Mapping Impact of Tidal Flooding on Solar Salt Farming in Northern Java using a Hydrodynamic Model

The purple-spotted bigeye (Priacanthus tayenus Richardson, 1846) is a demersal fish species with significant commercial value, high market demand, and abundant production. The objective of this study is to investigate the occurrence and intensity of Anisakis larvae infection in purple-spotted bigeye from the northern coast of Java. This research provides information on the distribution of the Anisakis infection, which helps fisheries authorities to understand the risks to human health, reduce harm to the fishing industry, and use these parasites as signs of environmental health. In total, 407 samples of purple-spotted bigeye were gathered from the north coast of Java, namely Lamongan (East Java), Rembang (Central Java), and Indramayu (West Java). Fish were collected from the fishermen who landed the fish in the fishing port from July to October 2023. The highest prevalence of Anisakis larvae infection was found in purple-spotted bigeye caught from the north coast of Central Java (70.7 %), while the lowest prevalence of Anisakis infection was found in samples from West Java (34.8 %). However, the highest mean intensity of Anisakis infection was found in samples originating from West Java (16.45 larvae infected host-1), and the lowest in fish from East Java (7.50 larvae infected host-1). Anisakis larvae are mostly found in the body cavities of purple-spotted bigeye. Direct sequencing of the ITS-rDNA region confirms the Anisakis nematode larvae isolated from the purplespotted bigeye were Anisakis typica.

High tide event has been acknowledged as a major cause of inundation in urban coastal area. This event is expected to increase in the future as an impact of global climate change. Meanwhile, there is still a gap of interest on tidal flood impact of marginal land use such as salt production with its traditional process. This study aims to identify high tide event in Cirebon waters and its impact on solar salt production area. Here we combine hydrodynamic simulation and Geographic Information System (GIS) within inputs from national seamless Digital Elevation Model (DEM) data from National Geospatial Agency, bathymetry, and wind record in May 2018 event. Additionally, this study also proposes coarse analysis of potential loss due to tidal flood event through productivity and pricing data from recent studies. From this research, it is found that 6, 570 ha (84%) of the salt production area has been inundated in that peak event with € 48.69 million of potential loss. This model exposes beneficial information for Indonesia salt sufficiency program as well as coastal disaster risk management.

The influence of the earth-moon-sun system on tide events has long been known. However, the impact can vary in different coast areas. The short-term (monthly and yearly) impact of maximum tides needs to be watched out for in relation to tidal flooding, especially if it is reinforced by bad weather at sea. In 2021 NASA reported the results of the Sea Level Change Science Team study that in the 2030s tidal floods will become more frequent and threatening the coasts of the United States due to the 18.6-year lunar orbit nodal cycle which amplifies the effects of global warming. Analysis of maximum tides on the north coast of Java (using data from Jakarta and Surabaya) and on the south coast of Java (using data from Cilacap) shows that on both the north and the south coast of Java, there is no indication of the nodal cycle of the 18.6 year due to lunar orbit. However, this study shows that in short-term annual and monthly cycles there is a difference in the pattern of maximum tides on the north coast and the south coast of Java. The declination of the sun when it is most northerly (the end of June) and most southerly (the end of December) affects maximum tides on the north coast of Java, as semi-annual cycle. Meanwhile on the south coast of Java, only the southernmost declination of the sun (in the end of December) has an effect on the maximum tide, as annual cycle. For monthly cycles, maximum tides on the north coast of Java are affected by the maximum declination of the moon and moon’s perigee (in Jakarta) or by the moon phases and perigee (in Surabaya). Meanwhile, on the south coast of Java it is only affected by the moon’s phases and perigee.

