Klasifikasi Habitat Bentik Berdasarkan Citra Sentinel-2 di Kepulauan Kei, Maluku Tenggara

Imagery classification has long been used in analyzing remote sensing data. The use of the classification algorithm model can affect the results in interpreting benthic habitats in shallow water. This study aimed to determine the best classification algorithm model for mapping benthic habitat cover through Sentinel-2 satellite imagery. Three algorithm models were employed: Maximum Likelihood Classification (MLC), Minimum Distance Classification (MDC), and Mahalanobis Distance Classification (MaDC). The benthic habitat types were extracted using Lyzenga correction, giving three categories: coral, seagrass, and sand. The results showed that the application algorithm models of the MLC, MDC, and MaDC on the benthic habitat mapping resulted in an accuracy value that was not significantly different at the 95% confidence interval. However, of the three algorithms used, the MaDC algorithm provides the best results in overall accuracy (78.35%) than the MDC (74.45%) and the MLC (74.33%). It shows that the MaDC algorithm can be referred to as the mapped benthic habitat cover in the Kei Islands. However, this algorithm model needs to be continuously studied and compared to other models in other locations.   Keywords: benthic, habitat classification, Kei Islands, sentine

Analisis Daya Dukung Lahan untuk Pengembangan Budi Daya Kerapu di Perairan Tambak Kecamatan Cilebar, Kabupaten Karawang

The aims of this research were to analyze the land suitability and carrying capacity for groupers culture. The utilized methods were land suitability analysis and carrying capacity analysis. The results of land suitability analysis showed that the area which is fit very suitable criteria is 38.16 ha (17.13%), fit enough suitable is 118.27 ha (53.11%), and appropriate-conditional suitable is 66.26 ha (29.75%). The results of carrying capacity analysis resulted in an area of 156.43 ha which is very suitable for groupers culture development in KJT systems. This area could accommodate as much as 313 ponds which are equivalent to 626 units or 6.257 KJT boxes

Seribu islands in the megacities of Jakarta on the frontlines of the climate crisis

Jakarta, the biggest city in Indonesia, has one district that consists of hundreds of islands that face severe climate hazards called the Seribu Islands complex. This study explores the evidence of local climate trends, the potential impact, and its policy intervention on Seribu Islands, which are classified as small island states and widely recognized as being especially at risk from climate change, threatening their economic and social growth. Long-term in-situ climate data, satellite data, interviews with local stakeholders, and literature reviews were utilized to conduct an exploratory descriptive analysis. The result revealed that Seribu Island experienced a 2.2°C increase in minimum temperature from 1980 until 2021, 3.5-fold of the frequency of extreme temperature and precipitation, 4.17 mm/year of sea level rise, and 10.8 ha land expansion in the densest island. Moreover, about 67% of the inhabitant’s islands were occupied by built-up areas that cover more than 50% of the region. Further, under the worst-case SLR scenario, about 58.4% of the area will be affected, and about 29 islands will disappear. This evidence was also reinforced by every single local respondent’s viewpoint who felt that climate change is occurring in the region. Even though the region faces a severe threat of climate change, the issue of climate change adaptation has not been mainstreamed yet into their local policy. Therefore, the urgency of a real-time climate ground station, a real-time early warning system, and establishing a Regional Disaster Management Agency (BPBD) at the district level have yet to be addressed. Furthermore, the knowledge gained from such case studies is outlined, along with some scientific evidence that may assist small island states in better fostering the opportunities provided by climate change adaptation

Seagrass Condition at Some Small Islands in The Taka Bonerate National Marine Park, South Sulawesi Indonesia

The assessment of seagrass bed condition in Indonesia still refers to the Decree of the State Minister for the Environment (KMNLH) no. 200 of 2004, which considers only one variable, namely the percentage of seagrass cover. To assess the seagrass beds condition to be more in-depth and meaningful, it is necessary to consider the addition of several variables, such as the biotic variables (seagrass species diversity including macroalgae and macro-benthos components) as well as the abiotic variables (reef flat areas and the substrate components). The purpose of this study is to determine the seagrass beds condition in several small islands in the Taka Bonerate National Marine Park by considering the additional analysis using both biotic and abiotic variables as mentioned above. The methodology used in this study is a combination of the use of the standard seagrass transect method, interpretation of satellite imagery related to the seagrass bottom habitat area, and its components on the reef flat of a particular island, as well as weighting and scoring based on those considered additional variables. By applying the criteria in the method, the seagrass bed conditions were then classified into three categories, namely seagrass in good, moderate, and unfavorable conditions, respectively. The results of the total score assessment on several small islands in Taka Bonerate Islands show that the seagrass bed in Latondu Besar Island is in good conditions with the highest score of (316) compared to Tarupa Besar, Jinato, Rajuni Kecil, and Tinabo Besar Islands with an average score of (173). The results of this study indicate that the assessment of seagrass conditions is more meaningful in terms of seagrass ecology than based on seagrass cover alone. However, this study requires a lot of validation for its application in assessing the condition of seagrass beds in other islands in Indonesia

The reef health index for coral reefs management in Indonesia

The Indonesian coral reef faced significant challenges due to the lack of precise instruments for assessing the health status of corals, which is crucial for ensuring their long-term viability. The reef health index was established by utilizing extensive monitoring data from Indonesia, incorporating metrics such as live coral cover, resilience level, and biomass of the focal reef fish species. In the year 2021, a comprehensive collection of coral reef data was conducted at 22 distinct places within the waters of Indonesia. It is anticipated that the reef health index data will assist stakeholders in effectively and sustainably managing coral reefs. The findings indicate that the reef health index in Indonesia exhibits a range of values from 2 to 7, with 7 being the highest attainable score. Since observations began in 2014, the Indonesian reef health index has maintained a stable value of 5. The available evidence suggests that there is an ongoing occurrence of coral reef degradation in Indonesian waters, as seen by the diminished biomass of the targeted reef fish species. Nevertheless, the potential for recovery of damaged coral reefs exists if the forces that initiate the damage can be mitigated or eradicated