Integrating Landscape-scale Forest Measurements with Remote Sensing and Ecosystem Models to Improve Carbon Management Decisions

Research Issue

Managing forests to increase carbon stocks and reduce emissions requires knowledge of how management practices and natural disturbances affect carbon pools over time, and cost-effective techniques for monitoring and reporting.  This study improves upon the methodology to collect and integrate the multi-tier monitoring data from the North American Carbon Program (NACP) with management decisions by systematically scaling up intensive forest carbon measurements to land management areas (or landscapes), and reconciling these estimates with ecosystem models and decision-support systems that are driven by remote sensing and national inventories.  Monitoring systems for carbon stocks and fluxes in the NACP include a multi-tier hierarchy of observation methods: flux towers, landscape biometrics, inventories, and remote sensing.   

Our Research

Our approach involves (1) strengthening the connection between field measurements, simulation modeling, and remote sensing, (2) closing the carbon budget at selected sites and multiple scales by using and reconciling multiple estimation approaches, and (3) linking data and research models to decision support systems.  The data foundation of this integrated research is a network of field sites with flux towers and intensive biometric measurements of carbon stocks and soil CO2 fluxes, airborne LIDAR remote sensing, Landsat-TM and MODIS products, and in-situmeasurements scaled up to landscapes based on statistical methods and models (Birdsey et al. 2004 available at https://www.fs.fed.us/research/efr/publications/Birdsey-DOE-EFR-C-2004.pdf).  The biometric measurements at these sites, termed “Tier 3” sites in the North American Carbon Program science plan, are intended to integrate the spatially extensive, but coarsely resolved, measurements made through remote sensing and forest inventory with the spatially intensive and highly resolved measurements made at AmeriFlux sites.  The “benchmark” sites provide parameters and validation for ecosystem models, which in turn provide the basic information that is needed by decision-support tools for policy and management.    

This research builds upon a foundation of work begun in 2001 by the U.S. Forest Service to implement a forest carbon monitoring and observation system at the FS network of Experimental Forests. Landscape monitoring sites were selected to represent a variety of managed and unmanaged forest conditions in different physiographic regions, so that the methods could be thoroughly tested using a representative range of landscapes.  Most of the sites have flux towers and all have maps of vegetation structure from LIDAR and processed imagery from Landsat-TM and MODIS subsets. At each of the sites we use biometric measurements to monitor the carbon pools that contribute most to annual changes in productivity: remeasurement of the tree diameters and heights at the original sample plot locations to obtain estimates of woody biomass increment; and measurements of litterfall and soil CO2 flux.  We use spatial analysis techniques and an ecosystem process model (PnET-CN) to scale up and map observations from flux towers, landscape biometrics, and inventories to areas of approximately 2500 km2 around flux tower sites. With a network of sites that represent different managed forests of the U.S., we envision a set of “benchmark” estimates that can efficiently and reliably document the expected effects of management decisions on the most important carbon pools, and separate these effects from natural factors such as climate variability.

The Northern Research Station has several participating research sites:

1. The Bartlett Experimental Forest
2. The Silas Little Experimental Forest
3. The Marcell Experimental Forest

This research is linked to the NRS Flux Tower network. 

Expected Outcomes

The final review draft assessment report on the state of the carbon cycle of North America addressed needs for decision support for forest carbon management, concluding that “Decisions concerning carbon storage in North American forests and their management as carbon sources and sinks will be significantly improved by (1) filling gaps in inventories of carbon pools and fluxes, (2) a better understanding of how management practices affect carbon in forests, (3) better estimates of potential changes in forest carbon under climate change and other factors, and (4) the increased availability of decision support tools for carbon management in forests.” 
Key information for decision-support tools includes (1) estimates of carbon stocks and quantified impacts of management activity; (2) estimates of net ecosystem production (NEP) and changes in carbon pools; and (3) estimates of forest/atmosphere carbon fluxes and relevant effects from various environmental controls. This work is relevant to land managers and climate change policy because it supports a need to estimate and report carbon stocks and changes in carbon stocks to state, regional, national, and private greenhouse gas registries.  This work also develops large-scale ground truth sites for future NASA missions.  

