Native Tree Research Articles

Exploring the inhibitory activity and mechanism on lipid production in 3T3-L1 cells by hot water extract derived from Acacia confusa flowers.

Acacia confusa Merr. (Fabaceae) (A. confusa) is a native tree species of Taiwan, commonly found in the low-altitude mountains and hilly areas of the Hengchun Peninsula. This evergreen, perennial, and large-sized tree was the focus of a study that employed various chromatographic and spectroscopic methods to analyze the hot water extract of its flowers. The analysis revealed that the major components of the extract were myricitrin, quercitrin, europetin-3-O-rhamnoside, and chalconaringenin-2'-xyloside, with respective concentrations of approximately 0.22, 0.02, 0.26, and 0.10mg/g of the flowers. Subsequent cell assays were conducted to assess the inhibitory effect of the extract on lipid synthesis in fat cells. Oil Red O staining results indicated that the extract significantly suppressed fatty acid accumulation in 3T3-L1 cells, with the most pronounced effect observed at a concentration of 180μg/ml. Furthermore, the hot water extract of A. confusa flowers was found to increase the phosphorylation of AMP-activated protein kinase (AMPK), decrease the phosphorylation of cAMP response element-binding protein (CREB), and reduce the expression of glucocorticoid receptor (GR) protein. This, in turn, inhibited the expression of downstream transcription factors such as CCAT/ehancer binding proteins α (C/EBPα), CCAT/ehancer binding proteins β (C/EBPβ), CCAT/ehancer binding proteins δ (C/EBPδ), peroxisome proliferation-actived receptor γ (PPARγ), and sterol regulatory element binding proteins-1 (SREBP-1). Consequently, the expression of lipid synthesis-related proteins acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and fatty acid translocase (CD36) was reduced, ultimately inhibiting lipid generation. Therefore, the hot water extract of A. confusa flowers shows potential for development as a weight-loss tea.

Planting native trees in degraded grassy woodland does not restore species composition

SummaryRestoration of degraded former Cumberland Plain Woodland by planting of native trees and shrubs was undertaken by Greening Australia (NSW) on the Cumberland Plain, west of Sydney, Australia, from the mid‐1990s. Our study examined the success of this restoration in stands of two ages using species composition as the criterion. The starting point (pasture) and the target (reference woodland) were sampled to document the extent of progress of species composition from pasture through young (3–5 years) and old (9–11 years) restoration stands to reference woodland across three sites at two surveys. Comparisons showed restored stands of both ages differed significantly from pasture, and from each other, showing decreasing similarity between the restoration stands and pasture at all sites. Despite this, species composition in restored stands at all three sites was still significantly different from reference sites, showing that none had achieved the target reference state after 11 years. The trajectory of restored sites between the two surveys was not towards the reference state. Restoration resulted in the establishment of 20 (71%) of the planted species. Recruits from five planted species were found. A further 40 unplanted native ground layer species were found in restoration. Structurally, tree cover increased with time since restoration and was higher in the restored sites. Ground cover, which was very high in pasture was lower in some restored sites. The majority of the unplanted native species were resprouters, and their presence in the above‐ground vegetation was most likely by vegetative resprouting from the bud‐and‐tuber bank as ground cover was lower with the increase in tree cover and shade. Tree and shrub planting by itself has not yet progressed the restored areas to the species composition of reference sites. Additional tools will be needed to assist restoration, specifically the addition of re‐seeder native plants not able to persist through vegetative resprouting after restoration. Measures to control the burden of weeds present in the pasture seed bank are also required.

