Biology subjects

Khelidj, N.

Publications and source records attributed to Khelidj, N..

4 recordsLinked to original sources

bioRxiv2026

Glacier retreat reshapes trophic networks: interaction turnover outpaces species turnover over space-time

As glaciers retreat worldwide, newly exposed terrains are rapidly colonized by plants and their associated animal communities. Although plant-animal interactions are key for biodiversity maintenance and ecosystem functioning, the ecological processes underlying the assembly and development of trophic interactions over space-time remain poorly understood. Here, we investigated the trophic niche structure of plant-arthropod interactions along a 140-year primary succession at Mont Mine glacier foreland (Switzerland). Using arthropod gut-content DNA metabarcoding, we reconstructed trophic interactions at the food web level, revealing numerous previously undetected links among 284 arthropod taxa feeding on 263 plant taxa. Trophic niche overlap among arthropods increased following glacier retreat, indicating decreasing resource partitioning and suggesting increased resource competition. Trophic niche breadth became narrower and diet species richness declined, indicating increased trophic specialization. Notably, changes in trophic interactions occurred more rapidly than shifts in species diversity or community composition of plants and arthropods. These results demonstrate that glacier retreat reorganizes trophic networks beyond simple species turnover, reshaping biotic interactions during ecosystem development. Our findings highlight trophic interactions as sensitive indicators of biodiversity change and suggest that the stability of emerging food webs may be strongly affected as glaciers vanish worldwide.

ecology↗

bioRxiv2025

Ecological indicators predict functional diversity dynamics following glacier retreat

The retreat of glaciers due to climate change is reshaping mountain landscapes and biodiversity. While previous research has documented vegetation succession after glacier retreat, our understanding of functional diversity dynamics is still limited. In this case study, we address the effects of glacier retreat on plant functional diversity by integrating plant traits with ecological indicator values across a 140-year chronosequence in a subalpine glacier landscape. We reveal that functional richness and functional dispersion decrease with glacier retreat, while functional evenness and functional divergence increase, suggesting a shift towards more specialized and competitive communities. Our findings highlight the critical role of ecological factors related to soil moisture, soil nutrients, and light availability in shaping plant community dynamics. The integrative approach of this case study provides novel insights into the potential response of alpine plant communities to climate change, offering a deeper understanding of how to predict and anticipate the effects of glacier extinction on biodiversity in rapidly changing environments.

ecology↗

bioRxiv2023

Glacier extinction homogenizes functional diversity

QuestionsThe disappearance of glaciers threatens biodiversity and the functioning of ecosystems. To date, questions remain about the response of functional diversity to glacier extinction and its potential for adaptation to climate change. How does glacier retreat and extinction affect plant functional diversity? How do mean and variation of plant traits change with glacier retreat and extinction? LocationFour glacier ecosystems in Italian Alps. Plant communities spanning 0 to ca 5,000 years on average after glacier retreat. MethodsWe quantify how glacier retreat affects functional diversity of plant communities analysing twelve functional traits of 117 plant species across 170 plots. First, we addressed the impact of glacier retreat on functional divergence and functional homogeneity, analysing both trait average and trait variation. Next, we explored how biodiversity (i.e., plant species richness) influenced functional diversity and how glacier retreat affected such relationship. Finally, we explored the effects of glacier retreat on mean and variation of single traits associated to carbon and nitrogen cycling and resource allocation. ResultsGlacier retreat homogenizes functional diversity by reducing trait variation and making communities more functionally similar. While biodiversity positively contributes to trait heterogeneity, glacier retreat erodes the support of species richness to functional diversity. We also show how glacier extinction has medium to large negative effects on the average and variation of key functional traits associated to carbon economy, but small positive effects on leaf nitrogen content. ConclusionsOur results demonstrate the pervasive impact of glacier extinction on the functioning of plant communities. We stress that functional diversity and trait variation should be the focus of adaptation and mitigation actions.

ecology↗

bioRxiv2023

Impact of glacier retreat on biodiversity and plant-insect interaction dynamics

With the retreat and extinction of glaciers worldwide, new areas are exposed for colonization by diverse plants and associated insects. Yet, glacier retreat is also followed by the loss of plants and insects from local communities, causing changes in species diversity, species composition and plant-insect interactions. However, the impact of glacier retreat and extinction on pollination networks remains poorly understood. An integrative understanding of pollination network dynamics following glacier retreat is therefore of major importance to biodiversity maintenance and ecosystem functioning and services. Here, we addressed how glacier retreat affects directly and indirectly through biodiversity the frequency, complexity, and diversity of plant-insect interactions. After reconstructing the geochronology of glaciers (Mont Mine glacier, Swiss Alps), we surveyed plant-insect interactions and analyzed network dynamics. We observed sharp changes in the diversity of both plant and insect communities. We found an increase in the frequency of their interactions following glacier retreat, but an ultimate decrease with glacier extinction. Yet, after controlling for the effects of flower diversity, interaction frequency showed a regular, universal pattern. Accordingly, the complexity of pollination networks and interaction diversity tended to change at constant rates with glacier retreat. Our results indicate that, in the long-term, glacier retreat decreases biodiversity and influence the stability of ecological networks. The good news is that increasing flower diversity would counteract these impacts by increasing interaction diversity and complexity. Supporting plant and flower diversity may therefore be a key strategy for halting the erosion of ecological networks while increasing ecosystem functioning.

ecology↗