The cost of restoring carbon stocks in Brazil's Atlantic Forest

Abstract

Knowing which restoration approach provides the best returns on investment for accumulating carbon is essential to foster restoration planning, financing, and implementation. Here, we explored the cost‐effectiveness and drivers of aboveground and soil carbon accumulation in restored forests across an agricultural landscape of Brazil's Atlantic Forest. The recovery of aboveground and soil carbon stocks, as well as the implementation and land opportunity costs, was assessed across chronosequences (10–60 years) of second‐growth forests and mixed‐species tree plantings and old growth, reference forest remnants. Plantations accumulated approximately 50% more aboveground carbon than second‐growth forests throughout the chronosequence. When controlling for soil clay content, soil carbon stocks were higher in reference than in restored forests, but they were comparable between plantations and second‐growth forests. After 60 years of stand development, recovery of total carbon stocks in both restoration approaches reached only half of the average stocks of reference forests. Total cost‐effectiveness for carbon accumulation, including both implementation and land opportunity costs, was on average 60% higher for second‐growth forests than for plantations (15.1 and 9.4 kgC US$−1, respectively). Although tree plantations initially showed higher rates of carbon storage than second‐growth forests, their higher implementation and land opportunity costs make them less cost‐effective for carbon farming. Our results further suggest that, at current pricing levels, carbon markets alone have a limited potential to up‐scale restoration efforts in Brazil's Atlantic Forest.

A practice-led assessment of landscape restoration potential in a biodiversity hotspot

“…Contrary to findings based on shorter-time frame studies [25,94], we found that sites restored through planting accumulated more AGB over time when compared to less severely degraded areas subjected to passive regeneration and ANR, and that these gains outweighed initially high implementation costs, thus increasing cost-effectiveness overall. Similarly, irrespective of the method employed, we demonstrate that overall cost-effectiveness increases with investment duration [29], by 95.1 times in our region, underscoring the need for long-term funding of restoration projects [64]. Similarly, investment size in terms of the contiguous land area restored can impact on cost-effectiveness, with potential 57% cost reductions as a result of increasing the size of restoration areas from one to 100 hectares [100].…”

“…Furthermore, while our AGB modelling projections appear intuitive, there is also potential for future experimentation. We did not account for variation in AGB accumulation rate as a result of restoration method [29], climate [92], topography [93], local site conditions (e.g. soil type, [49] and, former land use, [8]), or landscape features (e.g.…”

“…By contrast, it can take 10 to 80 years to restore species composition [26,27] and 15 to greater than 1000 years to restore biomass [28]. In terms of opportunity costs, land rental, market prices for local produce, and population density are commonly used as proxies [25,29], but this fails to incorporate the full range of costs that restoration imposes on local people and on projects aiming to offset these. Thus, more complete, location-specific assessments of costs are needed to support restoration prioritization and decision-making that maximizes sustained social and ecological outcomes per unit investment [30].…”

System Dynamics Modeling to Compensate Co 2 Emissions in Road and Road-rail Transport Models in the Atlantic Forest Biome

“…Regarding the mitigation of GHG emissions, the forest appears as an important alternative, which is why compensatory plantings are carried out around the world in REDD + projects and also by free initiative of private companies, especially in Brazil. Among these practices, the Atlantic Forest restoration planting stands out, which, according to Brancalion et al (2021), proved to be more e cient in carbon storage than natural regeneration during the rst 50 years, being a technique widely used not only for this reason, but also because it is suitable for places of low socio-ecological resilience.…”