landscape level. Particularly, such changes have been found to affect the patterns of phylogenetic diversity and structure by causing nonrandom losses of species through filtering effects and landscape homogenization. By investigating diversity patterns across a region submitted to high levels of land use changes, located in a (sub‐) mountainous area of northwestern Greece (northern Pindus), we aimed at understanding the patterns of phylogenetic diversity and structure in relation to land abandonment and the subsequent recovery of natural vegetation. We sampled 250 vegetation plots equally divided in grasslands and forests, distributed across the different classes of land use occurring in the general study area based on the period since the last change in land use. Standardized metrics of Faith's phylogenetic diversity, mean phylogenetic distance, and mean nearest taxon distance were used to investigate phylogenetic diversity patterns across communities and different land‐use regimes. A Principal Coordinates of Phylogenetic Structure analysis was employed to evaluate the variation in lineage composition among communities, and boosted regression trees were used to identify the relative influence of community differentiation (as captured by the classification of sampling plots in ecologically and floristically distinct vegetation communities), plant life strategies (competition, stress tolerance, and disturbance), and climatic, topographic, and soil variables on phylogenetic diversity metrics. Community differentiation was identified as the main driver of phylogenetic patterns. Additionally, phylogenetic diversity and structure were observed as having a statistically significantly negative correlation with disturbance, a statistically significantly positive correlation with stress tolerance, and a weaker positive correlation with competition. Phylogenetic clustering was observed for the early successional grassland communities submitted to stronger effects of disturbance, while phylogenetic randomness (or rarely overdispersion) was observed in forest communities submitted to stronger effects of competition. Finally, phylogenetic clustering of grassland communities was more evident shortly after land abandonment. [ABSTRACT FROM AUTHOR]

Soil metabolites are critical in regulating the dynamics of ecosystem structure and function, particularly in fragile karst ecosystems. Clarification of response of soil metabolism to vegetation succession in karst areas will contribute to the overall understanding and management of karst soils. Here, we investigated the metabolite characteristics of karst soils with different vegetation stages (grassland, brushwood, secondary forest and primary forest) based on untargeted metabolomics. We confirmed that the abundance and composition of soil metabolites altered with vegetation succession. Of the 403 metabolites we found, 157 had significantly varied expression levels across vegetation soils, including mainly lipids and lipid-like molecules, phenylpropanoids and polyketides, organic acids and derivatives. Certain soil metabolites, such as maltotetraose and bifurcose, were sensitive to vegetation succession, increasing significantly from grassland to brushwood and then decreasing dramatically in secondary and primary forests, making them possible indicators of karst vegetation succession. In addition, soil metabolic pathways, such as galactose metabolism and biosynthesis of unsaturated fatty acids, also changed with vegetation succession. This study characterized the soil metabolic profile in different vegetation stages during karst secondary succession, which would provide new insights for the management of karst soils. [ABSTRACT FROM AUTHOR]

The role of riparian vegetation in driving hydrogeomorphic development within rivers is increasingly recognised. Vegetation-mediated biotic-abiotic interactions are known to become dominant as landscapes develop, however to date the timescales and rates of these interactions remain poorly understood. Here, we outline how our ongoing research of river development in Glacier Bay National Park has allowed us to observe and quantify the role of instream wood in driving biotic-abiotic feedback mechanisms over a large spatiotemporal scale. Our research shows that the colonisation of riparian areas with small, relatively simple woody material (predominantly alder and willow boles) and its subsequent introduction into the river channel initiates the creation of hydrogeomorphic diversity which biotic communities are able to utilise. However, as riparian vegetation continues to develop through succession, the introduction of increasingly large and complex material (spruce and hemlock trees) exerts increasing control on instream conditions. This review highlights the role of instream wood in increasing river-terrestrial interactions, and incorporates instream wood into previous conceptual models related to fluvial biogeomorphological succession and ecosystem development within Glacier Bay. [ABSTRACT FROM AUTHOR]

Central European peatlands are critically endangered by climate change, eutrophication, disturbed water regime and inappropriate management. This leads to their degradation, which affects all components of these habitats including fungi, and significantly fungi participating in the carbon cycle such as saprotrophs, mycorrhizal symbionts and parasites. Nature conservation efforts focus mainly on macrofungi, especially ‘fungi important for nature conservation’ (FINC) which are rare or associated with endangered habitats. To find out whether standard environmental DNA (eDNA) sequencing methods can be used to monitor the effect of peatland degradation on FINC and fungal communities, we established pairs of plots in degraded and wellpreserved parts of ten peatlands in the Třeboň Protected Landscape Area (Czech Republic). Peatland degradation was locally caused by a combination of different factors (water level and chemistry) followed by vegetation succession, whose effect on fungi was evaluated using multivariate analyses. A total of 28 FINC species were detected using macrofungal surveying, whereas 25 were found using eDNA of Sphagnum and peat (Illumina sequencing of ITS2). These two methods agreed on 13 predominantly abundant FINC species, most of which grew in both well-preserved and degraded plots. However, their sensitivity to the studied degradation could not be assessed due to the low abundance of most species. Fungal communities found on the basis of both methods (macrofungal survey, eDNA) were affected by water chemistry, whereas a significant effect of vegetation and locally expansive plants was demonstrated only in fungal communities found using macrofungal survey. Optimisation (e.g. specific primers) for local conditions leading to a better FINC capture must be carried out if eDNA is to be used in the practice of evaluating management effects on peatlands. [ABSTRACT FROM AUTHOR]

Background: The Minqin Oasis, which is located in Wuwei City, Gansu Province, China, faces a very serious land desertification problem, with about 94.5% of its total area desertified. Accordingly, it is crucial to implement ecological restoration policies such as cropland abandonment in this region. In abandoned croplands, abiotic factors such as soil properties may become more important than biotic factors in driving vegetation succession. However, the connections between soil properties and vegetation succession remain unclear. To fill this knowledge gap, this study investigated these connections to explore major factors that affected vegetation succession, which is meaningful to designing management measures to restore these degraded ecosystems. Methods: This study investigated seven 1–29-year-old abandoned croplands using the "space for time" method in Minqin Oasis. Vegetation succession was classified into different stages using a canonical correlation analysis (CCA) and two-way indicator species analysis (Twinspan). The link between soil properties and vegetation succession was analyzed using CCA. The primary factors shaping community patterns of vegetation succession were chosen by the "Forward selection" in CCA. The responses of dominant species to soil properties were analyzed using generalized additive models (GAMs). Results: Dominant species turnover occurred obviously after cropland abandonment. Vegetation succession can be classified into three stages (i.e., early, intermediate, and late successional stages) with markedly different community composition and diversity. The main drivers of vegetation succession among soil properties were soil salinity and saturated soil water content and they had led to different responses of the dominant species in early and late successional stages. During the development of vegetation succession, community composition became simpler, and species diversity decreased significantly, which was a type of regressive succession. Therefore, measures should be adopted to manage these degraded, abandoned croplands. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the vertical distribution of soil nutrients in sand dunes of N. tangutorum nebkhas at different successional stages in the Ulanbuhe Desert, and to provide a scientific foundation for the stable growth of N. tangutorum shrubs in the region. [Methods]N. tangutorum nebkhas sand piles at different succession were selected stages as the research objects. Through preliminary vegetation investigation, based on the dead rate and coverage of the N. tangutorum shrub, it was divided into different succession stages, namely the development stage (dead rate 10％～30％, coverage 20％～40％), stable stage (dead rate＜10％, coverage 40％～60％), and decline stage (dead rate＞50％, coverage＜20％). Three relatively independent N. tangutorum nebkhas sand piles were selected for each succession stage. The vegetation characteristics and soil nutrients in the inter dune area and on windward and leeward slopes of sand piles were investigated and determined, respectively. [Results]As the succession of the N. tangutorum shrub progresses, the height, crown length, and width of the N. tangutorum first increased and then decreased. Among them, the crown length in the stable stage was significantly higher than that in other stages (p＜0. 05), increased by 45. 50％and 50. 01％compared to the developmental and declining stages, respectively (p＜0. 05). At the leeward slope, the soil nutrient content during the development stage shows a'descending ascending descending 'trend with the increase of soil depth, while the organic matter content during the stable and declining stages showed a decreasing trend, reaching the minimum value at 40-60 cm. At the windward slope, the content of soil organic matter and total nitrogen in 40-60 cm soil layer reached the maximum value in the decline stage with the development of the succession stage, but the content of total nitrogen in the development and decline stage reached the minimum value in 40-60 cm soil layer with the increase of the soil depth, which was 83. 33％and 80. 31％lower than that in 0-10 cm soil layer, respectively (p＜0. 05). The soil nutrients of the white thorn shrub sand pile at different slope positions reached their maximum values at 0-10 cm, but overall, the nutrient enrichment effect of the N. tangutorum nebkhas sand pile soil was not significant. [Conclusion]This research has shown that the soil nutrients in the N. tangutorum nebkhas sand pile are mainly concentrated on the surface of the sand pile. How to alleviate the activation of the N. tangutorum nebkhas sand pile and soil nutrient loss is an important guarantee for the stability of the N. tangutorum nebkhas sand pile in arid environments. [ABSTRACT FROM AUTHOR]

