National Greenhouse Gas Inventory

Greenhouse gas inventory at the national level includes estimation of emissions and removals of GHGs in agriculture, forest land, grassland and other land-use categories. The key GHGs of concern for land-use sectors are CO2, nitrous oxide (N2O) and methane (CH4). Of these, CO2 is the dominant GHG, and CO2 fluxes between the atmosphere and the land are primarily controlled by uptake for plant growth and releases from respiration, decomposition and oxidation of organic matter. Emissions and removals for a given land-use category or subcategory are estimated by using the area under the category or subcategory and changes in stocks of different carbon pools.

Annual change in carbon stock (tC/ha) = Sum of annual changes in different carbon pools (AGB + BGB + DW + LT + SC)

where, C is carbon, AGB is above-ground biomass, BGB is below-ground biomass, DW is deadwood, LT is litter and SC is soil organic carbon.

Preparing a carbon inventory for the national GHG inventory for a given land-use category such as forest land, grassland or cropland involves two approaches (IPCC 1996, 2006):

• Carbon "Stock-Difference" method, which requires estimation of stocks of different carbon pools over two periods

• Carbon "Gain-Loss" method, which requires estimation of annual gains and losses in carbon stocks

The key steps in estimation of carbon inventory for national GHG inventory are as follows:

Step 1: Estimate the area under a given land-use category and subcategory in a given year as well as area under each land-use category subjected to land-use change

Step 2: Estimate the stocks of carbon in each of the carbon pools at the beginning and end of the period, the difference between the two periods being the net emission or removal

Step 3: Alternatively, estimate the gain in carbon stock for each of the carbon pools due to growth or accumulation and losses from each pool due to harvest and disturbance. Next, estimate the difference between carbon gain and losses as the net emission or removal.

Methods for carbon inventory in forest land, cropland, grassland and other land-use categories include those for estimating the following quantities:

• Area and area changes under each land-use category and subcategory

• Carbon accumulation in above-ground and below-ground biomass or stock changes in biomass pools over time

• Changes in stocks of litter and deadwood or flows into and out of these pools

• Changes in soil organic carbon stock or rate of accumulation

• Losses in carbon held in biomass and in soil due to harvest and disturbance

Table 3.1 Carbon inventory categories for national greenhouse gas inventory according to IPCC (1996) and IPCC (2006)_

IPCC 1996

IPCC 2006

5A: Changes in forest and other

Forest land

woody biomass stocks

(a) Forest land remaining forest land

(b) Land converted to forest land

5B: Forest and grassland conversion


(a) Cropland remaining cropland

(b) Land converted to cropland

5C: Abandonment of croplands, pastures,


plantation forests, or other managed lands

(a) Grassland remaining grassland

(b) Land converted to grassland

5D: CO2 emissions and removals from soils


(a) Wetland remaining wetland

(b) Land converted to wetland


(a) Settlement remaining settlement

(b) Land converted to settlement

A carbon inventory, as part of estimating national GHG emissions and removals, has to be prepared and reported by Annex-I or industrialized countries and the non-Annex-I or developing countries. IPCC (1996, 2006) provides guidelines for preparing such an inventory for different land-use categories (Table 3.1), and this handbook supplements those guidelines with details and step-by-step procedures and describes, in Chapter 16, how the guidelines can be applied to preparing a national GHG inventory.

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

Get My Free Ebook

Post a comment