Sustainable Watersheds for Carbon Offsets: Biomass harvesting for phosphorus capture, habitat renewal and carbon emissions reductions

This review examines the benefits of applying biomass to land to improve soil health and examines current global carbon markets and initiatives since the Kyoto Protocol (1997) and the Paris Agreement (2015) to provide lessons from global carbon markets for Canada and Manitoba. We assess applicable carbon market verification methodologies to identify those that could be considered and modified for ongoing and future bioeconomy initiatives.

Here at IISD, we have pioneered innovative watershed management practices by harvesting cattails and other plants from marginal agricultural land, water retention sites and roadside drainage ditches to remove nutrients taken up by those plants. The abundant plant biomass can then be used for energy, bedding, compost and soil enhancement to generate carbon offsets from carbon dioxide displacement and sequestration.

This matters because the use of waste material is the foundation of the bioeconomy—where biological waste resources are converted into value-added products—and is at the core of the ‘circular economy,’ whereby resources are maintained in the economy for as long as possible to reduce waste.

Using ‘unconventional’ waste biomass also has other added benefits, which raises its environmental profile. Harvesting removes captured phosphorus before it gets into lakes, such as Lake Winnipeg, to be recovered and used as agricultural fertilizer. Removal of biomass also improves habitat health and biodiversity, improves flow to reduce flood impacts and helps control invasive species.