In urban industrial area, mining activity directly affects the dynamic of carbon, and consequently, the release of carbon dioxide (CO2) into the atmosphere. The main objective of this research is to study the impact of most important abiotic environmental factors on soil respiration in post-coalmine ecosystems. The moisture and temperature of the soil, along with CO2 outflow from the soil, were measured over three consecutive seasons, using 92 samples from coalmine heaps and 10 samples from deciduous forests in the same urban industrial region. Based on a survey of 396 species, a cluster analysis distinguished all deciduous and 22 forest plots grown on coalmine heaps from herbaceous plots from same coalmine heaps. The lowest soil respiration rate (0.62 mg CO2 per hour per square meter) was recorded in the herbaceous vegetation class on coalmine heaps, compared to (0.76 mg and 0.96 mg) from coalmine-heap forests and deciduous forests, respectively. Species richness and diversity positively affected soil respiration in heap herbaceous plots, though this effect was less pronounced in forests grown on coalmine heaps and in deciduous mixed forests. Unlike soil water content, soil temperature negatively correlated with soil respiration on coalmine heaps, diverging from the well-studied positive impact of soil temperature and respiration in deciduous mixed forests. Our spatial and temporal analyses emphasize that the water content of the substrate is the most significant abiotic element that affects the soil respiration on coalmine heaps positively during early vegetation succession.

China is currently the world’s largest carbon emitter and has pledged to achieve carbon neutrality by 2060, which requires significant reductions in emissions and the removal of carbon dioxide removal. Precise and efficient forestation has become a key strategy to increase carbon sequestration and mitigate the effects of climate change. In order to obtain a high-accuracy distribution area of potential forestation land, a variety of influencing factors on potential forestation land were selected in this study, including vegetation factors and environmental factors. Combining the two models “law of the minimum factors (LMF)” and “equal weight classification (EWC)” predicts the spatial distribution pattern of potential forestation land in China. And, we calculated the available forestation area in each province and predicted future forest coverage. The results showed that the potential forestation area using the LMF method reached approximately 5.65 × 105 km2, and the potential forestation area using the EMC method reached approximately 4.95 × 105 km2. Combining the two models, the final potential forestation area in China was approximately 6.29 × 105 km2, of which approximately 1.02 × 105 km2 was evaluated as a high-confidence area. If all potential forestation land obtained from the two models was successfully planted, China’s forest coverage rate would reach nearly 26 %. Two newly introduced vegetation factors, namely vegetation resilience and top vegetation succession, were considered in this study to make the prediction results of potential forestation distribution more accurate and reasonable. In addition, the results obtained in this study can provide certain assistance for the specific implementation of national forestation policies, and can provide a reference for promoting forestation actions and achieving the goal of carbon neutrality.

Phytoremediation is a sustainable way to clean contaminated urban soil, but selecting the right plants and designing communities is crucial. This study focuses on the vegetation in a disused steel plant in Chongqing, China, abandoned for nearly two decades. The goal is to reveal the plant community and succession patterns to inform the restoration of brownfield sites. This study combined the sample line and plot to investigate the vegetation and its growth environment in the Steel Plant. Information was recorded, including plant species, quantity, distribution, soil nutrients, humidity, and light. Cluster analysis categorized plant community types, and redundancy analysis examined the link between environmental conditions and plant types. The study found that: 1) There are 65 plant species (including 13 native trees) in the steel plant’s brownfield area, with Broussonetia papyrifera, Pteris vittata, and Debregeasia orientalis being the most abundant. The plants inside the plant were divided into seven groups based on species composition. 2) Soil moisture showed a significant positive correlation (Pearson index of 0.628) with plant survival, followed by a notable correlation with light intensity. 3) Environmental conditions partly influenced plant species composition and abundance variations. 4) 11 hyper-accumulating plant species were identified, focusing on three: the As hyper-accumulator Pteris vittata and the Cd hyper-accumulators Solanum nigrum and Debregeasia orientalis. The findings of this research will offer valuable insights for applying phytoremediation techniques in addressing contamination issues in brownfields within steel plants.

The disturbed forest system can be restored through successional processes, where changes in the diversity of plant species serves as key indicators of processes. Meanwhile plant water use efficiency and nitrogen dynamics are important factors influencing photosynthesis-water coupling and nutrient stress in plants, respectively, during forest recovery. Analyzing these factors is crucial for understanding forest recovery and promoting sustainable ecosystem development. In this study, traditional vegetation surveys and biodiversity indices, along with foliar stable carbon and nitrogen isotope analyses, as well as nitrogen content analyses, were conducted in a subtropical forest with various successional stages following human and natural disturbances in Sichuan province, China. These analyses were used to assess species diversity patterns, evaluate water use efficiency, and assess nitrogen dynamics in primary, secondary, and artificial forests. The results showed distinct stage-specific differences in succession among forest types. Primary forests exhibited the highest successional stage but were limited by water stress and high nitrogen competition, with the highest δ13C values (i.e., −29.0 ‰), lowest δ15N values (i.e., −3.6 ‰), and the lowest nitrogen contents (i.e., 3.6 %) on average. Artificial forests had the lowest species diversity due to species dominance and nitrogen competition, with the lowest δ13C values (i.e., −29.7 ‰), relatively low nitrogen contents (i.e., 4.0 %), and high δ15N values (i.e., −1.8 ‰). Secondary forests, with longer recovery periods, reached higher successional stage due to sufficient nitrogen and water, which is indicated by the highest δ15N values and nitrogen contents (i.e., −1.7 ‰ and 4.5 %), and the relatively low δ13C values (i.e., −29.4 ‰), leading to accelerated vegetation growth. This study highlights not only the importance of analyzing plant diversity, but also the material cycles, especially water use efficiency, and nitrogen dynamics, to understanding forest recovery. These findings can support effective conservation and sustainable development of subtropical forest ecosystems.

