Declining conifer productivity will drive future forest dynamics as climate changes in northern New England

Area of Science:

• Forestry and climate change impacts on temperate forest ecosystems.
• Ecological modeling for predicting forest dynamics under climate change scenarios.
• Sustainable forest management and natural climate solutions.

Background:

• Temperate forests in New England face declining habitat suitability for conifers due to climate change.
• Understanding forest transition dynamics is crucial for commercial forestry and carbon sequestration.
• Existing forest management practices may not be resilient to future climate conditions.

Purpose of the Study:

• To simulate the effects of climate change and timber harvesting on New England forests.
• To assess the impacts on live, aboveground biomass and carbon sequestration potential.
• To evaluate adaptation strategies at a scale relevant to forest management.

Main Methods:

• Utilized the LANDIS-II forest landscape model to simulate climate change under RCP 4.5 and 8.5.
• Incorporated interactions with timber harvesting under a predominant harvest regime in Maine.
• Analyzed changes in species' net primary productivity and establishment probability on biomass trends (2010-2100).

Main Results:

• Climate change negatively impacts area-wide forest biomass, primarily due to declining conifer productivity.
• Conifers like balsam fir and red spruce are projected to remain productive but face declining establishment.
• Regional harvest supply may be maintained short-term, but current practices risk unsustainability as conifer productivity decreases.

Conclusions:

• New England forests will likely remain an aboveground carbon sink this century.
• Adaptive management is essential to enhance forest resistance and resilience to climate change.
• Without adaptation, the forest's carbon sequestration capacity is projected to diminish.