How do you assess the importance of forests in mitigating greenhouse gas (GHG) emissions in Vietnam?

Carina van Weelden, implementation manager at the German Development Agency, known as GIZ

GHG emissions play a critical role in effectively addressing climate change. The Vietnamese government has committed to contributing to keeping the global average temperature increase below 1.5°C, as outlined in its Nationally Determined Contribution (NDC) in 2022.

To achieve this, the Vietnamese government has set ambitious climate change mitigation targets. By 2030, the forestry and land use sector is expected to achieve net-negative emissions - absorbing more GHGs than it emits - by sequestering at least 95 million tonnes of CO2 equivalent, as outlined in the National Climate Change Strategy. This figure is nearly double the projected emissions in the 2020 NDC’s business-as-usual scenario, which estimated only 49.2 million tonnes of CO2 equivalent.

This is highly ambitious for the forestry sector, as most of the net-negative emissions must come from forestry, while other land uses, such as agriculture, continue to emit GHGs.

The NDC targets align well with the Vietnam Forestry Development Strategy for 2030, with a vision to 2050. The strategy sets out socioeconomic and environmental goals for the forestry sector, including increasing the supply of large timber from domestically planted forests. To achieve the national NDC targets, a domestic emissions trading system could be a key policy and market tool.

Vietnam has approximately 1.6 million hectares of acacia plantations, accounting for 45 per cent of the country’s total planted forest area. How do you evaluate the high mitigation potential of acacia plantations in Vietnam?

Acacia plantations are concentrated in various regions across the country, particularly in the northern midlands and mountains, the north-central coast, and the Central Highlands.

As part of a project to train forest owners on establishing baselines and estimating emission reductions for a hypothetical carbon scheme, a study and training programme was conducted from September to December 2024 at two forestry companies, namely Quy Nhon Forestry Co., Ltd. and Song Kon Forestry Co., Ltd. in what is now part of Gia Lai province.

The focus of the analysis was to identify differences between short and long rotation cycles in acacia plantations to provide insights into their carbon sequestration potential per hectare. A total of 57 standard plots were inventoried, and over 1,000 trees were measured.

The data collected were consistent and reliable, demonstrating the significant carbon sequestration potential of hybrid acacia plantations in Vietnam through extended rotation cycles. The study’s results highlight the substantial GHG emission reduction potential for large-scale, homogeneous land use types like short-rotation acacia plantations.

Transitioning from biomass production to large-timber production through silvicultural measures and extending the rotation cycle from five to 11 years could result in an average long-term carbon stock of 221 tCO2 per ha for the 11-year cycle (projected scenario) compared to 78 tCO2 per ha for the five-year cycle (baseline scenario).

According to methodology that quantifies GHG emission reductions and removals generated from improving forest management practices to increase the carbon stock on land, this equates to an additional carbon sequestration of 4.2 t CO2e/ha/year. This value is considered conservative, as it only accounts for carbon sequestered in above-ground and below-ground biomass.

How do demonstration plots transitioning from short- to long-rotation acacia plantations, which is a part of the project to scale up forest management and certification in Vietnam, contribute to increased carbon sequestration?

The demonstration plots within the project applied various sustainable forest management approaches, including species combinations and tree age diversity. Most demonstration plots focused on transitioning from short-rotation to long-rotation acacia plantations for large-timber production, such as those at Quy Nhon and Song Kon Forestry. The initiative assessed impact on carbon sequestration when transitioning short-rotation acacia plantations in Vietnam to an 11-year cycle for large-timber production.

To measure the carbon stock of acacia plantations at different ages, the project applied improved forest management methodology from VERRA, a widely used global standard under the Verified Carbon Standard. This methodology focuses on increasing carbon sequestration through extended harvest cycles.

Thus, transitioning to sustainable forest management not only enhances timber value but also provides additional carbon benefits, contributing to climate change mitigation goals, provided the extended forest rotation cycle is maintained over the long term.