Background: Soil phosphorus (P) availability is crucial for the restoration of degraded ecosystems, but how soil organic P transforms during post-agricultural succession remains poorly understood in karst ecosystems. Methods: A typical recovery gradient including manual (orchard) and natural (grassland and secondary forest) vegetation restoration after agricultural abandonment was established in a karst region of southwest China. Sequential fractionation, solution 31P nuclear magnetic resonance (NMR) and enzyme assays were performed to investigate the chemical nature and biochemical transformation of organic P during post-agricultural succession in a karst region of southwest China. Results: We found significant redistributions of soil P fractions from inorganic P to organic P after agricultural abandonment. Specifically, orthophosphate decreased by 10.5% to 34.6%, while phosphomonoester and phosphodiester increased from 9.0% to 33.9% and 0.79% to 2.64%, respectively, during post-agricultural succession. The increased P limitation and organic P substrates induced higher phosphatase activities, with the highest acid phosphomonoesterase activity observed in secondary forest while the highest phosphodiesterase and alkaline phosphomonoesterase activities observed in grassland. Moreover, structural equation modelling demonstrated a clear increase in microbial production of alkaline phosphomonoesterase and the potential hydrolysis of phosphomonoesters under elevated P limitation. Conclusions: In summary, our findings suggested that agricultural abandonment caused redistributions of soil inorganic P to organic P, with alkaline phosphomonoesterase-mediated phosphomonoester turnover playing a crucial role in soil P availability during post-agricultural succession in karst ecosystem. [ABSTRACT FROM AUTHOR]

The sowing of species-poor and allochthonous grassland seed mixtures, the abandonment of traditional mowing and pasturing, and the intensification of agriculture, has led to a loss of biodiversity in the agricultural landscape of Central Europe. To restore biodiversity of species-poor grasslands in the Podyjí National Park, we used small-scale ploughing as an alternative disturbance management supporting plant colonization from the local species pool at twelve localities with different environmental conditions and management history. The main aim of our study was to evaluate changes in the flora and grassland vegetation following artificially induced disturbance in the form of different ploughing regimes. We compared plant species richness, plant species composition and vegetation changes between plots situated in annually ploughed, once ploughed and unploughed grasslands. Although we did not observe any significant changes in the total number of plant species among the treatments in the first years of succession, we recorded several rare and endangered plant species that appeared after ploughing. On the other hand, invasive species were not present in large numbers except at one site. Our results suggest that small-scale disturbances in the form of ploughing could be a suitable way to support and maintain local biodiversity mainly of dry or species-poor grasslands with a dominance of grasses whereas the ploughing of mesic and nutrient-rich grasslands leads to ruderal vegetation with Artemisia vulgaris, Elymus repens or even invasive Solidago gigantea. [ABSTRACT FROM AUTHOR]

Background The Minqin Oasis, which is located in Wuwei City, Gansu Province, China, faces a very serious land desertification problem, with about 94.5% of its total area desertified. Accordingly, it is crucial to implement ecological restoration policies such as cropland abandonment in this region. In abandoned croplands, abiotic factors such as soil properties may become more important than biotic factors in driving vegetation succession. However, the connections between soil properties and vegetation succession remain unclear. To fill this knowledge gap, this study investigated these connections to explore major factors that affected vegetation succession, which is meaningful to designing management measures to restore these degraded ecosystems. Methods This study investigated seven 1–29-year-old abandoned croplands using the “space for time” method in Minqin Oasis. Vegetation succession was classified into different stages using a canonical correlation analysis (CCA) and two-way indicator species analysis (Twinspan). The link between soil properties and vegetation succession was analyzed using CCA. The primary factors shaping community patterns of vegetation succession were chosen by the “Forward selection” in CCA. The responses of dominant species to soil properties were analyzed using generalized additive models (GAMs). Results Dominant species turnover occurred obviously after cropland abandonment. Vegetation succession can be classified into three stages (i.e., early, intermediate, and late successional stages) with markedly different community composition and diversity. The main drivers of vegetation succession among soil properties were soil salinity and saturated soil water content and they had led to different responses of the dominant species in early and late successional stages. During the development of vegetation succession, community composition became simpler, and species diversity decreased significantly, which was a type of regressive succession. Therefore, measures should be adopted to manage these degraded, abandoned croplands.

Abstract Soil organic matter is closely linked to the quality of Agroecosystems and directly influences the agricultural production and the environmental conditions. Understanding of soil organic matter dynamics in agroforestry systems requires studies with a temporal focus, since the changes in its chemical composition tend to follow a gradual behavior. The aim of this study was to investigate the dynamics of changes in stocks and chemical composition of soil organic matter under agroforestry, using systems in different stages of vegetation succession. The soil sampling was carried out from trenches, and litter fractions were also sampled. The samples were collected from different layers of the soil profile under the following conditions: Control; agroforestry with 1 year; agroforestry with 3 years; agroforestry with 7 years and Forest in natural regeneration. The following attributes/parameters were determined/calculated: i) C and N contents and stocks and C/N ratio; ii) C and N proportions in soil granulometric fractions and iii) kinetics of organic matter accumulation in soil with the time of systems evolution. The results showed: i) The C/N ratio tended to increase in depth but did not show a clear variation between the systems evaluated; ii) the adoption of successive agroforestry practices has the potential to increase the C and N stocks in soil; iii) the soil organic matter accumulation occurs gradually during the systems evolution and is mainly related to the particulate fraction (> 0.053 mm).

Background: High-severity fires are serious anthropogenic threats to forests, as they can cause forest degradation on unrecoverable scales. Therefore, understanding the patterns and drivers of post-fire regeneration is essential to designing restoration proposals. Hypotheses: After a high-severity fire, we expected greater species richness and abundance of individuals in flat sites than in hillside sites since seeds, nutrients, and organic matter accumulate in flat landforms. Compared to some Pinus species, Quercus species are more drought-tolerant after a forest fire and, therefore, they are expected to dominate post-fire chronosequences. Study site: The study was conducted in the “La Primavera” Flora and Fauna Protection Area. Methods: We sampled vegetation and microenvironmental variables from 2021 to 2022 at 18 sites located on flat and hillside areas, at 3, 9, and ≥ 20 years since the last high-severity forest fires (TSF). Results: The richness of woody and herbaceous species was higher at 3 TSF and 9 TSF. The topographic condition did not significantly drive the richness and abundance of woody species, but richness and abundance of herbaceous species were significantly greater in flat sites. The oak tree Quercus resinosa Liebm. was the dominant species throughout the chronosequence. Conclusions: Quercus resinosa represents a foundational species for recovering forest structure and composition. Flat sites may act as regeneration nuclei, but hillside sites require greater restoration efforts.

