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Biomass and Carbon Queries

This section contains queries for calculating forest biomass and carbon storage using species-specific equations and properties.

Queries in this Section

1. Colorado Above-Ground Dry Biomass by Species Group

EVALID: 82101 (Colorado 2021) Result: 1.096 billion tons total above-ground dry biomass, 10 species groups

A comprehensive biomass calculation that demonstrates: - Species-specific wood and bark properties - Moisture content adjustments for accurate dry weight - Specific gravity calculations for wood and bark - Bark volume percentage corrections - Simplified approach that produces identical results to Oracle EVALIDator

Top Species Groups by Biomass: - 18: Engelmann and other spruces - 288,927,955 tons (26.4%) - 44: Cottonwood and aspen (West) - 247,391,052 tons (22.6%) - 12: True fir - 122,095,237 tons (11.1%) - 23: Woodland softwoods - 114,570,440 tons (10.5%)

2. North Carolina Merchantable Bole Biomass

EVALID: 372301 (North Carolina 2023) Result: 1.56 billion green short tons merchantable bole biomass

Calculates merchantable bole bark and wood biomass for timber species ≥5" DBH: - Green weight (includes moisture content) calculations - Merchantable bole components (DRYBIO_BOLE + DRYBIO_BOLE_BARK) - Results by diameter class and species - Complex moisture content conversions for wood and bark - EVALIDator-compatible formatting with species details

Key Findings: - Peak biomass in 11.0-12.9" diameter class (202.1 million tons) - Loblolly pine dominates across all size classes - 995 unique diameter class × species combinations - Demonstrates managed forest structure with concentration in pole-sized trees

Key Concepts Demonstrated

  • Species-Specific Calculations: Each species has unique wood and bark properties
  • Moisture Content Adjustments: Separate adjustments for wood and bark moisture
  • Specific Gravity Applications: Converting volume to weight using species properties
  • Bark Volume Corrections: Accounting for bark proportion in total tree volume
  • Unit Conversions: Converting from pounds to tons (/2000)
  • Query Simplification: Readable approach maintaining statistical accuracy

EVALIDator Methodology

These queries follow Oracle EVALIDator biomass methodology: - Uses DRYBIO_AG (above-ground dry biomass) as base measurement - Applies complex species-specific conversion factors - Includes moisture content adjustments (MC_PCT_GREEN_WOOD, MC_PCT_GREEN_BARK) - Uses specific gravity values (WOOD_SPGR_GREENVOL_DRYWT, BARK_SPGR_GREENVOL_DRYWT) - Handles bark volume percentages (BARK_VOL_PCT) for accurate wood/bark ratios - Applies diameter-based adjustment factors with nested CASE logic

Advanced Features

  • Special Species Mapping: Eastern redcedar (SPCD 122) mapped to different species groups by state
  • Default Values: Uses 1.76 specific gravity when species data unavailable
  • Complex Calculations: Multi-step biomass equations matching Oracle formulas exactly
  • Verification: Simplified version tested to produce identical results to complex Oracle translation

Usage Notes

  • Biomass calculations are computationally intensive due to species-specific formulas
  • Results represent dry weight biomass (moisture removed)
  • Carbon content typically estimated as ~50% of dry biomass
  • Query demonstrates balance between accuracy and maintainability