Natural frequency tree- versus conditional probability formula-based training for medical students’ estimation of screening test predictive values: a randomized controlled trial

BackgroundMedical students and professionals often struggle to understand medical test results, which can lead to poor medical decisions. Natural frequency tree-based training (NF-TT) has been suggested to help people correctly estimate the predictive value of medical tests. We aimed to compare the effectiveness of NF-TT with conventional conditional probability formula-based training (CP-FT) and investigate student variables that may influence NF-TT’s effectiveness.MethodsWe conducted a parallel group randomized controlled trial of NF-TT vs. CP-FT in two medical schools in South Korea (a 1:1 allocation ratio). Participants were randomly assigned to watch either NF-TT or CP-FT video at individual computer stations. NF-TT video showed how to translate relevant probabilistic information into natural frequencies using a tree structure to estimate the predictive values of screening tests. CP-FT video showed how to plug the same information into a mathematical formula to calculate predictive values. Both videos were 15 min long. The primary outcome was the accuracy in estimating the predictive value of screening tests assessed using multiple-choice questions at baseline, post-intervention (i.e., immediately after training), and one-month follow-up. The secondary outcome was the accuracy of conditional probabilistic reasoning in non-medical contexts, also assessed using multiple-choice questions, but only at follow-up as a measure of transfer of learning. 231 medical students completed their participation.ResultsOverall, NF-TT was not more effective than CP-FT in improving the predictive value estimation accuracy at post-intervention (NF-TT: 87.13%, CP-FT: 86.03%, p = .86) and follow-up (NF-TT: 72.39%, CP-FT: 68.10%, p = .40) and facilitating transfer of training (NF-TT: 75.54%, CP-FT: 71.43%, p = .41). However, for participants without relevant prior training, NF-TT was more effective than CP-FT in improving estimation accuracy at follow-up (NF-TT: 74.86%, CP-FT: 58.71%, p = .02) and facilitating transfer of learning (NF-TT: 82.86%, CP-FT: 66.13%, p = .04).ConclusionsIntroducing NF-TT early in the medical school curriculum, before students are exposed to a pervasive conditional probability formula-based approach, would offer the greatest benefit.Trial registrationKorea Disease Control and Prevention Agency Clinical Research Information Service KCT0004246 (the date of first trial registration: 27/08/2019). The full trial protocol can be accessed at https://cris.nih.go.kr/cris/search/detailSearch.do?seq=15616&search_page=L.

Copaiba Oleoresin Improves Weight Gain and IL-10 Concentration, with No Impact on Hepatic Histology, in Liver Cirrhosis

Copaifera sp. is a native tree in the Amazon region. Copaiba oleoresin has components such as sesquiterpenes, which have anti-inflammatory and antioxidant potential. Liver cirrhosis is the end stage of liver disease with limited therapeutic options. We aimed to evaluate the effect of copaiba oleoresin supplementation on the liver of animals with thioacetamide (TAA)-induced cirrhosis. For the induction of liver cirrhosis, 100 mg/kg of TAA was administered intraperitoneally twice a week for 8 weeks. A total of 200 mg/kg/day of copaiba oleoresin was administered via gavage for the same period. Copaiba oleoresin supplementation improved cirrhosis-associated cachexia by increasing weight gain and body fat. In addition, copaiba oleoresin attenuated systemic inflammation, as shown by the decrease in the circulating C-reactive protein. In the liver, the copaiba oleoresin decreased carbonyl proteins and increased IL-10 compared with TAA-treated rats. TAA groups demonstrated increased SOD, catalase, GST, and GSH activity in the liver. In conclusion, the supplementation of copaiba oleoresin demonstrated a beneficial systemic effect in alleviating cirrhotic cachexia and antioxidant and anti-inflammatory action in the liver. However, it failed to improve the serological and histological markers of liver damage, which could be associated with the advanced stage of the disease.

Allelopathic Effects of Vachellia nubica, Vachellia tortilis and Hyphaene compressa on Germination and Seedling Growth of Prosopis juliflora

