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The purpose of this study is to characterize the pool of lignin phenols in soils of two contrasting secondary forest ecosystems—boreal and tropical—with different tree species and to assess the rate of biochemical transformation of difficult-to-degrade compounds of lignocelluloses nature in them. A detailed and comparative description of the biochemistry of lignin in soils in experiments on artificial afforestation in Krasnoyarsk krai of Russia (Greyzemic Phaeozems (Albic)) and in the Amazon Region, Brazil (Xanthic Ferralsol) is presented. Determination of lignin in soils involved alkaline oxidation with copper oxide at 170°C under pressure in a nitrogen atmosphere. Lignin phenols (vanillin, syringyl, and cinnamyl) were separated, using gas chromatography. It has been shown that lignin mineralization is rapid in soils of both boreal and tropical secondary forests contrary to soils of natural zonal ecosystems. A significant enrichment of lignin with metabolic carbon is a characteristic feature of this process. Low content, high oxidation rate, and a high degree of transformation of lignin are typical for soils of all the studied secondary forests, for tropical ones in particular, which reduces their potential as carbon sink reservoirs versus taiga soils. [ABSTRACT FROM AUTHOR]

Native ecosystems in the lower and middle mountains of the Northwestern Caucasus are mainly represented by secondary arboreous communities with a minor participation of steppe ecosystems. The soil cover of this area comprises a combination of native soil types: brown forest soils or burozems (Cambisols) and soddy-calcareous soils (rendzinas, Rendzic Leptosols). Cambisols predominate under forests of pubescent oak, while rendzinas, which were once formed under Mediterranean steppes, have undergone significant changes and are now found under oak shrubs, ash communities, and lime groves, as well as under preserved steppe vegetation. Consequently, there is a decrease in soil organic carbon (SOC) content in the soil-successional series: leached rendzinas under herbaceous communities, leached rendzinas under tree communities, and brown forest soils. The functioning of rendzinas under arboreous phytocenoses and their further transformation into brown forest soils reliably reduces the SOC content to the depth of 60 cm. In contrast, the SOC content in rendzinas under herbaceous phytocenoses is higher not only in the humus-accumulative horizon but throughout the entire soil profile. The most significant changes in the composition of humus affect its water-soluble fractions separated by cold and hot extractions. Brown forest soils and rendzinas of arboreous phytocenoses are characterized by a similar accumulation of the easily soluble fraction of water-soluble organic matter (cold extraction) in the surface horizons and its depthwise distribution. Meanwhile, the absolute values of water-soluble organic matter (hot extraction) in the profile of rendzinas under arboreous formations are almost halved as compared to soils under herbaceous phytocenoses. The intensity of humification in rendzinas under forest communities decreases due to the destruction of organic matter, which was once strongly associated with calcium, and undergoes maximum transformation because of the change in the composition of plant litter and microclimate under trees. Soil acidity affects the degree of extraction of water-soluble organic matter: the proportion of the hot fraction of water-soluble organic matter in SOC significantly increases with a decrease in pH of the soil solution. [ABSTRACT FROM AUTHOR]

Deciduous forests in northeastern North America are comprised of a mixture of ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) trees. However, land use legacies and other factors have decreased EM and concomitantly increased AM tree dominance, potentially limiting forest ecosystem functioning. We investigated how scattered EM tree patches and soil inoculum from local EM tree‐dominated forests influence EM fungal colonisation, survival and growth of EM Tsuga canadensis, Pinus strobus and Quercus spp. tree seedlings in AM‐dominated secondary forests.Seedlings were planted next to dominant AM Acer and scattered EM Betula trees across three New York secondary forests. A subset of seedlings also received soil inoculum from local EM‐dominated forests. We monitored the survival and height growth of seedlings for 2 years and then measured seedling shoot biomass, assessed EM colonisation and identified EM fungi from seedling roots.All genera of seedlings planted near EM Betula had higher EM colonisation and fungal richness than those planted near AM Acer trees. Inoculation with EM forest soil increased EM colonisation and fungal richness of seedlings only near AM Acer, showing great effectiveness in areas lacking native EM fungi. Total EM fungal diversity on seedling roots was highest near EM Betula, which included numerous taxa usually associated with mature trees. In contrast, EM fungal communities near AM Acer were sparse and mostly dominated by relatively few taxa of spore‐bank fungi. Although seedling survival did not differ between treatments, soil inoculation and proximity to EM Betula increased second‐year height growth of Pinus and Tsuga while soil inoculation alone significantly enhanced shoot mass of Quercus seedlings.Synthesis. Agricultural land use legacies have resulted in expansive secondary forests dominated by AM trees. In these forests, establishment of EM tree seedlings outside existing EM tree patches may be hindered by a lack of EM fungi, but local soil inoculum from EM tree‐dominated forests can reintroduce native EM fungi into secondary forests lacking established EM trees. [ABSTRACT FROM AUTHOR]

Macadamia nuts, scientifically designated as Macadamia integrifolia, are a highly valuable crop that originated in Australia. This study provides a comprehensive examination of the symbiotic relationships between various macadamia root systems and arbuscular mycorrhizal fungi (AMF). The four principal macadamia- producing regions in Yunnan Province were selected for investigation on the basis of meticulous criteria. To determine the AMF infection rate, the roots were stained. Furthermore, high-throughput sequencing was employed to conduct a comprehensive analysis of the fungal diversity in the rhizosphere soil. The findings were definitive, indicating that both normal and cluster roots are capable of establishing a symbiotic relationship with AMF. Secondary forests exhibited significantly elevated fungal diversity relative to normal roots, while cluster roots demonstrated the lowest diversity and notable regional variation, indicating that the environment exerts a considerable influence on inter-root fungi and AMF. The analysis of the fungal community composition revealed that the predominant groups were Ascomycetes and Basidiomycetes. The FUNGuild function prediction clearly indicated distinct differences in the fungal functions of secondary forests, cluster roots, and normal roots. This study provides a scientific foundation for the sustainable development of macadamia nuts and significantly contributes to a deeper comprehension of the intricate interactions between macadamia and AMF, thereby fostering the long-term stable and healthy growth of the macadamia nut industry. [ABSTRACT FROM AUTHOR]

Bringing together and synthesizing data from several primary studies and scales represents a powerful method for identifying patterns and gaps within forest restoration science. In this study, we employ a pioneer quantitative database‐driven review combined with spatial analysis to delineate research trends across biodiversity studies within the Brazilian Atlantic Forest (BAF). We gathered a total of 90 primary studies that met our inclusion criteria, collectively providing 822 observations (comparisons between restoration sites and reference forests) spanning restoration areas with ages ranging from 1 to 90 years old. Vascular plants and invertebrates dominated in terms of data availability, whereas soil microorganisms were the subject of limited inquiry. There is an evident disparity in the number of evidences for different forest types across regions, with mixed forest being underrepresented in relation to seasonal forest and dense forest (rainforest). On the contrary, we observed an even distribution of biodiversity outcomes across the age categories we defined for reference forests (i.e. secondary forest, secondary advanced, and old‐growth forest). Geospatial analysis revealed a concentration of research efforts within the southeastern region of the BAF. However, a significant research deficit remains for the northeast and south regions, crucial for comprehending biodiversity responses to restoration in environmental extremes. By integrating both qualitative and quantitative approaches, this framework review provides a roadmap for deepening our understanding of biodiversity responses to restoration in the BAF. Ultimately, it serves as a bridge between quantitative findings and nuanced contextual insights, guiding future research and similar studies across diverse ecosystems worldwide. [ABSTRACT FROM AUTHOR]

This study aims to assess the woody species carbon stock in the Munessa dry Afromontane forest and its variations within plant community types, as well as altitudinal, slope, and aspect gradients. A systematic sampling technique was used to acquire vegetation data. At a 100-m altitudinal drop, five transect lines were established. Ten quadrats were laid on each transect line (total 50 quadrants) at 200-m distance intervals. The woody carbon was estimated using an appropriate allometric equation formulated for tropical forests. The data was analyzed using one-way ANOVA in R software. The results show that the total woody carbon stock of the Munessa forest is 210.43 t/ha. The analysis of variance revealed that woody carbon stock varied significantly along altitude, slope, and aspect gradients, whereas community types had no significant effect. Middle elevations (2367–2533 m above sea level (m.a.s.l.)), lower slopes (0–13%), and west-facing aspects had the highest mean carbon stock. The Podocarpus falcatus–Croton macrostachyus community type also contributed a higher woody carbon stock since larger tree size classes and older trees are dominant. Overall, the carbon sequestration potential of woody species in the studied forest is strongly associated with environmental variables. Furthermore, the uneven distribution of species with larger diameter at breast height (DBH) in the studied forest might be linked to anthropogenic factors, as the current forest growth indicates characteristics of a secondary forest. Therefore, the present study suggests developing and implementing a sustainable forest management strategy particularly prioritizing middle elevation, lower slope, and west aspects of the forest to maximize the forest's carbon sequestration capacity. [ABSTRACT FROM AUTHOR]

