Many tree species worldwide are suitable for making biochar (BC), with planted eucalypts in particular being very productive and extensive. Above- and below-ground carbon sequestration by Eucalyptus plantations depends on plantation management options. An intensively managed cultivar could sequester over 100 mt of C/ha at a cost of $21–40/mt. BC production systems ranging in size from small mobile units to large centralized facilities and many kiln technologies influence the quality and price of the BC produced as well as the ability to control emissions. While BC from wood has many applications, its use as a soil amendment in forest plantations is appealing as a long-term sequestration strategy and opportunity to grow more robust trees and increase survival rates. Research in Florida USA and elsewhere addresses responses of forest and agronomic crops to wood BC soil amendments with and without other fertilizers. In combination with the carbon sequestered through tree growth, sequestration of 2.5 mt/ha of wood BC as a soil amendment in Eucalyptus plantations has estimated costs ranging from $3.30–5.49/ton of C.
Part of the book: Applications of Biochar for Environmental Safety
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.
Part of the book: Carbon Sequestration