Landslides have received significant attention as an important natural disturbance that maintains biodiversity, but most previous studies have focused on the early stages of succession during years or decades in sites or small watersheds. The present study aimed to determine what regional drivers influence long-term ecological succession in large, ancient landslide scarps across a mountainous region in Japan. A landscape-level analysis of 993 landslide scarps using GIS revealed that climatic factors, especially snowfall, are important regional drivers of vegetation development on landslide head scarps in the region. While vegetation has developed on ancient landslide scarps, not all of them have returned to their pre-landslide vegetation state even though hundreds or thousands of years may have passed. The relationship between the number of vegetation types and maximum snow depth shows that where the maximum snow depth is less than 100 cm, more than 50% of the landslide scarps are covered by one type of vegetation, and the percentage of scarps covered by one type of vegetation decreases with increasing snow cover. The deeper the snow, the more vegetation types tend to develop on the landslide scarps. Since forest vegetation cannot develop due to heavy snow, meadows, grasslands, and shrublands are found on the scarps. It is concluded that the combined effects of both landslide-caused disturbances and climatic factors are creating regional diversity in vegetation types. [ABSTRACT FROM AUTHOR]

Wetland vegetation plays a crucial role in wetland conservation policy formulation and global climate change research. This study analyzed remotely sensed images of West Dongting Lake (DTL) Wetland from 1994 to 2020. This wetland is one of the most important wetlands in the world. At the pixel scale, we applied the histogram comparison approach, the range variability analysis (RVA) method, and the structural equation model (SEM) to quantify spatial changes in the hydrological conditions of wetland lakes and the ecological effects of environmental factors (precipitation, temperature, nutrients, water coverage) on vegetation. We propose a climate (C) — hydrological status (S) — vegetation response (R) (CSR) framework to elucidate the propagation relationships between climate, hydrology, and wetland vegetation conditions. The study found that the hydrological degradation promotes the succession of vegetation into the lake, and the distribution is concentrated in the northern Yangtze River inflow area. And the extent of hydrological changes in the West DTL region reached 34.5% during the flood period. In addition, the post-dam period showed a high degree of hydro-ecological failure, accounting for 65% of the total. Within the wetland area, there was a significant negative correlation between water coverage nutrient levels and bare vegetation within the lake area. Nutrient levels were also significantly negatively correlated with wetland vegetation conditions. Rainfall and temperature influence wetland vegetation by affecting the condition of the water body. This research provides valuable insights into managing wetland water resources and ecological restoration under the influence of climate change and human activities and provides a basis for decision-making. [ABSTRACT FROM AUTHOR]

Soil microbes are the primary drivers of the material cycling of the forest ecosystem, and understanding how microbial structure and composition change across succession assists in clarifying the mechanisms behind succession dynamics. However, the response of soil microbial communities and assembly processes to succession is poorly understood in subtropical forests. Thus, through the "space instead of time" and high throughput sequencing method, the dynamics of the soil bacterial and fungal communities and assembly process along the succession were studied, where five succession stages, including Abandoned lands (AL), Deciduous broad-leaved forests (DB), Coniferous forests (CF), Coniferous broad-leaved mixed forests (CB), and Evergreen broad-leaved forests (EB), were selected in a subtropical forest on the western slope of Wuyi Mountain, southern China. The results demonstrated that succession significantly decreased soil bacterial α-diversity but had little effect on fungal α-diversity. The composition of soil bacterial and fungal communities shifted along with the succession stages. LEfSe analysis showed the transition from initial succession microbial communities dominated by Firmicutes, Bacteroidota, Ascomycota, and Chytridiomycota to terminal succession communities dominated by Actinobacteriota and Basidiomycota. Distance-based redundancy analysis (db-RDA) revealed that soil total organic carbon (TOC) was the main factor explaining variability in the structure of soil bacterial communities, and multiple soil environmental factors such as the TOC, soil total nitrogen (TN), C:N ratio, and pH co-regulated the structure of fungi. The null models illustrated that deterministic processes were dominant in the soil bacterial communities, while the stochastic processes contributed significantly to the soil fungal communities during succession. Collectively, our results suggest that different patterns are displayed by the soil bacterial and fungal communities during the succession. These findings enhance our comprehension of the processes that drive the formation and maintenance of soil microbial diversity throughout forest succession. [ABSTRACT FROM AUTHOR]

We investigated the changes of soil nutrients and plant communities in the artificial sand fixation forests of Caragana korshinskii with different ages. The results showed that soil organic carbon and soil total nitrogen contents increased with the stand ages, and were significantly higher in 40 and 50 year-old than other ages. Soil organic carbon and total nitrogen contents recovered much faster in the surface layer (0-10 cm) than in others. Soil nutrient stoichiometric ratios (C:P, N:P) in the 0-10 cm soil layer differed significantly among different stand ages. With the increases of stand age, C and N contents in C. korshinskii leaves increased significantly, and reached the maximum at 50 year-old. Leaf P content increased first and then decreased, being maximum at 18 year-old. Leaf C: N first increased and then decreased, being maximum at 12 year-old. The contents of photosynthetic pigments and leaf C:P and N: P decreased first and then increased, being minimum at 18 year-old. C. korshinskii was mainly influenced by N availability before 40 year-old, but mainly limited by P after. The species number, density, and vegetation cover of annual and perennial herbaceous plants increased with stand ages, and the community shifted from a simple shrub plant community to a complex shrub-herb community. The biomass of C. korshinskii and herbaceous plants increased significantly with stand age, and had a significant positive correlation with the contents of soil organic carbon, total nitrogen and N:P. [ABSTRACT FROM AUTHOR]

The contradiction between humans and land is prominent in the karst area of Southwest China. Human destruction of vegetation eventually leads to serious water loss and soil erosion, resulting in a large number of rocky desertification. In order to control the expansion of rocky desertification, the Chinese government has carried out a series of projects, such as returning farmland to forest, natural forest protection and Yangtze River shelterbelt projects, which have caused corresponding changes in land use and vegetation cover. As one of the most important types of rocky desertification control in China, karst graben basins are usually characterized by drastic changes in basin-mountain topography, great climate contrast, severe soil flow/loss, poor vegetation site conditions, and the slow recovery of community ecosystem. Therefore, the study on the comprehensive control of rocky desertification at the karst graben basin became urgent. The ecological stoichiometry is a state-of-the-art science that analyzes the regional circulation patterns of biogeochemical elements from the perspective of element metrology, which provides a new insight to solve the problem of nutrient supply/demand and circulation in ecosystems. It has important application value in the study of soil nutrient circulation and balance mechanism, and is one of the hot spots in current ecological research. However, domestic studies on ecological stoichiometry mainly select desert steppe, Loess Plateau and Minjiang River estuary as research areas in recent years. There is a paucity of systematic studies on soil metrology characteristics in different stages of vegetation succession at karst graben basins, and the response of soil nutrients and ecological stoichiometry to different types of vegetation restoration is still unclear. In order to elucidate the content and stoichiometric ratios of C, N and P elements in the soils in different stages of vegetation succession at karst graben basins, Santang, located in Xiaojiang karst basin, Luxi county, Yunnan Province, was selected as a study area. This area is dominated by a subtropical monsoon climate, with the average annual temperature of 15.2 °C, the average annual sunshine of 2,122 h, and the average annual precipitation of 1,000 mm. The main tree species in the study area include Platycladus orientalis (L.) Franco, sticky alder, Yunnan pine, and so on. In January 2018, by the "space for time" approach, the soils from 5 different stages of vegetation succession (corn land, grassland, shrub land, planted forest and primary forest) were collected from different soil depths (0--10 cm and 10--20 cm) according to the sampling method of profile excavation. The soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) contents were determined by potassium dichromate oxidation with an external heating method, Kjeldahl method, and molybdenum antimony anti-colorimetric method. Excel 2019 software was used for data statistics. One-Way ANOVA, Duncan's new multiple range test method (LSD), Pearson correlation and Two-way ANOVA in SPSS 25.0 software were used to study the variance and correlations of soil ecological stoichiometric characteristics. The study results are expected to further reveal nutrient restriction and nutrient change patterns in the vegetation succession process, meanwhile, providing the scientific basis for vegetation restoration management and rational use of land resources in karst graben basins. There were significant differences in soil nutrient contents in different succession stages, mainly manifested in the 0--10 cm soil layer. SOC and TN contents showed an overall increasing trend with the increase of succession years, while TP content fluctuated and showed no obvious change pattern. Soil C and N contents differed significantly among soil layers. Specifically, SOC and TN contents in 0--10 cm soil layer were higher than those in 10--20 cm soil layer at each succession stage. Compared with C and N contents, soil P content did not differ significantly among soil layers at each succession stage, except for the content in the primary forest. In 0--10 cm soil layer, C/N, C/P and N/P showed significantly positive correlations with SOC content; C/P and N/P indicated significantly positive correlations with TN content; soil TP content was not significantly correlated with C/N, C/P and N/P. There was no significant correlation between soil physicochemical properties and soil stoichiometric ratio in the 10--20 cm soil layer. In the present study, the N/P ratios of 0--10 cm soil in different succession stages were between 2.71 and 5.93, and those of 10--20 cm soil were between 3.11 and 4.92. Essentially, all of the N/P ratios of soil at different depths were lower than 10, indicating that vegetation growth in the study area was more likely to be limited by N. However, given the fact that P content in karst soil is relatively low, vegetation growth should be first limited by P rather than N. Moreover, vegetation types and soil depths significantly affected SOC, TN and TP contents and their stoichiometric ratios in the study area. In summary, soil nutrient and stoichiometric ratios at karst graben basins change significantly with vegetation restoration chronosequence, and soil physicochemical properties have an important impact on soil stoichiometric ratios. These results are of great significance for further research on soil nutrient balance and limiting factors in karst graben basins. [ABSTRACT FROM AUTHOR]

