Carbon Sequestration by Eucalypts in Florida, USA: Management Options Including Biochar and Associated Economics

Abstract

Growth and economic models for E. grandis in mulch wood rotations, for E. grandis and E. grandis x E. urophylla cultivars grown as short-rotation woody crops (SRWC), including coppicing, for E. grandis in windbreaks (WB), with and without soil amendments including biochar (BC) and the slow-release fertilizer Green Edge (SRF, GE), and for E. grandis in dendroremediation applications estimated the above- and below-ground carbon sequestration potentials of these management options. The cultivars may sequester over 10 Mg of C/ha/year as SRWCs. Under assumed management costs and market conditions, SRWC management with BC is more profitable than operational culture if BC application costs are ≤$450/Mg. Longer rotations with less intensive management result in lower but still considerable sequestration and economic benefit. In WBs, E. grandis cultivars may sequester up to 34 Mg of C/ha in 3 years, with additional sequestration by amending soil with BC, GE, and BC + GE. Amending soil with BC derived from eucalypts is both a long-term sequestration strategy and an opportunity to increase plantation and crop productivity. Demand for sustainably produced BC is growing due to multiple applications beyond soil carbon sequestration.