Reproductive barriers between sister species of the mushroom-forming fungi tend to be stronger in sympatry, leading to speculation on whether they are being reinforced by selection against hybrids. We have used population genomic analyses together with in vitro crosses of a global sample of the wood decay fungus Trichaptum abietinum to investigate reproductive barriers within this species complex and the processes that have shaped them. Our phylogeographic analyses show that T. abietinum is delimited into six major genetic groups: one in Asia, two in Europe, and three in North America. The groups present in Europe are interfertile and admixed, whereas our crosses show that the North American groups are reproductively isolated. In Asia, a more complex pattern appears, with partial intersterility between subgroups that likely originated independently and more recently than the reproductive barriers in North America. We found pre-mating barriers in T. abietinum to be moderately correlated with genomic divergence, whereas mean growth reduction of the mated hybrids showed a strong correlation with increasing genomic divergence. Genome-wide association analyses identified candidate genes with programmed cell death annotations, which are known to be involved in intersterility in distantly related fungi, although their link here remains unproven. Our demographic modeling and phylogenetic network analyses fit a scenario where reproductive barriers in Trichaptum abietinum could have been reinforced upon secondary contact between groups that diverged in allopatry during the Pleistocene glacial cycles. Our combination of experimental and genomic approaches demonstrates how T. abietinum is a tractable system for studying speciation mechanisms. • Multiple reproductive barriers between genetic groups in Trichaptum abietinum • Decrease of hybrid growth ability correlates strongly with genomic divergence • Signal of secondary contact between groups supports reinforcement selection • Controlled cell death machinery could play a role in the reproductive barriers Lu et al. found that the forest fungus Trichaptum abietinum contains multiple genetic groups with strong pre-mating barriers in sympatry. Experiments on hybrids show reduced growth with increasing genomic divergence, indicating maladaptive hybridization, which together with the signal of geneflow between groups supports reinforcement. [ABSTRACT FROM AUTHOR]

Nest predation is typically the main cause of nest failure in forest understory birds; thus, identification of primary nest predators is key to understanding nest predation patterns. Furthermore, the responses of predators are likely affected by vegetation structure, but predator responses to micro-scale habitat characteristics are largely unknown, especially in tropical forests. We used a long-term study with one of the largest datasets of its kind to investigate the extent to which micro-habitat structure (5-m radius surrounding a nest) can predict the likelihood of predation and by which predator. In a secondary evergreen forest in northeastern Thailand, 2013–2021, we found 1,016 active nests of 13 species and 24-hour video-monitored 500 of them. We recorded 336 predation events from 16 nest predator species. From this and previous studies at our site, we identified the top 4 predator species/species groups accounting for ~83% of predation events: Macaca leonina (northern pig-tailed macaque, 36% of predation events), cat snakes (Boiga cyanea [green cat snake] and B. siamensis [gray cat snake]; 20%), Lycodon cf. davisonii (Blandford's bridle snake, 18%), and accipiters (Accipiter trivirgatus [Crested Goshawk] and A. badius [Shikra]; 9%). These 4 predator species differed in their responses to vegetation structure likely reflecting differences in foraging behaviors. Macaque and accipiters, both diurnal and visually oriented, tended to depredate more visible/open nests, but macaque depredated nests surrounded by more trees and short woody stems (<3 m tall) compared to raptors. For snakes, both nocturnal, cat snakes depredated nests with higher numbers of both short woody stems and woody climbers, whereas bridle snake depredated nests with more trees and fewer climbers. As noted previously, nest predator identity is critical to understanding habitat-predation patterns. Our data suggest that nest site vegetation characteristics influence the likelihood of a given species of predator locating a nest and that even small changes in vegetation structure could significantly alter predation patterns. [ABSTRACT FROM AUTHOR]

Quercus chungii, a rare and endangered endemic tree species, is found exclusively in subtropical regions of China. Understanding the population structure and temporal dynamics of Q. chungii is pivotal for effective conservation and restoration of its populations and associated ecosystems. However, large knowledge gaps remain about its population structure and temporal change and its key demographic rates across size classes. In this study, we investigated the population structures of Q. chungii in 2013 and 2023 in a nature reserve specifically established to better conserve this species and its associated ecosystems. We found that Q. chungii increased in its overall abundance and tree size in the past decade, suggesting active regeneration and a rapid growth rate for this species and the effectiveness of past conservation efforts. The age structure in 2023 showed a pyramid shape, with a sharp decline in the numbers of individuals from germinated seeds to seedlings and from seedlings to saplings. These led to the low numbers of seedlings and saplings and high age‐specific death probabilities at the early developmental stages. These results indicated potential risks of future population decline. These risks may have already manifested over the past decade, as a high mortality rate during the seedling‐to‐sapling transition could be one of the primary reasons contributing to the decreased proportion of saplings in 2023 compared to 2013. We propose that future studies may benefit from in‐depth studies on the regeneration processes of Q. chungii by considering seed predation and germination under changing climate. This study improves the prediction of population development of Q. chungii, thereby offering theoretical guidance essential for its conservation. [ABSTRACT FROM AUTHOR]

Following old‐growth forest loss and subsequent land abandonment, secondary forest grows throughout the Amazon biome. For Amazonas, agricultural colonization was unsuccessful in many regions, leading to the regeneration of secondary forest and carbon storage under favorable climate conditions. Herein, the extent of regeneration in Amazonas and its timescale are investigated, including a granular analysis of its 62 municipalities, based on the MapBiomas dataset from 1985 to 2021. By 2021, 10,495 km2 of secondary forest had grown, corresponding to 28% of the lost old‐growth forest. After normalization for algorithmic differences, this estimate was 17%–38% lower than prior studies for Amazonas that used earlier versions of the MapBiomas dataset, indicating increased accuracy in landcover assignments for more current versions of the dataset. For the northeastern microregion, representing the 15 municipalities of economic and population dominance in Amazonas, the growth of secondary forest varied from 3.0% to 9.8% of the total land area. For the southern microregion, constituting seven municipalities adjacent to large‐scale deforestation of Mato Grosso and Rondônia, regeneration of secondary forest constituted 0.4%–1.2% of the land area. For the remaining interior municipalities, the regeneration was 0.0%–1.9%. Among the municipalities, the median regeneration interval, corresponding to the duration between the loss of old‐growth forest and the appearance of secondary forest, ranged from 2 to 7 years. The median regeneration intervals of the interior, northeastern, and southern microregions were 3, 4, and 5 years, respectively. Even as the secular trend of deforestation continues in the Amazon biome and encroaches into the southern border of Amazonas state, the results herein indicate a possible resiliency toward secondary forest for undisturbed land on a timescale of several years, at least for mixed pasture‐forest landscapes of kilometer‐scale heterogeneity and assuming that a favorable climate persists for regeneration even as global change occurs. [ABSTRACT FROM AUTHOR]

Vertical stratification is a property of forest habitats related to the differential distribution of organisms according to the variation in the conditions, from the understory to the canopy. Here, we aimed to test whether butterfly assemblages from highly disturbed forests maintain the pattern of vertical stratification. We hypothesized that degraded forests would not exhibit vertical stratification due to the low variation in the microhabitat conditions along the vertical gradient, resulting from the canopy openness. To test this, we sampled fruit-feeding butterflies with bait traps, alternately disposed between the understory and canopy of three secondary forest fragments in a very fragmented Atlantic Forest landscape, for one year. We found that the vertical strata differed in terms of species composition, with a high contribution by the nestedness component on the beta diversity spatial variation. The understory assemblages had a higher abundance and were more diverse than the upper stratum. We demonstrated that vertical stratification is maintained even in disturbed forests; however, this does not necessarily provide support for a good quality and functioning ecosystem in these habitats. The butterfly assemblages recorded here are a subset of the species pool that inhabits conserved remnants. Thus, even being represented by species commonly found in disturbed habitats, the dynamic of vertical stratification of assemblages remains. [ABSTRACT FROM AUTHOR]

Swing yarders in running skyline configuration using either grapples or chokers represent the most common configuration for cable yarding in coastal British Columbia. In this context, whole-tree logging and short work cycles lead to heavy and repeated loads applied to the trees and stumps when used as anchors for the rigging cables. Moreover, increased harvesting of second-growth forest stands leads to the unavailability of large and safe trees, thus introducing new challenges to identify suitable anchors and potentially increases safety risks of cable yarding operations. The present study aimed to collect evidence of the mechanical response provided by anchors for typical cable yarders used in second-growth harvesting in coastal British Columbia, and test the suitability of innovative techniques for the stability assessment based on the relationship between the anchor root-plate rotations and the related applied tensile forces. A conspicuous dataset could be derived from all the surveys, storing anchor rotations from a total of 1522 work cycles of which 1224 work cycles included also tensions measurements. The methodological approach was proven effective for monitoring different rigging configurations giving proof that repeated loading affects the stability of a tree/stump which can rapidly change over few hours of active yarding operations. Acquired data proved also that comparing theoretical failure limits with anchor rotations could be a valid approach however a considerable amount of species-specific data from tree pulling tests is required. [ABSTRACT FROM AUTHOR]

