Studi Potensi Daerah Genangan Banjir Pasang (rob) Perairan Meulaboh dengan Sistem Informasi Geografis (SIG) Studi Potensi Daerah Genangan Banjir Pasang (rob) Perairan Meulaboh dengan Sistem Informasi Geografis (SIG) (Kajian Teknis)

Abstrak Kota Meulaboh adalah salah satu daerah di provinsi Nanggroe Aceh Darussalam yang berada di wilayah perairan Lautan Samudra Hindia sebagai sarana Pelabuhan. Pelabuhan Meulaboh sangat berperan penting dalam meningkatkan perekonomian dan memenuhi kebutuhan masyarakat khususnya di Wilayah Kabupaten Aceh Barat. Daerah perairan pantai sangat rentan terhadap banjir pasang (rob) akibat fluktuasi muka air laut dengan kejadian pasang tertinggi (Highest Water Level) yang berpotensi mengakibatkan daerah genangan banjir di sekitar wilayah pemukiman penduduk. Studi penelitian dilakukan untuk menganalisis pemetaan potensi daerah genangan banjir pasang (rob) menggunakan Sistem Informasi Geografis (SIG). Elevasi tinggi pasang surut dianalisis dengan metode Admiralty, penggambaran elevasi kontur permukaan tanah dan banjir pasang (rob) dianalisis berdasarkan data Digital Elevation Model (DEM), dan pemetaan potensi daerah genangan banjir antara elevasi permukaan banjir pasang (rob) dengan peta administratif Kota Meulaboh dilakukan dengan Sistem Informasi Geografis (SIG) yang menggunakan software Arcgis. Hasil penelitian menunjukan elevasi muka air banjir pasang (rob) tertinggi berada di ketinggian 0.78 m di atas permukaan laut rata-rata (MSL) dan mengakibatkan potensi luas daerah genangan banjir mencapai 18.18 Km2. Luas daerah genangan banjir mengakibatkan 11 desa terkena dampak dan mengakibatkan kerugian bagi masyarakat khususnya di wilayah Desa Kampung Pasir, Suak Indrapuri, Suak Raya, dan Suak Nie. Kata-kata Kunci: Meulaboh, pasang surut, admiralty, dan sistem informasi geografis. Abstract Meulaboh City is one of the regions in the province of Nanggroe Aceh Darussalam in the territorial waters Indian Ocean as a port. Meulaboh Port is very important in improving the economy and meeting the needs of the community, especially in the District of West Aceh. Coastal waters are very susceptible to tidal flooding (rob) due to sea level fluctuations with the highest water level which has the potential to cause flooding areas around residential areas. The research study was conducted to analyze the mapping of potential tidal flood areas (rob) using Geographic Information Systems (GIS). Tidal height analysis is carried out using the Admiralty method, depiction of ground surface contour elevation and tidal flooding (rob) is analyzed based on Digital Elevation Model (DEM) data, and mapping of potential inundation areas between tidal flood surface elevations (ROB) with administrative maps of Meulaboh City carried out with a Geographic Information System (GIS) that uses Arcgis software. The results showed that the highest tidal flood water level (rob) was at an altitude of 0.78 m above the mean sea level (MSL) and resulted in the potential area of ​​flood inundation areas reaching 18.18 Km2. The total of ​​flood inundation area affected 11 villages and caused losses to the community, especially in the villages of Kampung Pasir, Suak Indrapuri, Suak Raya, and Suak Nie. Keywords: Meulaboh, tides, admiralty, and geographic information systems.

Spatial Modeling Of Coastal Flood Due To The Fishpond To Tidal Waves In Bengkalis, Indonesia

Bengkalis Island is one of the small islands in Riau Province, which is located on the east coast of Sumatra. It is separated from the island of Sumatra and is in the middle of the Malacca Straits, which is directly facing the ocean and vulnarble to affected by the enormous energy of the tidal waves that propagate on the land surface. Make coastal areas inundated by tidal floods. This is exacerbated by the conversion of mangrove land into Fishponds, which is carried out en masse to support the economy of the Bengkalis community. The degradation of mangrove land, it is also exacerbated by global warming that causes rising sea level. it very vulnerable to coastal areas, especially in the research area. This research method uses geospatial modeling, using tidal data from the geospatial information agency (BIG), land cover image classification, soil surface roughness index, and flood scenarios. The results of this study we found that many coastal areas are prone to tidal flooding. At various maximum heights, there are variations in the distribu-tion of tidal flooding. For the final decision, we use the worst scenario using the highest tidal discharge, which is 3.4 meters. This simulation model inundated more than 74% of use in coastal areas. Not only that; many, agricultural areas were also affected by this tidal flood. We developed this simulation for analysis of losses due to the tidal wave, and we, found a loss index that reached 62% of the total loss of residential areas, including the loss of infrastructure and residen-tial buildings.

