Overview
This project aimed to identify the potential of various management practices to decrease the immediate and rapid soil carbon loss during land clearing and for management activities for farming immediately following clearing.
The team did a literature review and meta-analysis (analysis of findings across multiple published studies), along with a visit to Indonesia, to synthesise existing research on the amounts and types of greenhouse gas emissions that arise when peatlands are converted into agricultural land. Clearing of peat for agriculture is no longer permitted, and thus the measurement of emissions from that conversion process is no longer highly relevant to policy or management. Fortunately, the team used a research approach that allowed them to also understand the implications of land abandonment and management.
Once peat has been converted to agricultural land, it often degrades to the point of land abandonment. Abandoned agricultural lands emit more greenhouse gases than actively managed lands, in part because of increasing fire risks. Thus, supporting people to manage lands well enough to prevent abandonment would avoid greenhouse gas emissions as well as sustain livelihoods.
One of the biggest reasons why converted peat emits greenhouse gases is because water tables are lowered too far. Maintaining higher water tables as well as reducing nitrogen fertiliser inputs are the most significant ways to ensure that greenhouse gas emissions are minimised from agricultural lands that were once peatlands.
Finally, an important result is that different activities may raise or lower different types of greenhouse gases. For example, an activity could increase carbon dioxide emissions but still have a net effect of decreasing overall greenhouse gas emissions, and thus be more beneficial than suspected based on a simpler analysis. Therefore, understanding the contribution of land management to overall emissions requires a comprehensive evaluation approach.