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Seismic lines are the dominant anthropogenic disturbance in the boreal forest of the Canadian province of Alberta, fragmenting over 1900 km2 of peatland areas and accounting for more than 80% of all anthropogenic disturbance in this region. The goal of this study is to determine whether the wildland fires that burn across seismic lines in peatlands result in the regeneration of woody vegetation within the ecotonal areas adjacent to seismic lines. We use a combination of seismic line and vegetation structural characteristics derived from multi-spectral airborne lidar across a post-fire peatland chronosequence. We found an increasing encroachment of shrubs and trees into seismic lines after many years since a fire, especially in fens, relative to unburned peatlands. Fens typically had shorter woody vegetation regeneration (average = 3.3 m ± 0.9 m, standard deviation) adjacent to seismic lines compared to bogs (average = 3.8 m ± 1.0 m, standard deviation), despite enhanced shrubification closer to seismic lines. The incoming solar radiation and seismic line age since the establishment of seismic line(s) were the factors most strongly correlated with enhanced shrubification, suggesting that the increased light and time since a disturbance are driving these vegetation changes. Shrub encroachment closer to seismic lines tends to occur within fens, indicating that these may be more sensitive to drying conditions and vegetation regeneration after several years post-fire/post-seismic line disturbance. [ABSTRACT FROM AUTHOR]

Improving drought tolerance of psammophytes is a challenge for vegetation restoration in arid lands. Despite extensive reports on the effect of arbuscular mycorrhizal fungi (AMF) on plant resistance, its enhancements of drought resistance for psammophytes from different successions stages have been rarely explored. Here, seedlings of the Artemisia wudanica (early succession), Hedysarum fruticosum (middle succession), and the Caragana korshinskii (late succession) were selected to investigate the effect of AMF on the growth of psammophytes in different successional stages. We found that the mycorrhizal colonization of late‐successional psammophytes with the AMF was greater than that of the early and mid‐successional psammophytes. The effect of AMF on drought resistance was stronger in late‐successional psammophytes and the promotion effect increased with the intensity of drought. The AMF reduced the difference between aboveground and belowground plant growth and promoted more belowground growth of psammophytes in the late‐successional stage. We concluded that AMF can enhance the drought resistance of psammophytes and has a more significant effect on the growth of plants from the late‐successional stage. This study highlighted the importance of AMF for psammophytes, providing a new approach to improving the growth of psammophytes under drought circumstances. [ABSTRACT FROM AUTHOR]

The thinning vegetation and soil erosion problems left behind by extractive mining have caused serious environmental pollution, and vegetation restoration is one of the effective strategies to counter them. To study the effects of vegetation restoration on plant community species diversity, soil carbon, nitrogen and phosphorus, and the response of their plant community succession, four communities of different ages (1, 7, 10, 40) and one natural forest (>50 years) in the Kunyang phosphate mine were selected, and the analysis was carried out using the methods and protocols for plant community inventory. The species composition was recorded, and soil was collected from 0–60 cm in each community to determine the response of soil nutrients and plant diversity to the restoration process. The results show that the species richness of the community increases with the restoration year, the species composition at 40 years of restoration is similar to that of the natural forest, and the Shannon–Wiener diversity index in the tree layer at 40 years of restoration is greater than in the natural forest. Soil pH showed a decreasing trend with restoration year, and TP and AP increased with increasing time series. And the linear stepwise regression analysis showed that soil pH, soil organic carbon (SOC), total phosphorous (TP), available phosphorous (AP), and restoration year were the main factors of plant diversity. Compared to restoration of 10 years, TP and AP at the restoration of 40 years increased to 11.9–20.0 g∙kg−1 and 33.4–75.5 mg∙kg−1. The SOC of the community reached a maximum at 40 years of restoration, 1.5, 2.8, and 2.4 times higher at 0–20 cm, 20–40, and 40–60 cm, respectively, than at 1 year. The organic carbon fraction increased with the restoration year in an 'N' pattern, and mineral-associated organic carbon (MOC) and unstable organic carbon fraction decreased at 10 years and 40 years of restoration. The SOC of natural forests decreased, but stable organic carbon increased. The soil pH, SOC, and organic carbon fraction of the communities decreased with increasing soil depth, while TP and AP increased with increasing soil depth at the later period of restoration. In general, with extended restoration years, 40 years plant of restoration in phosphate mines can be expected to allow for plant community succession to climax community, and the key influence on plant diversity are the phosphorus and stable carbon fractions. These results are expected to facilitate the future basis for vegetation succession and restore systems during mining area restoration. [ABSTRACT FROM AUTHOR]

Large-scale afforestation is considered a natural way to address climate challenges (e.g., the greenhouse effect). However, there is a paucity of evidence linking plant diversity to soil carbon sequestration pathways during long-term natural restoration of temperate vegetation. In particular, the carbon sequestration mechanisms and functions of woody plants require further study. Therefore, we conducted a comparative study of plant diversity and soil carbon sequestration characteristics during 150 years of natural vegetation restoration in the temperate zone to provide a comprehensive assessment of the effects of long-term natural vegetation restoration processes on soil organic carbon stocks. The results suggested positive effects of woody plant diversity on carbon sequestration. In addition, fine root biomass and deadfall accumulation were significantly positively correlated with soil organic carbon stocks, and carbon was stored in large grain size aggregates (1-5 mm). Meanwhile, the diversity of Fabaceae and Rosaceae was observed to be important for soil organic carbon accumulation, and the carbon sequestration function of shrubs should not be neglected during vegetation restoration. Finally, we identified three plants that showed high potential for carbon sequestration: Lespedeza bicolor, Sophora davidii, and Cotoneaster multiflorus, which should be considered for inclusion in the construction of local artificial vegetation. Among them, L. bicolor is probably the best choice. [ABSTRACT FROM AUTHOR]

