Generalist rather than specialist ants drive the recovery of ant-mediated plant protection across secondary succession in a dry tropical forest

ABSTRACT Wealth maximization by forest landowners in the United States has evolved since European settlement, in part due to markets for forest-based goods that existed at each point in time and the perception of landowners regarding their ability to generate revenue by supplying these markets with materials grown or found. Early forest investment activity had a few objectives: harvest timber for a growing society and provide revenue for landowners; many forested lands were converted to agricultural uses. Other lands were abandoned after forest harvest activities and left to naturally regenerate through secondary succession processes because of the inability of landowners to pay property taxes. However, management of forest lands in the United States as a business opportunity has created wealth for forest landowners, helped produce products for society, and aided in stabilizing the area covered by trees. Opportunities to generate revenue from other natural capital resources of forested landscapes have arisen. These opportunities often, however, require information, effort, or financing beyond the reach of smaller forest landowners.

Secondary succession in the Caatinga is composed of species that persist throughout all chronosequence

The great diversity of anaerobic digestion (AD) microbiomes indicates high redundancy and flexibility in the assembly of the community. Moreover, AD microbiomes are frequently subjected to disturbances during start-up and operation that require (re)assembly. We tested the reproducibility of secondary succession and AD community assembly mechanisms using a pre-assembled microbiome that was subjected to intense disturbances. Microbiome diversity and functions were followed in replicate mesophilic batch digesters initiated with multiple stressors, including high feed-to-inoculum ratio and many foreign species. Three 10 L batch digesters were derived from a single long-term CSTR digester pre-adapted to poultry litter feedstock and operated in parallel. Physicochemical parameters (methane, acetate, propionate, butyrate, pH, N-NH3, COD) were measured. Metagenome samples were used to assess diversity and functions. Three performance phases were found along the successional gradient: (1) methane inhibition, (2) high methane production, and (3) low methane plateau. The inventory of species (>1600) remained nearly the same, however the relative abundance of species, families, and functions changed during each successional stage. Syntrophic bacteria peaked in abundance during the mid-succession, high methane stage. Succession of overall KEGG functions was highly similar although species and carbohydrate functions diverged during late succession, suggesting diversity of niche partitioning during degradation of recalcitrant organic matter. We estimated the relative contributions of stochastic and deterministic processes and found a shift in the balance during succession. Early succession was not dominated by either dispersal or selection while late succession was dominated by variable selection. In conclusion, methane production recovered following severe (non-lethal) disturbance in a pre-adapted digester microbiome through a reproducible community assembly pathway that shifted toward deterministic, variable selection over time.

Post-abandonment management strategies influence future soil organic carbon storage and water resources.

Ecosystem multifunctionality(EMF) refers to an integrated measure of an ecosystem's capacity to perform multiple co-occurring functions. However, change the multi-factor driving mechanism of EMF during poplar-birch secondary forest succession are still poorly understood. Using a space-for-time substitution approach, this study examined four succession stages (early, middle, middle-late, and late) of poplar-birch secondary forests in the Northern Hebei Mountains. It investigated soil physicochemical properties, plant productivity, quantified functional indices and explored the multi-factor driving mechanisms for changing EMF. The results showed that stand and litter (stand volume, litter biomass, litter carbon stock), soil nutrients (organic matter, total nitrogen, available nitrogen, available phosphorus) and soil enzymes (cellobiohydrolase, dissolved organic carbon, n-acetyl-β-D-glucosaminidase and leucine aminopeptidase) significantly elevated as the succession progressed (p < 0.05). Compared with the early stage, the carbon, nitrogen, and phosphorus function indices and the ecosystem multifunctionality index significantly increased by 169%, 287%, 210% and 216% (p < 0.05), respectively. Structural equation modeling (SEM) indicated that increased litter biomass enhanced total soil nutrients, which in turn stimulated soil enzyme activity, ultimately promoting EMF as succession advanced. Notably, total soil nutrients were key factors driving ecosystem multifunctionality enhancement. Overall, plant productivity and soil fertility increased during secondary forest succession, thereby strengthening ecosystem multifunctionality, which provided scientific support for the sustainable development of forest EMF.

