Vegetation Patterning Can Both Impede and Trigger Critical Transitions from Savanna to Grassland
Fuente:
arXiv
Enregistré dans:
| Auteurs principaux: | , , , , |
|---|---|
| Format: | Preprint |
| Publié: |
2025
|
| Sujets: | |
| Accès en ligne: | |
| Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|
| _version_ | 1866915943930658816 |
|---|---|
| author | van der Voort, Jelle Baudena, Mara Meron, Ehud Rietkerk, Max Doelman, Arjen |
| author_facet | van der Voort, Jelle Baudena, Mara Meron, Ehud Rietkerk, Max Doelman, Arjen |
| contents | Tree-grass coexistence is a defining feature of savanna ecosystems, which play an important role in supporting biodiversity and human populations worldwide. While recent advances have clarified many of the underlying processes, how these mechanisms interact to shape ecosystem dynamics under environmental stress is not yet understood. Here, we present and analyze a minimalistic spatially extended model of tree-grass dynamics in dry savannas. We incorporate tree facilitation of grasses through shading and grass competing with trees for water, both varying with tree life stage. Our model shows that these mechanisms lead to grass-tree coexistence and bistability between savanna and grassland states. Moreover, the model predicts vegetation patterns consisting of trees and grasses, particularly under harsh environmental conditions, which can persist in situations where a non-spatial version of the model predicts ecosystem collapse from savanna to grassland instead (a phenomenon called ``Turing-evades-tipping''). Additionally, we identify a novel ``Turing-triggers-tipping'' mechanism, where unstable pattern formation drives tipping events that are overlooked when spatial dynamics are not included. These transient patterns act as early warning signals for ecosystem transitions, offering a critical window for intervention. Further theoretical and empirical research is needed to determine when spatial patterns prevent tipping or drive collapse. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2506_22178 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Vegetation Patterning Can Both Impede and Trigger Critical Transitions from Savanna to Grassland van der Voort, Jelle Baudena, Mara Meron, Ehud Rietkerk, Max Doelman, Arjen Populations and Evolution Analysis of PDEs Dynamical Systems Pattern Formation and Solitons Biological Physics Tree-grass coexistence is a defining feature of savanna ecosystems, which play an important role in supporting biodiversity and human populations worldwide. While recent advances have clarified many of the underlying processes, how these mechanisms interact to shape ecosystem dynamics under environmental stress is not yet understood. Here, we present and analyze a minimalistic spatially extended model of tree-grass dynamics in dry savannas. We incorporate tree facilitation of grasses through shading and grass competing with trees for water, both varying with tree life stage. Our model shows that these mechanisms lead to grass-tree coexistence and bistability between savanna and grassland states. Moreover, the model predicts vegetation patterns consisting of trees and grasses, particularly under harsh environmental conditions, which can persist in situations where a non-spatial version of the model predicts ecosystem collapse from savanna to grassland instead (a phenomenon called ``Turing-evades-tipping''). Additionally, we identify a novel ``Turing-triggers-tipping'' mechanism, where unstable pattern formation drives tipping events that are overlooked when spatial dynamics are not included. These transient patterns act as early warning signals for ecosystem transitions, offering a critical window for intervention. Further theoretical and empirical research is needed to determine when spatial patterns prevent tipping or drive collapse. |
| title | Vegetation Patterning Can Both Impede and Trigger Critical Transitions from Savanna to Grassland |
| topic | Populations and Evolution Analysis of PDEs Dynamical Systems Pattern Formation and Solitons Biological Physics |
| url | https://arxiv.org/abs/2506.22178 |