| NSF Org: |
DEB Division Of Environmental Biology |
| Recipient: |
|
| Initial Amendment Date: | February 12, 2019 |
| Latest Amendment Date: | December 23, 2021 |
| Award Number: | 1910811 |
| Award Instrument: | Standard Grant |
| Program Manager: |
Kirsten Schwarz
DEB Division Of Environmental Biology BIO Directorate for Biological Sciences |
| Start Date: | February 15, 2019 |
| End Date: | January 31, 2023 (Estimated) |
| Total Intended Award Amount: | $197,083.00 |
| Total Awarded Amount to Date: | $228,807.00 |
| Funds Obligated to Date: |
FY 2022 = $31,724.00 |
| History of Investigator: |
|
| Recipient Sponsored Research Office: |
801 UNIVERSITY BLVD TUSCALOOSA AL US 35401-2029 (205)348-5152 |
| Sponsor Congressional District: |
|
| Primary Place of Performance: |
801 University Blvd. Tuscaloosa AL US 35478-0104 |
| Primary Place of
Performance Congressional District: |
|
| Unique Entity Identifier (UEI): |
|
| Parent UEI: |
|
| NSF Program(s): |
Cross-BIO Activities, Ecosystem Science |
| Primary Program Source: |
01001920DB NSF RESEARCH & RELATED ACTIVIT |
| Program Reference Code(s): |
|
| Program Element Code(s): |
|
| Award Agency Code: | 4900 |
| Fund Agency Code: | 4900 |
| Assistance Listing Number(s): | 47.074 |
ABSTRACT
The Southern Longleaf Pine Ecosystem once covered much of the southeastern coastal plain and is the most diverse forest ecosystem in the temperate zone. Hurricanes are important and frequent disturbances in southeastern U.S. ecosystems, and were important in shaping pre-settlement ecosystems. Hurricanes significantly damage forests as the hurricane makes landfall and moves inland. The damage extent varies with both hurricane characteristics and forest composition and structure. Hurricane Michael moved across the Northern Gulf of Mexico in 2018, resulting in catastrophic winds (Category 2 force) that reached over 100 miles inland and caused extensive damage along its path. The storm's impact to forests varied with local conditions (e.g. soil, topography) and the forest management strategies present across this area. The implications of this damage to the carbon, water, and energy cycles of these forests, the relationships between impacts, storm intensity, and forest management, and how the forests will recover are poorly understood. This RAPID award will explore how the physical and ecological changes from hurricane damage affect the coupled biogeochemical cycles of these forests. This award will provide local and regional forestry and resource managers, conservation professionals, policy makers, timber industry representatives, and small private landowners practical understanding of hurricane impacts and the potential for recovery based on demonstrations, development of management strategies, and potential policies for natural resource management and conservation.
The primary goal of this RAPID award is to determine the disturbance-related shift in ecosystem structure and function as it relates to the resilience of the longleaf pine savanna from disturbances such as hurricanes. In southern Georgia and northern Florida, Hurricane Michael damaged longleaf pine forests by downing whole trees and resulted in extensive loss of branches and leaves. Efforts to maintain and restore longleaf pine ecosystems in this regional include long-term studies that show the importance of its ecosystem services, including carbon, water and energy exchange. Three of these long-term forest sites in the southeastern NEON domain were in the hurricane path and are proposed to study the mechanistic controls on carbon, energy, and water cycling following the extensive hurricane damage. Using these sites, this study will provide a vulnerability assessment of the effects of hurricanes and an understanding of ecological resilience using thermodynamic metrics. The award will explore fundamental thermodynamic concepts to understand the impacts and explain the resilience and recovery of these forests.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
PUBLICATIONS PRODUCED AS A RESULT OF THIS RESEARCH
Note:
When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external
site maintained by the publisher. Some full text articles may not yet be available without a
charge during the embargo (administrative interval).
Some links on this page may take you to non-federal websites. Their policies may differ from
this site.