Background: Prosopis juliflora (Sw.) DC is an invasive species negatively impacting plant ecology and livelihoods in introduced areas. Native tree species may produce allelochemicals that can inhibit growth of invasive species, resulting in a natural management technique. Aim: This study aimed to determine allelopathic effect of three native tree species (V. tortilis, V. nubica, and H. compressa) on seed germination and early seedling growth of P. juliflora to identify the tree species that can be used to suppress P. juliflora invasion as part of its management strategy. Methodology: Crude Leaf and root extracts of the native trees at 0%, 1%, 2.5%, 5%, and 10% concentrations were prepared. P. juliflora seeds were subjected to 24 crude extract treatments and a control in a completely randomized design in Petri dishes. The seeds were uniformly moistened with 10 ml extracts daily in a germination chamber for 14 days, and germination counts were done after every 2 days. Shoot and root length and wet weight were measured after 14 days. The data were subjected to three-way ANOVA and means separated by Tukey. Results: Prosopis seed coats treated with V. tortilis and V. nubica leaf extracts turned darkish before germination while germination of seeds in 10% leaf extracts of V. nubica aborted. Seed germination percentage in 10% leaf extracts of V. tortilis (30%) and V. nubica (23%) were the lowest compared to control (90%). P. juliflora seedlings under 5% V. nubica and 10% V. tortilis died before the experiment period. Depending on crude extract concentrations, percent inhibition on germination characteristics were; percent germination (21-74%), wet weight (6-49%), plumule length (10-47%), and radicle length (7-86%) of germinating P. juliflora. Conclusion: The native tree species studied have allelopathic effects on the germination of P. juliflora and thus can be promoted to suppress invasiveness of P. juliflora.

Invasive shrub removal may be more effective at reducing granivory than coating tree seeds with capsaicin

The utility of seed addition to promote tree regeneration can be greatly limited by animals that consume seeds. Moreover, given that restoration often occurs in forests where invasive shrubs are abundant, and evidence that invasive shrubs can increase granivory, it is important to explore whether methods for reducing granivory work equally well in invaded and uninvaded habitats. We used a multi-site field experiment spanning 160 days to explore whether coating seeds of Prunus serotina with capsaicin extract leads to reduced granivory in habitats with or without invasive shrubs (Rhamnus cathartica). Capsaicin-coated seeds were removed at a similar rate to uncoated seeds, but seeds in invaded plots had a 78.8% higher rate of removal compared to plots without invasive shrubs. Our findings suggest that managers seeking to encourage regeneration of native trees using direct seeding should consider invasive shrub removal as a top priority to limit the loss of seeds once sown.

Assessing the impact of urban parks across Köppen climatic zones: a systematic review

This review article addresses the gap in the literature concerning the role of urban parks in providing cooling effects in hot and arid climatic zones. Using systematic review and content analysis of manuscripts from 1999 to 2023 in Scopus and Web of Science databases, elements and indicators of landscape architecture and their impacts on mitigating urban heat islands (UHI) have been explored. Our data mining revealed 190 manuscripts categorized into four Köppen climatic zones: tropical/mega thermal, arid, temperate/mesothermal, and continental/microthermal. Results indicate a scarcity of studies on hardscape elements’ impact, particularly in desert and semi-arid zones, and limited recognition of landscape architecture’s role in urban park cooling, especially in hot desert climates. Green areas emerged as the most cost-effective cooling strategy, with grass planted to minimize water elements and enhance tree cooling effects. However, the lack of softscape in hot, arid zones poses a significant challenge in mitigating UHI. These findings bridge the literature gap and suggest avenues for future research, including investigating native urban tree species and optimizing park area, shape, and orientation.

Forest and Biodiversity 2: A tree diversity experiment to understand the consequences of multiple dimensions of diversity and composition for long‐term ecosystem function and resilience

