Recovery of forest and soil attributes during dry and wet secondary tropical forest succession

The Cladonio–Pinetum association is among Europe’s most endangered dry, sandy forest communities and is highly sensitive to microclimate and edaphic shifts. We quantified how seasonality and microhabitat (psammophilous grasslands vs. pine forests) modulate physiological traits of the dominant terricolous lichens Cladonia mitis and Cl. uncialis in Bory Tucholskie National Park (north-central Poland). From September 2022 to September 2023 we monitored six permanent sites, recording light, temperature, moisture, and soil chemistry, and seasonally measuring maximum quantum efficiency of PS II ( F V / F M ) and concentrations of usnic acid, total chlorophyll ( a + b ), lutein, and β-carotene. Usnic acid was quantified by UHPLC–PDA; chlorophylls/carotenoids by UHPLC–ESI-QqQ-MRM. F V / F M peaked in winter (0.77 ± 0.019) and reached a summer minimum (0.59 ± 0.05) in both species, consistent with photothermal and drought stress. Usnic acid showed the opposite pattern, peaking in summer (31.66 mg g⁻¹ DW) and remaining ∼2 × higher in Cl. mitis across seasons; beyond certain concentration levels, higher usnic acid content was associated with a downward trend in F V / F M . Total chlorophyll differed between species and was consistently higher in Cl. mitis ; β-carotene showed seasonal variation, whereas lutein remained stable. Multiple regression identified light, air temperature, soil moisture, pH, and nitrogen as the main predictors of both F V / F M and usnic acid, explaining > 40% of their variance. Our results demonstrate that an integrated suite of chlorophyll fluorescence, pigment profiles, and secondary metabolite levels provides a sensitive early-warning system for detecting habitat degradation in Scots pine lichen forest. Managing canopy openness and curbing nutrient enrichment emerge as key conservation levers for sustaining these communities. • Photosystem II efficiency peaks in winter, dips in summer; microclimate–driven. • Usnic acid varies by season and lichen species. • Total chlorophyll is stable; β-carotene peaks in summer stress; lutein constant. • Physiological and environmental metrics are a tool to assess Cladonio-Pinetum state.

Estimating the number of insect species on Earth is a daunting challenge. The current consensus estimate-about six million species-is likely far too low, as we will show. Our estimate of the global number of insect species rests on a sample of more than 1,600,000 DNA-barcoded insect specimens representing 53,945 species from 15 "core" Malaise traps deployed in dry forest, cloud forest, and rainforest ecosystems of the Área de Conservación Guanacaste (ACG) in Costa Rica. Even this massive sample fails to reveal the full extent of ACG insect species richness. To estimate total ACG insect richness, we adjust the observed count of insect species by an "undersampling ratio," computed for a hyperdiverse subfamily of parasitoid wasps (Braconidae: Microgastrinae). The ratio compares microgastrine richness from the core Malaise traps to a lower-bound estimate of true microgastrine richness-including undetected species-based on 21,669 specimens from three sources: the 15 core Malaise traps, 15 "peripheral" Malaise traps spanning all three ecosystems, and 11,373 DNA-barcoded specimens reared from some 1,500 species of microgastrine-parasitized caterpillars (Lepidoptera). To estimate global insect richness, we apply Earth/ACG ratios for tree species and several animal taxa to upscale our estimate of ACG insect richness (nearly 333,000 species). Adopting conservative assumptions, we reach an estimate of 14 to 20 million insect species on Earth, depending on the upscaling group-two to three times the current consensus estimates. Upscaling instead from a point estimate of ACG richness with a wide CI, global estimates reach nearly 30 million species.

Land-use changes in tropical dry forests (TDF) have rapidly reduced native vegetation, disrupting gene flow dynamics of tree species. Bursera cuneata is a co-dominant TDF tree in central Mexico, which is threatened by habitat loss and overexploitation. We investigated landscape drivers of functional connectivity of B. cuneata across scales to inform species conservation efforts. We genotyped 227 B. cuneata individuals from 33 populations across five hydrological basins: covering western, central, and southern Mexico, at 10,499 single-nucleotide polymorphism (SNP) loci. We examined spatial patterns of genetic structure among hydrological basins and the landscape correlates of gene flow. We applied gravity models that incorporated within-site (i.e., local conditions within populations; slope and east aspect) and between-site (terrain roughness, habitat suitability, and habitat cover) factors associated with B. cuneata gene flow. Clustering analyses showed genetic structure among basins, with higher differentiation in more isolated regions. Gravity models revealed that functional connectivity is a scale-dependent process. Specifically, terrain roughness was the primary factor of connectivity at finer scales (1000-3000 m), while TDF cover became the main driver at regional scales (>4000 m). We recommend protecting and prioritizing crucial TDF remnants to maintain large-scale gene flow by integrating urban natural parks as important links to prevent genetic isolation between urban and rural populations.

