Evaluation of the potential for using old-field vegetation as an energy feedstock: Biomass yield, chemical composition, environmental concerns, and economics.

摘要

The major focus of current research on production of biomass for use as energy feedstock involves selection of species and genotypes best suited for specific regions of the United States and development of crop management techniques that maximize biomass productivity while minimizing environmental impacts and economic costs. The two experimental sites, and abandoned soybean field (AS) and an abandoned pasture (AP) were studied. At the AS site, the effects of two harvest frequencies (1 or 2 harvests annually), two nitrogen fertilizer treatments (1 or 2 harvests annually), two nitrogen fertilizer treatments (0 or 87 kg(center dot)ha(sup (minus)1)(center dot)yr(sup (minus)1)), and two phosphorous fertilizer treatments (0 or 111 kg(center dot)ha(sup (minus)1)(center dot)yr(sup (minus)1)) were determined. At the AP site, the effects of two harvest treatments (1 or 2 harvests annually), two fertilizer treatments (56:56:135 kg of N:P:K(center dot)ha(sup (minus)1)(center dot)yr(sup (minus)1)), and two lime treatments (0 or 4600 kg(center dot)ha(sup (minus)1)(center dot)yr(sup (minus)1)) were determined. At both sites, treatments were arranged in a randomized complete block 2 (times) 2 (times) 2 factorial experiment. The results of this research indicated that old-field vegetation is: (1) sufficiently productive to provide significant quantities of energy feedstock; (2) chemically suitable as an energy feedstock; (3) environmentally benign with respect to impacts related to soil erosion and nutrient depletion; (4) relatively unresponsive to fertilizer and lime inputs; and (5) economically competitive with other biomass energy feedstock candidates. 38 refs., 8 figs., 68 tabs.