PROJECT OUTCOMES REPORT
Disclaimer
This Project Outcomes Report for the General Public is displayed verbatim as submitted by the Principal Investigator (PI) for this award. Any opinions, findings, and conclusions or recommendations expressed in this Report are those of the PI and do not necessarily reflect the views of the National Science Foundation; NSF has not approved or endorsed its content.
Hurricane Michael made landfall on the Florida panhandle in 2018, and sustained Category 2 force winds over 100 miles inland. The hurricane crossed the Jones Center at Ichauway (JCI), a 11,000 ha longleaf pine research center, substantially altering forest structure by downing whole trees and reducing canopy leaf area. The primary goal of this project was to assess the resilience of the longleaf pine savanna to this extreme event. We hypothesized that more pristine sites would recover more rapidly than those with greater human legacy effects, and that stands on drier soils, those that were more distant from forest edges, and those with lower tree density would show evidence of greater resistance to the storm. Through intensive measurements taken a decade pre-storm, and during 2-years post-storm, we assessed changes in carbon, water, and energy exchanges at four sites at JCI, and quantified forest structure change across the Center.
We found that tree damage was associated with topography and soil moisture. Ground-based data confirmed that the hurricane caused a 3% - >30% loss of forest basal area, and was lowest on shorter-stature, less dense sand ridges and highest in floodplain and hardwood-dominated depressions. Using data collected via LiDAR (Light Detection and Ranging, a remote sensing method that uses light in the form of a pulsed laser), we analyzed changes in forest canopy height. These data showed that our low soil moisture (xeric) site had the least damage while a higher soil moisture site with significant anthropogenic legacy (intermediate) had the greatest damage. Measurements of leaf area index (the total area of leaves per unit ground area) indicated that the storm removed 33-36% of leaf area at our study sites. However, one year following the storm, LAI at was ~8% lower the xeric site than pre-storm while that of the higher moisture (mesic) site’s LAI remained ~33% lower.
Carbon dynamics were assessed in terms of gross ecosystem exchange (GEE; the gross carbon uptake by photosynthesis), ecosystem respiration (Reco; the total CO2 release due to respiration processes), and net ecosystem exchange (GEE minus Reco). Statistical models were used to compare these components of carbon dynamics pre- and post-storm. We found that the xeric site’s NEE was stable, while the mesic site NEE increased post-storm. GEE was higher in the mesic site but decreased post-storm, while Reco was higher in the xeric site but increased post-storm. This shows that………
Salvage logging of downed stems was performed at the mesic site, but not at the xeric site, since it was not found to be cost-effective. Using estimates of the amount of downed wood on the site, we estimated that it will take ~10 years for the xeric site to recover the biomass it lost during Hurricane Michael. Accounting for salvage logging and downed wood, the mesic site may take from >10 to 35 years to return to pre-storm biomass and stand structure due to wind damage. However, its recovery time will depend on the recovery of physiological activity at the site, understory activity, and the growth of seedlings, which are determined by environmental pressures and the system’s resilience. Return to pre-storm biomass also depends on the occurrence and frequency of other disturbances events, both of which would slow recovery.
This collaborative project involved a diverse group of scientists, technicians, and students across several institutions. This project provided an opportunity for four post-graduate employees at JCI to gain additional field and laboratory skills, including the use of precision forestry field measurement equipment, aerial imagery and GIS. One Ph.D, five M.S., and two undergraduate students have also been trained on the project, gaining skills in carbon flux measurement techniques, plant ecology, atmospheric sciences, remote sensing, GIS, ecosystem ecology, physiological ecology, and statistical analysis. Project data have also been used to educate students about the effects of hurricane disturbances in forested systems. Project results have been disseminated at national conferences, and documented in peer-reviewed publications and data products prepared for serving to forest managers and scientists. The project contributed to educating a new generation of scientists through research and cross-disciplinary training.
Last Modified: 05/22/2023
Modified by: Gregory Starr
Please report errors in award information by writing to: awardsearch@nsf.gov.
