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Smallholder farmers manage a significant portion of the world’s agricultural land, with smallholdings composing over 76% of agricultural land in Asia and 60% in Africa. By adopting assisted natural regeneration (ANR) practices, smallholder farmers and millions of land users across the global tropics and subtropics can become agents of restoration without having to abandon their farmland or rural livelihoods. Smallholder farmer...
Dominance and rarity in tree communities across the globe: Patterns, predictors and threatsNARA Subscribed
Aim Ecological and anthropogenic factors shift the abundances of dominant and rare tree species within local forest communities, thus affecting species composition and ecosystem functioning. To inform forest and conservation management it is important to understand the drivers of dominance and rarity in local tree communities. We answer the following research questions: (1) What are the patterns of dominance and rarity in tree...
Tropical forest succession increases tree taxonomic and functional richness but decreases evennessNARA Subscribed
Aim Successional changes in functional diversity provide insights into community assembly by indicating how species are filtered into local communities based on their traits. Here, we assess successional changes in taxonomic and functional richness, evenness and redundancy along gradients of climate, soil pH and forest cover. Location Neotropics. Time period Last 0–100 years. Major taxa studied Trees. Methods We used 22 forest...
Tree demographic strategies largely overlap across succession in Neotropical wet and dry forest communitiesNARA Subscribed
Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies—combinations of growth, mortality and recruitment rates—of the tree species in the community. However, our understanding of de...
Successional shifts in tree demographic strategies in wet and dry Neotropical forestsNARA Subscribed
Aim Tropical forest succession and associated changes in community composition are driven by species demographic rates, but how demographic strategies shift during succession remains unclear. Our goal was to identify generalities in demographic trade‐offs and successional shifts in demographic strategies across Neotropical forests that cover a large rainfall gradient and to test whether the current conceptual model of tropical...
Natural forest regrowth is a cost‐effective, nature‐based solution for biodiversity recovery, yet different socioenvironmental factors can lead to variable outcomes. A critical knowledge gap in forest restoration planning is how to predict where natural forest regrowth is likely to lead to high levels of biodiversity recovery, which is an indicator of conservation value and the potential provisioning of diverse ecosystem servi...
Seed‐rain–successional feedbacks in wet tropical forestsNARA Subscribed
Tropical forest regeneration after abandonment of former agricultural land depends critically on the input of tree seeds, yet seed dispersal is increasingly disrupted in contemporary human‐modified landscapes. Here, we introduce the concept of seed‐rain–successional feedbacks as a deterministic process in which seed rain is shaped by successional dynamics internal to a forest site and that acts to reinforce priority effects. W...
Evaluating the potential of full‐waveform lidar for mapping pan‐tropical tree species richnessNARA Subscribed
Aim Mapping tree species richness across the tropics is of great interest for effective conservation and biodiversity management. In this study, we evaluated the potential of full‐waveform lidar data for mapping tree species richness across the tropics by relating measurements of vertical canopy structure, as a proxy for the occupation of vertical niche space, to tree species richness. Location Tropics. Time period Present. Ma...
Successional dynamics of nitrogen fixation and forest growth in regenerating Costa Rican rainforestsNARA Subscribed
Regenerating tropical forests have an immense capacity to capture carbon and harbor biodiversity. The recuperation of the nitrogen cycle following disturbance can fuel biomass regeneration, but few studies have evaluated the successional dynamics of nitrogen and nitrogen inputs in tropical forests. We assessed symbiotic and asymbiotic nitrogen fixation, soil inorganic nitrogen concentrations, and tree growth in a well‐studied...
Aim Large tropical trees form the interface between ground and airborne observations, offering a unique opportunity to capture forest properties remotely and to investigate their variations on broad scales. However, despite rapid development of metrics to characterize the forest canopy from remotely sensed data, a gap remains between aerial and field inventories. To close this gap, we propose a new pan‐tropical model to predic...
Chronosequence predictions are robust in a Neotropical secondary forest, but plots miss the markNARA Subscribed
Tropical secondary forests (TSF) are a global carbon sink of 1.6 Pg C/year. However, TSF carbon uptake is estimated using chronosequence studies that assume differently aged forests can be used to predict change in aboveground biomass density (AGBD) over time. We tested this assumption using two airborne lidar datasets separated by 11.5 years over a Neotropical landscape. Using data from 1998, we predicted canopy height and AG...
Opposing mechanisms affect taxonomic convergence between tree assemblages during tropical forest successionNARA Subscribed
Whether successional forests converge towards an equilibrium in species composition remains an elusive question, hampered by high idiosyncrasy in successional dynamics. Based on long‐term tree monitoring in second‐growth ( SG ) and old‐growth ( OG ) forests in Costa Rica, we show that patterns of convergence between pairs of forest stands depend upon the relative abundance of species exhibiting distinct responses to the succes...
Deciphering the enigma of undetected species, phylogenetic, and functional diversity based on Good‐Turing theoryNARA Subscribed
Estimating the species, phylogenetic, and functional diversity of a community is challenging because rare species are often undetected, even with intensive sampling. The Good‐Turing frequency formula, originally developed for cryptography, estimates in an ecological context the true frequencies of rare species in a single assemblage based on an incomplete sample of individuals. Until now, this formula has never been used to es...
Unveiling the species‐rank abundance distribution by generalizing the Good‐Turing sample coverage theoryNARA Subscribed
Based on a sample of individuals, we focus on inferring the vector of species relative abundance of an entire assemblage and propose a novel estimator of the complete species‐rank abundance distribution (RAD). Nearly all previous estimators of the RAD use the conventional “plug‐in” estimator p̂ i (sample relative abundance) of the true relative abundance p i of species i . Because most biodiversity samples are incomplete, the...
Decomposing biodiversity data using the Latent Dirichlet Allocation model, a probabilistic multivariate statistical methodNARA Subscribed
We propose a novel multivariate method to analyse biodiversity data based on the Latent Dirichlet Allocation ( LDA ) model. LDA , a probabilistic model, reduces assemblages to sets of distinct component communities. It produces easily interpretable results, can represent abrupt and gradual changes in composition, accommodates missing data and allows for coherent estimates of uncertainty. We illustrate our method using tree dat...