Author(s): Megan C. Evans, Josie Car­war­dine, Rod J. Fen­sham, Don W. But­ler, Ker­rie A. Wil­son, Hugh P. Poss­ing­ham, Tara G. Martin

Title: Car­bon farm­ing via assisted nat­ural regen­er­a­tion as a cost-effective mech­a­nism for restor­ing bio­di­ver­sity in agri­cul­tural landscapes

Year: 2015

Pages: 114–129

Pub­li­ca­tion type: jour­nal article

Lan­guage: English

Source: http://www.sciencedirect.com/science/article/pii/S1462901115000222

Abstract:

Car­bon farm­ing in agri­cul­tural land­scapes may pro­vide a cost-effective mech­a­nism for off­set­ting car­bon emis­sions while deliv­er­ing co-benefits for bio­di­ver­sity through ecosys­tem restora­tion. Refor­esta­tion of land­scapes using native tree and shrub species, termed envi­ron­men­tal plant­i­ngs, has been rec­og­nized as a car­bon off­set method­ol­ogy which can con­tribute to bio­di­ver­sity con­ser­va­tion as well as cli­mate mit­i­ga­tion. How­ever, far less atten­tion has been paid to the poten­tial for assisted nat­ural regen­er­a­tion in areas of low to inter­me­di­ate lev­els of degra­da­tion, where regen­er­a­tive capac­ity still remains and lit­tle inter­ven­tion would be required to restore native veg­e­ta­tion. In this study, we con­sid­ered the eco­nom­ics of car­bon farm­ing in the state of Queens­land, Aus­tralia, where 30.6 mil­lion hectares of rel­a­tively recently defor­ested agri­cul­tural land­scapes may be suit­able for car­bon farm­ing. Using spa­tially explicit esti­mates of the rate of car­bon seques­tra­tion and the oppor­tu­nity cost of agri­cul­tural pro­duc­tion, we used a dis­counted cash flow analy­sis to exam­ine the eco­nomic via­bil­ity of assisted nat­ural regen­er­a­tion rel­a­tive to envi­ron­men­tal plant­i­ngs. We found that the aver­age min­i­mum car­bon price required to make assisted nat­ural regen­er­a­tion viable was 60% lower than what was required to make envi­ron­men­tal plant­i­ngs viable ($65.8 t CO₂e⁻¹ com­pared to $108.8 t CO₂e⁻¹). Assisted nat­ural regen­er­a­tion could sequester 1.6 to 2.2 times the amount of car­bon pos­si­ble com­pared to envi­ron­men­tal plant­i­ngs alone over a range of hypo­thet­i­cal car­bon prices and assum­ing a mod­er­ate 5% dis­count rate. Using a com­bi­na­tion of method­olo­gies, car­bon farm­ing was a viable land use in over 2.3% of our study extent with a low $5 t CO₂e⁻¹ car­bon price, and up to 10.5 mil­lion hectares (34%) with a car­bon price of $50 t CO₂e⁻¹. Car­bon seques­tra­tion sup­ply and eco­nomic returns gen­er­ated by assisted nat­ural regen­er­a­tion were rel­a­tively robust to vari­a­tion in estab­lish­ment costs and dis­count rates due to the uti­liza­tion of low-cost tech­niques to reestab­lish native veg­e­ta­tion. Our study high­lights the poten­tial util­ity of assisted nat­ural regen­er­a­tion as a refor­esta­tion approach which can cost-effectively deliver both car­bon and bio­di­ver­sity benefits.