Billions of genomic sequences and records of species occurrence are available in public repositories (e.g. National Center for Biotechnology Information, NCBI and the Global Biodiversity Information Facility, GBIF). By implementing analytical tools from different scientific disciplines, data mining these databases can aid in the global surveillance of zoonotic pathogens that circulate among wildlife. We illustrate this by investigating the Hantavirus–rodent system in the Americas, i.e. New World Hantaviruses (NWH). First, we considered the circulation of pathogenic NWH among Cricetidae rodents, by inferring the phylogenetic links among 277 genomic samples of the S segment (N protein) of NWH found in 55 species. Second, we used machine learning to assess the impact of land use on the probability of presence of the rodent species linked with reservoirs of pathogenic Hantaviruses. Our results show that hosts are widely present across the Americas. Some hosts are present in the primary forest and agricultural land, but not in the secondary forest, whereas other hosts are present in secondary forest and agricultural land. The diversity of host species allows Hantavirus to circulate in a wide spectrum of habitats, in particular rural rather than urban. We highlight that public repositories of genomic data and species occurrence are very useful resources for monitoring potential enzootic transmission and spillover of zoonotic viruses in relation with the changes that humans produce in the biosphere. [ABSTRACT FROM AUTHOR]

The widely observed negative scaling relationship between organism size and abundance is predicted to have a universal −0.75 scaling exponent across all life forms. However, factors influencing frequently observed deviations from this exponent, such as ecosystem succession and organism traits, remain poorly understood.We explore the dependence of size–density scaling on ecosystem succession and organism traits by analysing size–density relationships in trees and soil invertebrates across 183 temperate forest plots comprising urban secondary forests, urban old‐growth forests and non‐urban natural forests.Exponents of scaling relationships in urban tree and invertebrate communities progressively steepened with increasing restored (planted) forest stand age as small organisms increased in abundance. In contrast, non‐urban tree scaling relationships flattened during succession with exponents veering away from −0.75, whereas urban tree and invertebrate communities converged towards this prediction in later successional stages.Our results shed light on how the body size structure of tree and soil invertebrate communities spanning multiple trophic levels shift over successional time as the relative abundances of large versus small‐bodied organisms increase. This study emphasises the fundamental influence of organismal traits and ecosystem succession on scaling relationships of organism body size and abundance. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

[Objective Aggregated stability is an important indicator for assessing changes in soil quality after vegetation restoration in degraded ecosystem. The aims of this study are to investigate the difference of soil aggregate stability and its change mechanism of main forest types in central Yunnan, and to provide scientific support for tree species selection and forest resource scientific management in the process of vegetation restoration and transformation in the future. Methods] Six primary forest types, including Pinus yunnanensis forest (PY). Pinus armandii forest (PA). Acacia dealbata forest (AD) and Alnus cremastogyne forest (ACF). Theropencedrymion forest (TF), and Secondary evergreen broad-leaved forest (SF). were selected for the study. Dry slope land (DSL) was used as a control. Soil samples were collected from depths of 0-20 cm, 20-40 cm, and 40-60 cm. Dry sieving and wet sieving methods were employed to classify aggregates into four size classes: 5 mm.5~2mm.2~0.25 mm and 0.25 mm. Four stability indices, including WR. mean weight diameter (MWD), geometric mean diameter (GMD) and structural failure rate (PAD), were calculated to investigate soil aggregate stability. [Results] (1) Among the six forest types, aggregates with a particle size range of 0.25-2 mm predominated in the 0-60 cm soil layers, while DSL shifted from 0.25-2 mm to 0.25 mm with increasing soil depth. (2) In the 0-60 cm soil layer WR MWD. GMD. and PAD values in DSL. were 55.40%, 1.16 mm, 0.52 mm, and 40.47%, respectively. The six forest types exhibited aggregate stability ranging from 71.61% to 78.20% for WR 1.97 mm to 2.61 mm for MWD, 0.93 mm to 1.27 mm for GMD. and 12.59% to 20.47% for PAD. Overall. DSL exhibited the poorest aggregate stability. followed by SF and TF, while PY. ACF, AD, and PA showed relatively lower stability. (3) At the macro scale, soil aggregate stability in the study area was significantly influenced by forest type, soil depth and their interaction (p<0.001). At the micro scale, it was mainly affected by soil bulk density, non-capillary porosity total potassium, soil organic matter sand content and clay content (p<0.05). Soil physicochemical properties, nutrients, and texture explained 90.5% of aggregate stability, with the greatest contribution coming from the interaction of physicochemical properties and nutrients, accounting for 61.3%. Soil texture often interacted with other factors to influence aggregate stability, with an independent explanatory power of only 5.1%. [Conclusion] In central Yunnan, the stability of soil aggregates can be significantly improved by returning farmland to forest. Future ecological restoration should focus on creating Pinus yunnanensis and Alnus cremastogyne forest, while avoiding high-intensity human activities. improving soil physical and chemical properties and increasing soil nutrient accumulation, and promoting the evolution of artificial pure forest into theropencedrymion forest and secondary forest. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to reveal the characteristics of preferential flow and the influence of root system on it in southwest karst region, to clarify the influence of root system on the degree of preferential flow of different vegetation types, and to provide a basis for local vegetation restoration and water conservation. [Methods] Three typical forest types in Yunnan karst region were selected as the research objects. Field dye tracing and statistical analysis were combined to obtain the vertical and horizontal profile morphological characteristics of preferential flow and the dye area ratio. Combined with four root system parameters including root length density, root surface area density, root volume density, and root biomass density, the degree of preferential flow caused by root systems in different forest types was calculated using one-way analysis of variance, in order to determine the influence of root systems on preferential flow. [Results] (1) The overall characteristics of the root systems in the three typical forest types were natural secondary forest natural mixed forest > artificial pure forest. (2) The maximum dye depth in different forest types was 20-30 cm, showing a decreasing trend with increasing depth. Both the vertical and horizontal profiles reflected the lateral seepage of soil moisture. (3) The matrix flow appeared in the surface layer of soil, and the remaining dye profiles showed a downward flow pattern resembling fingers or funnels as the soil layer deepened, indicating obvious root paths. The preferential flow in the mixed forest mainly occurred through vertical infiltration, while the horizontal flow development degree was higher in pure forests. Among them, the pure natural forest had the highest preferential flow ratio and the smallest length index, indicating that a complex root structure could effectively enhance the depth of water movement in the soil. (4) The results of one-way analysis of variance between the root system parameters of the three typical forest types and the corresponding dye area all showed R²>0.8 at the level of p<0.05, indicating that the root system parameters were closely related to the development of preferential flow and had a promoting effect. Conclusion] Root characteristics of the three typical forest stands are closely related to the development of the preferential flow and all of them promote the development of the preferential flow, but the correlation between the root indexes and the development of the preferential flow vary among different forest types. Root system indicators of natural secondary forests show negative correlations; root length density and root surface area density of planted pure forests show positive correlations, and root volume density and root biomass density show correlations; root system indicators of natural mixed forests show positive correlations. [ABSTRACT FROM AUTHOR]

Soil water is a crucial factor for the growth of vegetation and sustainable development in water‐limited areas. After large‐scale vegetation restoration on the Chinese Loess Plateau, understanding the relationship between vegetation and deep soil moisture has become a crucial focus in current research. In this study, artificial forest (Pinus tabulaeformis [PT], Robinia pseudoacacia [RP] and Platycladus orientalis [PO]), apple orchard (AO), secondary forest (SF) and farmland (FL) were selected as the research objects, and grassland (GL) as the control, using soil‐drilling techniques. We systematically monitored the soil water content of 0–10 m soil layer over two hydrological years, and explored the effects of different vegetation types on soil water deficiency. The results showed that: (1) The deep soil water various significantly among different vegetation types. Compared with GL, the soil water content in all forest land was generally lower, and this difference became more pronounced in deeper soil layer (>7 m), which indicating the depth of the influence of vegetation on soil water has reached 10 m. (2) The mean soil water deficit size (SWDS) values of PT (0.14), RP (0.17), PO (0.07), AO (0.15), SF (0.10) and FL (0.27) in 0–1 m were all positive, indicating that surface soil water had accumulated during more than half of the sampling periods. In the 2–10 m soil layer, mean SWDS was negative in all vegetation types except in FL, leading to soil desiccation. SWDS was found to fluctuate with soil depth. (3) SWDS was affected by a combination of soil properties and vegetation growth. Our results indicate that the current afforestation model could lead to the deficiency of deep soil water. Therefore, it is imperative to make reasonable vegetation structure according to the available local soil and water resources in future vegetation allocation and management. [ABSTRACT FROM AUTHOR]

