01635nas a2200157   4500008004100000245009600041210006900137300001300206490000700219520106200226653002201288100002001310700001701330700001801347856011201365       1985                        eng d00aAn evaluation of beta attenuation for estimating aboveground biomass in a tallgrass prairie0 aevaluation of beta attenuation for estimating aboveground biomas  a556 -5580 v383 a<p>The attenuation of beta particles by vegetation was evaluated as a nondestructive method for estimating aboveground biomass in tallgrass prairie in northeast Kansas. Regression equations using the sum of beta attenuation measurements for each of 5 height classes within the vegetation and mean midday leaf water potential as the independent variables were used to predict live and total biomass. Live and total biomass were better predicted on burned (r2=.91 and .88, respectively) and unburned sites (r2=.71 and .70, respectively). Greater variability in the relationship between beta attentuation and biomass in unburned prairie was a result of the large and variable amount of dead biomass on unburned sites. Dead biomass was poorly predicted by beta attentuation (r2=.24- .49). Beta attentuation predicted biomass in burned tallgrass prairie within +/- 5% of harvest values until late season vegetative senescence. In unburned prairie, predictions were poorer, but the technique could still be useful if the required accuracy need be only +/- 25%</p>10atallgrass prairie1 aKnapp, Alan, K.1 aAbrams, M.D.1 aHulbert, L.C.  uhttp://knz.lternet.edu/content/evaluation-beta-attenuation-estimating-aboveground-biomass-tallgrass-prairie