GHG Inventory
Emissions, removals, activity data, emission factors and uncertainty.
Emission Factors
Carbon stocks per hectare for each stratum and canopy class are the basis of every emission factor. They come from 121 pilot inventory plots (ICFRA 2016, JICA CADEP-SFM 2017), converted with the allometric equations, root:shoot ratios and carbon fraction below.
| Stratum | Canopy | AGB t/ha | BGB t/ha | Biomass t/ha | Carbon t/ha | CO₂ t/ha |
|---|---|---|---|---|---|---|
| Montane & western rain forests | Dense | 244.8 | 90.57 | 335.37 | 157.62 | 577.95 |
| Montane & western rain forests | Moderate | 58.43 | 21.62 | 80.05 | 37.62 | 137.96 |
| Montane & western rain forests | Open | 18.31 | 6.77 | 25.08 | 11.79 | 43.23 |
| Mangroves & coastal forests | Dense | 94.63 | 18.93 | 113.55 | 53.37 | 195.69 |
| Mangroves & coastal forests | Moderate | 52.75 | 10.55 | 63.3 | 29.75 | 109.08 |
| Mangroves & coastal forests | Open | 24.01 | 4.8 | 28.81 | 13.54 | 49.64 |
| Dryland forests | Dense | 42.43 | 11.88 | 54.31 | 25.53 | 93.6 |
| Dryland forests | Moderate | 34.52 | 9.67 | 44.19 | 20.77 | 76.15 |
| Dryland forests | Open | 14.26 | 3.99 | 18.26 | 8.58 | 31.47 |
| Plantation forest | — | 324.79 | 87.69 | 412.48 | 193.87 | 710.84 |
| Grassland | — | — | — | 8.7 | 4.09 | 14.99 |
| Cropland, wetland, settlement & other | — | 0 | 0 | 0 | 0 | 0 |
Emission factors (EF) are the change in CO₂ per hectare between two land classes. Because no full NFI had been completed by 2020, Kenya used country-specific data from the pilot forest inventories of IC-FRA (KFS, 2016) and CADEP-SFM (JICA, 2017).
- Above-ground biomass (AGB) from allometric equations; below-ground biomass (BGB) = AGB × root:shoot ratio
- Carbon stock (tC/ha) = (AGB + BGB) × 0.47 (carbon fraction, IPCC 2006)
- CO₂ (tCO₂/ha) = carbon stock × 44/12
- EF = CO₂ at the start class − CO₂ at the end class
| Type | Volume (m3) | Reference | Equation for AGB (kg) | Reference |
|---|---|---|---|---|
| Common for natural forests and plantations | π×(DBH/200)2×H×0.5 | Henry et al. 2011 | 0.0673(0.598D2H)0.976 | Chave et al. 2009, 2014 |
| Rhizophora sp. in mangroves | π×(DBH/200)2×H×0.5 | Henry et al. 2011 | 0.128×DBH2.60 | Fromard et al. 1998, Komiyama et al. 2008 |
| Bamboo in montane forests | d2-(d0.7)2/4πh0.8 | Dan et al. 2007 | 1.04+0.06dGWbamboo GWbamboo=1.11+0.36d2 (bamboo diameter > 3 cm) GWbamboo=1.11+0.363.12 (bamboo diameter ≤ 3 cm) | Muchiri and Muga. 2013 |
| Climbers in natural forests | - | - | e(-1.484+2.657ln(DBH)) | Schnitzer et al. 2006 |
| Forest stratum | Root:shoot ratio | Source (IPCC 2006 Guidelines, Vol. 4, Table 4.4) |
|---|---|---|
| Montane & western rain forests & bamboo | 0.37 | Tropical rainforest |
| Dryland forests | 0.28 | Tropical dry forest, above-ground biomass > 20 t/ha |
| Mangroves & coastal forests | 0.20 | Tropical moist deciduous forest, above-ground biomass < 125 t/ha |
| Plantation forest land | 0.27 | Tropical mountain systems |
| Class | CO2 Amount(t/ha) | References |
|---|---|---|
| Cropland | 0 | IPCC Guideline 2006 |
| Grassland | 14.99 | IPCC Guideline 2006 |
| Wetland | 0 | IPCC Guideline 2006 |
| Settlement and Other land | 0 | IPCC Guideline 2006 |
| Start \ end | MW-D | MW-M | MW-O | MC-D | MC-M | MC-O | DL-D | DL-M | DL-O | Plantation | Cropland | Grassland | Wetland | Settlement & other |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Montane & WRB - Dense | 0 | 440.00 | 534.72 | 577.95 | 562.96 | 577.95 | 577.95 | |||||||
| Montane & WRB - Moderate | -29.28 | 0 | 94.73 | 137.96 | 122.96 | 137.96 | 137.96 | |||||||
| Montane & WRB - Open | -29.28 | -29.28 | 0 | 43.23 | 28.24 | 43.23 | 43.23 | |||||||
| Mangroves & coastal - Dense | 0 | 86.61 | 146.04 | 195.69 | 180.69 | 195.69 | 195.69 | |||||||
