Growth and Mortality Queries¶

This directory contains SQL queries for estimating forest growth, mortality, and removals using FIA data.

Available Queries¶

Mortality Queries¶

• Colorado Merchantable Volume Mortality - Annual mortality of merchantable bole wood volume of growing-stock trees
• North Carolina Tree Mortality Rate - Simple mortality rate in trees per acre per year on forest land
• Georgia Growing-Stock Mortality by Damage Agent - Annual mortality by tree-level cause of death and species
• Georgia Growing-Stock Mortality by Disturbance Type - Annual mortality by condition-level disturbance and species

Key Concepts¶

Growth/Removal/Mortality (GRM) Evaluations¶

Unlike volume or area estimates, growth and mortality calculations require special evaluation types:

• GRM Evaluations: Use remeasurement data from plots visited multiple times
• TREE_GRM Tables: Contain component-based calculations for growth, mortality, and removals
• Annual Rates: Values are already annualized based on remeasurement period

Important Tables¶

• TREE_GRM_BEGIN: Tree attributes at start of remeasurement period
• TREE_GRM_COMPONENT: Pre-calculated annual rates by component type
• TREE_GRM_MIDPT: Tree attributes at midpoint (for growth calculations)

Component Types¶

• MORTALITY1, MORTALITY2: Different mortality events
• SURVIVOR: Trees that survived the remeasurement period
• INGROWTH: New trees entering the inventory
• REMOVAL1, REMOVAL2: Harvest or other removals

Tree Classifications¶

• All Live (AL): All live trees regardless of merchantability
• Growing Stock (GS): Merchantable timber trees only

Query Patterns¶

Basic Mortality Query Structure¶

SELECT
    SUM(
        tgc.SUBP_COMPONENT_GS_FOREST * t.VOLCFNET *
        [adjustment_factors] * ps.EXPNS
    ) as annual_mortality
FROM POP_STRATUM ps
JOIN [standard FIA joins]
JOIN TREE_GRM_COMPONENT tgc ON tgc.PLT_CN = p.CN
JOIN TREE_GRM_BEGIN t ON t.TRE_CN = tgc.TRE_CN
WHERE
    tgc.COMPONENT LIKE 'MORTALITY%'
    AND [other filters]

Coming Soon¶

• Growth rate queries
• Removals (harvest) estimation
• Net change calculations
• Mortality by cause
• Growth by species group