Posted: Mon Feb 04, 2013 12:24 pm
by KoutaR
eliahd24 wrote:This is very interesting Kouta. I'd be curious to see how forest of the southern Appalachians stack up- such as those old groves in the Smokies. Do any NTSers have any data on forest biomass for the eastern US?

I found two studies on this topic. The first one is Whittaker, R. H. (1966): Forest dimensions and production in the Great Smoky Mountains. Ecology, Vol. 47, No. 1, pp. 103-121. The second one is Busing, R. T., Clebsch, E. E. C. & White, P. S. (1993): Biomass and production of southern Appalachian cove forests reexamined. Can. J. For. Res. 23: 760-765. The latter appears to be more reliable: newer methods, larger sample plots; in addition, the plots and the data are partly the same; Busing, Clebsch and White have analysed Whittaker's data with better methods.

The highest estimate is 621 t/ha at Surrey Fork at 870 meters in Tsuga-Acer-Fagus-Aesculus forest. However, the plot size is only 0.1 ha. The highest value for a plot about 1 ha is 471 t/ha at Roaring Fork at 1140 meters in Tsuga-Halesia-Aesculus forest. The plot size is 1.0 ha.

Leaves and branches have been included in the estimates. According to the authors, the most massive plots are located in particularly densely wooded areas in old-growth forests.

I must decrease my estimate for an exceptional European old-growth forest. My estimate was based on Leibundgut's data from Perucica Nature Reserve. He only gives estimates for stem volumes. I calculated biomasses from the wood densities and estimated the understory and leaf biomasses from the values and the percentages of the Picea-Tsuga stand in Oregon. The latter was a mistake because the forests with an important Fagus-component has much sparser understories and also less leaf biomass. My new best guess is 700 t/ha. Fagus has much denser wood than conifers, and Abies alba reaches large dimensions and may grow in dense stands. I changed the value in my text above.