Carbon (C) uptake in regrowing secondary forests increasingly dominates landscape-scale C dynamics in the tropics. Understanding the recovery trajectories of net primary productivity (NPP) and C allocation, along with the underlying demographic and functional drivers of biomass recovery, is therefore critical. Using a space-for-time setup spanning five successional stages, we showed that - for forests in the Yoko reserve, in central Africa - C fluxes related to recruitment and mortality decreased along succession, alongside a gradual transition from a forest with high stem density and acquisitive species to one with lower stem density and more conservative species. In the first decade of succession, NPP allocation shifted from being dominated by woody productivity to canopy productivity. Higher tree mortality in early succession counterbalanced the higher woody NPP, producing a relatively constant net woody C sink along succession. While being positive, this woody C sink was small, suggesting a slow but steady recovery to old-growth aboveground C stocks ranging between 171 and 238 Mg C ha-1. Overall, our findings demonstrate the potential of secondary forests in the Congo basin to mitigate climate change, but also emphasize the need to conserve old-growth forest C stocks and expand long-term observational data to better constrain regional C recovery dynamics.

Understanding forest carbon sequestration is crucial for predicting and managing the carbon cycle, yet we lack evidence for whether, when and how the carbon sink in tropical forests recovering from land use change is nutrient limited. Here we show how the tropical forest recovery rate responds to experimental nutrient manipulation over a secondary succession gradient in a naturally recovering Central American landscape. Nutrient limitation of aboveground biomass accumulation shifts from strong nitrogen limitation in young forests to no evidence of nitrogen or phosphorus limitation in older secondary or mature forests. Nitrogen addition increases aboveground biomass accumulation by 95% in recently abandoned pasture and 48% in 10-year-old forests. Conversely, we observe no influence of nitrogen on older forests and no evidence of phosphorus limitation at any stage. If our findings of nitrogen limitation extend to young tropical forests globally, nitrogen could prevent the sequestration of 0.69 (0.47-0.84) Gt CO2 each year.

Abstract Forest structural complexity is an essential determinant of forest ecosystem functions and biodiversity. The natural dynamics of structural complexity of tropical forests remain largely unexplored, especially for naturally regenerating forests during secondary succession. Better understanding the trajectories of forest structural complexity recovery is crucial to inform the development of forest landscape restoration strategies and to predict the reassembly of ecological networks during secondary succession. Here, we investigate the recovery of forest structural complexity during secondary succession following land use abandonment in a human‐modified landscape in Ecuador. We employ a terrestrial laser scanning‐based index of forest structural complexity to quantify the three‐dimensional vegetation structure of agricultural lands (cacao plantations and pastures, n = 10), naturally regenerating sites ( n = 30) and primary old‐growth forests ( n = 16) along a chrono‐sequence of secondary succession. We find that sites recovering after land use abandonment attain levels of forest structural complexity comparable to old‐growth forest within 40 years. Changes in forest structural complexity along the successional gradient follow a saturating pattern, with rapid increases in the first years and only minor potential for further increases after 40 years. Increasing tree species diversity during secondary succession is identified as a major driver of the recovery of forest structural complexity. Using a structural equation modelling approach, we find that the effects of tree species diversity on forest structural complexity are mediated by its effects on vertical stratification, as the effective number of canopy layers increases with increasing recovery age. Synthesis . Our results suggest that land use abandonment and subsequent natural regeneration facilitate the restoration of forest structural complexity in human‐modified neotropical landscapes. Increasing tree species diversity during secondary succession is an important driver of forest structural complexity recovery. To better understand the role of tree species diversity in shaping the three‐dimensional structure of recovering forests, future studies should address the role of intra‐ and interspecific differences in crown morphology and functional traits as potential drivers of forest structural complexity.

Tropical grasslands in South Assam, northeast India originated as a result of secondary succession on the abandoned lands after cultivation or deforestation. The grasslands are dominated by Imperata cylindrica and maintained under fire management as a customary practice. The rice farming communities exploit these grasslands for obtaining thatch leaves. This paper therefore, explores the culturally old grassland in Dorgakona, South Assam, northeast India and the impact of fire regime on its herbaceous flora and grasses. It presents 1) vegetation study to generate quantitative information on analytical characters of grasses and associated species and 2) an analysis of life-forms, biological spectrum and phenology of the grassland herbaceous flora followed by citing the significance of the current vegetation studies. Imperata cylindrica was dominant based on IVI (132. 27 and 141.68) for the burnt and unburnt plots respectively. Borreria pusilla (co-dominant) with IVI of (63.10 and 29.75) was fire dependent species as revealed by the data sequentially placed for burnt and unburnt plots respectively. Fire induced grasses (Chrysopogon aciculatus and Sacciolepis indica), tuber (Colocasia esculenta) were restricted to burnt plot. Multifold proliferation in the therophytes and cryptophytes occurred over Raunkiaer’s spectrum assigned with thero-cryptophytic climate. Plant phenological study revealed sequential changes in the phenoogical events. The tropical grasslands are predominated with fire resistant I. cylindrica and are adapted to the indigenous management procedures. It is recommended that the outcome of this study will generate valuable database for future researches on the degraded lands.