The Miyanaka Intake Dam fishway underwent improvements in 2012, and we established a new rock-ramp fishway called the Seseragi Fishway, cognizant of its utility as a passage and a habitat for bottom-dwelling and small fish with weak swimming ability. However, the fishway is occasionally submerged by floods, causing sediment accumulation that leads to changes in the vegetation composition. In addition, the arrival and inflow of seeds from upstream and the surrounding areas result in vegetation changes. In this study, the inside and outside of the rock-ramp fishway were divided into eight areas, and the vegetation succession after 2012 was determined. A correlation was observed between the results of fish catch surveys during the same period and the vegetation. Based on these results, we reported on the process of steadily operating the rock-ramp fishway while devising and improving specific management methods. Changes in vegetation, such as an increase in upright vegetation and a decrease in flow-obstructing vegetation, contributed to an increase in the population of bottom-dwellers, weak swimmers, and juvenile fish. The existence and management of appropriate vegetation are important for maintaining fishways inhabited by a variety of fish species. [ABSTRACT FROM AUTHOR]

Peat is an important archive allowing the reconstruction of past mire environments and surrounding vegetation. The Pihoviny site, one of the oldest peat deposits in the Bohemian-Moravian Highlands, was analysed for macrofossils and pollen and compared with other profiles in the region. The local mire development started in the Late Glacial as sedge-moss quaking fen with tundra elements characterised by high mineral richness and groundwater level. During the Early Holocene, it developed through the rich fen with hummocks, willow and reed stage to the waterlogged spruce forest, which persisted for thousands of years until the post-mediaeval deforestation. The recent mire vegetation developed 300 years ago due to human-induced deforestation. Further, we revealed high regional synchronicity among pollen profiles in the Early-Holocene (10,000–9000 cal BP), when open-canopy pine-birch forests transformed into closed-canopy deciduous forests due to climate improvement. Contrary, the Late-Holocene transformation to beech-fir forests was not synchronous, suggesting another driver than climate, likely human activities. Although pollen of both late-successional trees occurred since the Early Holocene, their expansion began much later, 5500–3500 (beech) and 3500–2500 cal BP (fir). Numerous spruce macrofossils suggest its pollen's local origin in the waterlogged spruce forest. Our results support the need for active management to sustain open mire vegetation and prevent spontaneous forest regrowth, recently boosted by climate warming. Palaeoecological analyses reconstructed a mosaic of waterlogged spruce and terrestrial beech-fir forests in the landscape, which should be restored to increase forest resistance against bark-beetle breakdowns and other disturbances in future. [ABSTRACT FROM AUTHOR]

Vegetation and fire archives of the late Holocene are essential for understanding the importance of natural and anthropogenic forcings on past and future vegetation successions as well as climate changes. Here we present a 1640-year record of vegetation and fire history of the Lake Haixihai catchment in northwestern Yunnan, southwest China. Pollen and charcoal analyses as well as XRF (X-ray fluorescence) analysis of lacustrine sediments from Lake Haixihai were employed to reveal its regional vegetation, forest fire, and soil erosion intensity changes over the last 1640 years. The results show their significant changes attributed to both climatic conditions and human activities: The lake catchment witnessed the densest forests (including pine and hemlock forests, and evergreen broadleaved forests) and the weakest soil erosion of the last 1640 years as well as relatively frequent forest fires at 380–880 AD, when vegetation succession, forest fire, and soil erosion were mainly driven by natural forcings, i.e., climatic conditions. A significant and abrupt drop in forest density, minor changes in abundance of forest components, and gradually strengthening soil erosion occurred at the transition from 880 to 1040 AD, when anthropogenic forcings such as the development of agriculture and systematic deforestation gradually became dominant ones driving vegetation succession and soil erosion. After this transition, forest density and soil erosion intensity never returned to the level before 880 AD, implying that the modern landscape in the lake catchment was already established approximately at as early as ca. 1040 AD. No significant changes in forest component and density as well as forest fire and soil erosion occurred until 1940 AD. The most frequent forest fires, the strongest soil erosion, and low forest density after 1940 AD might be attributed partially to climatic conditions and partially to extensive deforestation around 1960 AD. [ABSTRACT FROM AUTHOR]

Marble has been extracted from the Carrara quarries (Apuan Alps, Italy) for over two millennia. This cultural landscape is characterised by singular landforms called ravaneti, causing environmental problems due to debris flow, thus imperilling human settlements and natural heritage. Geomorphological and vegetation analyses have highlighted that in a decade, vegetation cover greatly increased, indicating potential for passive restoration of dump deposits. The assessment of plant assemblages indicates a decrease in plant richness and endemics, and an increase in wood and alien species. The conservation of historical ravaneti landscape requires weighted restoration actions to reduce geomorphological hazards and preserve native biodiversity. [ABSTRACT FROM AUTHOR]

Land abandonment is one of the main drivers of land use/land cover (LULC) change across Europe, which has already led to a significant loss of open habitats, threatening species hosted in them. We investigated LULC changes for a period of 70 years in a mountainous area of central Greece (Mt Agrafa) by mapping its land cover for the years 1945, 1996 and 2015, calculating transition matrices of land cover classes and performing intensity analysis at different levels. Subareas of the study area, with different population trends, were compared in regard to their LULC change trends. Possible drivers of LULC changes were explored by means of Random Forest modeling, and landscape metrics were calculated to assess their trends. Our results showed great changes in LULC class cover, significant shrinkage of open habitats, accelerated rates of change in the recent period and no differences in LULC change patterns in relation to different population trends. Variables expressing favorability of ecological conditions for forest establishment or probability of farmland abandonment were found as more important drivers of the spatiotemporal distribution of LULC classes, while landscape metrics revealed certain trends. Our main conclusion is that land abandonment and the subsequent vegetation succession are going through a semifinal stage, before their completeness and the almost absolute dominance of the forest, and repopulation of the countryside cannot unconditionally ensure any halting effect on the land abandonment process. [ABSTRACT FROM AUTHOR]

