No abstract

Aquaculture development is thriving to provide fish product demand. One-fifth of mangrove forest destruction in the coastal region is from aquaculture, where ninety percent occurred in South East Asia. The mangrove forest conversion for aquaculture development is also mirroring in Mahakam Delta which started in the early 1980s. In this paper, we examined the impact of aquaculture development in Mahakam Delta on the mangrove forest ecosystems using remote sensing. Thirty years of monitoring data were used using six Landsat images series (Landsat 5 and 8). The result found a massive development of aquaculture in the Mahakam Delta occurred in the late 1990s, in which 41% of mangrove forests converted into ponds. The unstable political situation in Indonesia and the decrease of rupiah exchange rate against the US dollar are the leading factors. Since the mid-2010s, aquaculture productivity has been declining and that many farmers decided to abandon their ponds. The condition made mangrove cover increase up to 4,000 hectares due to natural regeneration. Nevertheless, aquaculture ponds cover 54.8% of Mahakam Delta in 2020. To minimize the impact on the ecosystem, it needs to manage aquaculture sustainably with mangrove conservation.

Pandemi Covid-19 berdampak besar pada ketahanan pangan. Karantina wilayah dan pembatasan aktivitas sebagai langkah pencegahan penyebaran virus SARS-CoV-2 mendisrupsi sistem produksi dan distribusi pangan. Krisis pangan yang telah ada diperparah dengan kejadian pandemi Covid-19 menambah jumlah kasus kelaparan hingga 132 juta orang di seluruh dunia. Peningkatan ketahanan pangan tidak dapat menunggu hingga pandemi selesai. Paper ini membahas tentang kontribusi utama informasi geospasial dalam kaitannya dengan ketahanan pangan saat pandemi Covid-19. Dua hal utama yang membutuhkan informasi geospasial, dimana sumber makanan dan bagaimana cara mendapatkannya. Adopsi geospasial membantu dalam monitoring rantai suplai makanan dan mendukung penjualan makanan tanpa kontak (daring). Peningkatan penggunaan akses geospasial dalam aplikasi teknologi informasi mampu memberi dampak terhadap penanganan pandemi Covid-19. Kasus hasil panen yang tidak terjual dapat dihindarkan dengan adopsi informasi geospasial yang menghubungkan produsen dan konsumen. Selain itu, prediksi dampak perubahan iklim seperti kekeringan membantu penataan suplai makanan agar tidak terjadi krisis pangan.

Mangrove is one of the most intensive carbon sinks and plays a major role in the carbon cycle. However, the existence of mangrove is decreasing due to land use change that are not in accordance with its allocation, and disrupt the carbon cycle in the ecosystem. This study aims to estimate mangrove carbon stock using remote sensing technique in Tongke-tongke, South Sulawesi. Estimation using remote sensing usually has a low accuracy, therefore this research use multispectral (Landsat) and radar (PALSAR) sensor to increase the accuracy. Total carbon stocks in the study area based on model built for HH and HV polarization were 5662.85 ton and 6431.46 ton, respectively.

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Landslide is one type of slope movement, where the slope movement includes creep. Although creep movement does not have an impact on the risk of loss of life, this creep movement takes place constantly and  invisible which has an impact on economic losses. In this study, a time-series monitoring was carried out from 2018 to 2020 to see the movement of the slopes in the study area using the Multi-Temporal Interferometry Synthetic Aperture Radar (MTInSAR). A time series method from Sentinel 1A/B data, which includes Trangkil Sejahtera Housing (PTS), Soegijapranata Catholic University (UNIKA), and 17 August 1945 University (UNTAG) in Semarang City, Indonesia. The results of data processing indicate that there are slope movement in the target location, namely Trangkil Sejahtera and Selorejo Housing (southwest of UNIKA). Based on BPBD 2021 data, landslides occurred in the Trangkil Baru Housing Center (to the north of PTS) and the Garang River landslide channel west of Selorejo. This shows that there is a link between crawling in 2018-2020 and landslides in 2021. Although the use of satellite data has some drawbacks, the results can be taken into consideration in building an early warning system and reducing losses due to landslides.

The pressure on mangrove forest have been increasing due to abrasion and industrial development. Mangkang Kulon Sub-district as one coastal area in Semarang City experience loss of mangrove and coast itself due to abrasion from pond activities. We use Spectral Angle Mapper to classify species of mangrove in Mangkang Kulon. Spectral library was obtained from fieldwork using USB 4000. As the result, Spectral Angle Mapper successfully mapping distribution of species of mangrove in Mangkang Kulon. The area of mangrove in Mangkang Kulon is about 8.6 hectares or only 2% of Mangkang Kulon. Most of the mangrove in Mangkang Kulon is Bruguiera gymnorrhiza, followed by Rhizophora mucronata and Xylocarpus granatum. For future existence of mangrove ecosystem in Mangkang Kulon, several methods have been utilizing to improve extend and quality of mangrove.