THE ROLE OF PASURUAN AND PROBOLINGGO MANGROVE ECOSYSTEMS IN GLOBAL CLIMATE CHANGE MITIGATION
Mangroves are coastal ecosystems that thrive along tropical and subtropical lines throughout the world (Kauffman and Donato, 2012; Liu et al., 2014). Mangroves provide many ecosystem services, including spawning and nurseries for fish and crustaceans, nutrition cycles, storm and tsunami protection, wood production, and ecotourism (Murdiyarso et al., 2015).
Although mangrove forests only account for 0.7% of the earth’s tropical forest area, mangrove degradation accounts for 10% of total emissions from deforestation in the tropics (Giri et al., 2011; Murdiyarso et al., 2015). Mangroves have been shown to absorb carbon (C) which is globally significant. It is estimated that mangrove soils store C two to five times higher than any terrestrial forest (Kauffman and Donato, 2012).
High plant growth and density, coupled with waterlogged anaerobic soils, results in long-term and high C storage. In the Indo-Pacific region and the Indonesian archipelago, mangroves store an average of 1,023 MgC / Ha and 1,083 MgC / Ha, respectively. A total of 2.9 Mha of Indonesia’s mangrove forests absorbs up to 3.14 PgC (Murdiyarso et al., 2015).
Therefore, mangrove forests in Indonesia have the potential for mitigating global climate change and more than 35% of mangrove forests have been reduced globally since 1980 with a decline rate of 2-8% per year (Polidoro et al., 2010). In Indonesia, the development and expansion of aquaculture have reduced mangrove cover by more than 40% in the last three decades (Murdiyarso et al., 2015). Mangrove rehabilitation and restoration programs have been carried out in many areas where coastal protection and ecotourism are added as conservation goals (Donato et al., 2011; Lunstrum and Chen, 2014).
Recently, absorption of C was added as a goal and strategy for conservation and rehabilitation of project-based mangroves through carbon credit financial incentives (Arifanti et al., 2019; Donato et al., 2011). This interest has encouraged measurement and study of the capacity of mangrove forests to store C and store atmospheric CO2. Furthermore, Indonesia contains 20% of the world’s mangrove forests and has the wealthiest mangrove diversity in the world, of which 45 out of 70 species of mangroves exist in Indonesia (Arifanti et al., 2019; Asadi et al., 2018b).
Meanwhile, 50% of mangrove forests in Java are located in East Java Province, which is 18,253 ha from 34,491 ha (Suhardjono, 2013). Therefore, an inventory of mangroves in the province of East Java is essential to access the structure of the forest and its biomass ecosystem, where this research is conducted in fragmented mangrove forests in Pasuruan and Probolinggo Districts, East Java, Indonesia.
The results showed that there were 383 individual trees from four exact mangrove species observed in the study area, namely: Avicennia alba, Avicennia marina, Rhizophora apiculata, and Rhizophora mucronata with a total density of 2553 mangrove stands / Ha. Rhizophora genus constitutes 93% of the entire mangrove individual; therefore, it dominates the important value index. Besides, the average biomass and C stock of mangrove stands are 482.09 ± 159.57 MgB / Ha and 226.58 ± 75 MgC / Ha. Meanwhile, mangroves save 314.27 ± 24.91 MgC / Ha, where on average, soil C stocks constitute 58% of the total reserves of mangrove ecosystems in the entire study area.
Muhammad Arif Asadi, Arizal Mahendra Rahardani, Bambang Semedi, and Agoes Soegianto*