Resilience and interaction of networks in ecology and economics (RESINEE)

Connections between individuals (persons, firms, cities, countries, plants, ecosystems) facilitate the exchange of resources, goods and information, but they also expose them to the threats and dangers. A network is said to be resilient if it is able to benefit from the connections and if it does not collapse under external shocks and perturbations. To study the resilience of networks we will consider the following issues: 1. Purpose of the network. The performance criteria for the network will depend on the purpose the network is meant to serve. The criteria will reflect the aims of a single entity controlling the links, for example, the owner of a computer network or the planner of land use. In other cases the criteria need to aggregate the interest of the different nodes, as in a banking system or an ecosystem. Finally, in other cases two opposing agents, such as a criminal organisation and the government or managers with different interests, will have conflicting interests, each one trying to maximise their own benefit. 2. Nature of the threat. In some situations threats are random, either because they are natural (e.g., weather and climate related, disease spreading) or because they reflect the technological uncertainties (e.g., the liquidity shocks reaching the banks because of the failure of a large borrower). Interesting situations arises when threats are designed by intelligent players whose goals are in conflict with the purpose of the network (e.g. computer hacker). A government agency monitoring terrorism poses a similar threat to a terrorist network. Finally, ecosystems function may collapse to a desert under increasing arid conditions (i.e., the system is attacked by lack of water) and climate change. 3. Decision making and agency of the nodes. In transport networks, there may be a single public agency defining the links and choosing the level of security, design and protection are both centralised. In other settings, such as computer networks, the design may be centralised, but the choice of protection and defense may be made at the level of nodes. There are situations in which the choice of links and the protection levels are made by the nodes in the network, e.g., individuals choosing the frequency of travel or vaccination. Finally, there are mixed situations: Banks choose the level of exposure in a financial network, but the bank supervisor may decide a maximum level of exposure, and in some cases they may choose to rewire the network by forcing mergers between financial institutions. Restoration of ecosystems involves external interventions but the individuals may also change their behaviour on their own. In this project, we will study how the above issues influence networks arising from concrete questions in economics and ecology. Underlying the project is the unifying picture of complex systems and, specifically, co-evolutionary models of interacting agents to advance the understanding of the emergence of resilience properties of networked systems. Both in ecology and economics networks evolve, and at the same time the interacting agents at the nodes dynamically adapt their strategic propensities (e.g. foraging patterns in ecological systems, or communication, management or risk diversification strategies in economics). Thus, structures at large scales emerge from processes at smaller scales, and tools from physics and mathematics of complex systems can be used to find similarities and differences among economic and ecological networks and the features contributing to their resilience. At a second stage these insights will help to identify suitable control and management mechanisms on the microscopic scale enhancing sustainability in both contexts. In making the connection between economics and ecology one may ultimately ask what can be learnt from the structure of natural network for the design of man-made structures.

Beneficiaries of this research will include (i) researchers in the immediate scientific area, (ii) researchers in the wider academic community, (iii) non-academic professional circles, and (iv) the general public. This Pathways to Impact document focuses on the potential impacts for non-academic professional circles, and the general public. (i) Researchers in the immediate scientific area: The immediate beneficiaries of the proposed research will be scientists working on complex systems, networks, economic modelling, modelling on ecology, statistical mechanics and the theory of stochastic processes. This is a very current and timely area of research, with a large and growing interdisciplinary community. These groups will benefit from the analytical and computational methods and tools we will develop, and from the results to be generated on network stability and resilience. Impact on these communities will be realised by publications in scientific journals across disciplines, by conference presentations and seminars, and by direct personal discussions. (ii) Researchers in the wider academic community: Beneficiaries in the wider academic community include applied economists and ecologists, who do not work on theoretical modelling themselves, but who interact with theoretical modellers on the one hand, and who liase with stakeholders and policy makers on the other hand. These beneficiaries will be reached by scientific publications in high impact journals, and by presentations at non-specialist academic meetings and conferences. We also anticipate that members of this community will attend seminars and research talks we will give. The project team itself includes members across disciplines, who all have contacts to this wider academic community. This will further enhance the impact. (iii) Non-academic professional circles: Beneficiaries will be policy makers, responsible for the design and regulation of economic networks (e.g. banking networks) and other decision makers. Stakeholders in the resilience community will benefit from the outputs of the project, as these can be used to design economic, social and infrastructure networks of enhanced resilience. Finally providers of IT networks and software products can ultimately profit from our research. Stakeholders such as the police, or other law enforcement agencies, may benefit from an enhanced analysis of social network structure, and may apply methods developed in this project to e.g. networks of terrorist or other criminal organisations. The second main stream of the project is concerned with ecosystem collapse and restoration. This has many applications outside the academic world, and is of direct importance for sustainable maintenance of natural resources, and ultimately for the quality of life in the UK. While one of our main applications will be the study of desertification in Iberia, ecosystem stability and diversity and the threats resulting from soil degradation and loss of hydrological connectivity are of crucial importance for the maintenance of the UK's natural resources as well. Beneficiaries of our research will include the Environment Agency, and ultimately decision and policy makers concerned with the natural resources in the UK, and with their sustainable exploitation and protection. (iv) General public The general public benefit in the long-term through enhanced stability of economic networks and from sustainable maintenance and restoration of ecological networks. These impacts are indirect and will be realised in the long term. In the short term we will engage with the public through outreach events and public communication of science. This will expose members of the public to the challenges and problems in this area, as well as to approaches to overcome these challenges.