Grant: Discovery Grants Program - Individual

Plant species distributions are the product of a variety of factors including local environmental conditions, regional processes, historical events, and climatic conditions. Specific plant traits (e.g., resource use efficiencies, metabolic costs, tissue turnover, etc.) have been linked to species distributions along single resource gradients repeatedly and play a crucial role in determining species success as a function of abiotic resource availability. Despite extensive work in this area, our knowledge is limited with respect to potential trade-offs underlying the ability to tolerate scarcity or excess of one resource versus that of another. Likewise, it is not clear whether similar traits and tradeoffs dictate species distributions across spatial scales. The main objective of the proposed research will be the determination of plant traits that contribute to species distributions both locally and geographically and the relationships among relevant traits and trade-offs at these two scales in three main systems: tropical and temperate forests and coastal marshlands. Research will fall into two main topics: (1) Determination of mechanistic bases of local distribution (i.e., habitat preference) vs. geographic distribution (i.e., range size); and (2) Quantification of multiple resource tolerance trade-off surfaces. For each component of the study detailed investigation of trait plasticity and performance in relation to a variety of resource gradients will be monitored. This will allow for a cross-system examination of local and regional distributions as a function of plasticity of traits and therefore result in more broadly applicable results. Quantification of resistance trade-offs and relationships between local and geographic species distributions will provide the framework for assessing species suitability for restoration efforts in degraded systems such as the Acadian forests of Eastern Canada. Finally, understanding determinants of range size may provide new insights into mechanisms enabling the spread of invasive species.