The impact of mangrove damage on tidal flooding in the subdistrict of Tugu, Semarang, Central Java

Expansion of industrial areas, aquaculture, settlements, and limited knowledge of the community about the function of mangroves allegedly led to the conversion of mangrove functions in the early 1990s. This study aimed to map the condition of mangroves from 1988, 1990, 1995, 2008, to 2021 and their effect on the widespread of tidal flooding in three villages (Mangkang Kulon, Mangunharjo, Mangkang Wetan) in Tugu subdistrict, Semarang City. The research method was carried out by using spatiotemporal analysis of Landsat 5 and Landsat 8 imagery through the supervised approach (Maximum Likelihood algorithm). In order to map the correlation of mangrove damage with the widespread impact of tidal flooding, an overlay analysis of land use maps was carried out in 1988, 1990, 1995, 2008 and 2021. The results of the study showed that mangrove damage is correlated with the widespread of tidal flooding that drowns settlements, ponds, and agricultural land. Data analysis showed that the mangrove area in three villages has decreased from 1988 to 2021, covering an area of 242.66 ha. This condition is one of the triggers for the increase in tidal flooding area from 1988 to 2021, covering an area of 253.135 ha. As a natural barrier to prevent abrasion and tidal flooding, mangrove conservation is very necessary, considering the impact of tidal flooding on the coast of Semarang City is increasingly widespread.

US Commuting delays from tidal flooding worsen with sea level rise

Although sea level rise is predicted to cause severe societal impacts at the end of the 21st century, few studies quantify the impacts coastal communities already face and empirical evidence regarding contemporary adaptive behaviors to these contemporary impacts remains limited. Here we combine complete road networks, historical and projected flood exposure, and the home/work locations of 500 million person-years for US coastal commuters to estimate the historic and projected delays due to SLR-related tidal flooding. We find that tidal flooding currently delays coastal commuters by an average of 22 minutes (+/- 4.4), increasing to 183 (+/- 33) to 643 (+/- 108) minutes by 2060 under current sea level rise scenarios. Furthermore, adaptive changes in residential and work locations from 2000-2015 reduced delays for coastal residents in 40% of U.S. counties. In the absence of policy, these commuting delays could lead to capital and residential flight from currently thriving coastal economic zones.

Rob Potential in the Coastal City of Kupang, East Nusa Tenggara (NTT)

Coastal areas are dynamic and vulnerable to environmental changes, both due to natural processes and human activities, the coastal waters in Kupang City are strategic in supporting the development of the economic sector. Coastal areas have unique characteristics, both in terms of bio-geophysics and social, economic and cultural aspects. Some have a high level of vulnerability to global warming. The high value of vulnerability is inseparable from the geomorphological conditions of Kupang City in the form of sandy beaches and coastal erosion. This condition caused Kupang City to become one of the areas affected by tidal flooding. This research is a preliminary study which aims to determine the potential for rob in the coastal city of East Nusa Tenggara that occurred in February 2014. The impact of the tidal floods submerged residents' houses above the knees of adults as high as 70 cm.. The results of this study were to determine the potential for tidal reoccurrence in the city of Kupang, NTT based on tidal forecasting data. Based on the results of the analysis using the Admiralty method, it was found that the Formzhal (F) value for the coast of Kupang City was 25.82, the position of the lowest water level at Oesapa 2 Beach was 206.9 cm, while the sea level elevation position reached the highest peak on Kelapa Lima 2 Beach, namely 478, 5 cm. The value of the harmonic analysis results from the coastal area of Kupang City has HHWL (Highest High Water Level) which is 340.09 cm, the MSL (Mean Sea Level) value is 212.07 cm, and LLWL (Lowest Low Water Level) is 73.36 cm based on these results. The Kupang coast has the potential for tidal flooding.