As a habitat option for the rapidly declining old-growth forests, secondary forest patches will serve as refugia for forest species in the tropics. The present study was carried out to determine the conservational significance of the Upper Hanthana secondary forest patch in Sri Lanka, based on its avifaunal diversity and endemism. The field survey was conducted from March-November 2019. Data were collected using line transects along with point counts. Peak observation hours were during 0700-1000 h and 1500-1800 h in the sites selected by systematic random sampling. Results were compared with those of a nearby village area. According to statistical analysis, the Upper Hanthana secondary forest patch harbours a comparatively higher avifaunal diversity with 87 bird species and remarkable endemism of 17 endemic bird species out of total 34 endemic bird species in Sri Lanka. The present study highlights the significance of the Upper Hanthana forest patch for biodiversity conservation. Further studies are required to evaluate the total biodiversity of this secondary forest patch and assess better conservational measures. [ABSTRACT FROM AUTHOR]

Environmental legislation requires well‐defined concepts, criteria, and indicators to support its effective implementation and provide legal security to the diverse stakeholders involved. The Native Vegetation Protection Law (NVPL) establishes the obligation to restore native vegetation in protected areas within rural properties. This federal law is regulated and implemented by each state through its own Environmental Compliance Program (Programa de Regularização Ambiental [PRA], in Portuguese). Landowners must register their land, indicate whether native vegetation needs to be restored (i.e. if there is an environmental debt), and submit a restoration plan to the state government for analysis, validation, and approval. Due to the high cost of forest restoration, natural regeneration has most likely become a viable strategy for Amazonian landowners to meet their environmental debts. However, according to disturbance intensity, frequency, and duration, natural regeneration will not always succeed. In this context, we analyzed the PRAs of the seven main Amazonian states to assess the status of their implementation, identify how natural regeneration is defined and approached in the law, and evaluate whether improvements in the law are needed to ensure effective restoration to accomplish the NVPL. [ABSTRACT FROM AUTHOR]

Introduction: Understory removal is frequently used to relieve the renewal pressure on trees and promote the growth capability of trees for maintaining community stability, while the lack of previous study on temperate forests limits our assessment of the effectiveness of this essential management measurement. Methods: In this study, we calculated the niche characteristics and interspecific association of main understory species and community stability in temperate forests [original broad-leaved Korean pine forest (BKF), Betula platyphylla secondary forest (BF), and Larix gmelinii plantation (LF)] after understory removal for characterizing the resource utilization capacity of the regeneration trees. Results: During the restoration stage, the niche breadth of understory plants with similar habits varied across stands and layers; regeneration tree species with heliophile and semishade occupied a larger niche in BKF and LF, while it was the opposite in LF. Niche overlap among heliophile regeneration trees increased in both BKF and BF, but not in LF. The interspecific association among main species revealed that the distribution of each species was independent and the interspecific association was loose and it varied in different forests and different light-demanding species with regeneration trees. The stability of shrub communities in BF and LF improved whereas that of BKF declined, while that of the herb communities of corresponding forests showed the opposite state. Discussion: Our study demonstrated that the effectiveness of understory removal depends on species' ecological habits, which enhances the renewal and resource utilization capacity of regeneration tree species in temperate forests and shrub community stability in BF and LF. [ABSTRACT FROM AUTHOR]

Simple Summary: A large portion of tropical forests around the world have been impacted by human disturbances such as clearcutting or selective logging. Impacts from these disturbances may remain long after the trees grow back, as other aspects of forest structure may have changed. Forests that are recovering from disturbances still play an important role for wildlife, though their conservation value compared to undisturbed forests is not well understood. To examine how different types of human disturbance impact tropical forest birds, we surveyed and compared bird communities in three different forest habitats: undisturbed primary forest, selectively logged forest (low disturbance), and forest replanted on abandoned agricultural fields (high disturbance). Our surveys occurred 19 years after any logging or agriculture, allowing our forest sites time to regrow. We found that while bird communities at low-disturbance sites were similar to undisturbed sites, high-disturbance sites had fewer bird species, with ant-following birds being particularly underrepresented. We related these results to vegetation structure measurements, which suggested that reducing tree density and vegetation ground cover in high-disturbance forests may improve these areas as tropical forest bird habitats. As tropical forests are frequently impacted by human disturbance, forests in various stages of disturbance recovery are increasingly important for maintaining biodiversity. However, much remains unclear regarding the impacts of prior disturbance intensity on wildlife in regenerating forests. Here, we used mist net capture data to compare bird communities in three tropical forest habitats representing various disturbance intensities: undisturbed primary forest, selectively logged forest (low disturbance), and secondary forest regenerating on abandoned agricultural fields (high disturbance). We found that after a 19-year recovery period, low-disturbance sites contained similar bird communities to undisturbed sites. High-disturbance sites, however, had lower species richness and distinct bird communities, with fewer insectivores and more nectarivores than other sites. Structural equation models revealed that the impacts of disturbance intensity on bird communities were partially explained by changes in vegetation structure: ant-following insectivore abundance declined with disturbance intensity as ground cover vegetation increased, and nectarivore abundance increased with disturbance intensity as tree density decreased. Our results suggest that selectively logged forests can regain pre-disturbance bird diversity and vegetation structure within two decades, provided that they are protected from further disturbance and located near source species pools. Increasing tree density and decreasing ground-level vegetation in secondary forests may improve these areas as habitats for forest-interior birds. [ABSTRACT FROM AUTHOR]

Land management practices that overlook soil limitations and potential have led to varying degrees of degradation. This study evaluates the carbon content in chemical and oxidisable soil fractions across different pasture recovery periods, comparing them to secondary forests. The management practices assessed include the following: secondary forest (SF), perennial pasture (PP), perennial pasture recovered five years ago (P5), and perennial pasture recovered eight years ago (P8), all on Plinthosols. We analysed carbon levels in oxidisable fractions and humic substances at depths of 0–0.10 m, 0.10–0.20 m, 0.20–0.30 m, and 0.30–0.40 m. The SF and P8 areas showed the highest organic matter content within the humic fractions, compared to the PP and P5 areas. Additionally, the P8 area demonstrated an increase in the labile and moderately recalcitrant fractions of organic matter, standing out among the different fractions evaluated. The multivariate principal component analysis indicated that P8 has the greatest impact on soil quality, followed by FS, P5, and PP. The pasture recovery over the past eight years has significantly improved soil carbon accumulation, highlighting the benefits of land restoration. [ABSTRACT FROM AUTHOR]

Simple Summary: The distribution and biology of Protaetia fieberi (Kraatz, 1880) (Scarabaeidae: Cetoniinae) in European Russia were investigated. This species is reliably known from 26 regions. The limiting factors that prevent the spread to the north, south, and southeast of European Russia have been identified. Within its range, the species inhabits deciduous and mixed forests of various types. The species also inhabits anthropogenic forest ecosystems. In forests, the species adheres to the upper tiers of the forest. Adults feed on the leaking sap on trunks and less often on flowering plants. Seasonal dynamics is characterized by highs from the third decade of June to the second decade of July. The status of the species is being discussed. Studies on saproxylic species of Coleoptera have garnered significant attention due to the rarity of some of them. To investigate the distribution and biology of Protaetia fieberi (Kraatz, 1880) (Scarabaeidae: Cetoniinae) in European Russia, we analyzed data from 16 regions collected between 2018 and 2024. This species has been reliably recorded in 26 regions. We describe the species' distribution area boundaries and discuss limiting factors that inhibit its spread to the north, south, and southeast of European Russia. The primary limiting factor is the lack of suitable biotopes. Within its distribution, Protaetia fieberi prefers deciduous and mixed forests of various types. These habitats include both old-growth forest ecosystems and secondary forests that have regenerated following logging. The species also inhabits man-made forest ecosystems, such as field protection forest belts, old parks, and gardens. In forest ecosystems, Protaetia fieberi tends to occupy the upper levels and is rarely found on the ground layer. Conversely, in open areas such as glades, the species is more commonly found at ground level. This distribution pattern is linked to the adults' feeding preferences, which include consuming sap on tree trunks in forests and feeding on flowering plants in open ecosystems. The seasonal activity of Protaetia fieberi peaks from the third decade of June to the second decade of July. It is hypothesized that the perceived rarity of Protaetia fieberi in research samples is due to the specific baiting methods used, with beer traps being the most effective. The status of the species is re-evaluated in light of new data, suggesting that Protaetia fieberi is common rather than rare in European Russia. [ABSTRACT FROM AUTHOR]

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

Monitoring of stream water quality is a key element of water resource management worldwide, but methods that are commonly used in temperate habitats may not be appropriate in humid tropical systems. We assessed the influence of four land uses on microbial water quality in 21 streams in the Panama Canal Watershed over a one-year period, using a common culture-based fecal indicator test and 16S rDNA metabarcoding. Each stream was located within one of four land uses: mature forest, secondary forest, silvopasture, and traditional cattle pasture. Culturing detected total coliforms and Escherichia coli across all sites but found no significant differences in concentrations between land uses. However, 16S rDNA metabarcoding revealed variability in the abundance of coliforms across land uses and several genera that can cause false positives in culture-based tests. Our results indicate that culture-based fecal indicator bacteria tests targeting coliforms may be poor indicators of fecal contamination in Neotropical oligotrophic streams and suggest that tests targeting members of the Bacteroidales would provide a more reliable indication of fecal contamination. [ABSTRACT FROM AUTHOR]