Soil microorganisms are central to ecosystem functioning, yet how habitat degradation affects their community structure and functional potential in dry Afromontane forests (DAFs) remains poorly understood. This study investigated soil prokaryotic communities across five habitats representing a disturbance gradient in Ethiopian DAFs: Church forest, State forest, Community-managed forest, Shrubland, and Cropland. Using next-generation sequencing, we examined prokaryotic community composition, diversity, assembly processes, and predicted functional profiles. Actinobacteriota and Crenarchaeota were more abundant in less disturbed forests, whereas disturbed habitats showed shifts toward taxa associated with stressed conditions. Alpha diversity was lower in Church and State forests than in shrubland and cropland, indicating environmental filtering and dominance of habitat specialists. Community composition differed significantly among habitats and was associated with soil properties, stand attributes, and indicator trees. Deterministic processes explained most community turnover (81%), indicating strong environmental structuring, with homogeneous selection more evident in forests and mixed deterministic-stochastic processes in disturbed habitats. Predicted functional profiles suggest shifts in nitrogen-related processes, particularly ammonia oxidation and nitrification, although not directly measure microbial activity. Overall, habitat degradation is associated with changes in prokaryotic community structure and assembly, highlighting the importance of conserving intact forests and supporting restoration efforts in dryland ecosystems.

BackgroundBiodiversity is at increasing risk, and amphibians are the most threatened vertebrate class, with 40.7% of species globally at risk. For amphibians, the primary cause for their decline is habitat loss. The scale of this global issue becomes most evident in so-called deforestation hotspots, such as the Chiquitano Dry Forest in Bolivia, which harbours a highly diverse fauna and flora with many species still awaiting formal description. Only recently, the frog Oreobates chiquitanus has been described from a single location within this forest. Since then, it was discovered at only two additional sites. An ongoing logging initiative at the type locality led to the deforestation of the sampling site, even before the species was formally described. Ongoing logging activities in the vicinity of all known sites raise questions about the species’ fate. Here, we provide a comprehensive genetic definition of the species and try to assess the genetic diversity and conservation value of the type population.ResultsWe sequenced all available type specimens of Oreobates chiquitanus, providing a reference genome from one of the paratopotypes and mitochondrial assemblies for all type specimens. We further show that all known populations of this species are near recent logging initiatives. The reconstruction of the demographic history indicates that the population was recovering from a dip roughly 300kya. The estimates of relatedness and heterozygosity imply a genetically vital population.ConclusionsThis study exemplifies the importance of collaboration of natural history collections and genomic initiatives like TBG (Translational Biodiversity Genomics) for a better understanding of the anthropogenic impacts in times of global change, to identify and describe biodiversity, to raise awareness, and inform potential conservation measures. We not only provide a comprehensive and permanent molecular definition for O. chiquitanus but also assess the genetic diversity of the population. Therefore, this study provides an important baseline for future studies of genetic erosion in this species. Furthermore, it illustrates the risk of biodiversity loss in the Chiquitano Dry Forest and signifies the need for conservation efforts.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12864-026-12984-5.

