Carbon Stock Estimates for Acacia mangium Forests in Malaysia and Indonesia Potential for Implementation of Afforestation and Reforestation CDM Projects

: The Conference of the Parties 9 in Milano, Italy (COP 9, 2003) approved modalities and procedures for afforestation and reforestation (A/R) project activities under the Clean Development Mechanism (CDM) of the Kyoto Protocol. According to the conclusions of COP 9, several approaches are available to monitor temporary carbon sequestration in A/R-CDM projects. Developing baselines for such monitoring is difficult because of a lack of basic growth and management data. In this paper, we present guidelines for preparing a project design document (PDD), in which growth and yield prediction in plantation forests plays an important role, and present a methodology for modeling and estimating carbon stocks using inventory data from Acacia mangium plantations in Malaysia and Indonesia.


Introduction
Indonesia and Malaysia have the opportunity to serve as host countries for Clean Development Mechanism (CDM) projects through afforestation and reforestation (A/R) efforts. The Conference of the Parties 9 in Milano, Italy (COP 9, 2003) sought to clarify modalities and procedures of A/R-CDM project implementation under the Kyoto Protocol. One of the most difficult requirements for the formulation of A/R-CDM projects is meeting the requirements of an "additionality scheme." Project participants are asked to describe the project scenario in the form of a project design document (PDD). The PDD must clearly define the "additionality scheme," or how the project will augment carbon sequestration with respect to the identified baseline scenario.
In this paper, we present brief guidelines for designing a PDD and discuss our approach to developing suitable carbon stock estimates for Acacia mangium plantation forests in Malaysia and Indonesia. These countries have a history of using Acacia mangium plantations for land rehabilitation under short rotation-high yield management schemes. Plantation forestry plays an important role in climate change mitigation, especially under the CDM scenario. Acacia mangium shows promise as tropical plantation tree species that provides significant benefits to investors and indigenous populations involved in A/R-CDM projects.

Modalities and Procedures for A/R-CDM Projects
Project participants are asked to submit the completed version of a CDM-PDD, together with any attachments, to an accredited designated operational entity for validation (Figures 1 and 2

CDM Project Design Documents
A CDM-PDD presents information on the essential technical and organizational aspects of the project activity and is a key input into the validation, registration, and verification of the project, as required under the Kyoto Protocol. The CDM-PDD contains information on the project activity, the approved baseline methodology applied to the project activity, and the approved monitoring methodology applied to the project. It discusses and justifies the choice of baseline methodology and the applied monitoring concept, including monitoring data and calculation methods.
The following is a general overview of PDD design in a CDM project (UNFCCC, yield table is quite important. However, due to a lack of long-term observed plantation data, it can be difficult to construct a precise table for the deviation of local yield. In this paper, we temporally construct a yield table that is derived from various plots in Acacia mangium plantations and propose a procedure for estimating carbon stocks.

Data Collection
Acacia mangium is a fast growing tree species that is well suited to reforestation efforts in degraded landscapes. In Malaysia, it has been widely planted since the beginning of the Compensatory Forest Plantation Program (CFPP) in 1981. Its initial survival rate is relatively high, but disease (frequently heart rot) sometimes appears in later years. Figure 3 (below), shows the location of field sites where data was collected for the yield table we have constructed (Matsumura and Ismail, 1996;Matsumura, 2004). Sites were distributed throughout the Malaysian Peninsula.

Methods
According to the conclusions of COP 9, project participants must account for all changes in the following five carbon pools: 1) Above-ground biomass (leaf, branch, and trunk) 2) Below-ground biomass (root) 3) Dead wood 20 Matsumura et al.

5) Soil organic carbon
Mean carbon stock (MC) is usually estimated by the biomass expansion factors method (IPCC 2003) that includes above-and below-ground biomass carbon pools: where the variables are defined as follows: MC: mean carbon stock (tC/ha) Merchantable volume is generally estimated by the allometric relationship between diameter and height. The following basic equations were used to calculate mean values in Acacia mangium stands (Matsumura and Ismail, 1996;Matsumura, 2004 where, a = f(trees per ha), b = 1.5474, and c = 0.8093 A flow chart of the growth model used to construct the yield table is shown in Figure 4. The yield table we derived for each study site was compared with the yield tables from other study sites in West Java and in Sabah (Inose, 1991).

Results and Discussion
The comparison among study sites at age 10 is shown in depended on the total number of trees per ha. Figure 5 (below) shows estimated carbon stocks in the West Java and Malaysia study sites. To ensure a smooth implementation of A/R-CDM projects, it is also important to analyze the growth and carbon stock difference at local project sites from the investors' and communities' points of view, respectively. The design of A/R-CDM projects and PDD layout should become increasingly easier as general yield tables are developed for promising tree species in the coming years.