Pengelolaan Kawasan Pesisir Timur Bangka Berbasis Adaptasi Gelombang Ekstrim dan Abrasi

Abstract

Wilayah pesisir merupakan wilayah peralihan lautan dan daratan. Wilayah ini memiliki karakteristik yang unik dengan potensi wilayah pesisir yang memberikan dampak positif terhadap peningkatan ekonomi masyarakat sekaligus memberikan tekanan terhadap sumberdaya pesisir. Wilayah ini juga rentan terhadap faktor alam seperti faktor hidrooseanografi, perubahan iklim, kenaikan muka laut, maupun aktivitas manusia yang merusak. Dampak ikutan seperti perendaman pesisir, perubahan proses ekologi di wilayah pesisir, intrusi air laut, serta peningkatan abrasi dan banjir. Analisis tingkat kerentanan pesisir sangat perlu dilakukan pada setiap kawasan pesisir untuk mengetahui kondisinya sebenarnya. Memahami kerentanan akibat faktor alam dan faktor manusia dapat menjadi dasar dalam membangun strategi adaptasi sehingga dapat menjadi input awal bagi perencanaan, pemanfaatan, pengawasan, dan pengendalian kawasan pesisir.

Penelitian ini memiliki tujuan dalam mengevaluasi perubahan garis pantai pesisir timur Bangka, menentukan tingkat kerentanan sosial, fisik, ekonomi dan lingkungan serta menyusun strategi pengelolaan kawasan perairan pesisir timur Bangka. Penelitian ini diselenggarakan pada bulan Agustus hingga Oktober 2021 di Kelurahan Matras, Desa Batu Belubang dan Desa Penyak. Evaluasi perubahan garis pantai dengan memanfaatkan Sistem Informasi Geospasial DSAS, metode EPR serta NSM. EPR yaitu nilai perubahan jarak yang dihitung antara 2 (dua) data yang berbeda waktunya sehingga menghasilkan data perubahan jarak terhadap waktu dalam meter/tahun. Perhitungan menggunakan NSM untuk menghitung jarak laju perubahan garis pantai dari waktu terlama hingga waktu terbaru dalam satuan meter. Analisis kerentanan sosial, fisik, ekonomi dan lingkungan menggunakan metode Multi Criteria Decision Analysis (MCDA) dan overlay (tumpang susun) perkalian antara skor dan bobot. Selanjutnya strategi pengelolaan wilayah perairan pesisir timur Bangka menggunakan analisis kapasitas, Sendai Framework for Disaster Risk Reduction (SFDRR), analisis risiko, analisis deskriptif serta analisis SWOT.

Hasil evaluasi sejak tahun 2001 sampai 2020 memperlihatkan adanya perubahan baik abrasi maupun akresi. Kawasan pesisir Kelurahan Matras menunjukkan terjadi abrasi dengan rata-rata -1,34 meter/tahun dan rata-rata -25,42 meter sepanjang 2,09 km garis pantai. Di kawasan ini terjadi akresi dengan rata-rata 2,42 meter/tahun dan rata-rata 45,93 meter. Pada Desa Batu Belubang terjadi abrasi dengan rata-rata -1,65 meter/tahun serta rata-rata -42,44 meter sepanjang 3,20 km garis pantai. Akresi menunjukkan perubahan garis pantai rata-rata 1,13 meter/tahun serta rata-rata 21,51 meter. Abrasi yang terjadi di Desa Penyak rata-rata -1,19 meter/tahun serta rata-rata -22,70 meter sepanjang 10,03 km garis pantai. Akresi menunjukkan perubahan garis pantai rata-rata 0,67 meter/tahun serta rata-rata 12,68 meter.

Indeks kerentanan sosial Kelurahan Matras memiliki nilai berkisar antara 0,000-0,603, indeks kerentanan fisik berkisar antara 0,000-0,084, indeks kerentanan ekonomi 0 dan indeks kerentanan lingkungan 0. Nilai Indeks kerentanan berkisar antara 0,000-0,656, dengan kelas kerentanan rendah-sedang, dengan dominan kelas kerentanan adalah sedang. Indeks kerentanan sosial Desa Batu Belubang memiliki nilai berkisar antara 0,000-0,631, indeks kerentanan fisik berkisar antara 0,000-0,326, indeks kerentanan ekonomi 0 dan indeks kerentanan lingkungan 0. Nilai Indeks kerentanan berkisar antara 0,000-0,835, dengan kelas kerentanan rendah, sedang dan tinggi, dengan dominan kelas kerentanan adalah rendah dan tinggi.

Indeks kerentanan sosial Desa Penyak memiliki nilai berkisar antara 0,000-0,617, indeks kerentanan fisik berkisar antara 0,000-0,545, indeks kerentanan ekonomi 0 dan indeks kerentanan lingkungan berkisar antara 0,000-0,946. Nilai Indeks kerentanan berkisar antara 0,000-1,000, dengan kelas kerentanan rendah, sedang dan tinggi, dengan dominan kelas kerentanan adalah rendah.

