Forest landscape restoration (FLR) has been adopted by governments and practitioners across the globe to mitigate and adapt to climate change and restore ecological functions across degraded landscapes. However, the extent to which these activities capture CO2 with associated climate mitigation impacts are poorly known, especially in geographies where data on biomass growth of restored forests are limited or do not exist. To fill this gap, we developed biomass accumulation rates for a set of FLR activities (natural regeneration, planted forests and woodlots, agroforestry, and mangrove restoration) across the globe and global CO2 removal rates with corresponding confidence intervals, grouped by FLR activity and region/climate.

BACKGROUND:The degradation of forests in developing countries, particularly those within tropical and subtropical latitudes, is perceived to be an important contributor to global greenhouse gas emissions. However, the impacts of forest degradation are understudied and poorly understood, largely because international emission reduction programs have focused on deforestation, which is easier to detect and thus more readily monitored. To better understand and seize opportunities for addressing climate change it will be essential to improve knowledge of greenhouse gas emissions from forest degradation.RESULTS:Here we provide a consistent estimation of forest degradation emissions between 2005 and 2010 across 74 developing countries covering 2.2 billion hectares of forests. We estimated annual emissions of 2.1 billion tons of carbon dioxide, of which 53% were derived from timber harvest, 30% from woodfuel harvest and 17% from forest fire. These percentages differed by region: timber harvest was as high as 69% in South and Central America and just 31% in Africa; woodfuel harvest was 35% in Asia, and just 10% in South and Central America; and fire ranged from 33% in Africa to only 5% in Asia. Of the total emissions from deforestation and forest degradation, forest degradation accounted for 25%. In 28 of the 74 countries, emissions from forest degradation exceeded those from deforestation.CONCLUSIONS:The results of this study clearly demonstrate the importance of accounting greenhouse gases from forest degradation by human activities. The scale of emissions presented indicates that the exclusion of forest degradation from national and international GHG accounting is distorting. This work helps identify where emissions are likely significant, but policy developments are needed to guide when and how accounting should be undertaken. Furthermore, ongoing research is needed to create and enhance cost-effective accounting approaches.

In light of the devastating loss of forest cover, biodiversity, and ecosystem services in the Atlantic Forest of Brazil, people are endeavoring to restore this fragmented forest system. The afforestation of abandoned or degraded land is a practical approach to restore regional ecological functions and to sequester atmospheric carbon to help mitigate the global imbalance of atmospheric carbon associated with climate change. Large gaps, however, remain in understanding the dynamics of afforested tree communities. In this study, the effect of topographical relief and soil properties on growth performance of planted trees has been assessed. Above ground dry biomass (AGB(dry)) accumulation was estimated to evaluate the performance of afforested tree communities on formerly abandoned pastures at the Reserva Ecologica de Guapiacu, Rio de Janeiro, Brazil. The study revealed large discrepancies in AGBdry and respective organic carbon accumulationThe afforested tree community located on the sloped terrain stored only half the carbon (21.70 +/- 7.3 Mgha(-1)) that the planted trees on the flat terrain stored. (46.67 +/- 8.7 Mgha(-1)). Our results suggest that differences in tree growth performance are complex, depending largely on topography and related soil conditions. These circumstances should be considered to prevent misleading carbon sink estimates when developing regional strategies for Reducing Emissions from Deforestation and Degradation (REDD+) that promote afforestation activities. (C) 2014 Elsevier B.V. All rights reserved.