This research aims to explain the Pasai Muslim diaspora on the North Coast of Java. This research uses historical research methods which include heuristics (primary sources such as Suma Oriental Tome Pires and secondary sources such as Asian Trade and European Influence in the Archipelago between 1500 and around 1630, Sociological Historical Studies of Indonesian Society Volume 1, Islamic Archeology of the Archipelago, Critical Review of History Banten, Sunan Gunung Jati (between Fiction and fact) Grounding Islam with a structural and cultural approach), source criticism, interpretation, and historiography. The results of this research found that the process of the Pasai Muslim diaspora in the North Coast of Java occurred in the 16th century, resulting in the formation of the Cirebon Sultanate. It also shows that the Pasai Muslim diaspora had spread to parts of West Java brought by Sunan Gunung Djati. After controlling the West Java region, Sunan Gunung Djati then founded the Sultanate of Banten, led by his son, Sultan Hassanudin. Keywords: diaspora, Muslim, Pasai, North Coast of Java

Tidal flooding is a natural phenomenon where seawater enters land areas with high sea levels. Tidal flooding is caused by factors, namely forest area decline, land degradation, hydrological conditions disturbances, household waste, improper drainage, and rising tides. The North Coast of Java that has the potential to be affected by tidal flooding is the downstream area of the Cipunagara River Basin, Subang Regency. Factors causing disasters include runoff from the Cipunagara river, sea water intrusion, changes in coastal land use, sea level rise, and the presence of river water overflows every year, which play a role in the expansion of the tidal area of flood inundation. The purpose of this study is to map the risk of tidal flooding based on the hazard index, vulnerability index. The determination of the risk index is carried out using a spatial method to identify the hazard index and vulnerability index, by scoring or overlaying through the GEE and ArcGIS 10.8 applications, as well as qualitative descriptive methods in determining disaster capacity. The high-vulnerability category for tidal flooding is found in the villages of Legon Kulon, Patimban, Pusakaratu, Mundusari, Rancasari, Pamanukan Sebrang, Mulyasari, Pamanukan Hilir, Pamanukan, Lengkong Jaya, and Pusakajaya with a tidal flood vulnerability index scoring range, which is 3.2 – 3.8. The moderate vulnerability category was found in the villages of Bobos, Karangmulya, Rancadaka, and Gempol with a scoring range of 2.6 – 3.2. While the category of low tidal flood vulnerability index was in Tegalurung, Mayangan, Legon Wetan, Pengarengan, and Ranca Hilir with a tidal flood vulnerability index score range of 2.0 – 2.6. This vulnerability index will be expanded to determine the Capacity index and Risk index for the same location of study.

Indonesia has many beaches that attract the attention of tourists, including the north coast of Java. In addition to visual appeal, there are also other potentials such as settlements, agriculture, fisheries, ports, ponds, and other resources. However, there is also a threat to coastal damage caused by, among other things, wave action, tides, abrasion, and tidal flooding. For this reason, in developing coastal areas on the north coast of Java, it is necessary to consider the potential for damage to the coast based on the physical condition of the coast and a system that can classify the vulnerability levels of coastal areas is also needed. The Coastal Vulnerability Index (CVI) can be determined and classified using for example the Gornitz formula, or using data driven model and machine learning based on the coastal parameter data. This study demonstrates how the K-Nearest Neighbor, also known as K-NN algorithm, can be used to classify the level of vulnerability of the coastal areas. This study uses 290 points (locations) along the northern coasts of Java. The parameters that determine the coastal vulnerability are mean sea level (MSL), mean significant wave height (MSWH), mean tidal range (MTR), shoreline changes, landforms and slopes. In this study, the classification of coastal vulnerability levels is classified into 4, namely “low, moderate, high and very high”. The K-NN system uses 80% of the data for training and 20% for testing, with the value of K = 1 to 10. The test results show that the K-NN method is capable of classifying the vulnerability levels of the North Coast of Java. From the test results for values of K = 1 to K = 10, and by randomizing the training data and test data gives an average accuracy rate of 86.21% to 97.13%, with the best K value obtained at K = 2.

Tidal flood is one of the threats to the coastal areas, especially the north coast of Java. The coastal area of Tangerang Regency itself has a history of tidal flood events that occur every year. The tidal flood hazard level can be measured based on the flood characteristic, which includes flood height, flood duration, and flood frequency. Flood characteristic data are obtained by purposive sampling where the tidal flood occurred. Those data are interpolated using Inverse Distance Weighted (IDW) and overlaid to get the tidal flood hazard level in coastal area of Tangerang Regency. The class of non-hazardous dominates Tangerang Regency. The class has 9,727 hectares or 75% of the total coastal area of Tangerang Regency. While the high-class hazard has an area of 1,149 hectares or 9% of the total coastal area of Tangerang Regency. Hazard level may increase in some regions which close to the river mouth. The increasing of hazard level can also be indicated by a low altitude area. Based on the calculation of hazard equilibrium value, the coastal area of Tangerang Regency is dominated by low-class hazard level. There are 12 villages with low-class of hazard level.