Abstract We introduce a new “ecosystem‐scale” experiment at the Cedar Creek Ecosystem Science Reserve in central Minnesota, USA to test long‐term ecosystem consequences of tree diversity and composition. The experiment—the largest of its kind in North America—was designed to provide guidance on forest restoration efforts that will advance carbon sequestration goals and contribute to biodiversity conservation and sustainability. The new Forest and Biodiversity (FAB2) experiment uses native tree species in varying levels of species richness, phylogenetic diversity and functional diversity planted in 100 m2 and 400 m2 plots at 1 m spacing, appropriate for testing long‐term ecosystem consequences. FAB2 was designed and established in conjunction with a prior experiment (FAB1) in which the same set of 12 species was planted in 16 m2 plots at 0.5 m spacing. Both are adjacent to the BioDIV prairie‐grassland diversity experiment, enabling comparative investigations of diversity and ecosystem function relationships between experimental grasslands and forests at different planting densities and plot sizes. Within the first 6 years, mortality in 400 m2 monoculture plots was higher than in 100 m2 plots. The highest mortality occurred in Tilia americana and Acer negundo monocultures, but mortality for both species decreased with increasing plot diversity. These results demonstrate the importance of forest diversity in reducing mortality in some species and point to potential mechanisms, including light and drought stress, that cause tree mortality in vulnerable monocultures. The experiment highlights challenges to maintaining monoculture and low‐diversity treatments in tree mixture experiments of large extent. FAB2 provides a long‐term platform to test the mechanisms and processes that contribute to forest stability and ecosystem productivity in changing environments. Its ecosystem‐scale design, and accompanying R package, are designed to discern species and lineage effects and multiple dimensions of diversity to inform restoration of ecosystem functions and services from forests. It also provides a platform for improving remote sensing approaches, including Uncrewed Aerial Vehicles (UAVs) equipped with LiDAR, multispectral and hyperspectral sensors, to complement ground‐based monitoring. We aim for the experiment to contribute to international efforts to monitor and manage forests in the face of global change.

Seed size and <i>Azospirillum brasilense</i> Ab-V5 and Ab-V6 inoculation influences germination and early seedling vigor of <i>Acacia mearnsii</i>

Acacia mearnsii is an Australian native tree species commercially grown in Africa and South America that produces tannins and woodchips. Its seed size varies, which may impact the germination and initial growth of seedlings. In its turn, Azospirillum brasilense inoculation is known to improve the growth of several crops. However, there are few studies the effects of A. brasilense inoculation on the germination and initial growth of forestry species. The present study evaluated the influence of seed size and A. brasilense Ab-V5 and Ab-V6 inoculation on germination and initial growth of A. mearnsii. Small seeds reduced the mean germination time (MGT) by 5.2% and the time to 50% germination (T50) by 23.8% in comparison to large seeds. On the other hand, seedlings that originated from large seeds had a seedling vigor index (SVI) 18.6% higher than those that originated from small seeds. Azospirillum brasilense inoculation increased the germination percentage by 20.9%, germination speed by 91.8%, root length (RL) by 35.8%, and root fresh weight by 20.5%. Additionally, it decreased MGT by 8.2% and T50 by 37.6%. The combination of large seeds and A. brasilense inoculation increased RL by approximately 50% and SVI by 62.1%. Thus, the use of A. brasilense inoculation favors germination and seedling vigor in A. mearnsii, showing to be a promising strategy for obtaining more uniform seedlings in forest nurseries.

Restoring native forests from Pinus radiata plantations: natural regeneration of native tree species in response to different harvesting treatments in central Chile

The natural forests of south‐central Chile are known as world biodiversity hotspot. Due to increasing societal demands and certification commitments, a vast extension of these forests that was replaced by commercial exotic tree plantations is now to be restored. Given the magnitude of the area involved, large‐scale approaches based on natural regeneration require consideration. However, experimental evidence for this approach to restoration is lacking in different regions. We conducted a large‐scale replicated experiment to evaluate the response of natural regeneration of native tree species to different harvesting treatments (clearcut, strip‐cutting, and unharvested control) in 20‐year‐old Pinus radiata plantations. For 2 years, we monitored variations in (1) regeneration basal area (dRBA), (2) maximum sapling height (dMH), (3) frequency of free‐growing regeneration (dFGR), and (4) diversity of regenerating tree species. The harvesting treatment had significant effects on dRBA, dMH, and dFGR. The clearcuts showed the highest values of dRBA and dFGR of native species, but also, the highest dRBA of P. radiata regeneration. The strip‐cuttings showed the highest dMH of native species and the highest values of richness, Shannon, and Simpson diversity. Our results suggest that both clearcuts and strip‐cuttings facilitate natural regeneration. Although clearcuts may allow higher rates of natural regeneration establishment than strip‐cuttings, they require periodic control of P. radiata regeneration to prevent suppression of established native regeneration. Strip‐cuttings may require fewer management interventions and allow for higher initial species diversity, although with a potentially longer establishment period and higher risk of damage from residual P. radiata trees experiencing wind throw.

