GHG Emissions from the AFOLU Sector

This sector deals with emissions from agricultural practices, land use changes, and forestry activities.

3A - Livestock

• 3A1 - Enteric Fermentation - Methane emissions from livestock digestion processes.
• 3A2 - Manure Management - Methane and nitrous oxide emissions from manure storage and treatment.

3B - Land

• 3B1 - Forest Land - Carbon stock changes and emissions/removals in forest lands.
• 3B2 - Cropland - Carbon stock changes and emissions/removals in cropland.
• 3B3 - Grassland - Carbon stock changes and emissions/removals in grasslands.
• 3B4 - Wetlands - Carbon stock changes and emissions/removals in wetlands.
• 3B5 - Settlements Remaining Settlements - Emissions from infrastructure and land management in settlements.
• 3B6 - Other Land - Carbon stock changes and emissions/removals in lands not covered by other categories.

3C - Aggregate Sources and Non-CO2 Emissions Sources on Land

• 3C1 - Biomass Burning - Emissions from the burning of biomass.
• 3C2 - Liming - CO2 emissions resulting from the application of lime to soils.
• 3C3 - Urea Application - CO2 emissions resulting from the application of urea to soils.
• 3C4 - Direct N2O Emissions from Managed Soils - Direct N2O emissions from nitrogen inputs into soils.
• 3C5 - Indirect N2O Emissions from Managed Soils - Indirect N2O emissions resulting from nitrogen leaching and runoff.
• 3C6 - Indirect N2O Emissions from Manure Management - Indirect N2O emissions from manure management practices.
• 3C7 - Rice Cultivation - Methane emissions from flooded rice fields.
• 3C8 - Other - Additional sources and sinks not categorized elsewhere (specify as needed).

3D - Other

• 3D1 - Harvested Wood Products - Changes in carbon stocks and emissions/removals from harvested wood products.
• 3D2 - Other - Additional categories not covered elsewhere (specify as needed).

Overview of Emissions from the AFOLU Sector

The AFOLU sector in the Republic of Mauritius functions as a net sink. This sector encompasses GHG emissions from agricultural activities, including methane (CH4) from enteric fermentation and both methane and nitrous oxide (N2O) from cattle manure management. Another significant source within the AFOLU sector is the aggregate sources and non-CO2 emissions on land (3.C), which includes emissions from biomass burning and both direct and indirect N2O emissions from managed soils and manure management. While harvested wood products (3.D.1) represent a smaller emissions category, the primary sink category is land use, particularly forest land (3.B.1), which contributes to the sector's overall net sink status in Mauritius.

Agriculture contributes to greenhouse gas emission primarily through the emission and consumption of GHGs such as methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). 

Methane emissions primarily arise from enteric fermentation in livestock, particularly cattle, as well as from manure management practices that result in anaerobic decomposition. Rice cultivation is another source of methane, especially in flooded fields where anaerobic conditions promote the production of this potent greenhouse gas. The application of synthetic and organic fertilizers on agricultural soils leads to nitrous oxide emissions, a greenhouse gas with a much higher global warming potential than carbon dioxide.

Forestry and land use change are critical components of this sector, with deforestation and land degradation contributing to carbon dioxide emissions. When forests are cleared for agriculture or other land uses, the carbon stored in trees and soil is released into the atmosphere, exacerbating climate change. Conversely, forests, wetlands, and other natural ecosystems serve as carbon sinks, sequestering carbon dioxide from the atmosphere and playing a crucial role in mitigating emissions. Reforestation, afforestation, and sustainable land management practices are key strategies to enhance these carbon sinks and reduce emissions from land use change. The AFOLU sector's emissions and mitigation potential are closely tied to land management practices, making it a vital area for action in the broader context of climate change mitigation in Mauritius.

This structured overview delineates the diverse sources of GHG emissions within agriculture and underscores its critical economic, social, and environmental roles in Mauritius, illustrating both challenges and contributions to sustainability.

GHG emission trend of AFOLU sector of RoM from 2000 to 2022. source: BTR/NID 2024

The AFOLU sector in the Republic of Mauritius serves as a net sink. From 2000 to 2022, net removals (emissions minus removals) in Mauritius decreased by 5.5%. GHG emissions from agriculture (categories 3.A and 3.C) dropped by 37% over this period, from 140 Gg CO2e to 88 Gg CO2e. Similarly, GHG removals from Land Use, Land-Use Change, and Forestry (LULUCF), specifically categories 3.B and 3.D, fell by 7.4%.

In 2022, the predominant category for removals was Forest Land (3.B.1), which accounted for -430 Gg CO2e. Emissions from livestock (3.A) also decreased by 16%, from 44.7 Gg CO2e in 2000 to 37.3 Gg CO2e in 2022.

Sources of GHGs in Agriculture:

Methane (CH4):

1. Enteric Fermentation: A significant source of methane emissions, particularly from ruminants.
2. Soil Microbial Activity: Methane is produced during the anaerobic decomposition of organic matter in soils, especially in submerged crop fields.

Nitrous Oxide (N2O):

1. Nitrification and Denitrification Processes:
   1. Nitrification: Aerobic microbial oxidation of ammonium to nitrate.
   2. Denitrification: Anaerobic microbial reduction of nitrate to nitrogen gas, releasing nitrous oxide as an intermediate and by-product.
2. Soil Management: Availability of inorganic nitrogen (from fertilizers, manure, etc.) in soil influences these processes.

Carbon Dioxide (CO2):

1. Soil Management Practices: Primary source within agriculture.
2. Agricultural Operations: Use of fuel and burning of crop residues.
3. Off-Site Sources: Manufacturing of farm implements, fertilizers, and pesticides.

Impact of Agriculture:

Economic and Social Role:

1. Agriculture occupies 48% of Mauritius' land area as of 2015.
2. Employs 7.3% of the working population.
3. Contributes 38% to the export commodities but only 3.5% to the GDP in 2017.
4. Provides direct employment to about 45,300 people.

Crops and Land Use:

1. Mainly used for sugarcane, tea, and food crops such as litchi, mango, banana, and pineapple.

Environmental Impact:

1. The AFOLU (Agriculture, Forestry, and Other Land Use) sector is vital for food and nutritional security.
2. Dependent on climatic factors like temperature, rainfall, and humidity.
3. Land constitutes a net sink of GHG removals.
4. Forest land contributes approximately 86.3% to total net emissions/removals from land.

AFOLU- Overall - Net Removals:

CO2 Equivalents:

• Recorded at around -330 Gg, highlighting land's role as a significant carbon sink.

CO2eq. Emissions of the AFOLU Sector - Main Components