The interspecific relationship between functional traits and tree seedling performance can be inconsistent, potentially due to site-to-site or microsite variation in environmental conditions. Studies of seedling traits and performance often focus on above-ground traits, despite the importance of below-ground resource acquisition and biomass allocation to above versus below-ground functions. Here we investigate how varying environmental conditions across sites induce intraspecific variation in organ-level (above-ground, below-ground) and biomass allocation traits, affecting interspecific relationships between these traits and seedling performance. We analyzed trait expression for 12 organ-level and three allocation traits and their relationships with height growth (1716 seedlings) and mortality (15,862 seedlings) for 26 tree species across three sites along a forest successional gradient in Costa Rica. We found significant intraspecific differences across sites in all allocation traits, but only in three of seven above-ground and three of five below-ground organ-level traits. Allocation traits were better predictors of seedling performance than organ-level traits. Relationships between allocation traits and both growth and mortality varied among all sites, but for organ-level traits, only relationships with growth varied among sites. These results underscore that biomass allocation plays a key role in the earliest life stages of trees and that site-specific conditions can influence how functional traits mediate seedling establishment during succession. [ABSTRACT FROM AUTHOR]

Currently, there is a marked increase in the importance of the environmental and cultural ecosystem services of the forest. Among the social benefits, protection of human health and improvement of human well-being come to the fore. Forests, both reserve and commercial, benefit human health. However, people often have negative attitudes toward forest management activities, especially near urban areas, and prefer forest management that results in a forest that is close to natural. Second-growth forest and clear-cutting are the most visible manifestations of ongoing forest management in forests. The purpose of this study was to compare the benefits derived from exposure to second-growth forest, clear-cutting and mature forest stands. Fifty-five students of the Warsaw University of Life Sciences-SGGW (WULS-SGGW) participated in the study. The study was conducted in October 2023 in a forest within the city of Otwock, within the range of the Warsaw metropolitan area. Participants were exposed for 15 min to selected plots: second- growth forest, clear-cutting area and mature forest stand. Before the experiment (PRE-Test control trial) and after each of the exposures four psychological questionnaires were administered: the Positive and Negative Affect Schedule (PANAS), the Restorative Outcome Scale (ROS), the Subjective Vitality Scale (SVS) and Profile of Mood States (POMS). The results indicate that not all analyzed features of the forest landscape have a regenerative effect on people. Exposure to a commercial forest, only in the case of a mature stand, yielded the most benefits in terms of mood improvement. In contrast, exposure to clear-cutting area resulted in a decrease in positive feelings and an increase in negative feelings, leading to a complete disturbance of mood, an increase in tension, depression and a decrease in feelings of vigor. Clear-cutting area has significantly worse restorative properties compared to mature forest stands and second-growth forest. This observation is relevant to forest management within city limits and in the suburban zone of large cities. Not only is clear-cutting area not accepted by people visiting forests for recreational purposes, but it leads to a detraction from the health benefits provided by forests. [ABSTRACT FROM AUTHOR]

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Nitrogen (N) is a limiting component in the function and stability of karst ecosystems. Different amounts of N additions have been shown to influence the metabolic processes of microbial communities and vegetation. Thus, this study aimed to evaluate how soil metabolism responds to N addition amounts in grassland (GL), shrubland (SL), secondary forest (SF) and primary forest (PF) in karst areas of southern China. Three N addition treatments were applied: no N addition (CN, no N fertilizer), low N addition (LN, 50 kg N ha-1 year-1), and high N addition (HN, 100 kg N ha-1 year-1). The results revealed that N addition has a substantial impact on soil metabolite composition and abundance in GL, SL, SF, and PF. Additionally, N addition had distinct impacts on soil metabolism in different vegetation types. N addition significantly reduced several fatty acids in GL, including 9-oxooctadecanoic acid and cis-9,10-epoxystearic acid. N addition to SL resulted in an increase of organoheterocyclic compounds, including clothianidin and gabapentin related compound A. In SF, low N considerably reduced metabolite abundance, while high N dramatically increased metabolite abundance. N addition in PF mainly resulted in the upregulation of soil metabolites. These results provide valuable information for understanding the biochemical impact of N addition in various karst vegetation types. [ABSTRACT FROM AUTHOR]

Agricultural expansion is one of the main causes of deforestation of tropical montane forests in the central Andes of Peru. The hydrological impacts of converting forests to cropland are well known; however, an issue that is not entirely clear is related to the hydrological effects that can result from the conversion of montane forests to agroforestry systems and the recovery of the hydrological functions of montane forests after a disturbance. In this study, we compare the hydrological processes of different land covers previously modified by agricultural expansion, in order to determine the impact of the conversion of tropical montane forest to agricultural land on the ecosystem service of water provision and regulation. To achieve this, we establish study plots in four land cover types located in the central Andes of Peru (mature montane forest (BMC), natural regenerating secondary forest (BMR), coffee agroforestry systems (AF), and cropland (C)), for the purpose of measuring the vegetation structure and soil properties in them, and subsequently carry out a soil water balance in each plot to calculate the actual evapotranspiration, surface runoff, and groundwater recharge. The results revealed the following percentages (based on precipitation) for the hydrological components in the four land cover types: annual actual evapotranspiration—BMR (41.2%), AF (40.4%), BMC (40.0%), and C (38.0%); annual surface runoff—C (16.1%), BMC (8.3%), BMR (5.2%), and AF (4.6%); and annual groundwater recharge—AF (43.0%), BMR (41.6%), C (34.0%), and BMC (31.7%). Furthermore, the study also examined the relationship between vegetation structure and the hydrological components across the four land cover types. The findings indicated that the reduction of thicker and taller trees could increase surface runoff generation, whereas the presence of thinner and shorter trees could facilitate groundwater recharge. These results shed light on the complex interactions between land cover types, vegetation structure, and hydrological processes, emphasizing the importance of considering these factors in water resource management and land use planning. [ABSTRACT FROM AUTHOR]

Ecological restoration and biodiversity are currently hot issues of global environmental concern. However, knowledge about the specific impacts of restoration duration on understory vegetation diversity remains limited. Therefore, this study comprehensive employed a spatial approach to compare the differences in understory plant diversity and species composition among secondary forests with varying ecological restoration ages (0, 10, 30, 60, and 90-year-old stands) in Huangfu Mountain National Forest Park. This methodology allowed us to clarify the key factors affecting the composition of the understory plant community and investigate the regulatory mechanisms influencing changes in understory plant diversity. The results showed that shrub Shannon's index value, shrub evenness, herb Shannon's index value, herb richness, and herb evenness were significantly affected by the years of restoration, with 10 years and 90 years being the highest and 60 years being the lowest. Substrate diversity was the main factor influencing plant diversity in the shrub layer. Overstory richness, soil C/N, soil C, soil N, soil bacterial Observed OTUs, soil bacterial Chao1, soil bacterial Pielou_e, and substrate diversity were the drivers of plant diversity in the herb layer. Overstory evenness had a direct effect (0.256) and an indirect effect (0.284) on herb evenness through light availability and fungal Simpson's index value. Light availability directly negatively affected herb evenness (−0.360). In addition, 52.6% of the factors affecting the herb evenness index were from the arboreal layer evenness, light availability, and fungal Simpson's index value. To sum up, moderate disturbance of the understory environment of natural secondary forests can be carried out after 10 years of restoration, which is more conducive to the increase of understory plant diversity. This comprehensive study provides a theoretical basis for formulating ecological restoration measures for secondary forests, particularly in understanding the optimal timing and nature of disturbance in the restoration process, reassuring the audience about the validity and reliability of the findings. [ABSTRACT FROM AUTHOR]

Enunciating the carbon storage across various types of forests is a precondition for comprehending forest ecosystem carbon cycling. However, previous studies regarding forest carbon storage were primarily conducted in the general temperature zones, with a limited understanding of carbon storage in different forest types within climate transition zones. In this study, we employed biomass models to explore the carbon storage in three types of natural secondary forests (Pinus armandii forest, Quercus aliena forest, and Q. aliena–P. armandii mixed forest) in the transition zone between the northern subtropical and warm temperate regions of China. Furthermore, we used the variance decomposition analysis and random forest model to determine the key factors influencing carbon storage in three types of natural secondary forests. Our results indicated that the carbon storage of wood and soil layers in the Q. aliena–P. armandii mixed forest was significantly higher than that in the P. armandii and Q. aliena forests. Total carbon storage was ranked as follows: Q. aliena–P. armandii mixed forest (266.09 t/ha) > P. armandii forest (222.89 t/ha) > Q. aliena forest (212.46 t/ha). Our results also revealed that carbon storage of the wood layer was jointly regulated by environmental factors, plant physiological characteristics, and soil properties, while soil carbon storage was mainly affected by soil properties. These results highlight the significant advantages of mixed conifer–broadleaf forests in carbon storage, emphasizing the importance of mixed natural secondary forests in carbon cycling and ecosystem services. This study provides scientific evidence for enhancing forest carbon sink functions and developing forest conservation and management policies to combat climate change. [ABSTRACT FROM AUTHOR]