Although previous studies have suggested that lianas exhibit superior growth compared with trees during dry seasons, their strategies for acquiring water remain poorly understood. This study investigated the water uptake depth and above-ground functional traits of 10 liana species and 11 tree species coexisting in a seasonally dry tropical evergreen forest in Cambodia. Using stable oxygen isotopes, we estimated dry-season water uptake depths and compared five functional traits, including specific leaf area, leaf nitrogen and phosphorus content, stable carbon isotope ratio (δ13C) of leaves and wood density. Both lianas and trees absorbed water mainly from middle to deep soil layers, with no significant difference in water uptake depth. We found substantial variation in water uptake depth even within the same life-form, with some species relying on shallow soil water and others accessing much deeper sources, indicating diverse water acquisition strategies during the dry season. With slightly higher specific leaf area and lower wood density, lianas showed a relatively acquisitive carbon- and nutrient-use strategy compared with trees; however, there was no significant difference in water-use efficiency, as represented by leaf δ13C. Patterns of trait coordination among multiple organs differed between lianas and trees. In lianas, deeper water uptake was positively correlated with less negative leaf δ13C, whereas in trees this relationship was negative as well as weak. This divergence highlights different functional strategies even under similar environmental pressures. Our findings underscore the fact that lianas did not consistently use deeper water or show higher water-use efficiency than trees in this ecosystem. Instead, trait variations and the coordination between above- and below-ground traits may help explain the success of lianas in seasonally dry environments.

ABSTRACTTo better understand successional changes and drivers of changes in forests, we must (1) test assumptions of successional studies and (2) quantify patterns in species and functional traits in stands varying in successional age. Successional changes are commonly approximated by quantifying changes along chronosequences, or space‐for‐time substitutions. These assumed successional patterns, however, are rarely tested through longitudinal studies of individual sites. To identify drivers of successional trajectories and to address questions of deterministic vs. stochastic community assembly, species composition data must be supplemented with data such as species functional traits. We examined patterns in species composition and functional traits along a chronosequence of tropical dry forest (TDF) sites in North Key Largo, Florida in 1993. To test patterns identified along the chronosequence, we quantified longitudinal change in species and functional traits by remeasuring the sites in 2013. We tested the following predictions: (1) dynamic changes within sites in species composition and functional trait composition will corroborate a pattern indicated by the chronosequence; (2) a growth‐survival demographic tradeoff will be consistent with increasing dominance of evergreen species over the course of succession; and (3) forest succession will demonstrate convergence in both composition and function. As predicted, dynamic changes in species composition and functional traits within sites corroborated patterns quantified over the chronosequence, and species functional groups showed a growth‐survival demographic tradeoff between deciduous species early in succession and evergreen species late in succession. Surprisingly, however, although species composition converged late in succession, functional traits showed greatest divergence late in succession. We suggest that this divergence is due to functionally disparate evergreen and leaf exchanger species coexisting with high abundances for the first time late in succession, and to interspecific competition in an environment of limited resources late in succession. Synthesis. This is the first study in TDF to corroborate compositional and functional changes measured along a chronosequence with results of longitudinal measurements within sites. Additionally, this TDF ecosystem shows a rare successional pattern of convergence in species composition but divergence in functional traits, likely due to the coexistence of different functional groups and interspecific competition late in succession.

Progeny and provenance variation in germination performance and ex‑situ conservation potential of the endemic Talbotiella gentii in Ghana

Molecular detection of avian hemoparasites (Plasmodium and Haemoproteus) in resident and migratory birds from an urban fragment of tropical dry forest in northern Colombia.

Lianas are particularly abundant in seasonally dry tropical forests, where most species flower during the dry season. While hydraulic differences of vegetative organs between lianas and trees are well-documented, floral hydraulic strategies and their potential role in liana expansion remain unclear. To characterize divergence in floral water-use strategies between lianas and trees, we examined 24 floral traits related to water transport, storage, drought tolerance, and pollinator attraction in 16 liana and 16 tree species of Bauhinia s.l. from a tropical seasonal rainforest in Yunnan, China. Liana flowers exhibited greater petal vein density, stomatal density and size, flower mass per area, and drought tolerance than tree flowers, which showed higher saturated water content and hydraulic capacitance. Liana flowers exhibited a trade-off between hydraulic efficiency and safety, but trees did not. Life forms also differed in trait coordination linking hydraulic structure, function, and reproduction. Our findings reveal divergent floral hydraulic syndromes: lianas adopt structurally reinforced, drought-tolerant designs for canopy flowering under high vapor pressure deficit, while trees rely on internal water reserves to buffer water loss. This study provides the first organ-level evidence that divergent floral hydraulic strategies underpin reproductive success and may help explain liana dominance in seasonally dry tropical forests under climate change.

