Jos Barlow’s research while affiliated with Lancaster University and other places

Natural regeneration of Amazon forests offers a promising strategy to mitigate forest loss and advance the goals of the UN Decade on Ecosystem Restoration. However, the vast variability in regeneration rates across environmental gradients and over time poses considerable challenges for assessing regeneration success and ecosystem services provision in human-modified landscapes. Here we compiled 448 plots from forest regeneration in the Amazon to investigate the drivers of regrowth capacity and identify robust ecological indicators. By modeling optimal successional trajectories, we estimated reference values for vegetation structure, diversity, and functioning. After 20 years, successful regeneration should reach a minimum basal area of 14 m². ha⁻¹, at least 34 tree species per 100 individuals, a structural heterogeneity index of 0.27, and 123 Mg.ha⁻¹ of aboveground biomass. These straightforward indicators and reference values provide a foundational framework for governments and practitioners to assess success and establish targets for Amazon restoration efforts.

Soil ecoacoustics is a rapidly emerging field heralded as a non-invasive method for monitoring soil fauna. Ecoacoustic analysis commonly uses acoustic indices to analyse soundscapes, linking them to 'traditional' biodiversity value metrics such as species richness and abundance, but it is not clear if this approach is appropriate for soil soundscapes. Furthermore, there are very few controlled experiments assessing how commonly used acoustic indices respond to different sound types, and none belowground. We address this by synthesising soil soundscapes with differing levels of acoustic richness, abundance, and evenness using soil recordings from the UK, France, and Brazil. Applying 14 acoustic indices on 1-minute soundscapes, we assessed: 1) how changes in acoustic diversity impact acoustic indices and 2) how accurately combinations of indices predict biodiversity metrics. Finally we assessed 3) whether gamma acoustic richness can be predicted accurately using multiple acoustic index scores from repeated surveys, whilst experimentally altering the alpha and beta diversity components. We find that acoustic abundance strongly affects values of acoustic indices designed to quantify the number of sound events in a soundscape, and that a combination of these indices can accurately predict abundance at 1-minute timescales. Combinations of indices could predict acoustic richness when richness values were low, but were ineffective for evenness. Additionally, acoustic indices were poor predictors of gamma diversity, especially when gamma was driven solely by beta diversity. Overall, we found that acoustic indices were good predictors of acoustic abundance, but should be used with caution for other diversity metrics.

Anthropogenic landscape modification may lead to the proliferation of a few species and the loss of many. Here we investigate mechanisms and functional consequences of this winner–loser replacement in six human-modified Amazonian and Atlantic Forest regions in Brazil using a causal inference framework. Combining floristic and functional trait data for 1,207 tree species across 271 forest plots, we find that forest loss consistently caused an increased dominance of low-density woods and small seeds dispersed by endozoochory (winner traits) and the loss of distinctive traits, such as extremely dense woods and large seeds dispersed by synzoochory (loser traits). Effects on leaf traits and maximum tree height were rare or inconsistent. The independent causal effects of landscape configuration were rare, but local degradation remained important in multivariate trait-disturbance relationships and exceeded the effects of forest loss in one Amazonian region. Our findings highlight that tropical forest loss and local degradation drive predictable functional changes to remaining tree assemblages and that certain traits are consistently associated with winners and losers across different regional contexts.

Journal of Applied Ecology celebrates its 60th birthday in 2024. In this Editorial, we explore how the journal's role has changed since its launch and investigate whether the articles we publish are achieving real‐world impact. We designed and ran an author survey for all authors who have published with us between 2017 and 2021. Authors were asked if their publication achieved real‐world impact, and if so, how they achieved it. Forty four percent of respondents achieved real‐world impact with their article, primarily citing engagement with key stakeholders as the reason for this impact. We also assessed our impact on online policy documentation, comparing this to our citations in the published scientific literature. We are the most highly cited British Ecological Society journal for policy mentions with over 2800 citations in total. We also found a weak correlation between policy citations and citations in academic literature, which highlights the fact that article with relatively few academic citations can have large real‐world impact. Synthesis and applications. Whilst these results are encouraging, there are significant challenges involved in achieving and measuring impact scale. To help address some of these, we launch here a suite of new author services to help our authors achieve real‐world impact with their work. This includes offering plain language summaries and the opportunity to present findings to British Ecological Society's stakeholder community.

Leaf and wood functional traits of trees are related to growth, reproduction, and survival, but the degree of phylogenetic conservatism in these relationships is largely unknown. In this study, we describe the variability of strategies involving leaf, wood and demographic characteristics for tree genera distributed across the Amazon Region, and quantify phylogenetic signal for the characteristics and their relationships. Leaf and wood traits are aligned with demographic variables along two main axes of variation. The first axis represents the coordination of leaf traits describing resource uptake and use, wood density, seed mass, and survival. The second axis represents the coordination between size and growth. Both axes show strong phylogenetic signal, suggesting a constrained evolution influenced by ancestral values, yet the second axis also has an additional, substantial portion of its variation that is driven by functional correlations unrelated to phylogeny, suggesting simultaneously higher evolutionary lability and coordination. Synthesis. Our results suggest that life history strategies of tropical trees are generally phylogenetically conserved, but that tree lineages may have some capability of responding to environmental changes by modulating their growth and size. Overall, we provide the largest‐scale synopsis of functional characteristics of Amazonian trees, showing substantial nuance in the evolutionary patterns of individual characteristics and their relationships. Read the free Plain Language Summary for this article on the Journal blog.

