Mangrove Above-Ground Biomass and Carbon Stock in the Karimunjawa-Kemujan Islands Estimated from Unmanned Aerial Vehicle-Imagery

Anindya Wirasatriya,Terry Louise Kepel,Muhammad Helmi,Mariska A Kusumaningtyas,Novi Susetyo Adi,Raghab Ray,Raditya Rizki Ananta,Restu N A Ati,Takashi Nakamura,Denny Nugroho Sugianto,Lilik Maslukah,Sigit Bayhu Iryanthony,Rempei Suwa,Kazuo Nadaoka,Rudhi Pribadi

doi:10.3390/su14020706

Abstract

Blue carbon ecosystems in the Karimunjawa Islands may play a vital role in absorbing and storing the releasing carbon from the Java Sea. The present study investigated mangrove above-ground biomass (AGB) and carbon stock in the Karimunjawa-Kemujan Islands, the largest mangrove area in the Karimunjawa Islands. Taking the aerial photos from an Unmanned Aerial Vehicle combined with Global Navigation Satellite System (GNSS) measurements, we generated Digital Surface Model (DSM) and Digital Terrain Model (DTM) with high accuracy. We calculated mangrove canopy height by subtracting DSM from DTM and then converted it into Lorey’s height. The highest mangrove canopy is located along the coastline facing the sea, ranging from 8 m to 15 m. Stunted mangroves 1 m to 8 m in height are detected mainly in the inner areas. AGBs were calculated using an allometric equation destined for the Southeast and East Asia region. Above-ground carbon biomass is half of AGB. The AGB and carbon biomass of mangroves in the Karimunjawa-Kemujan Islands range from 8 Mg/ha to 328 Mg/ha, and from 4 MgC/ha to 164 MgC/ha, respectively. With a total area of 238.98 ha, the potential above-ground carbon stored in the study area is estimated as 16,555.46 Mg.

Highlights

It has been widely known that anthropogenic carbon dioxide emissions (CO2 ) become the main contributor to climate change
Since the mangrove area of Karimunjawa-Kemujan Islands can can be categorized as a flat plain, as denoted by the distribution of Digital Terrain Model (DTM) which only varies be categorized as a flat plain, as denoted by the distribution of DTM which only varies from 0 m to 1.25 m (Figure 1b), calculated canopy height varies from 1 to 23 m (Figure 3b)
The Java Sea is known as a carbon source area that contributes to releasing carbon dioxide into the atmosphere

Summary

Introduction

It has been widely known that anthropogenic carbon dioxide emissions (CO2 ) become the main contributor to climate change. CO2 concentrations in 2000, 2010, and 2018 were 369.55 ppm, 389.90 ppm, and 409.68 ppm, Sustainability 2022, 14, 706. Reducing the CO2 concentration in the atmosphere is one of the critical measures for combating climate change. Coastal ecosystems, i.e., mangroves, seagrass, and salt marshes, play important roles as the blue carbon ecosystems, referring to their abilities to sequester the amounts of carbon per unit area more significantly than the terrestrial forest [3]. Mangrove and seagrass ecosystems have become the major blue carbon ecosystem [4]. Conserving the blue carbon ecosystems has become one of the strategies for mitigating anthropogenic carbon emissions

Methods

Results

Discussion

Conclusion