Strategi pengelolaan kawasan wilayah perairan pesisir timur Bangka dilakukan dengan adaptasi abrasi serta mitigasi. Adaptasi dilakukan terhadap wilayah yang telah terjadi abrasi, sedangkan mitigasi dilakukan terhadap wilayah yang belum terjadi abrasi. Adaptasi dimulai ketika timbulnya perasaan tidak nyaman akan lingkungan dan adanya usaha untuk mentoleransinya. Adaptasi oleh alam juga didukung oleh manusia untuk masa depan dalam menghadapi perubahan iklim. Strategi pengelolaan kawasan perairan pesisir timur Bangka dilakukan melalui peningkatan kapasitas daerah terhadap bencana khususnya pembuatan Rencana Penanggulangan Bencana (RPB) dan pembentukan Destana/Keltana.

The coastal area is a transitional area of the ocean and land. It has unique characteristics with the potential of coastal areas that have a positive impact on improving the community's economy as well as putting pressure on coastal resources. This areas is vulnerable to natural factors such as hydro-oceanographic, climate change, sea level rise, and destructive human activities. The side effects such as coastal submergence, changes in ecological processes in coastal areas, sea water intrusion, as well as increased abrasion and flooding. Analysis of the level of coastal vulnerability is very necessary to be carried out in each coastal area to find out the actual condition. Understanding vulnerability due to natural and human factors can be the basis for developing adaptation strategies. It can become initial inputs for planning, utilization, monitoring and control of coastal areas. This study aims to evaluate changes in the coastline of the east coast of Bangka, determine the level of social, physical, economic and environmental vulnerability as well as develop a management strategy for the coastal waters of the east of Bangka. This research was conducted from August to October 2021 in Matras Sub-districts, Batu Belubang Villages and Penyak Villages. Evaluation of shoreline changes using the DSAS Geospatial Information System, EPR method and NSM. EPR is the value of the change in distance calculated between 2 (two) data at different times so as to produce data on changes in distance to time in meters/year. The calculation uses NSM to calculate the distance of the coastline change rate from the oldest time to the newest time in meters. Analysis of social, physical, economic and environmental vulnerability using the Multi Criteria Decision Analysis (MCDA) and Overlay multiplication between scores and weights. Furthermore, the strategy for managing the eastern coastal waters of Bangka uses capacity analysis: Sendai Framework for Disaster Risk Reduction (SFDRR), risk analysis, descriptive analysis and SWOT analysis. The evaluation results of changes from 2001 until 2020 shows both, abrasion and accretion. The coastal area of Matras Village shows that there is abrasion with an average of -1.34 meters/year and an average of -25.42 meters along 2.09 km of coastline. In this area there is accretion with an average of 2.42 meters/year and an average of 45.93 meters. In Batu Belubang Village, abrasion occurs with an average of -1.65 meters/year and an average of -42.44 meters along 3.20 km of coastline. Accretion shows changes in shoreline at an average of 1.13 meters/year and an average of 21.51 meters. In Penyak Village, abrasion occurs at an average of -1.19 meters/year and an average of -22.70 meters along 10.03 km of coastline. Accretion shows an average change in coastline of 0.67 meters/year and an average of 12.68 meters. The social vulnerability index of Matras Village has a value ranging from 0.000 to 0.603, the physical vulnerability index ranges from 0.000-0.084, the economic vulnerability index 0 and the environmental vulnerability index 0. The vulnerability index value ranges from 0,000 to 0.656, with low and medium vulnerability classes, with the dominant vulnerability class being moderate. The social vulnerability index of Batu Belubang Village has a value ranging from 0.000 to 0.631, the physical vulnerability index ranges from 0.000-0.326, the economic vulnerability index 0 and the environmental vulnerability index 0. The vulnerability index value ranges from 0.000 to 0.835, with low, medium and high vulnerability classes, with low and high vulnerability classes dominant. The social vulnerability index of Penyak Village has a value ranging from 0.000 to 0.617, a physical vulnerability index ranging from 0.000 to 0.545, an economic vulnerability index 0 and an environmental vulnerability index ranging from 0.000 to 0.946. The vulnerability index value ranges from 0.000 to 1.000, with low, medium and high vulnerability classes, with the dominant vulnerability class being low. The strategy for the management of the eastern coastal waters of Bangka is carried out by adaptation to abrasion and mitigation. Adaptation is carried out on areas where abrasion has occurred, while mitigation is carried out on areas where abrasion has not occurred. Adaptation begins when there is an uncomfortable feeling about the environment and there is an attempt to tolerate it. Adaptation by nature is also supported by humans for the future in the face of climate change. The strategy for the management of the eastern coastal waters of Bangka is carried out through increasing the capacity of the region against disasters, in particular the preparation of a Disaster Management Plan (RPB) and the establishment of a Destana/Keltana.