Doctor of Philosophy (Ph.D.)
Virginia Institute of Marine Science
James E. Perry
Forested headwater wetlands provide numerous ecosystem functions and services and are often disturbed, impacted, or destroyed due to their position in the landscape. This has led to many successful and unsuccessful attempts to restore these important ecosystems. Returning trees to these restored ecosystems has proven to be particularly challenging. to increase successful forested headwater wetland restoration, this dissertation recommends tree species and stocktypes that could be planted to return lost ecosystem structure and ecological functions. This dissertation focuses on a created experimental system that investigates the responses of seven species of native wetland trees planted using three stocktypes in three distinct hydrologic conditions (normal rainfall, constantly saturated root zone, and flooded above the root crown). This dissertation has been divided into six chapters to facilitate investigation of several research questions.;The first chapter provides an in depth literature review of forested wetland restoration, highlighting wetland regulations, factors influencing planted trees and the various responses that will be measured in the subsequent chapters. The second chapter investigates survival and morphological development five years following planting and provides recommendations for planting based on these responses.;The third chapter in this dissertation develops a biomass estimation model that relates total biomass to stem morphology based on destructive harvests. The model is then used to determine the biomass accumulated of all living trees after six years allowing for a robust evaluation of each species and stocktypes' response to the hydrologic treatments. Building upon the model developed in chapter three, the fourth chapter calculates biomass accumulation rates which provide greater insight to how these species develop and change through time.;The fifth chapter investigates the regulatory context for wetland compensatory mitigation standards in Virginia and provides an additional ecological performance standard for evaluating compensatory mitigation site success. This performance standard is based on stem morphology and provides a robust method for evaluating the ecological functioning of compensatory mitigation sites. Finally the sixth chapter provides a brief economic analysis that examines the return on investment for each species and stocktype used in the study and provides overarching conclusions based on the preceding chapters.;The combination of these chapters provides an in-depth analysis of the responses of these planted trees to the experimental hydrologic conditions from the time of planting through six years of growth. These analyses yielded practical and regulatory recommendations that can enhance forested wetland restoration.
© The Author
Hudson, Herman W., "Development of forested wetland ecological functions in a hydrologically controlled field experiment in Virginia, USA" (2016). Dissertations, Theses, and Masters Projects. William & Mary. Paper 1539616703.