Global warming implications from increased forest biomass utilization for bioenergy in a supply-constrained context

Area of Science:

• Forestry science
• Climate change mitigation
• Bioenergy production

Background:

• Increasing demand for biomass for bioenergy necessitates analysis of forest management impacts.
• Maritime pine forest plantations in Portugal are a key case study for biomass sourcing.
• Global warming implications of different forest management strategies require urgent assessment.

Purpose of the Study:

• To analyze forest management strategies for bioenergy biomass supply.
• To assess the global warming implications of these strategies in Portugal.
• To inform national forest and energy policies for environmental benefits.

Main Methods:

• Parametric stand-level C-flux model adapted to Portuguese conditions.
• Dynamic CO2 inventory and landscape-level extension coupled with a climate model.
• Calculation of time-adjusted absolute global warming potential (AGWP) for various scenarios.

Main Results:

• Sustainable and proactive management (SMART) and expansion (EXP) show long-term global warming mitigation benefits (GWPbio < 0).
• Full residue harvest (FULL) and biomass import (IMP) offer fast supply but limited to null AGWP reduction (0 < GWPbio < 1) with associated risks.
• SMART and EXP strategies have a slow supply response, while FULL and IMP have a fast response.

Conclusions:

• SMART and EXP strategies are effective for long-term climate mitigation in supply-constrained regions.
• FULL and IMP strategies provide short-term biomass supply but require careful risk management and policy consideration.
• National policies must be revised to balance short-term bioenergy needs with long-term environmental sustainability.