The Kunming-Montreal Global Biodiversity Framework marked a renewed commitment to address the biodiversity crisis. This framework, consisting of four goals and 23 targets which are intended to guide conservation efforts for the next thirty years, displays an enhanced level of ambition compared to its predecessor. However, the pursuit of multilateral agreements is dependent upon national pledges, and national pledges are of little worth without subsequent sub-national action. We assess the currently submitted National Biodiversity Strategy and Action Plans of member countries to determine the extent to which they align with the bold ambition of the GBF. We find a lack of consistency between the GBF and country submissions across many targets, with the notable exception being target 3 – to increase protected area coverage to 30% by 2030. Reflecting on the current submissions, we draw on recent developments and our own experience to outline key considerations that could help guide GBF implementation efforts. We caution against cherry-picking of specific targets to suit political-economic agendas, highlight that an overemphasis on Target 3 alone will not lead to the desired state of living in harmony with nature, and that to do so actually requires a more holistic and inclusive approach to conservation.

Wildfires associated with land-use and climate change have considered a key driver to the Amazon forest collapse. However, achieving a detailed understanding of how human-related disturbances impact forest successional trajectories needs comprehensive information spanning forest strata. Here, we investigate the impact of recurrent wildfires on forest structure, species diversity, and composition, making a comprehensive assessment of the regenerating, understory, and canopy tree communities in a sustainable use reserve in the eastern Amazon. Plant communities were described across 16 forest stands (old-growth, burned once and twice) sampling a total of 3620 individuals and 326 tree and palm species. Wildfires affected all attributes of forest structure. Aboveground biomass decreased by 44% in forest burned once, and 71% in twice-burned forest stands. Forest canopy was the most affected strata after the second fire, with a 44%-decrease compared to unburned forest. The same pattern emerged for basal area, which decreased by an average of 27.5% after the first fire and 53.8% following the second fire event. Overall, plant communities experienced a 50%-loss of species richness after two fires, including both dominant and rare species. Plant communities also became more dissimilar as fire events accumulated, with 58%–61% increase in species dissimilarity following two fires events. As wildfires reoccured, the old-growth forests of our focal landscape were converted into a mosaic of regenerating forest stands dominated by local short-lived pioneers (i.e. low-biomass early-regenerating forest stands) and a few tree species less sensitive to fire. Our findings highlight the urgent need to secure a resilient future for Amazonian forests with actions needed to support local livelihoods whilst reducing the prevalence of ignitions sources and allowing forest recovery.

We describe the geographical variation in tree species composition across Amazonian forests and show how environmental conditions are associated with species turnover. Our analyses are based on 2023 forest inventory plots (1 ha) that provide abundance data for a total of 5188 tree species. Within-plot species composition reflected both local environmental conditions (especially soil nutrients and hydrology) and geographical regions. A broader-scale view of species turnover was obtained by interpolating the relative tree species abundances over Amazonia into 47,441 0.1-degree grid cells. Two main dimensions of spatial change in tree species composition were identified. The first was a gradient between western Amazonia at the Andean forelands (with young geology and relatively nutrient-rich soils) and central–eastern Amazonia associated with the Guiana and Brazilian Shields (with more ancient geology and poor soils). The second gradient was between the wet forests of the northwest and the drier forests in southern Amazonia. Isolines linking cells of similar composition crossed major Amazonian rivers, suggesting that tree species distributions are not limited by rivers. Even though some areas of relatively sharp species turnover were identified, mostly the tree species composition changed gradually over large extents, which does not support delimiting clear discrete biogeographic regions within Amazonia.

Much research and media attention has revolved around the environmental impacts of growing global human populations. While the conclusions remain contested, these assessments have largely neglected the ecological and conservation impacts of other key regional processes such as declining populations, ageing demographics and rural‐to‐urban migration. These demographic shifts are increasingly prevalent across many regions of the world, and will have significant direct effects on natural resource management and biodiversity conservation by altering individual consumption patterns, land use, land stewardship and natural disturbances. Given that the scientific foundation around this topic is still developing, we first present an initial examination of some of the key environmental impacts, aiming to elevate awareness and encourage further research in these areas. Beyond the ecological implications, declining populations, ageing demographics and rural‐to‐urban migration carry intricate social and cultural consequences that can affect people and nature interactions. Ecological studies that focus on single dimensions of biodiversity or ecosystem responses often overlook these complexities. Demographic changes are likely to be accompanied by shifts in environmental attitudes and connections with nature, all of which will influence our capacity to adapt to or mitigate environmental changes. Finally, environmental policy and practice frameworks are potentially unprepared and their success could be sensitive to these socio‐cultural and demographic shifts. Synthesis and applications: This brief overview demonstrates that population decline, ageing and rural‐to‐urban migration can have extensive implications for biodiversity and the socio‐cultural relationships between people and nature. However, the significance, dynamics and consequences of these processes are still largely overlooked. We believe that these changes warrant specific attention from the research, policy and practice communities, as understanding the outcomes and feedbacks associated with depopulation, ageing populations, loss of culture and tradition and ecological change could aid in designing landscapes and informing management that enhances both human well‐being and biodiversity conservation.