Forest fertilization

Canada contains 401 million hectares of forest and woodland with 64 million hectares in British Columbia.  On Dec 17th 2002 Canada ratified the Kyoto Protocol requiring it to reduce emissions to 6% below 1990 levels between 2008-2012. This treaty has generated interest in the role of forest management as a potential tool to reduce net greenhouse emissions.

Forest fertilization is used by industries to increase timber yield however, the potential of sequestering carbon dioxide from the atmosphere through more rapid photosynthesis and primary production has not been researched.  The consequences of fertilization on soil organic matter dynamics and greenhouse gas emission of nitrous oxide (N2O) and consumption of methane (CH4) are largely unknown and must be considered.

A study is underway in BC lodgepole pine, coastal western hemlock and Douglas-fir plantations, three economically important types of forests that routinely undergo operational fertilization with Nitrogen or a fertilizer mix of Nitrogen, Phosphorous, and micronutrients.

The first objective of this study is to quantify the amount of additional carbon (C) sequestered in tree biomass and soil when forests are fertilized.  We hypothesize that nitrogen (N) or nutrient additions influence tree growth and carbon mineralization rates and hence increase the carbon sink strength of Canadian forests.

Our second objective is to characterize the potential negative side effects of fertilization, focusing on microbial community structure and function responsible for the emissions of N2O and oxidation of CH4.

The last goal of the project is to use an ecosystem model to scale findings up to relevant management areas and use a life-cycle modeling approach to estimate the economic viability of forest fertilization as a strategy to reduce the net greenhouse gas burden of commercial forestry industries and potentially generate Kyoto Protocol offset credits.

This project is funded through NSERC Strategic.

Investigators

Sue Grayston (Forest Sciences, UBC)
Cindy Prescott (Forest Sciences, UBC)
Gary Bull (Forest Sciences, UBC)
Gordon Weetman (Forest Sciences, UBC)
Rob Seely
Bill Mohn (Microbiology & Immunology, UBC)

Graduate Students

Veneta Yolova MSc
Amer Khan MSc
Steven Northway PhD

Collaborators

Real Roy (University of Victoria)
Paul Sanborn (UNBC)
Rob Brockley (BC MoFR)
Nate Basiliko (University of Toronto at Mississauga)