Christopher W. Woodall and Greg Liknes. USDA Forest Service, Northern Research Station, 1992 Folwell Ave, St. Paul, MN 55108
Coarse and fine woody materials (CWD and FWD) are substantial forest ecosystem carbon stocks; however, there is a lack of understanding about how these detritus carbon stocks vary across forested landscapes. Because forest detritus production and decay rates are partially dependent on climatic conditions, the accumulation of CWD and FWD carbon stocks in forests may be correlated with climate. Therefore, this study uses a nation-wide inventory of CWD and FWD in the United States to examine how these carbon stocks vary by climatic regions and variables. Mean CWD and FWD forest carbon stocks vary by Köppen’s climatic regions across the United States. Regions with the highest carbon stocks have cool summers while regions with the lowest carbon stocks were found in arid desert/steppes or temperate humid regions. CWD and FWD carbon stocks are positively correlated with available moisture and negatively correlated with maximum temperature. CWD and FWD C stocks are at risk of becoming net C sources under a global climate warming scenario as increases in CWD or FWD production may be more than offset by increases in forest detritus decay rates.