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Pasturelands, often degraded, represent most of the converted lands globally. It is important to understand how different pasture management approaches can improve soil quality, increase feed production and farmer income. Here, the impact of different soil enhancers on soil quality and productivity of three cultivars of Brachiaria (Syn. Urochloa) forage grass is presented. Soil enhancers included: biochar - a carbon-rich product from biomass pyrolysis, moinha (local charcoal residue), traditional fertiliser containing nitrogen, phosphorus and potassium, lime, and forage peanut (Arachis pintoi cv. Amarillo). Considering the total biomass produced over the experiment (sum of four harvests), the highest dry biomass production was observed for Brachiaria brizantha cv. Piatã (14.1 Mg ha−1) and cv. Marandu (12.7 Mg ha−1), for biochar application of 30 Mg ha−1. Paiaguás had the highest dry matter production (12.4 Mg ha−1) for the treatment with forage peanut plus 15 Mg ha−1 of biochar. The increases in dry mass production translated to additional income, as compared with the control, of U$ 1 291, U$ 1 183 and U$ 991 per year for Marandu, Piatã and Paiaguás, respectively. The increases in forage grass productivity were reflected by positive changes in soil characteristics such as improvement in cation exchange capacity, pH and nutrient contents. Improved management of tropical pasturelands holds opportunity for more sustainable food production, and for ecosystem services protection and recuperation, for example, biodiversity net-gain, water regulation and carbon sequestration. [ABSTRACT FROM AUTHOR]

Greenhouse gas removal technologies are needed to reach the targets of the UNFCCC Paris Agreement. Among existing technologies, the use of biochar is considered promising, particularly biochar derived from the large quantities of sugarcane residues available in South America and elsewhere. However, the net greenhouse gas removal potential of sugarcane biochar has not been assessed hitherto. We use a scenario-based anticipatory life cycle assessment to investigate the emissions associated with a change from the combustion of sugarcane residues in a combined heat and power plant to the pyrolysis of these residues for biochar production and field application in São Paulo State, Brazil. We define scenarios based on different mean marginal electricity production and biochar production share. The results indicate that emissions from covering the electricity deficit generated by partial combustion of biomass during biochar production is the main emitting process. Overall, the processes associated with biochar production lower the net greenhouse gas benefits of the biochar by around 25%. Our analysis suggests that allocating 100% of the available sugarcane residues to biochar production could sequester 6.3 ± 0.5 t CO 2 eq ha−1 yr−1 of sugarcane in São Paulo State. Scaled up to the entire State, the practice could lead to the removal of 23% of the total amount of GHGs emitted by the State in 2016. • First LCA of sugarcane biochar for GHG removal in Brazil. • Covering the energy deficit created by pyrolysis is the most GHG emitting process. • Lifecycle emissions reduce the net carbon sequestration benefits of biochar by 25%. • Sugarcane residue biochar in São Paulo State, Brazil could sequester 36 Mt CO 2 eq yr−1. [ABSTRACT FROM AUTHOR]