The southern Patagonian steppe grasslands are fundamental ecosystems for biodiversity conservation and the maintenance of productive activities, although they are highly sensitive to anthropogenic disturbances. This study assessed vegetation cover recovery along a section of the Dungeness–Daniel Este 8" hydrocarbon pipeline, Magallanes Region (Chile), to determine the ecological resilience of coironal grassland nearly three decades after its construction. Vegetation characterization was performed using 72 modified Parker plots of 1 m² (2 × 0.5 m). In each plot, the presence and cover of all vascular and cryptogamic species were recorded, together with litter, standing dead vegetation, bare soil, stones, and feces. Thirty-six plots were placed randomly along the pipeline axis (flow line), and thirty-six in a non-intervened reference area located 20–25 m away but under grazing use. Species richness, vegetation cover, bare soil, and diversity indices (Shannon and Pielou) were calculated. Data were analyzed using non-parametric tests (Kruskal–Wallis) and multivariate analyses (PCA, ANOSIM, and SIMPER). A total of 66 species were identified, 81.8% of which were native. Vegetation cover reached 67.8% along the pipeline and 73.9% in the reference area, exceeding the 60% threshold required by the Environmental Qualification Resolution. No significant differences in richness or diversity were detected, indicating a comparable floristic structure. Dominant species Festuca gracillima and Baccharis magellanica accounted for 40% of total dissimilarity, together with colonizing species such as Acaena magellanica and Rumex acetosella, indicating an advanced stage of secondary succession. The occurrence of Chloraea magellanica, a rare orchid with restricted distribution, highlights the presence of functional microhabitats and recovering mycorrhizal associations. Results demonstrate that, despite arid conditions and grazing pressure, vegetation has re-established its structure and function through passive restoration processes. This case provides empirical evidence that underground pipelines, when maintaining ecological connectivity, can be integrated into the landscape without significant biodiversity loss.

Secondary succession of abandoned agricultural land is a long-term process, shaped by numerous biotic and abiotic factors. One stage in this process is the encroachment of pioneer tree species, among which the black cherry Padus serotina is increasingly common. This invasive species is widespread in temperate forests in Europe and is beginning to colonize open habitats, including fallow lands. In this study, we evaluated the effects of P. serotina on floristic composition, vegetation, and species diversity. Ten fallows in Lower Silesia (SW Poland) were selected. Within each field, five study plots invaded by P. serotina and five without this species were established. Botanical composition and area covered by individual plant species were determined in total of 100 plots. Our results indicate that the P. serotina seedlings and saplings have the strongest impact on species composition. The increase in P. serotina cover in the herb layer is accompanied by a reduction in the spread of expansive species such as Calamagrostis epigejos and Solidago gigantea. The low thickets formed by P. serotina provide perching sites for birds and facilitate seed dispersal, which promotes the development of multispecies shrub communities and enhances species diversity in study fallows at the current stage of succession.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-29099-8.

White-tailed deer (Odocoileus virginianus) are known to alter the composition of plant communities and the course of secondary succession. We present 18 years of data from a long-term deer exclosure experiment near Ithaca, NY, USA, to evaluate seedbank dynamics and the resulting aboveground community. Seedbank data were collected annually from 2005 to 2021 through a germination assay in which 280,674 emerged seedlings were identified. Aboveground data were collected from 2019 to 2022. Across all years, deer increased Shannon-Wiener diversity of seeds germinated from the soil by 8% relative to exclosure plots but did not affect abundance or species richness. Deer altered seedbank composition but not the percentage of biennial/perennial (vs. annual) or native (vs. non-native) species in the seedbank. Deer had little effect on aboveground plant communities (total cover, diversity, percentage biennial/perennial, percentage native) in 2019 or 2022. Nonetheless, deer reduced the abundance of woody plants by 50% and only the exclosure treatment had trees exceeding 1 cm diameter at breast height after 16 years. Although seedbank and aboveground plant communities changed over the study period, there was generally no interaction between the effects of exclosure treatment and year. Overall, our findings show that deer increased seedbank diversity, altered seedbank community composition, and suppressed woody plants aboveground. These changes are likely to impact the process of secondary succession. Increased seedbank diversity might increase the feasibility of passive restoration, whereas suppression of woody plants would delay forest recovery.

