• Conducted forest and soil assessments at Liping, Changbaishan, Heihe and Xingguo sites
• Completed remote sensing and carbon modeling for all three core sties
• Collected social and economical data and conducted household survey at three core sites and conducted IA for these sites
• Completed remote sensing image processing for all China’s landmass
• Completed NPP mapping and obtained a preliminary carbon source and sink map of China.
• Investigated carbon dynamic modeling for the last 100 years and future 100 years
  

• Changbaishan workshop to identify gaps and link three components (took place 20-23 June)
• Meeting with climate change policy makers
• Policy workshop in Toronto (May-July, 2005)
• Policy workshop in Beijing (July-August, 2005)
• Complete IA work at all three sites and produce policy recommendations (revisit all three sites)
• Conduct forest/soil assessments and remote sensing and carbon modeling for Dunhua
• Refine and validate carbon results at three sites (revisit Liping)
• Finalize the national level carbon modeling

Ground-based measurements of LAI in 27 plots are used to develop remote sensing algorithms for retrieving LAI using a Landsat TM image covering the Changbaishan Natural Reserve. The net primary productivity (NPP), which quantifies the net gain of carbon in living biomass each year, is modeled with the Boreal Ecosystem Productivity Simulator (BEPS) with additional inputs of soil texture, topography, and daily meteorological data. The modeled NPP agrees well with the measured values at 10 ground plots (Figure 1). The NPP distribution within and around the Reserve is shown in Figure 2.

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Figure 1. Comparison of measured and modeled NPP using the BEPS model	Figure 2. NPP distribution within and around the Changbaishan Natural Reserve based on a Landsat TM image and the BEPS model.

NPP maps are first produced with high-resolution remote sensing images (Landsat TM, ASTER) for four ground sites at Changbaishan in Jilin Province, Liping in Guizhou Province, Heihe in Gansu Province, and Xingguo in Jianxi Province. These maps are used to validate a national NPP map produced using moderate-resolution (1 km) remote sensing images (MODIS). This national NPP map in 2001 is the key input to the Integrated Terrestrial Carbon Cycle Model (InTEC) for estimating the carbon source and sink distribution in China’s forests (Figure 3). Other inputs to the model include: (1) monthly climate data for the last 100 years, (2) a land cover map in late 1990’s; (3) a leaf area index map for the growing season of 2001; (4) a soil texture map; (5) a soil organic carbon map; (6) a nitrogen deposition map; and (7) a forest age map. The total annual carbon balance in China’s forests in the last 100 years is shown in Figure 4. China’s forests have been collectively a large carbon sink due to regrowth in reforested areas in the last 2-3 decades.

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Figure 3. Carbon source and sink distribution in China’s forests in 2001.	Figure 4. Historical variation in China’s forest carbon balance. Regrowth of forests planted in 1970-2000 is the main reason for the increase in carbon sinks.