Abstract Background Prescribed fire is a common approach to reduce fuels and mitigate fire hazards. The accumulation of live and dead fuels following initial treatment means that repeated application of prescribed fire could be used to maintain this benefit. However, the effect of repeated prescribed fires is not well documented in many dry coniferous forests in the western United States. Here, we present observations of changes in live trees and surface fuels following two prescribed fires in dry coniferous forests in national parks of California. Results Changes in forest structure and accumulation of surface fuels were similar over time following initial-entry and second-entry fires. An exception was that repeated fires were associated with substantial reductions in stem density. There were smaller changes in live tree basal area and stem biomass. Conclusions Our results indicate that following initial-entry fires, subsequent burning maintained reductions in surface fuel loads without major inadvertent losses of live tree basal area and stem biomass, implying the survival of large trees.

This study evaluates the influence of harvesting methods and seasonal variability on the physicochemical and antioxidant properties of Tetragonisca fiebrigi honey produced in the tropical dry forest of Bolivia. Despite the growing interest in stingless bee honey, studies addressing the combined effects of seasonality and collection practices in this region remain scarce. Honey samples were collected during winter and spring using three approaches: conventional, optimized (based on good manufacturing practices), and direct racking from natural nests. Physicochemical parameters (pH 4.60–6.15; moisture 28–34%; water activity 0.69–0.75) and sugar composition (glucose 10.60–29.03 g/100 g; fructose 9.01–21.97 g/100 g; sucrose 0.70–3.23 g/100 g) showed variability primarily associated with season rather than harvesting method. Bioactive compounds exhibited a marked seasonal effect, with higher total phenolic content (up to 11.03 mg GAE/100 g), flavonoids (up to 23.08 mg QE/100 g), and antioxidant capacity (DPPH up to 1.33 mol TE/100 g; ORAC up to 25.93 mol TE/100 g) in spring samples. Multivariate analysis (PCA) revealed that honey variability is structured along bioactive and physicochemical axes, with samples obtained using the optimized method showing reduced dispersion and greater compositional consistency. These results indicate that while seasonality governs the compositional and functional properties of T. fiebrigi honey, improved harvesting practices contribute to reducing variability and enhancing product standardization. This study provides one of the first comprehensive datasets on Bolivian stingless bee honey and highlights its potential as a functional food, supporting the development of species-specific quality criteria and sustainable meliponiculture in tropical dry forest ecosystems.

ABSTRACT Michoacán possesses extensive forest cover yet has undergone rapid and sustained land use transformations driven by illegal logging and the expansion of the ‘avocado strip’. This study utilized Random Forest (RF) classification of Landsat imagery (1986–2025) to analyze landscape dynamics, identifying Near-Infrared (NIR) and Shortwave Infrared 2 (SWIR 2) bands as the most critical predictors. Change detection analysis revealed severe deforestation: dry forest declined by 4,344 km2 and evergreen forest by 1,698 km2, fueling a corresponding increase in exposed soils (3,270 km2) and croplands (2,158 km2). To assess ecological impacts, MaxEnt was employed to model the distribution of 35 vulnerable species (16 Near Threatened, 10 Vulnerable, and 9 Endangered) with Nighttime Land Surface Temperature in December emerging as the most influential variable. The biodiversity assessment (2000–2025) indicated that the Reddish Egret (Egretta rufescens) suffered the greatest loss of potential distribution area (exceeding 50%), while the Grey Plover (Pluvialis squatarola) and the Mexican Ground Pit Viper (Agkistrodon bilineatus) exhibited the greatest gains (approximately 50% increase). Given that these threatened ecosystems are poorly represented within current protected areas, these findings underscore an urgent need to integrate conservation strategies into regions undergoing intense agricultural conversion to mitigate further biodiversity loss.

A multitaxon biodiversity dataset from hemiboreal forests of different stand ages and management histories

Genetic diversity is critical for adaptability and resilience in response to environmental pressures, especially considering that human activities have drastically reduced natural populations. The endemic South American species, Myarcrodruon urundeuva (aroeira, Anacardiaceae), is found in the Caatinga dry forest, Brazilian Savanna, Atlantic Forest, and Pantanal Wetland biomes and has suffered from population reduction due to overexploitation of its wood. This study analyzed the genetic diversity of M. urundeuva across biomes and transition zones in Brazil using ddRADseq sequencing. Samples from 115 individuals and 12 populations were sequenced, generating 1427 informative SNP markers. The average allelic richness was 1227 for the 12 populations, and the inbreeding coefficient (Fis) ranged from 0.001 to 0.196. Notably, the Caatinga dry forest biome populations displayed a highly differentiated cluster. Clustering analysis indicates that genetic diversity patterns from other populations also show distinct population structures with significant differences in its distribution. These findings highlight the need for further research in northeastern Brazil and emphasize the importance of genetic diversity in conservation planning. Therefore, strategies that integrate conservation and molecular analyses are essential to safeguard M. urundeuva’s diversity and adaptability.