| Mangroves & coastal - Moderate | -10.75 | 0 | 59.44 | 109.08 | 94.09 | 109.08 | 109.08 | |||||||
| Mangroves & coastal - Open | -10.75 | -10.75 | 0 | 49.64 | 34.65 | 49.64 | 49.64 | |||||||
| Dryland - Dense | 0 | 17.44 | 62.13 | 93.60 | 78.60 | 93.60 | 93.60 | |||||||
| Dryland - Moderate | -15.88 | 0 | 44.69 | 76.15 | 61.16 | 76.15 | 76.15 | |||||||
| Dryland - Open | -15.88 | -15.88 | 0 | 31.47 | 16.47 | 31.47 | 31.47 | |||||||
| Plantation | 0 | 710.84 | 695.85 | 710.84 | 710.84 | |||||||||
| Cropland | -94.44 | -94.44 | -43.23 | -41.36 | -41.36 | -41.36 | -21.18 | -21.18 | -21.18 | -87.55 | ||||
| Grassland | -79.45 | -79.45 | -28.24 | -26.37 | -26.37 | -26.37 | -6.18 | -6.18 | -6.18 | -72.55 | ||||
| Wetland | -94.44 | -94.44 | -43.23 | -41.36 | -41.36 | -41.36 | -21.18 | -21.18 | -21.18 | -87.55 | ||||
| Settlement & other land | -94.44 | -94.44 | -43.23 | -41.36 | -41.36 | -41.36 | -21.18 | -21.18 | -21.18 | -87.55 |
MW = Montane & western rain forests & bamboo; MC = Mangroves & coastal forests; DL = Dryland forests; D / M / O = Dense / Moderate / Open canopy.
Additional factors used in the national GHG inventory (NID 2024)
The inventory uses the same pilot-inventory carbon stocks per stratum and canopy class as shown above. Biomass is converted to carbon with the IPCC default carbon fraction of 0.47, and carbon to CO₂ by multiplying by 44/12. Below-ground biomass comes from these root-to-shoot ratios:
| Forest type | Root-to-shoot ratio (t root d.m. per t shoot d.m.) | IPCC 2006 reference (Vol. 4, Ch. 4, Table 4.4) |
|---|---|---|
| Montane | 0.27 | Tropical mountain systems |
| Western rain forest | 0.37 | Tropical rain forest |
| Coastal | 0.24 / 0.20 | Tropical moist deciduous forest (AGB above / below 125 t/ha) |
| Mangroves | 0.24 / 0.20 | Tropical moist deciduous forest (AGB above / below 125 t/ha) |
| Dryland | 0.28 / 0.56 | Tropical dry forest (AGB above / below 20 t/ha) |
| Plantation | 0.27 | Tropical mountain systems |
| Wooded grassland | 0.40 | Shrubland |
| Forest type | Growth, forests ≤ 20 years (t d.m./ha/yr) | Growth, forests > 20 years (t d.m./ha/yr) |
|---|---|---|
| Montane | 5 | 1.5 |
| Western rain forest | 10 | 3.1 |
| Coastal | 5 | 1.3 |
| Mangroves | 5 | 1.3 |
| Dryland | 2.4 | 1.8 |
| Plantation, montane | 10 | — |
| Plantation, western rain | 6 | — |
| Plantation, coastal | 9 | — |
| Plantation, dryland | 10 | — |
| Wooded grassland | 0.5 | — |
- Wooded grassland: IPCC default stock of 8.7 t carbon per hectare; open grassland is assumed to hold half of that (expert judgement).
- Perennial cropland: country-specific factors from a study of Grevillea agroforestry in Kenya (Owate et al., 2018); annual cropland uses IPCC defaults.
- Soils: Kenya is treated as one tropical dry climate region with high-activity clay mineral soils (Kenya is about 80% arid and semi-arid land); no organic soils.
- Wetlands, settlements and other land: IPCC defaults; land converted to these categories is assumed to hold zero carbon stock.
- Deforestation and degradation: instantaneous oxidation (all carbon lost at once); harvested wood products are not yet included.
Source: Ministry of Environment and Forestry, National Forest Monitoring System in the Republic of Kenya, Version 1 (Draft), February 2021. Chapter 5.2.2 (2), EF setting.
Source: Ministry of Environment, Climate Change and Forestry, Kenya's Third National Greenhouse Gas Inventory Document 1990–2022, December 2024 (Kenya’s national inventory report to the UNFCCC). Chapter 6.4.2, Tables 6-3 to 6-5.
Source: Ministry of Environment and Forestry, The National Forest Reference Level for REDD+ Implementation, December 2019 (Kenya’s FRL submission to the UNFCCC). Chapter 3.2, Tables 14, 17 and 18.