In this study, the near-naturalization process of Pinus tabulaeformis plantations in Baxianshan National Nature Reserve was divided into three stages depending on the proportion of P. tabulaeformis present, resulting in the following categories: the P. tabulaeformis forest stage, the mixed forest stage, and the near-natural forest stage. Natural secondary forests were selected as a control. We assessed alterations in the soil's fungal functional structures from three aspects: functional mode, vegetative mode, and growth mode, and their responses to vegetation and soil factors were also explored. The results showed that ectomycorrhizal, saprophytic, and plant pathogen types were dominant in the functional mode, and plant pathogens were most abundant in the P. tabulaeformis forest stage. Meanwhile, ectomycorrhizal fungi were the least abundant in the near-natural forest stage. In the vegetative mode, saprophytic, pathophysiological, and symbiotic types were dominant, and pathophysiological types were the most abundant in the P. tabulaeformis forest stage. In the growth mode, microfungi dominated, and the abundance of clavarioid decreased with near-naturalization. The degree of variation in functional structure in the three dimensions increased with near-naturalization, but the structure of natural secondary forests converged. The species composition of tree layer obviously affected the abundance and functional structure of fungi in the three modes, among which Quercus mongolia and Carpinus hornbeam were the most significant. The soil's pH and nitrate content significantly affected the structure of the functional mode, and the soil's dry matter content and C/N ratio significantly affected the structure of the vegetative mode. In this study, we explored the interaction between the plant community and soil ecological system during the near-naturalization process of plantations in terms of soil fungi functions, further clarifying the role of soil functions in the succession of plant communities and providing a new perspective on the in-depth exploration of ecosystem interactions during the succession of plantations. [ABSTRACT FROM AUTHOR]

In tropical disturbed forests, it is relatively unknown the extent insect communities are experiencing shifts in species diversity and the consequences for ecosystem functions and services. In southern Mexico, we used the rove beetle community associated to Heliconia wagneriana bracts, as a model system, to investigate differences in community attributes and feeding habits between old-growth and human induced secondary forests. We tested if the beta diversity components of rove beetle communities were influenced by forest type and bract traits. Furthermore, we described the topology of individual-based heliconia-rove beetle ecological networks. Overall, we recorded 26 rove beetle species with significantly greater abundance in secondary forests. High compositional dissimilarity between forest types was observed with saprophagous species being more likely detected in old-growth forests; whereas predatory species in secondary forests. Heliconia-rove beetle networks showed a significant nested pattern with incidence data for old-growth forests and incidence and abundance data for secondary forests. Compared to old-growth forests, the rove beetle community in secondary forests showed strong shifts in species composition, diversity and differences in the detection probability of feeding habits, with consequences for ecosystem functioning. We further discuss these findings according to the forest disturbance and phytotelm systems. Implications for insect conservation: Individuals of H. wagneriana represent biodiversity reservoirs for invertebrates, especially in human-modified landscapes. [ABSTRACT FROM AUTHOR]

As tropical forests are frequently impacted by human disturbance, forests in various stages of disturbance recovery are increasingly important for maintaining biodiversity. However, much remains unclear regarding the impacts of prior disturbance intensity on wildlife in regenerating forests. Here, we used mist net capture data to compare bird communities in three tropical forest habitats representing various disturbance intensities: undisturbed primary forest, selectively logged forest (low disturbance), and secondary forest regenerating on abandoned agricultural fields (high disturbance). We found that after a 19-year recovery period, low-disturbance sites contained similar bird communities to undisturbed sites. High-disturbance sites, however, had lower species richness and distinct bird communities, with fewer insectivores and more nectarivores than other sites. Structural equation models revealed that the impacts of disturbance intensity on bird communities were partially explained by changes in vegetation structure: ant-following insectivore abundance declined with disturbance intensity as ground cover vegetation increased, and nectarivore abundance increased with disturbance intensity as tree density decreased. Our results suggest that selectively logged forests can regain pre-disturbance bird diversity and vegetation structure within two decades, provided that they are protected from further disturbance and located near source species pools. Increasing tree density and decreasing ground-level vegetation in secondary forests may improve these areas as habitats for forest-interior birds.

Brazil, a crucial player in global climate change mitigation, faces challenges in reducing its carbon emissions, of which nearly half are from land use changes. Despite potential reductions that can be achieved through halting deforestation and fostering forest restoration, setbacks in environmental governance have heightened emissions. This article assesses challenges and proposes solutions for conserving and restoring Brazilian biomes in line with the Sustainable Development Goals (SDGs) and the Paris Agreement by 2030. Notably, net carbon emissions from land-use change and forestry increased twofold from 2017 to 2022 due to deforestation in the Amazon and Cerrado. Native vegetation clearing peaked at 2.8 Mha in 2022, the largest area since 2008. The deficit of native vegetation within Legal Reserves and Permanent Protection Areas must be addressed through restoration. Achieving SDGs by 2030 demands urgent action against illegal deforestation, reinforced legislation for secondary forest protection, large-scale restoration programs, and economic incentives for forest conservation through payment for ecosystem services to rural landowners.

The investigation into the spatial distribution of living woody (LWD) and coarse woody debris (CWD) within forests represents a fundamental methodology for probing the inherent mechanisms governing coexistence and mortality within forest ecosystems. Here, a complete spatial randomness (CSR) null model was employed to scrutinize the spatial pattern, while canonical correspondence analysis (CCA) and the Torus-translation test (TTT) were utilized to elucidate the distribution patterns of LWD and CWD within warm-temperate deciduous broadleaf secondary forests in Dongling Mountains plot, northern China. The results reveal that both LWD and CWD exhibit an aggregated distribution as the predominant pattern in the Dongling Mountains plot, with the proportion and intensity of aggregation diminishing as spatial scale increases. Specifically, the aggregation intensity g0–10 demonstrates a significant negative correlation with abundance and maximum diameter at breast height (DBH). Notably, the g0–10 of LWD manifests a stronger correlation with the maximum DBH, whereas the g0–10 of CWD exhibits a greater association with the mortality rate. CCA outcomes suggest that elevation, convexity, and aspect significantly impact LWD distribution, whereas CWD distribution shows substantial negative correlations with elevation, convexity, slope, and aspect. TTT findings indicate that ecosystems characterized by a substantial presence of LWD also display a notable prevalence of CWD. Additionally, the majority of species exhibit no habitat preference, displaying neutral habitat connections and low ecological niche differentiation within the sampled plot. [ABSTRACT FROM AUTHOR]

Soil hydrology seriously affects the prevention of desertification in karst areas. However, water infiltration in the different soil layers of secondary forests and artificial forests in karst areas remains uncertain. This lack of clarity is also the factor that constrains local vegetation restoration. Therefore, monitoring and simulating the priority transport of soil moisture will help us understand the shallow soil moisture transport patterns after artificial vegetation restoration in the local area, providing a reference for more scientific restoration of the ecological environment and enhancement of carbon storage in karst areas. The integration of soil physical property assessments, computed tomography (CT) scanning, dye tracing studies, and HYDRUS-2D modeling was utilized to evaluate and contrast the attributes of soil macropores and the phenomenon of preferential flow across various forestland categories. This approach allowed for a comprehensive analysis of how the soil structure and water movement are influenced by different forest ecosystems and infiltration head simulations (5 mm, 15 mm, 35 mm, and 55 mm) to elucidate the dynamics of water movement across diverse soil types within karst regions, to identify the causes of water leakage due to preferential flow in secondary forests, and to understand the mechanisms of water conservation and reduction in artificial forests adopting a multifaceted approach. This study demonstrated that (1) the soil hydrological capacity of a plantation forest was 20% higher than a natural forest, which may be promoted by the clay content and distribution. (2) Afforestation-enhanced soils in karst regions demonstrate a significant capacity to mitigate the loss of clay particles during episodes of preferential flow and then improve the soil erosion resistance by about 5 times, which can effectively control desertification in karst area. (3) The uniform distribution of macropores in plantation forest soil was conducive to prevent water leakage more effectively than the secondary forest but was incapable of hindering the occurrence of preferential flow. The secondary forest had a very developed preferential flow phenomenon, and soil clay deposition occurred with an increase in depth. (4) Moreover, the results for preferential flow showed that the matrix flow depth did not increase with the increase in water quantity. Short-term and high-intensity heavy rainfall events facilitated the occurrence of preferential flow. Infiltration along the horizontal and vertical directions occurred simultaneously. These results could facilitate a further understanding of the contribution of the plantation to soil amelioration and the prevention of desertification in karst areas, and provide some suggestions for the sustainable development of forestry in karst areas where plantation restoration is an important ingredient. [ABSTRACT FROM AUTHOR]

