CARBON DYNAMIC SIMULATION ON GRASBERG RECLAMATION AREA PT FREEPORT INDONESIA USING CENTURY 4.0 MODEL

• Main Author: Rizky Nur Aeni, Alifa
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/50711
• Institution: Institut Teknologi Bandung

Open-pit mining often lead to heavy natural damage. A reclamation needs to be applied to recover and improve the environment quality and post-mining area ecosystem to give the function back. One of post-mining reclamation area potential is the utilization of vegetation as a CO2 atmospheric absorption area, which stored in the form of carbon or biomass. There are several methods to quantify the carbon dynamic in reclamation area. One of them is modeling using Century 4.0. The model which developed by Parton in 1993, has the ability to count vegetation productivity as a function of climate and shading factors. This study aims to simulate carbon dynamics in a condition that generally represent the development of reclaimed stands in PT. Freeport Indonesia reclamation area in Grasberg that occurred for 30 years using Century 4.0 model, Grassland/Crop sub model. Its results will be used to estimate carbon storage in Grasberg area consisting of different-aged reclaimed stands on 2019. Research area is dominated by alpine native species, Deschampsia klossii. This research method started with data collection and literature study. Then, parameterization of Century 4.0 was done to suit the conditions of the research area and the characteristics of Deschampsia klossii. Furthermore, the model interpretation and the model accuracy test were performed using MAPE as an indicator. The result shows that the parameterization output is realistic with MAPE index 8.96% (very accurate). The 30 years parameterized model shows the carbon value tends to be stable after 26-30 years later, which is around 149 g / m2. The total estimated carbon storage in Grasberg area on 2019 which is calculated using Century 4.0 output for the alpine and subalpine zones is 353.89 MgC for an area of 236.29 Ha and 204.18 MgC for an area of 142.47 Ha, therefore the total carbon in the Grasberg reclamation area of PT. Freeport Indonesia in 2019 is 558.07 MgC.