Carbon model assessments and improvements

Project Description

This project has 3 key goals:

1) Assess modeling approaches to quantify forest ecosystem and harvested wood product carbon pools and fluxes response to different management practices and climate change.

2) Assess modeling approaches for different uses of harvested wood products and effects on carbon stores, energy and material substitution, and leakage of harvest impacts.

3) Assess methods to incorporate effects of climate change and natural disturbance regimes on ecosystem carbon balance and land cover types.

Purpose and Scope

The purpose of this project is to assist managers and policymakers in selecting and running projection models to assess the impact of alternative management approaches on ecosystem and harvested wood products carbon stocks and emissions.

Image: Flows of carbon from the atmosphere to the forest and back. Carbon is stored mostly in live and dead wood as forests grow. From Ryan et al. (2010).

Methods

First we will describe the conceptual frameworks, mechanisms, and data requirements for different types of models so that partners can make informed decisions about which models to use and why, as well as identify gaps in current modeling capabilities. Our approach will focus on a literature review of models identified by partners and scientists to describe the key attributes of model inputs, outputs, and primary mechanisms. The work of the carbon science synthesis project will be key to understanding which relationships being modeled are robust and which are more conjectural. This step should lead to a specific plan for pairing models with research questions, the dependencies between them, and the desired outputs.

Image: Schematic showing the flow of calculations to quantify harvested wood products in use, products in disposal sites, and emissions with and without energy capture. From Stockmann et al. (2012).

The next step is configuring and running the selected models, conducting surveys, and/or compiling existing datasets. While some models can easily encompass the entire region, others will focus on specific populations or subregions due to limited data or capacity. An initial comparison of ecosystem models for a pilot study area would assess the ability of different models to represent systems at different scales and timeframes. This would be facilitated by sending personnel to in-depth training sessions. Validation could consist of comparing results to empirical data where available.

Projecting ecosystem carbon stock and flux in responses to management, disturbance, and climate will apply the models developed to run simulations and imputations to account for differences in vegetation type and management goals for different landscape positions (e.g., riparian vs. upland). To address pools and flow of harvested wood products for West Coast states and estimate potential “substitution” benefits of using wood instead of other manufactured products, we will incorporate current harvest and manufacturing practices into the modeling framework, and model future pools and flows using removals derived from the projections.

Improving and addressing uncertainties in soil carbon models will involve examining soil properties (mineralogy, chemistry, physical properties, and depth to influence soil carbon storage and loss) along the latitudinal gradient of coastal rainforest; how soil types influence carbon composition and stabilization; and how mineral sorption and hydrologic transport regulate lateral export of carbon and solutes from forested soils.