Recent field surveys of the flora of Niue have identified three new species records for the island. Erigeron bellioides DC. (Asteraceae) and Psidium cattleyanum Sabine (Myrtaceae) are new naturalised records and Crepidomanes saxifragoides (C.Presl) P.S.Green (Hymenophyllaceae) is an addition to the indigenous flora. Crepidomanes is a new genus for the indigenous flora of Niue. Information is provided for each of these species on their biostatus, collections, distribution and habitats. Erigeron bellioides is known from several locations that provide access to sea and chasm walks where it mostly occupies disturbed and grassy habitats used for car parks. It is most probably being spread by seeds adhering to tourists’ footwear and vehicle tyres as they move between popular attractions. In contrast, Psidium cattleyanum is known from a single plant on the margin of regenerating secondary forest along the Puluhiki Sea Track (Lakepa). It is unlikely to have been planted at this site and may be cultivated in the nearby Lakepa village, which could be the seed source for the established wild plant. Psidium cattleyanum is an invasive species on other Pacific Islands and we recommend removal of the single known plant and survey for it elsewhere, including gardens of the villages. Crepidomanes saxifragoides is known from a single collection in primary forest of the Huvalu Forest Conservation Area where it grew on the shaded and moist surface of a root buttress at the base of a trunk of Syzygium. [ABSTRACT FROM AUTHOR]

Introduction: As a soil amendment, Bamboo charcoal helps to contributes to the improvement of soil carbon sequestration, but its effect on the accumulation and transformation of different soil organic carbon in soil of karst forests is not clear. Methods: The research focused on three distinct forest land succession stages: virgin forest, secondary forest, and planted forest. A 60-day indoor constant temperature culture experiment was conducted, applying bamboo charcoal to the soil of the three forest lands at four different addition ratios: 0%, 1.0%, 2.0%, and 4.0%. The analysis aimed to study the characteristics of SOC mineralization, different carbon fractions of organic carbon, and soil enzyme activity. Results: The findings revealed that bamboo charcoal application led to an increase in the organic carbon (SOC) content within the three forest soils. Moreover, the organic carbon content showed an increase corresponding to the increased proportion of bamboo charcoal, with the highest SOC content observed in the planted forest land with 4.0% bamboo charcoal. The overall performance of the C0/SOC value in the three forest soils was ranked as follows: planted forest < secondary forest < virgin forest (C0: the mineralization potential of soil organic carbon). In both planted and secondary forest soils, the C0/SOC value increased after the application of bamboo charcoal. However, in the virgin forest soil, the application of 1.0% and 4.0% bamboo charcoal reduced the C0/SOC value, while the application of 2.0% bamboo charcoal increased the C0/SOC value. Particularly the C0/SOC value of the planted forest soil without bamboo charcoal was the smallest at 0.047, whereas that in the virgin forest soil with 2.0% bamboo charcoal had the largest value at 0.161. Discussion: Herein, appropriate human intervention can enhance the carbon sequestration potential of forest soil, in different succession stages within the karst area. However, the external application of bamboo charcoal does not significantly improve the carbon sequestration potential in the planted and secondary forest. Notably, applying a higher proportion (4.0%) of bamboo charcoal can enhance the organic carbon sequestration potential, particularly in the virgin forest soil, representing the climax community of forest succession. [ABSTRACT FROM AUTHOR]

Passive restoration of secondary forests can partially offset loss of biodiversity following tropical deforestation. Tree cavities, an essential resource for cavity-nesting birds, are usually associated with old forest. We investigated the restoration time for tree cavities suitable for cavity-nesting birds in secondary forest at the Biological Dynamics of Forest Fragments Project (BDFFP) in central Amazonian Brazil. We hypothesized that cavity abundance would increase with forest age, but more rapidly in areas exposed to cutting only, compared to areas where forest was cut and burned. We also hypothesized that cavities would be lower, smaller, and less variable in secondary forest than in old-growth forest, which at the BDFFP is part of a vast lowland forest with no recent history of human disturbance. We used pole-mounted cameras and tree-climbing to survey cavities in 39 plots (each 200 × 40 m) across old-growth forests and 11–34-year-old secondary forests. We used generalized linear models to examine how cavity supply was related to forest age and land-use history (cut only vs cut-and-burn), and principal components analysis to compare cavity characteristics between old-growth and secondary forest. Cavity availability increased with secondary forest age, regardless of land-use history, but the oldest secondary forest (31–34 years) still had fewer cavities (mean ± SE = 9.8 ± 2.2 cavities ha–1) than old-growth forest (20.5 ± 4.2 cavities ha–1). Moreover, secondary forests lacked cavities that were high and deep, with large entrances—characteristics likely to be important for many species of cavity-nesting birds. Several decades may be necessary to restore cavity supply in secondary Amazonian forests, especially for the largest birds (e.g. forest-falcons and parrots > 190 g). Retention of legacy trees as forest is cleared might help maintain a supply of cavities that could allow earlier recolonization by some species of cavity-nesting birds when cleared areas are abandoned. A Portuguese version of this article is available in Supplementary Material 1. [ABSTRACT FROM AUTHOR]

Juglans mandshurica is an important component of Korean pine mixed and secondary forests in Northeast China and is also a precious timber and economic species. In this study, plant regeneration of J. mandshurica has been established using stems with bud and mature zygotic embryos as explants. The results showed that placing the stems with buds in low-temperature conditions (0 to 4°C) and in darkness for 5 d inhibited the browning of the explants and promoted bud sprouting; Na2S2O3 also inhibited the browning of mature zygotic embryos significantly. The suitable basal media and hormones for bud sprouting and zygotic embryo germination were (1) WPM medium (woody plant medium) containing 2.0 mg·L−1 6-benzylaminopurine (6-BA) and 0.01 mg·L−1 3-indolebutyric acid (IBA) and (2) DKW medium (Driver and Kuniyuki medium) containing 2.5 mg·L−1 6-BA and 0.1 mg·L−1 IBA. The suitable basal medium and hormone for rooting of shoots from buds was 1/2 Murashige and Skoog (MS) medium (the macro-elements were half-strength of MS medium) supplemented with 1.0 mg·L−1 IBA, and the suitable basal medium and hormone for rooting of seedlings derived from zygotic embryo was 1/2 MS medium containing 1.0 mg·L−1 IBA, and DKW medium with 2.5 mg·L−1 6-BA, 0.1 mg·L−1 IBA, 0.2 mg·L−1 gibberellin A3 (GA3), and 0.2 g·L−1 activated carbon (AC). About 95% of the rooted plantlets survived after acclimation and transplantation. These results provided a foundation for the scale propagation to meet the demands of forestry production of the species. [ABSTRACT FROM AUTHOR]

Improving our ability to monitor fragmented tropical ecosystems is a critical step in supporting the stewardship of these complex landscapes. We investigated the structural characteristics of vegetation classes in Ucayali, Peru, employing a co‐production approach. The vegetation classes included three agricultural classes (mature oil palm, monocrop cacao, and agroforestry cacao plantations) and three forest regeneration classes (mature lowland forest, secondary lowland forest, and young lowland vegetation regrowth). We combined local knowledge with spaceborne lidar from NASA's Global Ecosystem Dynamics Investigation mission to classify vegetation and characterize the horizontal and vertical structure of each vegetation class. Mature lowland forest had consistently higher mean canopy height and lower canopy height variance than secondary lowland forest (μ = 29.40 m, sd = 6.89 m vs. μ = 20.82 m, sd = 9.15 m, respectively). The lower variance of mature forest could be attributed to the range of forest development ages in the secondary forest patches. However, secondary forests exhibited a similar vertical profile to mature forests, with each cumulative energy percentile increasing at similar rates. We also observed similar mean and standard deviations in relative height ratios (RH50/RH95) for mature forest, secondary forest, and oil palm even when removing the negative values from the relative height ratios and interpolating from above‐ground returns only (mean RH50/RH95 of 0.58, 0.54, and 0.53 for mature forest, secondary forest, and oil palm, respectively) (p <.0001). This pattern differed from our original expectations based on local knowledge and existing tropical forest succession studies, pointing to opportunities for future work. Our findings suggest that lidar‐based relative height metrics can complement local information and other remote sensing approaches that rely on optical imagery, which are limited by extensive cloud cover in the tropics. We show that characterizing ecosystem structure with a co‐production approach can support addressing both the technical and social challenges of monitoring and managing fragmented tropical landscapes. [ABSTRACT FROM AUTHOR]