Vertical stratification and climatic seasonality influence the structuring of butterfly communities in tropical forests. This study assessed how vertical stratification (canopy vs. understory) and seasonal variation affect fruit-feeding butterfly (Nymphalidae) assemblages in a Brazilian tropical dry forest (TDF), and how these patterns relate to climatic variables and food resource availability. Sampling was conducted monthly over one year in the northern Espinhaço Range, within the Caatinga domain. Twenty 25 × 4m plots were established, each with two Van Someren-Rydon traps (understory at 1m and canopy at ≥ 6m). Monthly measurements included temperature, humidity, light, precipitation, and zoochoric fruit availability. We recorded 2,166 individuals from 51 species, with Biblidinae and Satyrini representing over 70% of the community. Hamadryas februa was dominant in the understory, while Biblis hyperia nectanabis prevailed in the canopy. Species composition differed between vertical strata, indicating niche partitioning likely driven by microclimatic variation. Temporal patterns also influenced diversity: species richness peaked during the hottest months, and abundance peaked in the driest month, about two months after the rainy season's peak. Subfamilies and tribes showed distinct seasonal peaks, suggesting temporal niche partitioning and reduced intergroup competition. Our findings highlight that vertical and seasonal gradients shape butterfly communities in TDFs. The high diversity and spatial-temporal dynamics observed emphasize the ecological value of the Caatinga and the need to consider vertical structure and seasonality in conservation strategies for TDFs, highly threatened and understudied ecosystems in Brazil.

ABSTRACT Studying temporal patterns provides insight into how climatic seasonality influences species composition, richness, and abundance. In tropical deciduous forests (TDF), where the effects of seasonality on phytophagous beetle communities have been documented, it is commonly assumed that these communities form two well-defined seasonal groups: one during the rainy season and another during the dry season. However, the response of these beetles to seasonality may be more complex than expected. We conducted monthly samplings over a year in a TDF in northern Morelos and analyzed the temporal variation in Buprestidae diversity and composition. We recorded 963 individuals from 83 species. As expected, the highest species richness and abundance coincided with precipitation peaks. However, beta diversity indicated high species turnover across months. The temporal structuring of Buprestidae diversity and composition throughout the year revealed three communities largely driven by specific plant phenophases. These seasonal shifts in community structure suggest that resource availability is fundamental in regulating Buprestidae assemblages. Changes in precipitation and temperature patterns due to anthropogenic factors, such as climate change, could alter the phenology of TDF and the emergence of these beetles, affecting their survival. Understanding these patterns is essential for predicting the impact of climatic phenomena on insect biodiversity.

The cosmopolitan genus Xylaria Hill ex Schrank (Ascomycota, Sordariomycetes), is the largest within the order Xylariales. While Xylaria species primarily exist as saprotrophs, they can also occur as endophytes or as phytopathogens. Specimens of Xylaria sp. were collected from a Fabaceae pod in the tropical dry forest in the state of Jalisco, Mexico. They were isolated and axenized in PDA culture medium. The genome of the strain was sequenced using Illumina NovaSeq technology and assembled. A phylogenomic approach was used to confirm its taxonomic position within the genus Xylaria. The resulting genome assembly is 51.93 Mb in size, featuring an N50 of 452,556 bp and a G + C content of 42.34%. Gene prediction with AUGUSTUS identified 11,238 protein-coding genes. Based on morphological and genomic evidence, these specimens are described here as a new species, Xylaria chamelensis sp. nov. Phylogenomic analysis incorporating available Xylaria genomes revealed that this strain forms a distinct, independent lineage within the Xylaria phylogenetic tree. Ultimately, these genomic data provide the scientific community with a valuable resource to advance genome-based taxonomy, unravel the molecular basis of plant-fungus associations, and further explore the diverse metabolism of the genus Xylaria across tropical and subtropical environments.

Occurrence and distribution of sarcoptic mange in wild Neotropical canids.