Estimation of Carbon Stock Changes in Above Ground Woody Biomass due to Volcano Pyroclastic Flow and Pyroclastic Surge

Abstract

Merapi Volcano National Park (MVNP) is susceptible to volcanic hazard since it is located around Merapi
volcano, especially pyroclastic flow. Carbon sequestration in the national park is becoming a priority of forest development
as stipulated in Government Regulation Number 28 Year 2011 and Number 49 Year 2011. This study aims to know
the effect of pyroclastic event to carbon stock in MVNP. In this study the natural carbon rate recovery in MVNP was
estimated to determine the growth rate of natural carbon recovery in MVNP. To estimate carbon stock change in MVNP,
2006 QuickBird and 2011 GeoEye satellite imageries were used. Object based image segmentation of high resolution
satellites imagery could recognize physical dimensions of individual trees such as crown projection area (CPA). In this
study, carbon stock was derived using allometric equation based on measured diameter at breast height (DBH) in the
field. A model was developed to estimate carbon stock based on DBH estimation in the field and segmented CPA from
the image. Based on the segmentation process, the model of CPA and Carbon in MVNP was developed. The F score
which indicate the accuracy of segmentation of needle leaf and broadleaved of 2011 GeoEye were 0.68 and 0.54 respectively.
Logarithmic model which has 6.37 % error was used to estimate broadleaved carbon stock while quadratic model
which has 10.31 % error was used to estimate Pine tree carbon stock in MVNP.