Vegetation plays an important role in the flow of material energy and nutrient cycle in the ecosystem. Karst vegetation is one of the main factors to maintain the stability of karst ecosystem function. At the same time, as a medium connecting soil, atmosphere and rock, plants not only present the characteristics of water balance in hydrologic and ecological processes, but also are an important link in regional vegetation restoration which is the basis of ecological construction and rocky desertification control in karst areas. In order to comprehensively understand the research progress, development trend and hot issues of karst vegetation restoration at home and abroad, literature related to this topic from 1985 to 2021 was retrieved from the Web of Science Core Collection Database (WoS) and China National Knowledge Infrastructure (CNKI) in this study. Based on high-frequency keyword analysis, keyword co-occurrence and cluster analysis, time evolution analysis of research subject, etc., the focuses and trends of karst vegetation restoration were analyzed. The results show that 319 and 351 related articles were collected respectively in WoS and CNKI databases from 1985 to 2021, and the number of articles published in 37 years experienced an increase with fluctuation. The publishing of these articles could be divided into three stages, the first stage (before 2005), an initiation stage of the research, in which the number of articles published was small; the second stage (2005-2015), a stage with a significant increase of literature due to great attention from domestic and foreign scholars to the ecological reconstruction of karst areas; the third stage (2015-2021), a rapid development stage, in which the number of international publications saw a continuous increase, while the domestic number showed a rise with fluctuation, and the growth rate of domestic research is significantly higher than that of international research. Rocky desertification, vegetation succession, soil nutrients and species diversity are high-frequency keywords in the literature, reflecting the common concerns of domestic and foreign research. Among them, vegetation succession law, soil nutrients and species diversity are the core issues in studies on karst rocky desertification areas. International studies on karst vegetation restoration pay more attention to ecosystem services and climate change, while domestic studies mainly focus on vegetation restoration in karst rocky desertification areas in the early stage, and pay more attention to the effects of vegetation restoration on soil properties and plant community composition in the later stage. In recent years, the diverse configuration of karst vegetation restoration technology and mode, for example, Huajiang Mode, Pingshang Mode, Huanjiang Mode, Pingguo Mode, etc. put forward through test, research and development, has become one of the research focuses. In addition, environmental benefits of vegetation restoration (moisture, nutrients, soil and water loss, etc.), soil seed banks, microbe and plant functional groups, vegetation restoration and forestry industry (understory economy and ecological industry), karst plant restoration and karst carbon sink, etc. have gradually become new hot issues in the research field of karst vegetation restoration. In the research of "vegetation restoration", the issues about industrial development such as fruit forest for ecological economy, governance and management modes for ecological economy, etc. have also been taken into account. In recent years, the restoration of karst vegetation (the control of rocky desertification) in China is closely related to the projects of poverty alleviation and elimination, for example, Huajiang Mode --the establishment of comprehensive management of industry for ecological environment in medium-intensity rocky desertification areas in karst plateau canyon, Pingshang Mode--the facilitation of vegetation restoration by planting honeysuckle in the rocky desertification control of Zhenfeng county, Huanjiang Mode characterized with ecological migration, and the Pingguo Mode characterized with the dragon fruit planting in Pingguo county. Due to the slow soil formation rate, thin soil layer and easy soil erosion, the karst area falls into a typical vulnerable ecosystem in the world, and the vegetation restoration in this area is very difficult. Therefore, the vegetation restoration mode is selected for the purpose of improving soil structure and coordinating the balance among soil water, fertilizer, air and heat. In order to promote the development of karst vegetation restoration research, it is suggested to strengthen domestic and international cooperation, and to set up some observation points in the field to observe and compare the dynamics of karst vegetation restoration in different regions for a long time. By comparing the spatio-temporal changes of large scale at home and abroad, the function and significance of vegetation restoration process on ecological restoration in karst areas can be analyzed through monitoring data. Through the restoration technology, model and evaluation method of karst vegetation system, the construction of karst ecosystem and the multi-scale pattern of vegetation diversity from the perspective of life community of mountain, forest, field, lake and grass and the perspective of rural industry can be further revealed. By comparing the research at home and abroad, some new ideas will be provided for ecological restoration in karst areas. [ABSTRACT FROM AUTHOR]

Plant–soil water relations are important for understanding the development of plant communities, especially in arid and semiarid areas. However, the interactions between vegetation characteristics and soil water dynamics in the restored grasslands along succession chronosequence were limitedly understood. In this study, we measured the functional traits of dominant species, plant community characteristics and soil water dynamics in grasslands restored for 5, 15, and 30 years (RG5, RG15 and RG30, respectively), and investigated the linkage between plant traits and soil water at the community/plot scale. The results showed that soil water content was high at RG5, while soil water storage increment at RG5 was low. With soil water content highest at RG5 (16.25%), decreased at RG15 (14.81%), and then recovered in some degree at RG30 (15.2%), dominant plant species changed from pioneer species Artemisia capillaries to perennial legume Lespedesa davurica with high specific leaf area, and finally to perennial forb Stipa bungeana with low specific leaf area and low shoot/root ratio. Plant community characteristics including aboveground biomass, vegetation coverage, species diversity all increased with restoration and reached the highest value at RG15 or RG30. Aboveground biomass of perennial grass, as well as species richness showed a significantly positive relationship with soil water recharge and soil water storage increment at deeper layers (10–120 cm and 40–120 cm). Species diversity had positive correlations with soil water content in 0–10 cm layer, a negative correlation with soil water storage increment in 0–10 cm layer and no correlation in 10–20 cm layer. Our findings suggested that changes in soil water content might enhance perennial grass species in semiarid grasslands, and time lag also existed in the plant–soil water interactions. [ABSTRACT FROM AUTHOR]

Natural solutions by which humans can overcome challenges have been severely hampered by biodiversity losses. It is essential to understand the key natural variables that influence changes in community diversity to maintain ecosystem function. The Ziwuling area has a natural recovery succession history of 150 years. Therefore, a survey was conducted to compare species composition characteristics across different vegetation recovery stages while also providing a phylogenetic and taxonomic response to the correlation between beta diversity and soil stoichiometry. The results showed that beta diversity and endemic plants had a similar single-peak temporal pattern. Soil organic carbon (SOC) accumulation was significantly positively correlated with total nitrogen (TN) and was also negatively correlated with total phosphorus (TP). Overall, soil TN, time since vegetation restoration (TVR in years), and W-SS (endemic woody plants at each stage) were able to explain 94.3% of the total variation in beta diversity. Temperate species such as Carex lanceolata, Lespedeza bicolor, and Sophora davidii are the basis for community construction. Community beta diversity patterns are the result of a mixture of ecological (e.g., climate patterns and soil nutrients) and evolutionary processes. This study combined plant resource needs with how they respond to natural recovery times in order to provide useful knowledge to protect biodiversity, the nutrient cycle, and the function of restoration ecology. [ABSTRACT FROM AUTHOR]

Peatland and forest ecosystems located in the Bieszczady Mts. (Carpathians, Central Europe) have been affected by human activity since the Neolithic, with this impact intensifying over time. We conducted long‐term studies to: (i) determine past peatland and forest development and current ecological state; (ii) assess the role of different factors that influenced ecosystem development over the last 3750 years; and (iii) determine natural reference conditions as a basis for the restoration of degraded mountain bogs and forests in the region. High‐resolution multi‐proxy palaeoecological analyses (plant macrofossils, pollen, testate amoebae, macro and microcharcoal, peat stoichiometry and stable isotopes), supported by radiocarbon dating, were performed on peat cores from an ombrotrophic peatland. Our study revealed that the peatland and forest ecosystems have been impacted by both climate change and human activity (fires, deforestation, and grazing) over the past 3750 years and that massive deforestation took place 400 years ago. Changes in forest composition led to the intensification in erosion between 3700–1500 cal. BP and over the past 350 years. Drainage resulted in hydrological disturbances but did neither stop the peat formation process nor decreased the abundance of species forming the natural peat plant communities indicative of oligotrophic conditions. However, hydrological disturbances shifted peat plant composition to dry‐adapted species (e.g. dwarf shrubs, Pinus sylvestris). Average water level depth fluctuated between ca. 10 and 25 cm over the last 3750 years; thus these are conditions that could be considered as hydrological reference for restoration measures. Our approach to identify natural reference conditions may be expanded to peatlands from other temperate mountain ranges. [ABSTRACT FROM AUTHOR]

