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The microseismic monitoring technique has great advantages on identifying the location, extent and the mechanism of damage process occurring in rock mass. This study aims to analyze distribution characteristics and the evolution law of excavation damage zone of surrounding rock based on microseismic monitoring data.

In situ test using microseismic monitoring technique is carried out in the large-span transition tunnel of Badaling Great Wall Station of Beijing-Zhangjiakou high-speed railway. An intelligent microseismic monitoring system is built with symmetry monitoring point layout both on the mountain surface and inside the tunnel to achieve three-dimensional and all-round monitoring results.

Microseismic events can be divided into high density area, medium density area and low density area according to the density distribution of microseismic events. The positions where the cumulative distribution frequencies of microseismic events are 60 and 80% are identified as the boundaries between high and medium density areas and between medium and low density areas, respectively. The high density area of microseismic events is regarded as the high excavation damage zone of surrounding rock, which is affected by the grade of surrounding rock and the span of tunnel. The prediction formulas for the depth of high excavation damage zone of surrounding rock at different tunnel positions are given considering these two parameters. The scale of the average moment magnitude parameters of microseismic events is adopted to describe the damage degree of surrounding rock. The strong positive correlation and multistage characteristics between the depth of excavation damage zone and deformation of surrounding rock are revealed. Based on the depth of high excavation damage zone of surrounding rock, the prestressed anchor cable (rod) is designed, and the safety of anchor cable (rod) design parameters is verified by the deformation results of surrounding rock.

The research provides a new method to predict the surrounding rock damage zone of large-span tunnel and also provides a reference basis for design parameters of prestressed anchor cable (rod).

Agricultural systems in Mekong Delta have transformed to cope with climate change. Various researches pointed out that integrated agriculture-aquaculture (IAA) farming systems (i.e., rice-shrimp, rice-fish…) emerged as potential climate adaptive practices. However, limited studies are attempting to assess the sustainability of these agricultural practices. Therefore, it is essential to assess whether or not these systems will be sustainable in the context of climate change and what can be done to make it sustainable. The present study conducted the sustainability assessment of the rice-shrimp system to identify potential areas for improvement as well as policy implication to increase resilience and adaptation of coastal IAA system which could contribute to the understanding of other coastal agricultural deltas around the globe.

This study used a quantitative approach including the assessment protocol of van Asselt et al. (2014), the assessment framework of Vanloon et al. (2005), and the MCA methodology to flexibly and holistically assess the sustainability level of agricultural systems.

Results concluded that rice-shrimp systems have the potential to improve livelihood, food security, and adaptation of coastal farmers. Major improvements should be considered for productivity, efficiency, and equity themes, while minor improvements can be made for stability, durability, and compatibility themes.

This research could be used as a guideline for sustainability assessment in a context-specific case study of IAA, which showed a potential for the application of other climate-smart IAAs in similar contexts around the globe.

This paper aims to identify key factors for a contextualised Systemic Risk Governance (SRG) framework and subsequently explore how systemic risks can be managed and how local institutional mechanisms can be tweaked to deal with the complex Indonesian risk landscape.

Using a case study from Palu triple-disasters in Central Sulawesi, Indonesia, the authors demonstrate how inland earthquakes in 2018 created cascading secondary hazards, namely tsunamis, liquefactions and landslides, caused unprecedented disasters for the communities and the nation. A qualitative analysis was conducted using the data collected through a long-term observation since 2002.

The authors argue that Indonesia has yet to incorporate an SRG approach in its responses to the Palu triple-disasters. Political will is required to adopt more appropriate risk governance modes that promote the systemic risk paradigm. Change needs to occur incrementally through hybrid governance arrangements ranging from formal/informal methods to self- and horizontal and vertical modes of governance deemed more realistic and feasible. The authors recommend that this be done by focusing on productive transition and local transformation.

There is growing awareness and recognition of the importance of systemic and cascading risks in disaster risk studies. However, there are still gaps between research, policy and practice. The current progress of disaster risk governance is not sufficient to achieve the Sendai Framework for Disaster Risk Reduction (2015–2030) unless there is an effective governing system in place at the local level that allow actors and institutions to simultaneously manage the interplays of multi-hazards, multi-temporal, multi-dimensions of vulnerabilities and residual risks. This paper contributes to these knowledge gaps.