Trait Based Understanding Of Plant Species Distributions Along Environmental Gradients

Author : Jared Joshua Beck
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (124 download)

DOWNLOAD NOW!

Download or read book Factors Shaping the Distribution, Abundance, and Diversity of Temperate Forest Plants written by Jared Joshua Beck and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: More than a century after they emerged as central themes in ecology, community assembly and species coexistence remain rich areas of inquiry. Recent advances in coexistence theory and the development of new and powerful quantitative techniques have offered new insights into the varied processes shaping ecological communities. Here, I elucidate the processes driving community assembly in understory temperate forest plant communities. I first investigated how environmental conditions, functional traits, and phylogenetic relationships act together to influence plant distributions. Traits mediated plant distributions along environmental gradients, as expected, while phylogenetic relationships and niche differences had little effect on co-occurrence patterns. These findings reaffirm the importance of trait-mediated environmental sorting in determining plant distributions but call into question common assumptions about the roles of local niche differentiation and evolutionary history in plant community assembly. To build on this first project, I studied how two congeneric herbs, Hylodesmum glutinosum and H. nudiflorum manage to co-exist despite many similarities. Their broad-scale distributions reflect certain differences in morphology and physiology but there was little evidence of resource partitioning. Instead, patterns of co-occurrence and key demographic differences suggest equalizing processes that minimize competitive differences and life history tradeoffs promote local co-occurrence. I next examined local distributions of three forest herbs to understand the role of fine-scale environmental heterogeneity in structuring local plant distributions. These distributions matched a priori predictions based on differences in these species' morphology and physiology. Strong patterns of intraspecific spatial aggregation and heterospecific segregation coupled with limited dispersal capacity suggest these differential responses to fine-scale environmental variation could promote local coexistence among these species. Finally, I conducted an experiment to examine how plant-soil interactions influence herb growth. The effect of soil biota varied considerably among species providing evidence for both mutualistic and antagonistic interactions. These findings support the idea that plant-soil feedbacks play important but previously underappreciated roles in structuring herbaceous plant communities. Taken as a whole, my research illustrates how a diverse set of processes, operating at different rates and spatial scales, differentially affect various plant species to shape the overall distribution, abundance, and diversity of temperate forest herbs.