Towards Quantitatively Understanding the Complexity of Social-Ecological Systems—From Connection to Consilience

Abstract

The complexity of social-ecological systems (SES) is rooted in the outcomes of node activities connected by network topology. Thus far, in network dynamics research, the connectivity degree (CND), indicating how many nodes are connected to a given node, has been the dominant concept. However, connectivity focuses only on network topology, neglecting the crucial relation to node activities, and thereby leaving system outcomes largely unexplained. Inspired by the phenomenon of ''consensus of wills and coordination of activities'' often observed in disaster risk management, we propose a new concept of network characteristic, the consilience degree (CSD), aiming to measure the way in which network topology and node activities together contribute to system outcomes. The CSD captures the fact that nodes may assume different states that make their activities more or less compatible. Connecting two nodes with in/compatible states will lead to outcomes that are un/desirable from the perspective of the SES in question. We mathematically prove that the CSD is a generalized CND, and the CND is a special case of CSD. As a general, fundamental concept, the CSD can facilitate the development of a new framework of network properties, models, and theories that allows us to understand patterns of network behavior that cannot be explained in terms of connectivity alone. We further demonstrate that a co-evolutionary mechanism can naturally improve the CSD. Given the generality of co-evolution in SES, we argue that the CSD is an inherent attribute rather than an artificial concept, which underpins the fundamental importance of the CSD to the study of SES.

Disaster Risk Science: A Geographical Perspective and a Research Framework

“…Consilience is closely related to the vulnerability, resilience, and adaptability of disaster systems . Consilience can be computed by using consilience degree (Hu et al 2017). Simulation experiments have shown that a higher consilience degree indicates a greater capability to resist external shocks.…”

“…The globalization process has further highlighted the regional, interconnective, coupled, and complex features of disaster systems. The system dynamics and non-dynamics of disaster systems not only reveal the “node degree” behavior of their elements, but also their “consilience” behavior (Hu et al 2017 ). The consilience of disaster systems can reflect the differences of regional disaster systems not only in their mechanisms and processes, but also the integrated features of their structures and functions.…”

“…Consilience refers to four different synergetic principles in disaster management: (1) tolerance (cohesion), namely “united people can move mountains” (traditional Chinese saying, Ren Xin Qi, Tai Shan Yi ), “united people are strong” ( Qi Min Zhe Qiang ); (2) constraint (cohesion), namely “sacrifice a pawn to save a castle” ( Qi Zu Bao Ju ), “triumph comes when leaders and followers share the same goal” ( Shang Xia Tong Yu Zhe Sheng ); (3) amplification (joining force), that is, “more hands produce a stronger flame” ( Zhong Ren Shi Chai Huo Yan Gao ); and (4) diversification (joining force), that is, “ten chopsticks are stronger than one.” Consilience is closely related to the vulnerability, resilience, and adaptability of disaster systems (Shi, Wang, et al 2014 ). Consilience can be computed by using consilience degree (Hu et al 2017 ). Simulation experiments have shown that a higher consilience degree indicates a greater capability to resist external shocks.…”

“…Simulation experiments have shown that a higher consilience degree indicates a greater capability to resist external shocks. Optimization over consilience degree can substantially increase DRR resources utilization efficiency and effectiveness (Hu et al 2017 ).…”

“…The Chinese government is promoting holistic national security, that is, an effort to strive for people-centered and coordinated development, prevention-centered and integrated DRR, response with legal and S&T support, and private-sector participation under government leadership. In an era of globalization, more comparative studies are needed to understand how to establish a brand-new disaster risk management system (Hu et al 2017 ).…”