Chapter 4 - Building resilient city in coastal urban areas: case study of community adaptation and response toward climate change and tidal floods in Semarang, Indonesia

Gunawan H, Sugiarti, Iskandar S. 2017. Dynamics of mangrove community in revegetation area of Karangsong, north coast of Indramayu District, West Java, Indonesia. Biodiversitas 18: 659-665. Mangrove along the north coast of Java is heavily degraded due to the conversion of land into fish ponds and human settlement areas. A revegetation program has been initiated by the local community of Karangsong Village, Indramayu District, West Java, Indonesia, supported by PT. Pertamina RU VI Indramayu. Our research aimed to study the population dynamics of the mangrove revegetation in Karangsong. Secondary data was collected from the Fishery and Maritime Services of Indramayu and PT. Pertamina. We carried out on-location field observations and we interviewed key respondents. Data was analyzed to describe trends in the diversity index and population dynamics of the mangrove. It was observed that the revegetation effort in the shoreline of Karangsong had covered ± 69.08 hectares which consisting of six species of mangrove and three tree species of coastal vegetation i.e. Rhizophora mucronata Lam., Rhizophora stylosa Griff., Rhizophora apiculata Blume, Avicennia marina (Forssk.) Vierh., Avicennia alba Blume, Sonneratia caseolaris (L.) Engl, Terminalia catappa L., Casuarina equisetifolia L., and Ziziphus mauritiana Lam. The mangrove population increased dramatically, from estimated 25,000 individuals in 2008 to 690,835 individuals in 2016. Rhizophora mucronata was the most dominant species (68.85%), followed by Rhizophora stylosa (18.33%) and Rhizophora apiculata (9.53%). The Shannon diversity index was fluctuated but tend to be increased from 0.80 to 0.95.

In Indonesia’s coastal areas, especially along the North coast of Java, tidal floods are a significant natural disaster threat. This disaster had a serious impact on environmental conditions and resulted in changes in the social and economic order of local communities. A study was conducted to assess the social and economic impacts of tidal flooding on Romantis Beach which is located in Sei Naga Lawan Village, Perbaungan District, Serdang Bedagai Regency. This research aims to identify economic and social impacts on society, as well as analyze mitigation efforts carried out by the government. The research uses a qualitative descriptive approach by collecting data through in-depth interviews. Resource persons include local government officials, affected residents, and communities who have lived in the Romantis Beach area for at least five years. Research findings reveal a significant decline in people’s income, especially those who depend on the fisheries and tourism sectors for their living. Daily income, which previously reached IDR 500,000, decreased to IDR 300,000 after the tidal flood. This condition forces some residents to change professions to survive.From a social aspect, there was no conflict found in society. On the contrary, this disaster actually strengthened community solidarity in recovery efforts. Even though long-term mitigation efforts such as the construction of wave breakers have been hampered due to limited funds, the community remains united in restoring conditions. The local government contributes by building green open spaces as water catchment areas. To increase community resilience, greater attention is needed from various par’ies including the government, NGOs and the private sector in supporting long-term economic recovery and infrastructure development programs.

Cirebon is one of the cities in West Java province. The city is located in the lowlands on the north coast of Java. The low topography factor is closely related to urban problems, such as slums in the Lemahwungkuk sub-district of Cirebon City. This research aims to solve urban problems because, according to the Mayor's Regulation No. 663/Kep.421-DPRKP/2021, Lemahwungkuk sub-district includes Cangkol coastal and Kesunean coastal areas among the eleven slum locations in Cirebon city. In addition, there is a plan to revitalize the coastal border area. The method used in this research is qualitative, using urban design analysis and site analysis. The data sources were obtained through interviews with 20 informants and mapping using ArcGIS 10.8 software. The concept of an environmental approach with an orientation towards the community in the design of the revitalization of the north coast area in Lemahwungkuk District emphasizes the physical environment, infrastructure, economy, socio-culture, disaster, and collaboration between the government and the community. The results of this revitalization design can also be a recommendation for development in Cirebon, West Java. In addition, it recommends conservation and tourism activities on the north coast of Cirebon, West Java. Efforts to overcome the phenomenon of urban sprawl at the research site by changing the pattern of settlements and building layout to improve the quality of the community environment and increase public space and green open space for conservation, tourism, and aesthetic functions of the region.

