From scale-dependent feedbacks to long-range competition alone: a short review on pattern-forming mechanisms in arid ecosystems

TL;DR

This review discusses how scale-dependent feedbacks and interactions between facilitation and competition drive vegetation pattern formation in arid ecosystems, highlighting modeling approaches and similarities with other systems.

Contribution

It provides a comprehensive overview of biological processes and mathematical models explaining vegetation patterns, emphasizing the role of scale-dependent feedbacks.

Findings

Facilitative interactions dominate at short distances.

Competitive interactions dominate at larger scales.

Similar pattern structures are found in other biological and physical systems.

Abstract

Vegetation patterns are abundant in arid and semiarid ecosystems, but how they form remains unclear. One of the most extended theories lies in the existence of scale-dependent feedbacks (SDF) in plant-to-plant and plant-water interactions. Short distances are dominated by facilitative interactions, whereas competitive interactions dominate at larger scales. These feedbacks shape spatially inhomogeneous distributions of water that ultimately drive the emergence of patterns of vegetation. Even though the presence of facilitative and competitive interactions is clear, they are often hard to disentangle in the field, and therefore their relevance in vegetation pattern formation is still disputable. Here, we review the biological processes that have been proposed to explain pattern formation in arid ecosystems and how they have been implemented in mathematical models. We conclude by discussing the existence of similar structures in different biological and physical systems.