Network resilience

Many systems on our planet are known to shift abruptly and irreversibly from one state to another when they are forced across a "tipping point," such as mass extinctions in ecological networks, cascading failures in infrastructure systems, and social convention changes in human and animal networks. Such a regime shift demonstrates a system's resilience that characterizes the ability of a system to adjust its activity to retain its basic functionality in the face of internal disturbances or external environmental changes. In the past 50 years, attention was almost exclusively given to low dimensional systems and calibration of their resilience functions and indicators of early warning signals without considerations for the interactions between the components. Only in recent years, taking advantages of the network theory and lavish real data sets, network scientists have directed their interest to the real-world complex networked multidimensional systems and their resilience function and early warning indicators. This report is devoted to a comprehensive review of resilience function and regime shift of complex systems in different domains, such as ecology, biology, social systems and infrastructure. We cover the related research about empirical observations, experimental studies, mathematical modeling, and theoretical analysis. We also discuss some ambiguous definitions, such as robustness, resilience, and stability.Comment: Review chapter

The Yamanote Loop: Unifying Rail Transportation and Disaster Resilience in Tokyo

As climate change and population growth persist, and as the world rapidly urbanizes, major cities across the globe will face unprecedented strains. The risk of devastating impact from natural disasters increases in areas with a growing concentration of people. Megacities in Asia are the most at-risk of natural disasters, given their geographic location and high population density. With the highest projected population growth in the world, Asian cities must quickly expand and adapt their existing infrastructure to accommodate the transforming global conditions. A remarkable anomaly amongst Asian megacities, Tokyo, Japan is effectively adapting to its earthquake-prone environment. Within the last century, Japan has implemented seismically reinforced buildings and educational resources for earthquake preparedness. Amongst other technological innovations, investments in railway transportation have permitted major cities like Tokyo to expand and adjust according to its changing needs. The Yamanote Line is the primary commuter rail line in Tokyo. Its antecedent originated in 1885 and has since undergone significant changes to evolve into the highly sophisticated system it is today. By examining the evolvement of the Yamanote line from its conception and into the 21st century, this study explores the correlation between local rail transportation networks and their city’s resilience to natural disasters. A descriptive analysis aligned with four constructs of transportation resilience—robustness, redundancy, resourcefulness, and rapidity—observes instances in which the Yamanote line potentially strengthens Tokyo’s comprehensive disaster preparedness. The following study intentionally circumvents normative-prescriptive conclusions and focuses primarily on the impact of transformations of railway transportation on its broader urban context over time respective to disaster resilience and with consideration of other relative factors

Sustainability and Replicability of Multiple-Use Water Systems (MUS)

The concept of multiple-use water services and systems (MUS) has received increasingattention in international water and development fora and has emerged as a promising wayto enhance the social and gender equity and productivity of water systems designed forsingle use, e.g. for irrigation or water supply. In Nepal, several MUS models have beenpiloted and implemented for more than a decade by the International DevelopmentEnterprises (iDE) and a few other development organizations. Whereas the short-termbenefits of these systems on gender relationships, women's empowerment, nutrition andhealth have been documented, the sustainability and resilience of these systems has not yetbeen analyzed. The latter is the focus of the research study presented in this report, whichwas conducted by the International Water Management Institute (IWMI) in Western Nepalas part of the USAID-funded Market Access and Water Technology for Women (MAWTW)project

Robustness of animal production systems : concept and application to practical cases

A concept and method are developed and applied to improve robustness in animal production

Merging DNA metabarcoding and ecological network analysis to understand and build resilient terrestrial ecosystems

Summary 1. Significant advances in both mathematical and molecular approaches in ecology offer unprecedented opportunities to describe and understand ecosystem functioning. Ecological networks describe interactions between species, the underlying structure of communities and the function and stability of ecosystems. They provide the ability to assess the robustness of complex ecological communities to species loss, as well as a novel way of guiding restoration. However, empirically quantifying the interactions between entire communities remains a significant challenge. 2. Concomitantly, advances in DNA sequencing technologies are resolving previously intractable questions in functional and taxonomic biodiversity and provide enormous potential to determine hitherto difficult to observe species interactions. Combining DNA metabarcoding approaches with ecological network analysis presents important new opportunities for understanding large-scale ecological and evolutionary processes, as well as providing powerful tools for building ecosystems that are resilient to environmental change. 3. We propose a novel ‘nested tagging’ metabarcoding approach for the rapid construction of large, phylogenetically structured species-interaction networks. Taking tree–insect–parasitoid ecological networks as an illustration, we show how measures of network robustness, constructed using DNA metabarcoding, can be used to determine the consequences of tree species loss within forests, and forest habitat loss within wider landscapes. By determining which species and habitats are important to network integrity, we propose new directions for forest management. 4. Merging metabarcoding with ecological network analysis provides a revolutionary opportunity to construct some of the largest, phylogenetically structured species-interaction networks to date, providing new ways to: (i) monitor biodiversity and ecosystem functioning; (ii) assess the robustness of interacting communities to species loss; and (iii) build ecosystems that are more resilient to environmental change