Glacier forelands are among the most rapidly changing landscapes on Earth. Stable ground is rare as geomorphic processes move sediments across large areas of glacier forelands for decades to centuries following glacier retreat. Yet, most ecological studies sample exclusively on stable terrain to fulfill chronosequence criteria, thus missing potential feedbacks between geomorphic disturbances and vegetation colonization. By influencing vegetation and soil development, such vegetation‐geomorphic disturbance feedbacks could be crucial to understand glacier foreland ecosystem development in a changing climate. We surveyed vegetation and environmental properties, including geomorphic disturbance intensities, in 105 plots located on both stable and unstable moraine terrain in two geomorphologically active glacier forelands in New Zealand and Switzerland. Our plot data showed that geomorphic disturbance intensities permanently changed from high/moderate to low/stable when vegetation reached cover values of around 40%. Around this cover value, species with response and effect traits adapted to geomorphic disturbances dominated. This suggests that such species can act as "biogeomorphic" ecosystem engineers that stabilize ground through positive feedback loops. Across floristic regions, biogeomorphic ecosystem engineer traits creating ground stabilization, such as mat growth and association with mycorrhiza, are remarkably similar. Nonmetric multidimensional scaling revealed a linked sequence of decreasing geomorphic disturbance intensities and changing species composition from pioneer to late successional species. We interpret this linked geomorphic disturbance‐vegetation succession sequence as "biogeomorphic succession," a common successional pathway in unstable river and coastal ecosystems across the world. Soil and vegetation development were related to this sequence and only advanced once biogeomorphic ecosystem engineer species covered 40%–45% of a plot, indicating a crucial role of biogeomorphic ecosystem engineer stabilization. Different topoclimatic conditions could explain variance in biogeomorphic succession timescales and ecosystem engineer root traits between the glacier forelands. As glacier foreland ground is widely unstable, we propose to consider glacier forelands as "biogeomorphic ecosystems" in which ecosystem structure and function are shaped by geomorphic disturbances and their feedbacks with adapted plant species, similar to rivers and coasts. [ABSTRACT FROM AUTHOR]

Carbon (C), nitrogen (N), phosphorus (P) and potassium (K) are the main nutrient elements widely found in soil, litter and leaves, and their stoichiometric ratios are important indicators of ecosystem functions. However, there is little research on the effects that nutrient cycle and vegetation succession have on leaf, litter and soil nutrients and stoichiometric ratios, especially in the fragile karst areas. To reveal the nutrient cycling characteristics and ecosystem stability mechanism during vegetation succession, leaf, litter and soil samples were collected from the herbaceous community (HC), shrub community (SC), secondary forest community (SF) and primary forest community (PF) in a typical karst area at growth and senescence phases. The results showed that the nutrient contents and stoichiometric ratios of leaf, litter and soil in the main layers of each community were significantly different at the growth and senescence phase. The utilization efficiency of N in the leaves of the main layers of each succession community first decreased and then increased at different growth stages, and the utilization efficiency of P increased but the reabsorption rates of N and P showed a continuous decreasing trend. In addition, there was a significant allometric relationship between N and P contents in plant leaves during the growth phase. More importantly, the internal stability of N content in plant leaves was higher than the P content, suggesting that vegetation succession significantly affected leaf, litter and soil nutrient contents and their stoichiometric ratios in our study region. The strength of the relationship between them reflects the inheritance and co–variation of nutrient content to a certain extent, and the differences in the strategies that different species in the community use to adapt to the fragile karst environment. This study concludes that plants in the karst region mainly improve their P utilization efficiency to adapt to low phosphorus stress in soil and ensure the normal physiological and biochemical responses in the process of vegetation succession. [ABSTRACT FROM AUTHOR]

Peberholm is a constructed Danish island in the Øresund strait. It was primarily constructed by calcareous clay from the sea floor, and is traversed by a highway and a railway. Being constructed from material without a seed bank, Peberholm constituted a good opportunity to study primary succession in an anthropogenic context. In this study, data from a survey of the vascular plant community of Peberholm was studied. The data span over a 22 year‐period, between 1999 and 2020. The development of the flora was analysed with regards to indicators for environmental factors and vegetation types, as well as occurrence of alien species or species of conservation concern. Peberholm experienced a rapid succession during its first five years. The effects of the initial ground disturbance quickly wore off, resulting in a relative decline in plant communities associated with ruderal land. These highly anthropogenic habitats were replaced with grasslands. The shrubification also began early on. The rapid initial changes were then replaced with a much slower but also more continuous change, resulting in the development of both more natural grasslands and an increased shrubification. Although several rare or threatened species colonized Peberholm from the beginning, the conservation value of the flora on a whole increased during the succession process of forming more natural vegetation types. The succession process demonstrated at Peberholm has more in common with the succession at urban soils than with naturally occurring primary succession. [ABSTRACT FROM AUTHOR]

Environmental changes are impacting river systems worldwide. These arise from factors such as flood magnitude–frequency changes, direct human management interventions, inadvertent human impacts on sediment supply and fluvial regimes and landscape‐scale changes in climate. Historical and active metal mining is significant in this regard. Here, we investigate morphodynamic changes within a reach of the River Ystwyth, Wales, since 1845. We analyse historical and contemporary information derived from maps, river flow records (1962–2021), metal analyses of sediment samples (1970s and 2021), ground geomorphological surveys (1970s and 1986–1987) and remotely sensed imagery (2001–2021) to investigate changes during a period of active metal mining followed by a century of post‐mining recovery. During the studied period, an initially meandering river was transformed into a braided one, subsequently reverting to a single sinuous channel. Sinuosity reduced from 1.31 in 1845 to 1.09 in 1982 before recovering to 1.39 in 2019. Inversely, the braiding index reduced from a maximum of 2.0 in 1987 to 1.5 in 2021. Evolution in planform was associated with a change from expansive bar formation and avulsion under braided conditions to lateral bar accretion and associated bank erosion along a sinuous single channel. The initial 19th‐century channel pattern and floodplain instability seems to have been related to mining sediment toxicity effects rather than a response to high sediment volumes, with recent recovery and channel style reversion being attributable to vegetation encroachment and biomass stabilization of the floodplain. Causal factors of recent recovery appear to be colonization by gorse (Ulex europeaus) in the absence of physical control measures and a reduction in grazing by the native rabbit population because of a disease‐induced decline in their numbers. These results highlight the importance of riparian vegetation in addition to sediment balance and hydrological processes in controlling fluvial responses to environmental changes. [ABSTRACT FROM AUTHOR]

Purpose: A general understanding of the influence of different plant species on soil quality improvement under drought stress is vital for planning the restoration of degraded land resources, especially in the context of global warming. Methods: In this pot study, we planted Setaria viridis, Stipa bungeana, and Bothriochloa ischaemum, which are typical grass species on abandoned farmland, succeeded by grassland, in the Loess Plateau of China, under optimal soil water conditions and under water deficit (i.e., 80% and 60% of soil field capacity, respectively). Rhizosphere soil samples of the three grass species were collected after 76 days of growth, and 21 soil properties were determined as potential indicators of soil quality. Four rhizosphere soil quality indices (SQI) were computed using linear/nonlinear scoring functions and additive/weighted additive methods by the selected minimum dataset (MDS). Results: L-leucine aminopeptidase, cellobiohydrolase, phenol oxidase, total phosphorus, available phosphorus, nitrate nitrogen, water-soluble nitrate nitrogen, and water-soluble ammonium nitrogen constituted the MDS for SQI calculation. The nonlinear weighted additive index best discriminated the effects of grass species under drought stress. Rhizosphere SQI did not significantly differ among the three grass species under optimal water conditions, but drought stress exerted a positive effect on rhizosphere SQI, which was significant for S. viridis. Conclusion: Short-term drought stress increased rhizosphere SQI, especially at the preliminary succession stages. Furthermore, the relatively stable rhizosphere SQI of plant species at the later-successional stages suggests that the later-successional plant species resisted drought stress better; this aspect warrants further investigation. [ABSTRACT FROM AUTHOR]