The Status of Indonesian Coastal Ecosystems 2019

After the long term monitoring program through COREMAP-CTI, our scientists have revealed that, in general, the Indonesian coastal ecosystems are in moderate condition. 

Seagrass

Seagrass ecosystem is a key part of Indonesia’s marine environment providing significant ecosystem services through supporting fisheries production, maintaining coastal ecosystem function, and mitigating climate change. Despite these essential roles, however, seagrasses are declining globally, while information about seagrass condition is lacking in Indonesia. In 2015, we established a nation-wide seagrass monitoring program to assess the status and condition of seagrass habitat in Indonesia. We collected basic parameter data, e.g. species composition and abundance, at 32 monitoring sites throughout the nation. Our monitoring program in 2018-2019 observed that Indonesia’s seagrass meadows are generally multispecies meadows, with seven to nine seagrass species, and in moderate condition, indicated by relatively fair abundance (30-40 percent cover). Furthermore, we also found that seagrasses in the Eastern part of Indonesia are generally higher in percent cover and species richness than ones in the Western part. The seagrass condition may be related to the presence of anthropogenic threats to seagrass ecosystems observed during the monitoring, i.e., fisheries activities, boat activities, and coastal development. Based on these findings, we highlight the importance of conservation management in protecting seagrass ecosystem from anthropogenic threats. 

Seagrass Richness in Indonesia 2018-2019

The Status of Seagrass Meadow in Indonesia 2018-2019

Coral Reefs

During the period of 1993 to 2019, in general, there were about 30.85 ± 0.29% of reefs having more than 50 % coral cover (good and excellent reefs) and these were relatively stable despite upward and downward trends for excellent and good reefs respectively, in the last five years. On the other hand, 69.15 ±0.29 % of the reefs had less than 50% coral cover (poor and fair reefs) and the trends were fluctuating. In this case,    these reefs are unlikely stable, having more space for coral recruits to attach and grow but very vulnerable to stressors.

Trend of coral reef conditions in Indonesia

Global stressor, especially elevated sea surface temperature, has a huge impact on Indonesia coral reefs. The trend of coral reef condition appears to be declining between 2015 and 2016 due to mainly bleaching event. However, such bleaching event did not occur at all locations as Indonesia    coral reefs are influenced by different types of hydrodynamic regimes of two oceans (Pacific and the Indian Ocean). In addition, the geomorphological conditions of Indonesia’s Islands are quite diverse, making the impact of elevated sea surface temperature vary among reefs.

Data from COREMAP-CTI’s monitoring locations also confirms that there was a significant decline in coral cover between 2015 and 2016 and followed by a gradual increase until 2019 (Figure 5). The data was collected by using underwater photo transect from plenty of reefs across Indonesian waters. In short, the recovery process after the bleaching event has been progressing and this evidence gives hope to the management regime amid the global declining trends of coral cover.
 

Trend of coral cover from COREMAP-CTI monitoring sites (n: number of reefs monitored)

The Condition of Indonesian Coral Reefs 2019

Mangrove

Indonesia has the most potential mangrove ecosystem in the world since it has a majority of the global mangrove area. As many as 22.6% of world mangrove has been established in this tropical archipelagic country. Consequently, it delivers highly functions and services for surrounding ecosystems and residents. However, the area has been decreasing during the last decades due to coastal area modernizations, land-use changes and other human activities. A monitoring program for mangrove health has been initiated during COREMAP CTI –LIPI project which supports coral reef ecosystem existence since 2015. The program is aimed to assess mangrove stand structure and figured out its community health as the most important component in ecosystem sustainability. A robust, affordable, simple and scientific-based methodology was developed in 2014 involving photography analysis approach to support the program. Recently, the method has been implemented along 40 sites where most of the sites were monitored frequently. Our recent finding showed that Indonesian mangrove was categorized in a good condition with slightly increasing on its canopy coverage average during 2015-2019. West Indonesia sites have a smaller morphological size, denser, and more Rhizophoradomination. On the other hand, The east part was generally found in larger morphological size, fewer stands, and more various species in the majority. Collected datasets have been further analyzed to develop Mangrove Health Index (MHI) for Indonesian mangrove. Index development provides an equation or formula and healthy level criteria which are potentially adopted as a new standard in Indonesia and applied in further studies. On the other hand, we have been developing MACADA, an android-based application for collecting and analyzing fieldwork data to be more efficient and paperless. MACADA obtains all variables needed for MHI calculation and designed for a flexible data sharing ability to a certain cloud database. This feature would be a powerful base to develop one database in Indonesia mangrove data management. A next-step study should be important to enlarge the scope of MHI through the ecosystem, by adding some features such as area, social-economy perceptions, substrate profile and biota potentials.

The Recent Mangrove Canopy Coverage (Method: Hemispherical photography (Dharmawan & Pramudji 2017)

Mangrove Density (Method :Dharmawan & Pramudji 2017)

Trunk Diameter (Method: Hemispherical photography (Dharmawan & Pramudji 2017) 

Recommendation

  • Establish more MPAs to minimize the human factors while preserving the ecosystems 
  • Improve people awareness so they will become our greatest asset in conservation programs
  • Promoting sustainable fishing practices
  • Habitat restoration