Print PageIncreasing interests and demands for alternative source of energy has renewed interest in short rotation woody plantation for biofuel feedstock. Poplar is one of the most preferred woody species because of its fast growth, short rotation/coppice capability, broad adaptation to edaphic conditions, available genome sequence and transformation techniques. But there are many constraints on growing short rotation poplar plantation including land availability. Marginal land, or land unsuitable for sustainable row-crop production, is considered suitable for short rotation poplar plantation. The objective of this study is to compare the allometric relationships and productivity of two common poplar species on marginal land and nearby agriculture land.
The experimental design is 18 plots on the site, of which 9 have clone D105 (native) and the other 9 have NM6 (hybrid). Allometric equations were developed for two clones using standard field procedures. Aboveground net primary production (ANPP) for the trees was estimated for each poplar clone. Understory NPP was estimated from clipped plots (50 cm x 120 cm) in each of 18 plots.
Results/Conclusions
All the allometric equations were significant (p<0.0001) and had R2 values between 0.65 and 0.98. Stem biomass equations for two clones did not differ significantly (α>0.05) and therefore one general equation was composed. Equations for branch and foliage biomass differed significantly (α≤0.05) between clones and therefore separate equations were composed for each clone. Aboveground net primary productions of the two clones were estimated using these equations. ANPP for D105 and NM6 is 5.23 Mg/ha and 12.16 Mg/ha, respectively.
Aboveground carbon allocation pattern of D105 was 83-89% for stem, 8-15% for branch, and 2-3% for leaves, and for NM6 was 73-74% for stem, 22-23% for branch, and 3-4% for leaves. For a similar DBH, clone NM6 produced higher stem, branch and foliage biomass than clone D105.
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