R/EH-8

Strategic focus area:

Description:

*This project is a continuing project initially funded through award NA05OAR4171042 (year one) and currently funded through award NA10OAR4170072 (year two)* Objectives: In this project we will improve the understanding of mechanisms controlling plant response to prescribed burns in Chesapeake Bay tidal marshes. This information will allow land managers to improve prescribed burn management programs to improve the sustainability of tidal marsh restoration and conservation projects. The objective of this project is to elucidate the effects of the two primary mechanisms ash deposition and canopy removal-by which prescribed burns are thought to affect above and belowground plant growth. This proposal responds to the Ecosystem Processes research questions in the Maryland Sea Grant College Program 2009-2011 RFP. Methodology: The study will be conducted within a long-term prescribed burn study administered by the U.S. Fish and Wildlife Service at the Blackwater National Wildlife Refuge. We will leverage an ongoing study led by the U.S. Geological Survey (USGS) on elevation trajectories and associated marsh processes by establishing and sampling control and manipulated plots within no-burn and annual burn treatment units. Treatments will include ash deposition and canopy removal in unburned plots and shading in burned plots. Data will be collected on plant species composition, live and dead aboveground biomass, root growth, soils, soil temperatures, porewater nutrients, and nutrient availability. Data collection will be from winter 2009 to winter 2010. Rationale: Land managers in the Chesapeake Bay region are making multi-objective conservation and restoration decisions regarding prescribed burn frequency and implementation methods. A critical objective in these decisions is to stimulate plant growth and increase marsh surface elevation. This research will provide an improved understanding of the interactive effects of increased nutrient availability, soil temperatures, and light availability on plant growth following prescribed burns in this region. We anticipate that we will be able to quantify the relative contributions of ash deposition and canopy removal to the stimulation of plant production following prescribed burns. This information will allow us to make recommendations to land managers on optimal burn frequency and implementation strategies.