Energy Constrained Depth First Search

AbstractDepth first search is a natural algorithmic technique for constructing a closed route that visits all vertices of a graph. The length of such a route equals, in an edge-weighted tree, twice the total weight of all edges of the tree and this is asymptotically optimal over all exploration strategies. This paper considers a variant of such search strategies where the length of each route is bounded by a positive integer B (e.g. due to limited energy resources of the searcher). The objective is to cover all the edges of a tree T using the minimum number of routes, each starting and ending at the root and each being of length at most B. To this end, we analyze the following natural greedy tree traversal process that is based on decomposing a depth first search traversal into a sequence of limited length routes. Given any arbitrary depth first search traversal R of the tree T, we cover R with routes $$R_1,\ldots ,R_l$$ R 1 , … , R l , each of length at most B such that: $$R_i$$ R i starts at the root, reaches directly the farthest point of R visited by $$R_{i-1}$$ R i - 1 , then $$R_i$$ R i continues along the path R as far as possible, and finally $$R_i$$ R i returns to the root. We call the above algorithm piecemeal-DFS and we prove that it achieves the asymptotically minimal number of routes l, regardless of the choice of R. Our analysis also shows that the total length of the traversal (and thus the traversal time) of piecemeal-DFS is asymptotically minimum over all energy-constrained exploration strategies. The fact that R can be chosen arbitrarily means that the exploration strategy can be constructed in an online fashion when the input tree T is not known in advance. Each route $$R_i$$ R i can be constructed without any knowledge of the yet unvisited part of T. Surprisingly, our results show that depth first search is efficient for energy constrained exploration of trees, even though it is known that the same does not hold for energy constrained exploration of arbitrary graphs.

Preparation and characterization of a Pickering oil-in-water emulsion based on TiO2 coated with phytochemicals derived from the bark of a native Argentine tree

Micron-sized Pickering oil-in-water emulsions (POWEs) were prepared by ultrasonically mixing olive oil (OO) as the dispersed organic phase, laponite XLG (LAP) as the emulsion stabilizer, and with TiO2 nanoparticles uncoated or coated with phytochemicals present in an aqueous extract of bark from the Argentine native tree Schinopsis lorentzii (TiO2@SL). Polyphenolic and tannic acids and flavonoids were identified as the major phytochemicals forming the TiO2@SL coating. The two types of POWEs with different compositions were prepared according to a full factorial design model with two factors and three levels, and the POWEs with the smallest droplet size and greater stability were selected for further characterization by several techniques. Despite their high hydrophilicity, confocal Raman and scanning electron microscopies confirmed that both types of nanoparticles were forming the interface of the emulsion. Viscosity, spreadability, and microdroplet size determinations show that both POWEs exhibit pseudoplastic fluid behavior with excellent spreading ability and long-term stability. In comparison to the emulsion formulated with uncoated TiO2, the TiO2@SL-based POWE did not demonstrate UV-induced photocatalytic degradation of organic dyes and exhibited an enhanced sun protection factor. These findings were attributed to the UV-filtering and antioxidant capabilities of the polyphenolic compounds that constitute the coating of the TiO2 nanoparticles. This study demonstrates the potential of utilizing residual forest resources to prepare valuable modified TiO2 nanocomposites, which may be suitable for the formulation of cosmetic products without the risk of phototoxicity.

