Ecology Letters最新文献

Modelling the dynamics of biological processes is ubiquitous across the ecological and evolutionary disciplines. However, the increasing complexity of these models poses a challenge to the dissemination of model-derived results. Often only a small subset of model results are made available to the scientific community, with further exploration of the parameter space relying on local deployment of code supplied by the authors. This can be technically challenging, owing to the diversity of frameworks and environments in which models are developed. To address this issue, we developed a platform that serves as an interactive repository of biological models, called modelRxiv. To facilitate adding models to modelRxiv, we utilise large-language models (LLMs) to make the platform language-agnostic. The platform provides a unified interface for the analysis of models that do not require any technical understanding of the model implementation, thus improving the accessibility, reproducibility and validation of ecological and evolutionary models.

Microorganisms underpin numerous ecosystem processes and support biodiversity globally. Yet, we understand surprisingly little about what structures environmental microbiomes, including how to efficiently identify key players. Microbiome network theory predicts that highly connected hubs act as keystones, but this has never been empirically tested in nature. Combining culturing, sequencing, networks and field experiments, we isolated ‘central’ (highly connected, hub taxa), ‘intermediate’ (moderately connected), and ‘peripheral’ (weakly/unconnected) microbes and experimentally evaluated their effects on soil microbiome assembly during early succession in nature. Central early colonisers significantly (1) enhanced biodiversity (35%–40% richer communities), (2) reshaped trajectories of microbiome assembly and (3) increased recruitment of additional influential microbes by > 60%. In contrast, peripheral microbes did not increase diversity and were transient taxa, minimally affected by the presence of other microbes. This work elucidates fundamental principles of network theory in microbial ecology and demonstrates for the first time in nature that central microbes act as keystone taxa.

Trait-based approaches have been increasingly used to relate plants to soil microbial communities. Using the recently described root economics space as an approach to explain the structure of soil-borne fungal communities, our study in a grassland diversity experiment reveals distinct root trait strategies at the plant community level. In addition to significant effects of plant species richness, we show that the collaboration and conservation gradient are strong drivers of the composition of the different guilds of soil fungi. Saprotrophic fungi are most diverse in species-rich plant communities with ‘slow’ root traits, whereas plant pathogenic fungi are most diverse and abundant in communities with ‘fast’ and ‘DIY’ root traits. Fungal biomass is strongly driven by plant species richness. Our results illustrate that the root economics space and plant species richness jointly determine the effects of plants on soil fungal communities and their potential role in plant fitness and ecosystem functioning.

Empirical studies worldwide show that warming has variable effects on plant litter decomposition, leaving the overall impact of climate change on decomposition uncertain. We conducted a meta-analysis of 109 experimental warming studies across seven continents, using natural and standardised plant material, to assess the overarching effect of warming on litter decomposition and identify potential moderating factors. We determined that at least 5.2° of warming is required for a significant increase in decomposition. Overall, warming did not have a significant effect on decomposition at a global scale. However, we found that warming reduced decomposition in warmer, low-moisture areas, while it slightly increased decomposition in colder regions, although this increase was not significant. This is particularly relevant given the past decade's global warming trend at higher latitudes where a large proportion of terrestrial carbon is stored. Future changes in vegetation towards plants with lower litter quality, which we show were likely to be more sensitive to warming, could increase carbon release and reduce the amount of organic matter building up in the soil. Our findings highlight how the interplay between warming, environmental conditions, and litter characteristics improves predictions of warming's impact on ecosystem processes, emphasising the importance of considering context-specific factors.

The daily transition between day and night, known as the diel cycle, is characterised by significant shifts in environmental conditions and biological activity, both of which can affect crucial ecosystem functions like pollination. Despite over six decades of research into whether pollination varies between day and night, consensus remains elusive. We compiled the evidence of diel pollination from 135 studies with pollinator exclusion experiments involving 139 angiosperms. We used phylogenetic multi-level meta-analysis to test the influence of environmental conditions and plant functional traits on diel pollination differences. Our synthesis revealed an overall lack of difference in pollination between day and night; many plant species (90% of studied spp.) exhibit similar pollination success across the diel cycle. Diel pollination differences were partially explained by elevation: nocturnal pollination success was greater at low elevations, whereas diurnal pollination was more beneficial at higher elevations. Furthermore, floral traits related to pollinator attraction (odour, colour) and anthesis time influenced diel pollination differences. In the light of increasing anthropogenic pressures on biodiversity, as well as unique challenges for nocturnal biota, this synthesis underscores the diel complementarity of pollinators for many flowering plants and the importance of considering both nocturnal and diurnal pollinators in agricultural and conservation contexts.

Whether large-scale variation in lineage diversification rates can be predicted by species properties at the population level is a key unresolved question at the interface between micro- and macroevolution. All else being equal, species with biological attributes that confer metapopulation stability should persist more often at timescales relevant to speciation and so give rise to new (incipient) forms that share these biological traits. Here, we develop a framework for testing the relationship between metapopulation properties related to persistence and phylogenetic speciation rates. We illustrate this conceptual approach by applying it to a long-term dataset on demersal fish communities from the North American continental shelf region. We find that one index of metapopulation persistence has phylogenetic signal, suggesting that traits are connected with range-wide demographic patterns. However, there is no relationship between demographic properties and speciation rate. These findings suggest a decoupling between ecological dynamics at decadal timescales and million-year clade dynamics, raising questions about the extent to which population-level processes observable over ecological timescales can be extrapolated to infer biodiversity dynamics more generally.

The Kenya long-term exclosure experiment (KLEE) was established in 1995 in semi-arid savanna rangeland to examine the separate and combined effects of livestock, wildlife and megaherbivores on their shared environment. The long-term nature of this experiment has allowed us to measure these effects and address questions of stability and resilience in the context of multiple drought-rainy cycles. Here we outline lessons learned over the last 29 years, and how these inform a fundamental tension in long-term studies: how to balance the need for question-driven research with the intangible conviction that long-term data will yield valuable findings. We highlight the value of (1) identifying experimental effects that take many years to manifest, (2) quantifying the effects of different years (including droughts) and (3) capturing the signatures of anthropogenic change. We also highlight the potential for long-term studies to create a collaborative community of scientists that brings new questions and motivates continued long-term study.

Insect declines are raising alarms regarding cascading effects on ecosystems, especially as many insectivorous bird populations are also declining. Here, we leveraged long-term monitoring datasets across Finland to investigate trophic dynamics between functional groups of moths and birds in forested habitats. We reveal a positive association between the biomass of adult- or egg-overwintering moths and the biomasses of resident and long-distance migrant birds reliant on caterpillars as breeding-season food in the north-boreal zone. Contrary to expectations, similar signs of moth bottom-up effects on insectivorous birds were not observed in other Finnish regions or for moths overwintering in other life stages. In fact, some negative associations between moths and birds were even detected, possibly attributable to opposite abundance trends. While supporting the existence of bottom-up effects in the north-boreal zone, our study emphasizes the need for further investigation to elucidate moth-mediated trophic dynamics in areas characterized by the insect decline.