Ecology最新文献

A major challenge in invasion ecology is determining which introduced species pose a threat to resident species through competitive displacement. Since it is impossible to allocate management resources to preventing interactions among all resident and introduced species, methods for identifying instances of potential competitive displacement would greatly help focus precious management resources. Additionally, methods that use readily available data, such as species counts or functional traits, are especially advantageous under urgent invasion timelines compared to those requiring more time-intensive experimental data. Here, we provide a framework for estimating competition outcomes—including displacement—between resident and invading species using species count and functional trait data, two readily available data sources. Our framework provides methods for estimating displacement that is possibly in progress from species count data and estimating possible displacement from functional traits. We apply this framework to the native and introduced gecko species on the Caribbean island of Curaçao. Our work indicates a potential for the displacement of all three native species by introduced species and suggests that the displacement of one native species may already be underway. Given the urgency of the biodiversity crisis, our framework provides a usable tool for the early identification of potentially detrimental interactions from introduced species and provides insights to focus future studies and guide management efforts.

Living shorelines, a prevalent nature-based coastal infrastructure technique, typically merge the restoration of coastal habitats (e.g., salt marsh, oyster reef) with gray infrastructure (e.g., rock or concrete breakwaters) to provide coastal erosion protection. With increasingly frequent and severe storms, living shorelines have been shown to effectively limit coastal erosion and loss; however, there is still uncertainty regarding the effects of living shorelines on nekton communities as compared to natural marshes and gray coastal protection strategies like bulkheads. Here, we present a dataset of living shoreline-associated nekton species recorded over a 20-year period in North Carolina, USA. We harmonized nekton abundance and biomass data from five different studies (each ranging in duration from 2 to 4 years) across 12 living shorelines with paired natural marshes and, in some cases, bulkheads. These studies used different gear types and sampling methodologies, and therefore future users of this dataset must carefully consider the limitations of different subsets of the data and ensure that they do not make direct catch comparisons across sites that used different methodologies. Altogether, we identified a total of 62 species groups at living shorelines, natural reference marshes, and bulkheads across three categories (i.e., crustacean, mollusk, and fish) between 2001 and 2024. We identified 49 species groups on living shorelines, 49 species groups in natural marshes, and 5 species groups on bulkheads. For each living shoreline and paired natural marsh and/or bulkhead shoreline, we report individual species counts, biomass (when available), and the sampling method. In addition, we report on the living shoreline type, age, and location. In total, these data provide vital insight into how living shorelines function as habitat for nekton, and they can be used to evaluate living shoreline effectiveness as a predominant nature-based solution for coastal protection and biodiversity enhancement. The data are released under the Creative Commons Attribution 4.0 International License.

Plant functional group is increasingly recognized as vital for supporting multiple ecosystem functions simultaneously. However, variations in “ecosystem multifunctionality” relative to plant functional groups remain unclear, particularly in Antarctic terrestrial ecosystems. In particular, how plant presence relates to multifunctionality, whether this directly relates to their carbon inputs, or indirectly, via local changes in abiotic (soil moisture and pH), and biotic (soil biodiversity and their interactions) factors, is still an unresolved question. In this study, we collected soil samples from five areas in the Antarctic region, ranging from bare soil to areas dominated by nonvascular plants such as lichens, mosses, and vascular plants. We examined 12 ecosystem functions associated with carbon sequestration, nitrogen stock and cycling, soil organic matter (SOM) decomposition, microbial biomass and pathogen control to calculate ecosystem multifunctionality. Our results showed that ecosystem multifunctionality was higher in areas colonized by nonvascular plants and vascular plants compared to bare soil, which was concurrent with enhanced levels of carbon sequestration, SOM decomposition, and microbial biomass. Our structural equation model (SEM) showed that increased ecosystem multifunctionality beneath plants was associated with a higher number of microbial module hubs (indicative of stronger interdependence among microbial taxa) in nonvascular plants, but not in vascular plants. Analysis of SEM standardized contributions revealed the direct pathway as predominant in the connectivity pattern between vascular plant presence and ecosystem multifunctionality. Overall, these findings enhance our understanding of the differences in the pathways linking nonvascular plants, vascular plants, and ecosystem multifunctionality. It further highlights the necessity of incorporating microbial interactions to more effectively evaluate ecosystem multifunctionality, particularly in the context of Antarctic ecosystems.

Climate change has substantially shifted the phenology of many organisms. These shifts vary across species and habitats and are shaped by species' natural history traits and local environmental conditions, yet the relative importance of these drivers remains unclear. Moreover, climate can have diverse effects on different aspects of phenology, such as the timing and duration of activity, but this complexity is rarely captured by commonly used phenological metrics. We used multidecadal butterfly surveys and climate data from five montane sites spanning an elevational gradient to investigate how climate affects different aspects of the annual flight period of 135 butterfly species. Using a hierarchical Bayesian framework, we modeled annual probability of occurrence distributions for species using polynomial models that capture changes in abundance, timing, and length of flight. Spring maximum and minimum temperatures and winter precipitation were the best predictors of interannual variation in phenology. High winter precipitation, which usually comes in the form of snow, delayed phenology, while warmer spring maximum temperatures advanced phenology across elevations. Even modest increases in spring minimum (nighttime) temperatures caused strong phenological shifts. Climate effects varied among sites, among species within sites, and even among populations of the same species across sites, with particularly pronounced variation among species at a single location. Variation in climate effects was slightly better explained by local climate than by natural history traits. Among natural history traits, voltinism and overwintering stage were particularly influential. Importantly, climate influenced different aspects of the flight period (e.g., timing versus duration) in distinct ways, with both natural history traits and local climate modulating these responses. Our findings highlight the often-overlooked importance of winter precipitation and nighttime temperatures in shaping phenology and demonstrate the value of considering the entire flight period, rather than distinct aspects alone, to improve our understanding and predictions of species response to climate change.