Contrasting Life-Form Influences Guam Ficus Foliar Nutrient Dynamics

Tropical trees that remain evergreen and exhibit leaf litterfall that is gradual over time coexist with trees that are seasonally deciduous and exhibit pulsed litterfall. The manner in which these trees acquire, store, and contribute nutrients to the biogeochemical cycle may differ. Green and senesced leaves from deciduous Ficus prolixa trees were compared with those from Ficus tinctoria on the island of Guam. The results enabled stoichiometry and resorption calculations. F. prolixa’s young green leaf nitrogen (N) and potassium (K) concentrations were double, and the phosphorus (P) concentration was triple, those of F. tinctoria. Concentrations converged as the leaves aged such that no differences in concentration occurred for senesced leaves, indicating that nutrient resorption proficiency did not differ between the two species. In contrast, the resorption efficiency was greater for F. prolixa than F. tinctoria for all three nutrients. The N:P values of 6–11 and K:P values of 5–7 were greater for young F. tinctoria leaves than young F. prolixa leaves. The N:K values were 1.1–1.6 and did not differ between the two species. No differences in pairwise stoichiometry occurred for senesced leaves for any of the nutrients. These Guam results conformed to global trends indicating that seasonally deciduous plants are more acquisitive and exhibit greater nutrient resorption efficiency. The differences in how these two native trees influence the community food web and nutrient cycling lies mostly in the volume and synchronicity of pulsed F. prolixa litter inputs, and not in differences in litter quality. These novel findings inform strategic foresight about sustaining ecosystem health in Guam’s heavily threatened forests.

Five new species of endophytic Penicillium from rubber trees in the Brazilian Amazon.

The Amazon rainforest is the world's most diverse ecosystem, full of fauna and flora. Among the trees that make up the forest are the rubber trees of the genus Hevea (H. brasiliensis and H. guianensis), which stand out for the industrial use of latex. It was previously shown that endophytic fungi colonize the leaves, stems, and roots of Hevea spp. In this study, 47 Penicillium spp. and three Talaromyces spp. isolates were analyzed using specific DNA barcodes: internal transcribed spacers region (ITS), β-tubulin (BenA), calmodulin (CaM), and the DNA-dependent RNA polymerase II second largest subunit (RPB2) genes and additionally, for species delimitation, the genealogical concordance phylogenetic species recognition (GCPSR) criteria were applied. The phylogenetic analyses placed the Penicillium isolates into four sections Lanata-Divaricata, Sclerotiora, Citrina, and Fasciculata. The morphological and molecular characteristics resulted in the discovery of five new species (P. heveae sp. nov., P. acrean sp. nov., P. aquiri sp. nov., P. amazonense sp. nov., and P. pseudomellis sp. nov.). The five new species were also compared to closely related species, with observations on morphologically distinguishing features and colony appearances. Bayesian inference and maximum likelihood analysis have supported the placement of P. heveae sp. nov. as a sister group to P. globosum; P. acrean sp. nov. and P. aquiri sp. nov. as sister groups to P. sumatrense; P. amazonense sp. nov. closely related to isolates of P. rolfsii, and P. pseudomellis sp. nov. closely related to P. mellis. The study of endophytic Penicillium species of rubber trees and the description of five new taxa of Penicillium sect. Citrina, Lanata-Divaricata, and Sclerotiora as endophytes add to the fungal biodiversity knowledge in native rubber trees. Reports of fungi in native tropical plants may reveal taxonomic novelties, potential pathogen control agents, and producers of molecular bioactive compounds of medical and agronomic interest.

A chitosan-modified tea tree oil self-nanoemulsion improves antibacterial effects in vivo and in vitro and promotes wound healing by influencing metabolic processes against multidrug-resistant bacterial infections