The rice fields in Indramayu district is 55% of the district area. The average rainfall is 1590 mm per year. Most lands on the North Coast of Java (northern) were potentially affected by sea water intrusion. Extensive observations were 102.321 ha. Field observations were done by survey method. Observations had been conducted on rice fields Pantura, Indramayu, West Java. Soil salinity was measured by using the electromagnetic conductivity meter (EM-38). The results revealed that area had very high salinity which was 22.57%, closest to the beach Indramayu. In the South Region, soil salinity was lower, in accordance with the distance from the coastline. Some areas had a low, medium, and high salinity status in which 58.41%, 8.54% and 10.49%, respectively. Much of the research area had very high Sodium (Na) and ECe (0 - 30 cm) was between 1.37 to 16.38 dS m-1, while the ECe (30 - 70 cm) was between 1.11 to 17.40 dS m-1. This research was expected to assist in the agricultural development planning, especially in wetlands which have been affected by the intrusion of sea water (salinity). Planning for theimplementation of the development of rice varieties that are sensitive to high and very high salinity. Planning and improvement of irrigation networks as sources of clean water for washing the salts or pushing salt water into the sea.Keywords: Coast of Indramayu, rice field, seawater intrusion, soil salinity

The Batujaya site, located in Karawang Regency, West Java, encompasses the Segaran and Talagajaya Villages and is situated near the North Coast of Java and the Citarum River. This area is prone to annual flooding, causes the ground level at this temple site to tend to rise over time which has buried much of the temple complex under 1-2 meters of soil. Electrical Resistivity Tomography (ERT) was employed to explore the subsurface features of this archaeological site, offering a non-destructive and efficient means to uncover buried objects. In this research, acquisition was conducted using Marcapada resistivity meter with 48 electrodes, spacing each electrode along 0.5 m and the configuration used is Wenner. The measurement results are then processed using the Earth Imager application. ERT investigations on Line 1 identified a clay rock layer with high water content (1.3 Ωm, blue), corroborated by surface puddles. This layer lies beneath electrodes 21-36, with varying depths. A sandy clay layer (2 − 5 Ωm, green) was also detected, likely due to water and ion retention. Higher resistivity values (9 − 17.9 Ωm, orange to red) suggested buried temple structures, confirmed by ongoing excavations near electrodes 27-46. Line 2, intended as a baseline comparison, revealed unexpected anomalies (5−7.5 Ωm, yellow to red) indicative of possible buried objects, challenging archaeologists’ initial assumptions. These findings demonstrate the effectiveness of ERT in revealing hidden subsurface features, providing valuable insights beyond surface observations alone.

Detecting the availability of sufficient water in tidal land management is important for agriculture. Tidal flood pattern provides an information of area where has tidal flood as well as drought by time and places. The objectives of this research are 1) to study the tidal flood spatial pattern by using real time data and digital data image processing, 2) to determine a tidal flood classification based on ground water level on a specific location and time, and 3) to study the hydrological factors affecting the flood. The tidal flood pattern can be classified within a block by their ground water fluctuation. The visual analysis with four image of different time, gives a clear differences between tidal flood pattern change and tidal fluctuation. The classification on the moist Landsat TM image after a Tesseled Cap transformation can produce classified image with similar flooded condition with the same range of ground water level. After the test, the tidal flooded pattern was found similar with the classification results. The tidal flood pattern is also recognized having a specific relationship with land use or land utilization type. The land use and land management affect the pattern. The application of geographical information system, especially remote sensing digital image data analysis, will help in determining tidal flood pattern as well as the ground water spatial pattern.

New York City Panel on Climate Change 2019 Report Chapter 5: Mapping Climate Risk