Bradford, J., L. Joyce, R. Birdsey, and M. Ryan.  2007.  Tree age, disturbance history and carbon dynamics in sub-alpine Rocky Mountain forests. (in prep)

Research Results

Birdsey, R.A., J.C. Jenkins, M. Johnston, E. Huber-Sannwald, B. Amero, B. de Jong, J.D.E. Barra, N. French, F. Garcia-Oliva, M. Harmon, L.S. Heath, V.J. Jaramillo, K. Johnsen, B.E. Law, E. Marín-Spiotta, O. Masera, R. Neilson, Y. Pan, and K.S. Pregitzer, 2007: North American Forests. In: The FirstState of the Carbon Cycle Report (SOCCR): The North American Carbon Budget and Implications for the Global Carbon Cycle. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research [King, A.W., L. Dilling, G.P. Zimmerman, D.M. Fairman, R.A. Houghton, G. Marland, A.Z. Rose, and T.J. Wilbanks (eds.)]. National Oceanic and Atmospheric Administration, National Climatic Data Center, Asheville, NC, USA, pp. 117-126.

Birdsey, Richard A.; Cook, Robert; Denning, Scott; Griffith, Peter; Law, Beverly; Masek, Jeffrey; Michalak, Anna; Ogle, Stephen; Ojima, Dennis; Pan, Yude; Sabine, Christopher; Sheffner, Edwin; Sundquist, Eric. 2007. Investigators share improved understanding of the North American carbon cycle. American Geophysical Union. 88(24): 255.

Birdsey, Richard A.  2006. Carbon accounting rules and guidelines for the United States forest sector. Journal of Environmental Quality.  35: 1518-1524. 

Birdsey, R., R. Kolka, M.L. Smith, M. Ryan, D. Hollinger, L. Heath, and C. Hoover.  2004.   Landscape carbon monitoring and analysis at the experimental forest network.  Proceedings of the 3rd Annual Conference on Carbon Sequestration.(electronic only)  Alexandria, VA May 2004

Potter, C.; Klooster, S.; Hiatt, S.; Fladeland, M.; Genovese, V; Gross, P. 2006a, Satellite-derived estimates of potential carbon sequestration though afforestation of agricultural lands in the United States, Climatic Change (In Press).

Potter, C., S. Klooster, R. Nemani, V. Genovese, S. Hiatt, M. Fladeland and P. Gross, 2006b, Estimating Carbon Budgets for U.S. Ecosystems, Eos Transactions American Geophysical Union, 87(8), 85-96.

Pan, Yude; Birdsey, Richard; Hom, John; McCullough, Kevin; Clark, Kenneth.  2005. Improved estimates of net primary productivity from MODIS satellite data at regional and local scales. Ecological Applications.  16(1): 125-132. 

Ryan, MG; Law, BE.  2005.  Interpreting, measuring and modeling soil respiration.  Biogeochemistry 73: 3-27 

Research Participants

Principal Investigator

• Richard Birdsey, US Forest Service – Northern Research Station Program Manager 
• David Hollinger, US Forest Service – Northern Research Station Plant Physiologist
• John Bradford, US Forest Service – Northern Research Station Research Ecologist 
• Randall Kolka, US Forest Service – Northern Research Station Research Soil Scientist 
• John Hom, US Forest Service – Northern Research Station Biological Scientist 
• Yude Pan, Research Forester, US Forest Service - Northern Research Station
• Ken Clark, Research Forester, US Forest Service – Northern Research Station 

Research Partners

• Chris Potter, NASA Ames Research Center 
• Michael Ryan, Rock Mountain Research Station 
• Steven McNulty, Southern Research Station 
• Steven Klooster, University of California 
• Scott Ollinger, University of New Hampshire

For further details log on website :
https://www.nrs.fs.fed.us/clean_air_water/monitoring_carbon/Landscape_scale_forest_measurements/