Infectious diseases, especially multidrug-resistant bacterial infections, have caused crises and majorly disrupted public health and economic stability worldwide. Many natural essential oils, especially tea tree oil, have potential to treat multidrug-resistant bacteria, such as H. pylori and P. aeruginosa. However, there are some problems need to be solved, such as poor stability upon light or oxygen exposure. Therefore, it is urgent to develop the ideal formation to tackle these difficulties. Herein, we reported the novel chitosan-modified self-nanoemulsion (TNE) encapsulating natural essential tea tree oil with strong antibacterial and stability characterize. In this study, we found that this self-nanoemulsion (size: 212 nm, PDI: 0.124, zeta potential: −20.5 mV, 6 % tea tree oil) not only had physical properties, good stability and tissue safety, but also had better antibacterial synergism (2–8 times) than that of water suspension against various multidrug-resistant bacterial (such as H. pylori, MRSA and P. aeruginosa). Additionally, TNE showed high antibacterial effectiveness in vivo, reduced inflammation, promoted ulcer healing after H. pylori infection and accelerated wound healing after P. aeruginosa infection. Importantly, this novel self-nanoemulsion can induce 274 protein down-regulated and 251 protein up-regulated, and disrupt H. pylori metabolic processes (glyoxylate, dicarboxylic acid, glutamate and tryptophan metabolism) and reduced its viability, leading to significant synergistic antibacterial effects. TNE is a potential treatment for skin wounds or ulcers caused by multidrug-resistant bacterial infections.

Trends in planted native tree biomass established in a tropical Andes city water basins

Studying tree growth processes helps us evaluate the success of restoration efforts in recovering ecosystem processes such as carbon accumulation. Here, we study aboveground biomass dynamics in four common‐endemic tree species from the tropical Andes (Quercus humboldtii, Retrophyllum rospigliosii, Citharexylum subflavescens, and Croton magdalenensis), established in the main water supply basins of Medellín, Colombia. We use measurements from 19 permanent plots from five censuses between 2010 and 2023 to develop biomass equations as a function of t for each species (B = f[t]) by combining tree growth models of diameter (D) as a function of time (t) and pre‐existing allometric equations of biomass (B) developed in the same site as a function of D and wood density (ρ). We found that, because of initially higher growth rates characteristic of species belonging to the fast‐growing end of the fast‐slow growth economic spectrum, C. magdalenensis and C. subflavescens were the species with higher biomass accumulation at 13 years (142 and 132 kg, respectively). However, the potential of the slow‐growing species (Q. humboldtii and R. rospigliosii) for carbon sequestration initiatives in the long term was highlighted. To our knowledge, this is the first study in the region examining the dynamics of aboveground biomass in Andean restoration programs. It combines growth models and allometric equations, which can be useful for measuring the success of the implementation of ecological restoration programs and evaluating the need to apply adaptive management strategies.

Native tree promotes invasion when native grasses are absent

Despite the expected co‐occurrence of effects from resident species, the environment, and disturbance on non‐natives, these factors have largely been treated as acting separately. Co‐occurring factors may, however, act in combination to result in a powerful, yet little explored, mechanism of invasion. Here, we addressed three hypotheses to explain the localized invasion of the non‐native Chenopodium album (Chenopodium) under the canopy of the dominant native tree Neltuma caldenia (Neltuma) in central Argentina. First, we evaluated that Neltuma favors Chenopodium by modifying environmental conditions, and specifically assessed the importance of soil versus that of the microclimate created by Neltuma shade. Second, we tested that Neltuma benefits Chenopodium by promoting under its canopy (calden microsite) the dominance of a grass species, Nassella tenuissima (Nassella), that exerts weaker competitive effects on Chenopodium than those exerted by the dominant grass, Piptochaetium napostaense (Piptochaetium), in adjacent communities free of the tree (open microsite). Lastly, we explored that the invasion of Chenopodium is mediated by disturbance. Chenopodium displayed increased biomass and fecundity (performance) in soil from calden relative to that from open microsites, whereas it exhibited no response to shade treatments. Also, Chenopodium performance in pots with Nassella was similar to that in pots with Piptochaetium. Finally, Chenopodium performance was much greater in pots with no initial plants than in those with grasses. Importantly, in pots without plants, Chenopodium performed much better in calden than open microsites, but in pots with grasses, Chenopodium performance exhibited no differences between microsites. These findings suggest that disturbance mediates Chenopodium invasion in calden microsites. Specifically, disturbance may weaken strong competitive effects from native grasses on Chenopodium, allowing this non‐native herb to benefit from favorable soil conditions under Neltuma. The combined action of natives enhancing resource levels and disturbance providing access to them could be a general mechanism of invasion.