KONSEP WATERFRONT KALI MBEROK KOTA LAMA SEMARANG

Kali Mberok Kota Lama Semarang is a river that has a lot of history during the Dutch colonial era in Central Java. The revitalization of the Kota Lama area is now being carried out by turning old buildings into places for office activities and also for supporting tourism activities in the Old City. The development of the revitalization of the Kota Lama cultural heritage area was hampered by the problem of tidal flooding and street lighting. The waterfront concept for Kali Mberok is one solution to overcome the obstacles to revitalizing the Old City by adding green open spaces on the edge of Kali Mberok. The implementation of a waterfront in Kali mberok Kota Lama will have a positive impact on reducing buildings on the riverbank and also increasing street lighting with the addition of public open spaces. Innovatively, this study will lead and develop the potential of Kali Mberok in the design of Kali Mberok waterfront tourism around Kota Lama with an emphasis on the Waterfront conceptAbstrak: Abstrak Kali Mberok Kota Lama Semarang adalah salah sungai yang memiliki banyak sejarah di masa kolonial Belanda di Jawa Tengah. Revitalisasi kawasan Kota Lama kini dilakukan dengan memfungsikan gedung gedung tua menjadi tempat kegiatan perkantoran dan juga tempat kegiatan penunjang pariwisata di Kota Lama. Perkembangan revitalisasi kawasan cagar budaya Kota Lama sempat terhambat karena adanya masalah banjir rob dan penerangan jalan. Konsep waterfront untuk Kali Mberok menjadi salah satu solusi untuk mengatasi kendala revitalisasi Kota Lama dengan penambahan ruang terbuka hijau di pinggir Kali Mberok. Penerapan waterfront di Kali mberok Kota Lama akan memberikan dampak positif untuk mengurangi bangunan di pinggir sungai dan juga menambah penerangan jalan dengan penambahan ruang terbuka publik. Secara inovatif, kajian ini akan mengarah dan mengembangkan potensi yang dimiliki oleh Kali Mberok pada desain perancangan wisata tepian air Kali Mberok disekitar Kota Lama dengan penekanan konsep Waterfront.

The Impact of Tidal Flooding on Decreasing Land Values in the Areas of Tugu District, Semarang City

Semarang City as one of the areas on the north coast has a serious problem related to tidal flooding. The impact of this disaster has implications for changes in land use, a decrease in environmental quality and health, the emergence of slum settlements, a decrease in income and also a decrease in land value. This study aims to map the impact of tidal flooding on changes in land values based on the Land Value Zone Map (ZNT) and map land prices based on spatial data analysis. The study was carried out through spatial analysis by overlaying (join intersection) the 2014, 2016, 2018 and 2019 ZNT maps to determine changes in land value, while mapping land prices, especially in Mangunharjo Village, was based on land use maps, positive accessibility (road network) and negative accessibility (prone flood rob). The results of the study show that land which is permanently affected by tidal flooding and cannot be used anymore makes it a lost / destroyed land, while periodically inundated land has experienced a price decline in the range of Rp 100.000 – 200.000, -/m2. Meanwhile, the results of the study from the ZNT map for 2014 to 2019 show a very significant difference in price between zone 1 and a price increase of ± Rp 3.500.000; zone 2 price increase ± Rp 575.000, -, zone 3 at a price range of Rp 385.000, and zone 4 as the tidal flood prone zone only experienced an increase of Rp 250.000,-. In this context, the variable of tidal flooding vulnerability greatly affects the stagnation of land prices and even decreases in land prices, while the positive accessibility variable is the location of land on national and local roads that has experienced a very high price increase.

Physiological and Proteomic Analyses of Two Acanthus Species to Tidal Flooding Stress

The mangrove plant Acanthus ilicifolius and its relative, Acanthus mollis, have been previously proved to possess diverse pharmacological effects. Therefore, evaluating the differentially expressed proteins of these species under tidal flooding stress is essential to fully exploit and benefit from their medicinal values. The roots of A. ilicifolius and A. mollis were exposed to 6 h of flooding stress per day for 10 days. The dry weight, hydrogen peroxide (H2O2) content, anatomical characteristics, carbon and energy levels, and two-dimensional electrophoresis coupled with MALDI-TOF/TOF MS technology were used to reveal the divergent flooding resistant strategies. A. ilicifolius performed better under tidal flooding stress, which was reflected in the integrity of the morphological structure, more efficient use of carbon and energy, and a higher percentage of up-regulated proteins associated with carbon and energy metabolism. A. mollis could not survive in flooding conditions for a long time, as revealed by disrupting cell structures of the roots, less efficient use of carbon and energy, and a higher percentage of down-regulated proteins associated with carbon and energy metabolism. Energy provision and flux balance played a role in the flooding tolerance of A. ilicifolius and A. mollis.