Soil fungi participate in various ecosystem processes and are important factors driving the restoration of degraded forests. However, little is known about the changes in fungal diversity and potential functions under the development of different vegetation types during natural (secondary forest succession) and anthropogenic (reforestation) forest restoration. In this study, we selected typical forest succession sequences (including Pinus densiflora Siebold & Zucc., pine‐broadleaf mixed forest of P. densiflora and Quercus acutissima Carruth., and Q. acutissima), as well as natural secondary deciduous broadleaved mixed forests and planted forests of Robinia pseudoacacia on Kunyu Mountain for analysis. We used ITS rRNA gene sequencing to characterize fungal communities and used the FUNGuild database to predict fungal functional groups. The results showed that forest succession affected fungal β‐diversity, but not the α‐diversity. There was a significant increase in Basidiomycota and a decrease in Ascomycota in the later successional stage, accompanied by an increase in the functional groups of ectomycorrhizal fungi (ECM). Conversely, planted forests exhibited decreased fungal α‐diversity and altered community compositions, characterized by fewer Basidiomycota and more Ascomycota and Mucoromycota. Planted forests led to a decrease in the relative abundances of ECM and an increase in animal pathogens. The TK content was the major factor explaining the distinction in fungal communities among the three successional stages, whereas pH, AP, and NH4+ were the major factors explaining community variations between natural and planted forests. Changes in vegetation types significantly affected the diversity and functional groups of soil fungal communities during forest succession and reforestation, providing key insights for forest ecosystem management in temperate forests. [ABSTRACT FROM AUTHOR]

The role of the roots and root systems of Pinus sylvestris L. in the formation of secondary pine forests in the cuttings of the Kola North was studied. It has been established that in pine seedlings in disturbed areas, root and shoot systems are formed quite quickly. Already in age class I, characteristic morphological signs of root systems appear and the feeding areas of trees begin to overlap each other. The bulk of the roots (80–85%) is concentrated in the upper 20-cm soil layer. A linear relationship between the taxation indicators of trees and the mass of root systems has been revealed. The conducted studies have shown that the formation of forest communities of Scots pine in the cuttings of the Kola North and their stability and productivity are directly dependent on the degree of development of individual roots and root systems as a whole. [ABSTRACT FROM AUTHOR]

Broad-leaved monocot herbs form one of the most common and diverse growth forms of Neotropical plants. Their significance and frequency of occurrence is particularly notable in the understories of tropical rainforests, where they form a dominant element. We assessed and quantified changes in the cover and diversity of understory herb communities in a chronosequence of 1 ha permanent plots established as part of a multidisciplinary study on tropical forest regeneration in the Atlantic lowlands of northeastern Costa Rica. Sampled were two young stands cleared 12 years ago, two secondary forests with 21 and 39 of years of recovery since clearance, and two stands in old-growth primary forest. Changes in species composition during succession were assessed using Chao's Jaccard similarity index. Observed species richness ranged from 15 to 26 species in individual plots, with the greatest number of species in the 21-year intermediate-age and fewest in the young 12-year plots. Herb species sampled represented 6 families, 15 genera, and 39 species, with the Araceae contributing the largest number of species. Ten species were sampled in all six stands, while fourteen species were found exclusively in one plot. Herb density (ramets m−2) showed a hump-shade trend, with peak density in the intermediate stands and a lower level in mature and young secondary forests. Mean herb cover in 25 m2 quadrats ranged from 2.0% (young stand) to 22.7% (intermediate-age stand) and differed significantly both among stand types and among sites. Both observed and estimated species richness increased along the chronosequence as a whole, with the highest number of species in primary forest, although only slightly higher than in intermediate-age stands. Over half of the species exhibited some degree of clonal growth, with the extent of clonal spread varying among species and forest stands. Although we did not find a clear pattern between clonality and forest age, we observed a greater number of clonal patches in secondary over primary forest stands. [ABSTRACT FROM AUTHOR]

Our aim was to evaluate whether the richness and composition of anurans responded to the time of forest regeneration via secondary succession. We sampled the anuran community in a mosaic of areas at three different stages of secondary succession in the Atlantic Forest, southern Brazil. The anurans were collected from nine lentic ponds and from their margins up to a 50 m radius. The late secondary forest sheltered the higher species richness, followed by the primary forest. The spatial variation in species richness was related to the forest succession stage and predominance of arboreal vegetation on the pond edge. The species composition changed throughout the succession stages, regardless of the distance among areas. Along the gradient of forest succession, environmental changes have driven species distribution, limiting the occurrence of forest species and favoring the colonization of areas at the early succession stage by opportunist species. We could observe that the secondary forest succession was a determining factor in the anuran community structure, and with the advancement of the secondary succession, both richness and composition were partly restored. Thus, the conservation of secondary forests might be an efficient strategy to preserve the biodiversity in areas of the Atlantic Forest. [ABSTRACT FROM AUTHOR]

Tropical forests play an important role in ecosystem services, yet anthropological activities have changed the ecological conditions. Thus, this research was designed to reveal the species richness and diversity in secondary forests, including the lifeform alteration. The 50 perpendicular plots were placed in both forests and distributed 25 for each. The study revealed that the secondary forest represents a stage of ecological succession in which species richness and diversity decreased. Additionally, the composition of life forms in the secondary forest changed, with dominant herbs indicating more dynamic vegetation due to shifting ecological conditions. Species classified as Threatened have disappeared due to human activities in the forest. However, the secondary forest has provided a habitat for certain species, including those with conservation status, such as Threatened or Extinct, to thrive and colonize, where approximately 15.7% of species exclusively thrive in secondary forests, including Antiaropsis uniflora C.C.Berg. Therefore, to promote sustainable forest management, this study suggests monitoring the species in secondary forests, particularly since the use of forests has traditionally been determined by local communities, including in restricted forest areas. Moreover, the local government could officially designate traditional forest use, thereby allowing restricted forests to be conserved as old-growth forests. [ABSTRACT FROM AUTHOR]

The high Andean mountains are ecosystems subject to high human pressure activities, resulting in disturbed areas increasingly dominating the landscapes. However, there needs to have more knowledge about the contributions of different vegetation coverages and species to global diversity at the local level. For three consecutive years, we studied a guild of fruit-feeding butterflies in four different land covers (cloud forests, paramo, mixed anthropogenic habitats, and cattle pastures) in the northern Andes in Colombia, analyzing the diversity and structure of the butterfly assemblage in the region. The assembly showed significant differences between land covers. The mixed habitat was the most diverse in order q1 (exponential of Shannon entropy) and q2 (inverse of Gini-Simpson dominance index) diversity, and the cloud forest contained the higher abundance and species richness. Abundance decreased from forest to pasture, significantly reducing diversity in pastures, with cloud forest and paramo containing the key endemic species. These results indicate the value of landscape diversity in providing resources and conditions required for the diversity conservation of high Andean butterflies. Implications for insect conservation: This study highlights the significance of the heterogeneity of natural landscape components in maintaining and preserving the diversity of butterfly assemblages in high Andean environments. Current conservation plans often tend to focus on paramo habitats, our findings highlight the crucial role of including the surrounding cloud forest and associated secondary forest in the design of effective conservation strategies. The analysis revealed a high complementarity between paramo and cloud forest assemblages, with each habitat type contributing significantly to the regional species pool. This underscores the interconnectedness and interdependence of these habitats, indicating that a comprehensive approach that considers both paramo and cloud forest ecosystems is essential for conserving the full diversity of butterfly species in the region. Moreover, our results demonstrate that cattle pastures exhibit extremely low butterfly species richness and possess a community structure that is distinctly different from native habitats. [ABSTRACT FROM AUTHOR]

The semiarid grasslands of Argentina's central region have been modified by domestic livestock grazing, both in their composition and structure. The increase in the proportion of woody and non-forage species and the decrease in forage species are some of the most evident results of this process. There is limited available information about the effect of differential grazing pressures on morphometric attributes of native species, and it also depends on the life histories of the species in this grassland. The objective of this work was to evaluate some morphometric aspects in the grasses Poa ligularis Nees ex Steud and Piptochaetium napostaense (Speg.). Hack according to distance from the water source in communities in the central semiarid region of Argentina. The study area included areas of low grassland, golden forests, and secondary forests in grasslands (6 fields with 9 paddocks). Grazing pressure was established based on the distance to the water source, so sampling areas were designated near the water source (grazing pressure is greater) and far from the water source (grazing pressure light) in each of the pastures. In both species, specimens were selected at random, and the following attributes were measured: crown diameter at ground level (cm), burial depth (cm), average tiller weight per plant (g. Marcello−1), and the density of tillers per unit of crown surface (tillers.cm−2crown). The morphometric attributes evaluated showed differences according to the distance to the watering hole and in the different pastures. Both species presented similar behaviors for the attributes. There were significant differences in the depth of burial and the average weight of tillers per plant, being greater in the areas close to the water source. Regarding the distance to the watering hole, there were no significant differences in crown diameter and tiller density, but the highest values were recorded for the former near the watering hole and for the second far from the watering hole. In pastures with low grassland or secondary forest on the plain, the greatest depth of burial and weight of tillers was recorded closer to the water. In forest areas, the highest density of tillers was found far from the water. For crown diameter, although there was no interaction, the largest diameters were found in plain grassland areas near the waterhole. In general, both species had a differential behavior depending on the grazing pressure that was evident along the physiognomic gradient from plain grassland to forest and that could be interpreted as a strategy to perpetuate themselves against herbivory. [ABSTRACT FROM AUTHOR]