Bioenergy crop production on reclaimed mine land in the North Appalachian region, USA

There is a growing interest in converting marginal lands to bioenergy crop production instead of using high quality croplands which could jeopardize food security and soil quality. Miscanthus (Miscanthus x giganteus Greef & Deuter ex Hodkinson & Renvoize) is a promising feedstock due to its high biomass production under temperate climate and a wide range of soil properties. Appalachian region contains about 1.1 million hectares (Mha) of reclaimed minesoils (RMS) that can be used to produce bioenergy crops and spare arable lands for food production. This study was conducted on 27 years old RMS which was converted to corn and miscanthus land uses in 2013. We assessed the growth performance (plant populations, height, tillers), and aboveground dry biomass (AB) yields of miscanthus and corn (Zea mays L.) compared to antecedent meadow under reclaimed mined land (RML) as affected by different fertilization practices during the first three years of establishment of corn and miscanthus. Results show that the growth and AB yields did not significantly vary between source (synthetic and organic) and rate of nitrogen applications (0, 75, 150, 225 kg N h−1) within each land-use. For the first three years meadow and corn on average had a 30% higher cumulative potential AB harvest compared to miscanthus (12.2 Mg ha−1). Miscanthus generally takes about three years to establish good stand. However, miscanthus had the highest AB yields in the third year (19.6 Mg ha−1) and is expected to maintain higher yields than the meadow (8.0 Mg ha−1) and corn (8.3 Mg ha−1) land-uses, resulting in a greater harvestable AB yield potential in the long-term. Continued monitoring of AB yields is critical to determining whether sustained yields can be maintained with little or no inputs in RML.