Growing our future: Assessing the outcome of afforestation programs in Ontario, Canada

The United Nations Framework Convention on Climate Change (UNFCCC) requires its signatories, including Canada, to estimate and report their annual greenhouse gas (GHG) emissions and removals. Forests are an important natural resource as they slow the accumulation of atmospheric carbon through the process of carbon sequestration. Due to the role of forests as carbon sinks, governments consider afforestation projects as feasible climate change mitigation strategies. This article outlines a spatially-explicit approach to validating afforestation data in Ontario, Canada. Validation is a user-supervised process that uses satellite imagery, remote sensing tools, and other auxiliary data to confirm the presence of seedlings planted through Forests Ontario’s 50 Million Tree program. Of the 12 466 hectares assessed, 83% is identified as afforested, 6% is not afforested and 10% is not determined. The area classified as successful afforestation is used as input for the Generic Carbon Budget Model (GCBM), to simulate afforestation effects on carbon stocks. Our findings show the afforestation activities will create a small carbon sink by 2060. From this project, it is evident that spatial validation of afforestation data is feasible, although the collection of additional standardized auxiliary data is recommended for future afforestation projects, if carbon benefits are to be reported.