Ground cover and biomass projection photos for the BBC collapse scar

We used digital photographs to project the biomass over the growing season. This data set contains ground cover photos of plots from the center of the BBC collapse scar (0m) into the surrounding fire scar (30m) of the Survey Line Fire (burned in June-July 2001) for the growing seasons of 2003 and 2004. Also included are ground cover photos of plots along the biomass transect used to create the projected biomass data. We calculated the percent cover of vegetation for the biomass and intensively monitored transects from digital photographs. Photographs were rectified to 10,000 x 10,000 pixels and a 20 x 20 grid was applied to the photograph. The percentage of each plant type was estimated in each grid cell. The percent cover was regressed against the measured dry biomass to project biomass for the intensively measured transect. We did not project moss biomass and instead assumed it to be the same for both transects. We projected the change in biomass over the growing season from the change in greenness determined from digital photographs. We chose five dates throughout the growing season with pictures of equal color saturation, focus and aspect. From these we estimated the percent photosynthetic biomass by selecting areas of green on the photograph and calculating the percentage of the total pixels made up by these areas. We estimated curves for the change in % green vegetation for 0, 6 m and the mean of the remaining distances along the transect (12, 18, 24, and 30 m), as these regions of the transect exhibited different patterns of greenness across the growing season of 2004. To estimate photosynthetic biomass over the growing season, we corrected the biomass estimates for the study transect to account for the change in green vegetation associated with growth and senescence