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An earthquake with a magnitude of 7.4 in Palu City and Donggala District in Central Sulawesi Province on September 28, 2018 has caused a liquefaction disaster. Basically liquefaction can occur in earthquake prone areas, shallow phreatic depth and poorly consolidated soil. This study attempts to examine the relationship between phreatic depth and the probability of liquefaction. The research method is an analog and numerical relation model, by combining the aquifer system model and groundwater geographic information system with landuse patterns in areas affected by liquefaction disasters. This method is described in Spatial and Environmental Analysis, which is supported by the use of satellite imagery and the analysis process with the Arc View Gis 3.3 program. The results showed that there was an influence between rainfall on the spatial distribution of phreatic depth, with the average rainfall in the Palu area being 68.74 mm / month and the depth of phreatic level ranged from medium (2.5 - 7.0 meters from ground level) - shallow (<2.5 meters from ground level). Based on the phreatic depth of the Palu groundwater basin, the chances for liquefaction are in the medium to high zone class.

After the 22 December 2018 flank collapse, series of hydrothermal, phreatomagmatic, and effusive eruptions occurred and changed the morphology of Anak Krakatau. The ejected volcanic materials enlarge and increase the elevation of the west flank, which may indicate a reconstruction phase of the Anak Krakatau edifice. Here, we investigated the morphological changes of Anak Krakatau between 2019 and 2020 by using drone SfM photogrammetry, Sentinel and Pleiades satellite imageries, and fieldworks photograph data. The result shows volcaniclastic deposit due to the hydrothermal and/or phreatomagmatic eruptions that covered 0.08 km2 around an active crater lake at Anak Krakatau between February and January 2020. The large phreatomagmatic and effusive eruptions on 10 April 2020 produced tephra and lava flow deposits that significantly changed the morphology of Anak Krakatau. The deposit of tephra covered 0.815 km2 at the north – northwest flanks of Anak Krakatau, while the lava flow emplaced 0.2 km2 and elongated around 742 m from the pre-existing crater lake to the west shoreline of Anak Krakatau. The lava flow has a blocky surface and highly fractured that possibly formed due to compression – extension stresses during lava flow emplacement. The emplacement of the massive lava flow at the pre-existing crater lake may change the future eruption style at Anak Krakatau, which was previously dominated by hydrovolcanism activities, such as hydrothermal and phreatomagmatic events.

In the last eight years (2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016), some areas in the northern part of Pekalongan have been experiencing coastal inundation. There have been social, economic and physical disruptions caused by coastal inundation particularly on built environments, paddy fields, and fishpond. The capacity of these areas to provide support for community livelihood has decreased significantly. This accumulative environmental change leads to the emergence of vulnerable regions which are characterized by limited social and ecological capacity to respond hazards. In order to enhance the social-ecological resilience, it is necessary to identify how the community has elevated their capacity and improved their livelihood. This paper presents empirical evidence of various pathways on how the community has transformed their capacity to respond to the changing environment due to coastal inundation. Following case study approach, this paper explores how the community has learned from their experiences, knowledge, and efforts from the past, and transformed them into a better understanding to cope with, to adapt to, and to become resilient from coastal inundation. The research applied in-depth interviews involving key persons selected through purposive and snowballing samplings. They represented the most capable person in each sub-district whose important data and information related to coastal inundation at the individual, household, and community organization levels belong to. The scope of area observation was limited to six sub-districts adjacent to the coast in the North Pekalongan District. The results showed that social-ecological resilience is likely to enhance in a community with flexible networking building capability. Such networking is beneficial to spreading out the important information, novel knowledge and practical tools and solutions to the community. These are the key elements for new transformative pathways. However, there remain various community capacities with different achievements on transformative pathways necessary to the future empowerment initiatives. Only a few communities in Kandang Panjang Sub-district who have performed a short-term resilience due to their awareness on establishing social networking and several actions on environmental quality improvements.Keywords: coastal inundation, community capacity, livelihood, social-ecological resilience, transformative pathways Abstrak: Dalam delapan tahun terakhir (2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016), bagian utara Kota Pekalongan terpapar oleh genangan pesisir (rob). Banyak gangguan sosial, ekonomi dan fisik yang terjadi akibat genangan pesisir tersebut terutama pada lingkungan terbangun, sawah dan tambak. Kapasitas wilayah untuk mendukung penghidupan masyarakat menurun secara signifikan. Akumulasi perubahan lingkungan yang terjadi mengakibatkan munculnya kerentanan wilayah yang dicirikan oleh keterbatasan kapasitas sosial dan ekologi terkait bahaya yang terjadi. Guna penguatan ketahanan sosial ekol...