Biochar amendment improves degraded pasturelands in Brazil: environmental and cost-benefit analysis

Agnieszka E Latawiec,Everaldo Zonta,Aline F Rodrigues,Sarah E Hale,Ednaldo Araujo,Ana Castro,Gustavo A Malaguti,Bernardo B N Strassburg,André B Junqueira,Etelvino H Novotny,Luis Gustavo Barioni,Gerard Cornelissen,Catarina Jakovac,Helena A N Pinto,Jose Guilherme Guerra,Nilcileny Batista,Marcio Rangel,Luiz Fernando D De Moraes,Maiara Mendes

doi:10.1038/s41598-019-47647-x

Abstract

Most deforested lands in Brazil are occupied by low-productivity cattle ranching. Brazil is the second biggest meat producer worldwide and is projected to increase its agricultural output more than any other country. Biochar has been shown to improve soil properties and agricultural productivity when added to degraded soils, but these effects are context-dependent. The impact of biochar, fertilizer and inoculant on the productivity of forage grasses in Brazil (Brachiaria spp. and Panicum spp.) was investigated from environmental and socio-economic perspectives. We showed a 27% average increase in Brachiaria production over two years but no significant effects of amendment on Panicum yield. Biochar addition also increased the contents of macronutrients, soil pH and CEC. Each hectare amended with biochar saved 91 tonnes of CO2eq through land sparing effect, 13 tonnes of CO2eq sequestered in the soil, equating to U$455 in carbon payments. The costs of biochar production for smallholder farmers, mostly because of labour cost, outweighed the potential benefits of its use. Biochar is 617% more expensive than common fertilizers. Biochar could improve productivity of degraded pasturelands in Brazil if investments in efficient biochar production techniques are used and biochar is subsidized by low emission incentive schemes.

Highlights

Most deforested lands in Brazil are occupied by low-productivity cattle ranching
Brazilian cattle ranching is characterized by low stocking rates, mostly below 1 animal unit (AU) per hectare (1 AU = 0.7 animal), a rather low number comparing with other meat-producing countries[3]
This study investigates biochar amended to Brazilian pasturelands with the aim of increasing yield of the two most common forage grasses in Brazil; Brachiaria brizantha cv

Summary

Introduction

Most deforested lands in Brazil are occupied by low-productivity cattle ranching. Brazil is the second biggest meat producer worldwide and is projected to increase its agricultural output more than any other country. Degraded Brazilian pasturelands have impacts beyond the country level Together with agriculture, they are linked to deforestation and biodiversity loss at an unprecedented scale, and greenhouse gases emissions of global significance[9]. In Brazil, pastureland productivity could be tripled in much more sustainable ways[3], providing meat and other commodities while reversing environmental degradation This is important for smallholders who represent the majority (70%) of cattle ranchers in Brazil and often strive to maintain profits. The Brazilian Native Vegetation Protection Law and governmental commitments[12] oblige producers to spare land for conservation This may generate competition for land as many producers strive to continue with low-productivity cattle ranching to meet the ever-increasing national and international demands for meat, while simultaneously seeking to keep a part of their land covered with native vegetation. Including the valuation of soil ecosystem services into decision making is paramount for minimizing carbon emissions, and for improving local livelihoods and promoting food security

Methods

Results

Conclusion