On Growth and Form: Mathematical Models of Plant Strategies

Abstract

Plants are engaged in a competitive game for access to light. This has resulted in the evolution of growth strategies that enable plants to compete for light in a range of conditions. Early successional species must be able to efficiently colonize open space and quickly grow in height, while late successional species must be able to survive in the understory and slowly replace early successional species. This dynamic has led to different adaptations in early and late successional species. Using mathematics, we can investigate which strategies may be beneficial and model how these strategies are implemented. In Chapter 1, we develop a model of fire-prone ecosystems and show that early successional species may benefit from increasing their flammability because this can kill late successional trees in their understory. Chapters 2 and 3 use mathematical models to reproduce patterns of primary and secondary growth, respectively. These models are then incorporated into a larger model of plant growth in Chapter 4, which is then used to predict the optimal growth behavior of early successional plants. We find that plant architecture has a significant impact on plant performance and competitive ability, with the most successful plant forms having growth algorithms that lead to high productivity and height growth.