Spatio‐temporal variability in seed production of tree species: implications for restoration in the Cerrado–Amazonia transition zone

The use of propagules collected in ecotonal regions for restoration purposes is challenging because of the mix of species from different vegetation types and reproductive phenological variability. We used a database of the Xingu Seed Network in Brazil, which contains data on 139 native tree species for 8 years (2011–2018) in the Cerrado–Amazonia transition zone, to answer three questions: (1) What is the spatio‐temporal variability in the seed dispersal of tree species, and how does it relate to the species' preferential habitat? (2) Is there a relationship between the seed dispersal period and climate variables? (3) Is the frequency of tree species with different dispersal syndromes equally distributed among biomes and seed‐size classes? Independent of their preferred ecosystem (Amazonia or Cerrado), some species showed substantial spatio asynchrony in fruit dispersal, extending the dispersal period at a regional scale. The seed dispersal period was strongly correlated (rs > 0.6) with precipitation and minimum or maximum air temperature in 41% (n = 57) of the studied species. We showed that three‐quarters of the species (n = 105) dispersed seeds in the late dry and early rainy periods, with little variation among dispersal syndromes. Our findings will enhance the effectiveness of restoration initiatives by increasing the accuracy of predictions of the location and time for collecting seeds in the extensive Cerrado–Amazonia transition zone.

Building alliances and consensus around social-ecological rewilding in Chile

We provide a case study of how we position our rewilding project in central Chile in order to find scientific and social support and build alliances, collaborations, and consensus. Our core vision focuses on reintroducing guanacos (Lama guanicoe) to central Chile in order to provide natural restoration and ecosystem processes in espinal woodlands dominated by the native tree Vachellia [Acacia] caven. We envision a scenario of “social-ecological rewilding” with widespread guanaco browsing in woodlands and guanaco migration across the region, coexisting with multiple human uses of the landscape. Guanacos would ideally be managed by regional collectives who could benefit from guanaco tourism, sustainable harvest of their fiber (wool), and regulated hunting. Our wider vision for reintroductions and integrated conservation management extends to a set of other species that may have coexisted with guanacos and V. caven at various points in the past, but more research is necessary to establish and gain support for evidence-based baselines. Our strategy is to inspire actors with greater resources (land, money, influence) to share our vision and implement it, in collaboration with the NGO that we have formed to support our projects. Over ten years, circulating alternate interpretations and a novel imaginary of how central Chile was in the past and could be in the future, along with developing and testing scientific hypotheses, has moved our vision from an idea shared by two people to one that a wide variety of actors publicly embrace.

Bryophytes in managed lowland forests of Slovakia (Central Europe): looking into species diversity across different forest types

AbstractThe majority of the woodland area in Central Europe is composed of managed forests. Although the species diversity and composition, particularly in older forests, may be similar to those of natural or close-to-nature forests, intensive forestry and other human activities have adverse impacts on biodiversity. The present study focused on bryophyte diversity in managed lowland forests, as these have received less attention compared to other types of forests. Our research targeted the area located within the Borská nížina Lowland in south-western Slovakia. In total, 37 forest sampling plots (SPs) were selected, representing five different forest types, namely Quercus, Fraxinus, Robinia, Pinus, and mixed forests. Multivariate statistical analyses were conducted across these forest types to demonstrate variations in bryophyte species richness, composition, and functional traits. Overall, 60 species of bryophytes were identified, of which five were liverworts and 55 were mosses. Epiphytes were the most abundant substrate group in deciduous and mixed stands, while epigeic species prevailed in Pinus forests. Considering environmental factors, the bryophyte diversity was influenced mostly by the forest type and area size of SPs. Clear differences in species composition were observed when comparing coniferous and deciduous stands, as well as non-native Robinia forests and native tree stands. Overall, intensive forest management results in a high concentration of hemerophilous and nitrophilous species, along with the absence of rare and threatened mosses and liverworts. Nevertheless, by adhering to proper management methods, even managed forests can provide suitable habitats for various bryophytes.