The article discusses the issue of geological and ecological heritage of the Second World War in Warsaw. It analyses the first, unrealised plans to create a “ruin preserve” in order to conserve war damage, and the projects to build a rubble mound as monument to the heroes of Warsaw. However, these ideas were unintentionally materialised in the form of a rubble pile, which many years later was recognised as the Warsaw Uprising Mound. Presently, it is overgrown with a secondary succession forest, creating third landscape. It has been included in the monumental layout and is a testimony to the development of spontaneous vegetation that has colonised the rubble substrate over the years. The Mound, initially an unwanted legacy of human war activity, creates anthropogenic geological layers of the city, thus blurring the dichotomy between natural and cultural heritage in the Anthropocene era.

Effects of stand structural changes on vegetation carbon sequestration capacity during secondary succession in subtropical evergreen-deciduous broadleaved mixed forests in central China.

Taxonomic assembly and trait partitioning contribute comparably to soil invertebrate functional diversity along secondary succession in high-elevation plateau ecosystems

Agricultural land abandonment is considered one of the most important local-scale causes of landscape change. Simultaneously, the leading consequence of abandonment is the process of natural revegetation, also known as secondary succession of communities, which ultimately results in the formation of secondary forests. This study investigates the dynamics of vegetation succession across five abandoned agricultural land plots, located in different morphological districts of Lithuania’s landscape. Various research methods were integrated to determine succession patterns: a review of scientific literature, analysis of orthophoto maps and Sentinel-2 multispectral satellite images, together with the calculation of spectral vegetation indices, including EVI and NDWI. Moreover, changes in vegetation condition values were compared with the influence of natural conditions in different research areas. The findings of this study indicate that in all analyzed land plots, vegetation succession took place in a directional manner, reaching the secondary forest stage within several decades. In the early stages, the development of woody vegetation depended on the abandoned land plot’s position relative to the woodland. The condition of vegetation improved in all plots during the 2017-2024 growing seasons, but differed in the scale and speed of succession. Most intense succession occurred in the Middle Aukštaičiai sparsely forested agrarian uplift benchmark, while the least intense succession occurred in the Middle Dzūkai forested agrarian lake district benchmark. The rate of vegetation change in the benchmark of Lėvuo upper course-Šventoji lower course forested agrarian plain was limited by leaching processes in the loamy deposits. The slowest changes were observed in the Vilnija Dzūkai forested agrarian uphill and Eišiškės sparsely forested agrarian uplift (plateau) benchmarks. These differences between abandoned land plots were mainly determined by a complex of edaphic conditions, topography, and former agricultural activities. Precipitation amount and temperature were statistically insignificant for the changes in the vegetation condition, except for the Eišiškės sparsely forested agrarian uplift (plateau) plot, where a statistically significant positive correlation between green biomass growth and rising temperature was detected. Simultaneously, a statistically significant negative correlation between vegetation condition changes and precipitation was found in the Middle Aukštaičiai sparsely forested agrarian uplift and the Lėvuo upper course-Šventoji lower course forested agrarian plain benchmarks.

The accumulation of microbial-derived organic carbon in soils during long-term vegetation succession represents a key pathway for long-term soil carbon stabilization. Yet, the role of soil microfauna in regulating microbial carbon dynamics remains poorly understood, particularly across divergent successional trajectories (primary vs. secondary successional gradients). We investigated nematode-microbe interactions influencing carbon dynamics in primary (glacial retreat) and secondary (post-disturbance) successional chronosequence on the eastern Qinghai-Tibet Plateau, to identify context-dependent mechanisms underpinning soil carbon formation and dynamics. Both successional types displayed an 'S-shaped' trajectory of carbon dynamics, initially rising from early to intermediate stages, declining subsequently, then increasing again in late stages, with microbial necromass (quantified by amino sugars) dominating the carbon pool, especially in later stages. In primary succession, characterized by nutrient limitation and slower soil development, nematode-mediated shifts in microbial community composition and functional gene expression, particularly reductions in growth-related and decomposition genes, enhanced microbial turnover and necromass accumulation. In contrast, in phosphorus-limited soils of secondary succession, where nutrient availability and disturbance history play a larger role, declining omnivorous nematodes modulated microbial gene expression to enhance carbon fixation and constrain decomposition under phosphorus-rich conditions. Soil pH consistently acted as the primary abiotic factor influencing microbial communities across both successional sequences, explaining up to 29% of variation in microbial gene profiles. These findings position microbial necromass accumulation as a central pathway for carbon sequestration and identify nematodes as context-dependent regulators of microbial carbon processing. Our study underscores the need to integrate both soil microbial and faunal dynamics, along with key physicochemical properties, into ecosystem models to improve predictions of carbon-climate feedbacks across successional landscapes.

Secondary succession of a seasonally dry tropical forest is taxonomically stochastic but functionally deterministic

Plant-soil feedback driven by root-associated fungal communities accelerates the secondary succession of bare saline-alkaline grassland patches