Quantitative evidence synthesis is a prominent path towards generality in ecology. Generality is typically discussed in terms of central tendencies, such as an average effect across a compilation of studies, and the role of heterogeneity for assessing generality is less well developed. Heterogeneity examines the transferability of ecological effects across contexts, though between-study variance is typically assumed as constant (i.e., homoscedastic). Here, I use two case studies to show how location-scale models that relax the assumption of homoscedasticity and cross validation can combine to further the goals of evidence syntheses. First, I examine scale-dependent heterogeneity for a meta-analysis of plant native-exotic species richness relationships, quantifying the relationships among unexplained effect size variation, spatial grain and extent. Second, I examine relationships among habitat fragment size, study-level covariates and unexplained variation in patch-scale species richness using a database of fragmentation studies. Heteroscedastic models quantify where effects can be transferred with more or less certainty and provide new descriptions of transferability for both case studies. Cross validation can be applied to a single or multiple models, adapted to either the goal of assessing intervention efficacy or generalization and, for the case studies examined here, showed that assuming homoscedasticity limits transferability.

Portfolio mechanisms are widely recognized as essential processes through which biodiversity promotes ecosystem stability. However, traditional theories often treat biodiversity as a static property, overlooking its dynamic nature, which is shaped by numerous ecosystem-level processes identified since the 1950s. To address this gap, we develop a novel model framework grounded in island biogeography theory (IBT) to explore the ecosystem-level mechanisms by which biodiversity and its dynamics influence ecosystem stability. This framework considers species diversity as a state variable, capturing its dynamical behavior driven by feedback mechanisms between species diversity, resource availability (nutrients), and the effects of diversity on multitrophic interactions within a plankton system. Specifically, our model demonstrates that phytoplankton diversity regulates the strength of plankton trophic interactions, which in turn alter plankton biomass and nutrient availability. These changes generate feedback loops that further reshape phytoplankton diversity itself. The presence of the feedback loops enhances the system's resistance to extinction: Increasing diversity promotes more efficient resource consumption when consumers face extinction risk, while declining diversity reduces resource consumption efficiency, thereby mitigating destabilization caused by consumer overgrazing. The critical role of species diversity dynamics in ecosystem stability is empirically supported by our analysis of a 30-year phytoplankton dataset, which reveals a causal relationship between temporal variability in phytoplankton species richness and the stability of community biomass. Our findings unveil a new mechanism through which biodiversity influences ecosystem stability via ecosystem-level processes, independently of population- or community-level portfolio processes.

In an era of change, the survival and adaptability of ecosystems will be tested. An optimal ecosystem would be both resistant and resilient to negative disturbance but also efficient and redundant in its growth when given positive subsidies. However, initial evidence has suggested that these properties cannot all be maximized at the same time, and so we sought to quantitatively assess whether there are fundamental trade-offs between them at the ecosystem level. To achieve this aim, we used a 250-m resolution NASA MODIS dataset of gross primary productivity (GPP) to monitor 145,871 tidal wetland locations across the conterminous United States every 16 days from March 2000 to December 2020. We quantified the size and duration of the perturbation events in tidal wetland GPP (n = 13,754,386) and modeled their frequency distributions. Event sizes and recurrence intervals were exponentially distributed and event durations were closely modeled by an inverse power law. This scale-free manner through which tidal wetlands dissipated perturbations to their GPP flux provided them with long-term stability across a wide range of geography. We also found that a tidal wetland's positive event responses traded off between properties of efficiency and redundancy, its negative events traded off between resistance and resilience, and that all four properties were orthogonally related to one another. We then constructed a conceptual model to help understand the potential mechanism behind this four-quadrant trade-off. The trade-off appeared to be driven by a feedback between the waiting time and magnitude of positive and negative events, the duration of their effects, and the environmental and physical constraints limiting an ecosystem's growth and productivity. In summary, we detail an emergent pattern of trade-offs and constraints associated with how tidal wetland ecosystems respond to both positive and negative perturbations in carbon flux.

Mutualisms are complex, interspecific relationships, which sometimes create “selfish-herds” as individuals of each species compete to maximize their own fitness. Nest association, where individuals of different species spawn on a nest created by a host species, is a reproductive interaction characteristic of some minnows (Leuciscidae) and is considered mutualistic despite mimicking the behavior labeled “brood parasitism.” We studied the spawning behaviors of bluehead chub (Nocomis leptocephalus) and its nest associates, testing the hypothesis that bluehead chub exploits the selfish-herd dynamic in a novel manner by arranging embryos within its nest to maximize the survival of its own offspring at the expense of the nest associates' offspring. Our results show that embryos were not uniformly distributed within a nest, as one section representing one-sixth of the nest's total volume contained a disproportionate percentage of embryos (x¯ = 40.0% ± 6.1% SE). We found three-quarters of host embryos within deeper nest sections safer from embryo predators, whereas only a third of all associate embryos were found in the same sections. These results support our hypothesis that male Nocomis leptocephalus create “embryonic selfish-herds” within their nests. This is the first study to document the existence of embryonic selfish-herds, a phenomenon that warrants the reexamination of some vertebrate reproductive interactions labeled as brood parasitism.