Biomass & carbon - pyFIA

Biomass queries apply species-specific wood and bark properties (specific gravity, moisture content, bark volume) to convert tree measurements into dry or green weight.

Colorado — above-ground dry biomass by species group

EVALID: 82101 (Colorado 2021) · Result: 1.096 billion tons across 10 species groups (spruce 26.4%, aspen 22.6%) · source

Uses DRYBIO_AG with a species-specific green-to-dry conversion, grouped by SPGRPCD.

View SQL

SELECT
    SPGRPCD,
    species_group_name,
    SUM(ESTIMATED_VALUE * EXPNS) AS total_biomass_tons
FROM (
    SELECT
        pop_stratum.EXPNS,
        REF_SPECIES_GROUP_TREE.SPGRPCD,
        REF_SPECIES_GROUP_TREE.NAME AS species_group_name,
        SUM(
            TREE.TPA_UNADJ *
            COALESCE(
                (
                    (1 - (REF_SPECIES.BARK_VOL_PCT / (100 + REF_SPECIES.BARK_VOL_PCT))) *
                    REF_SPECIES.WOOD_SPGR_GREENVOL_DRYWT /
                    (
                        (1 - (REF_SPECIES.BARK_VOL_PCT / (100 + REF_SPECIES.BARK_VOL_PCT))) *
                        REF_SPECIES.WOOD_SPGR_GREENVOL_DRYWT +
                        (REF_SPECIES.BARK_VOL_PCT / (100 + REF_SPECIES.BARK_VOL_PCT)) *
                        REF_SPECIES.BARK_SPGR_GREENVOL_DRYWT
                    ) *
                    (1.0 + REF_SPECIES.MC_PCT_GREEN_WOOD * 0.01) +
                    (REF_SPECIES.BARK_VOL_PCT / (100 + REF_SPECIES.BARK_VOL_PCT)) *
                    REF_SPECIES.BARK_SPGR_GREENVOL_DRYWT /
                    (
                        (1 - (REF_SPECIES.BARK_VOL_PCT / (100 + REF_SPECIES.BARK_VOL_PCT))) *
                        REF_SPECIES.WOOD_SPGR_GREENVOL_DRYWT +
                        (REF_SPECIES.BARK_VOL_PCT / (100 + REF_SPECIES.BARK_VOL_PCT)) *
                        REF_SPECIES.BARK_SPGR_GREENVOL_DRYWT
                    ) *
                    (1.0 + REF_SPECIES.MC_PCT_GREEN_BARK * 0.01)
                ),
                1.76  -- Default specific gravity when species data unavailable
            ) *
            CASE
                WHEN TREE.DIA IS NULL THEN POP_STRATUM.ADJ_FACTOR_SUBP
                ELSE
                    CASE LEAST(TREE.DIA, 5 - 0.001)
                        WHEN TREE.DIA THEN POP_STRATUM.ADJ_FACTOR_MICR
                        ELSE
                            CASE LEAST(TREE.DIA, COALESCE(CAST(PLOT.MACRO_BREAKPOINT_DIA AS DECIMAL), 9999) - 0.001)
                                WHEN TREE.DIA THEN POP_STRATUM.ADJ_FACTOR_SUBP
                                ELSE POP_STRATUM.ADJ_FACTOR_MACR
                            END
                    END
            END *
            COALESCE(TREE.DRYBIO_AG / 2000, 0)  -- pounds to tons
        ) AS ESTIMATED_VALUE
    FROM POP_STRATUM
    JOIN POP_PLOT_STRATUM_ASSGN ON (POP_PLOT_STRATUM_ASSGN.STRATUM_CN = POP_STRATUM.CN)
    JOIN PLOT ON (POP_PLOT_STRATUM_ASSGN.PLT_CN = PLOT.CN)
    JOIN COND ON (COND.PLT_CN = PLOT.CN)
    JOIN TREE ON (TREE.PLT_CN = COND.PLT_CN AND TREE.CONDID = COND.CONDID)
    JOIN REF_SPECIES ON (TREE.SPCD = REF_SPECIES.SPCD)
    LEFT OUTER JOIN REF_SPECIES_GROUP REF_SPECIES_GROUP_TREE ON (
        REF_SPECIES_GROUP_TREE.SPGRPCD = CASE
            WHEN TREE.STATECD IN (46, 38, 31, 20) AND TREE.SPCD = 122 THEN 11
            ELSE TREE.SPGRPCD
        END
    )
    WHERE
        TREE.STATUSCD = 1
        AND COND.COND_STATUS_CD = 1
        AND pop_stratum.RSCD = 22 AND pop_stratum.EVALID = 82101  -- Colorado 2021
    GROUP BY
        pop_stratum.ESTN_UNIT_CN, pop_stratum.CN, plot.CN, plot.PREV_PLT_CN,
        cond.CN, plot.LAT, plot.LON, pop_stratum.EXPNS,
        REF_SPECIES_GROUP_TREE.SPGRPCD, REF_SPECIES_GROUP_TREE.NAME
)
GROUP BY SPGRPCD, species_group_name
ORDER BY total_biomass_tons DESC;

North Carolina — merchantable bole biomass

EVALID: 372301 (North Carolina 2023) · Result: 1.56 billion green short tons (live timber species ≥5” DBH), by diameter class and species · source

Sums the merchantable bole (DRYBIO_BOLE + DRYBIO_BOLE_BARK) on a green-weight basis, broken out by diameter class and species. See the source file for the full diameter-class formatting.

The Python equivalent is biomass(), which returns biomass and carbon columns and applies the carbon fraction for you.