Self-feedbacks determine the sustainability of human interventions in eco-social complex systems: Impacts on biodiversity and ecosystem health

Abstract

Several administrative polices have been implemented in order to reduce the negative impacts of fishing on natural ecosystems. Four eco-social models with different levels of complexity were constructed, which represent the seaweed harvest in central-northern Chile under two different regimes, Management and Exploitation Areas for Benthic Resources (MAEBRs) and Open Access Areas (OAAs). The dynamics of both regimes were analyzed using the following theoretical frameworks: (1) Loop Analysis, which allows the local stability or sustainability of the models and scenarios to be assessed; and (2) Hessian´s optimization procedure of a global fishery function (GFF) that represents each dynamics of each harvest. The results suggest that the current fishing dynamics in MAEBRs are not sustainable unless the market demand presents some type of control (i.e. taxes). Further, the results indicated that if the demand changes to a self-negative feedback (self-control) in MAEBRs, the stability is increased and, simultaneously, a relative maximum for the GFF is reached. Contrarily, the sustainability of the model/system representing the harvest (principally by cutting plants) in OAAs is not reached. The implementation of an “ecological” tax for intensive artisanal fisheries with low operational cost is proposed. The network analysis developed here is proposed as a general strategy for studying the effects of human interventions in marine coastal ecosystems under transient (short-term) dynamics.

Studying human–nature relationships through a network lens: A systematic review

“…Most studies falling into this category framed human–nature relations in the context of landscape management, with forest patches (Bodin, Robins, et al, 2016; Bodin & Tengö, 2012), vegetation clusters (Baggio & Hillis, 2018; Guerrero, Bodin, McAllister, & Wilson, 2015), local urban green spaces (Ernstson, Barthel, Andersson, & Borgström, 2010) or watershed units (Sayles & Baggio, 2017; Zhao, Wei, Wu, Lu, & Fu, 2018) representing ecological nodes managed by different human actors. A second major theme targeted fisheries, with fishers (as social nodes) engaging with their environment through the extraction of species from the ecosystem described as a food web (Barnes et al., 2019; Ortiz & Levins, 2017; Zador et al., 2017).…”

“…in Ortiz & Levins, 2017) for the analysis of links between fishers and respective markets (SS links), food web components (EE links) and between both realms through fisheries (SE links). With the aim of testing the stability of the SEN, the propagation of bottom‐up and top‐down perturbations was simulated through the elimination (Ortiz & Levins, 2017) or disturbance (Zador et al., 2017) of nodes to observe the effects on adjacent nodes and the entire network. The results provided insights on SES behaviour, for example, through the identification of the point at which a network breaks apart or the observation of (predicted) changes in strongly connected network components.…”

“…Rocchi et al., 2017) but also Type III (e.g. Ortiz & Levins, 2017; Zador et al., 2017) cases. Multi‐layer network approaches were found for Type I (e.g.…”

“…Barnes et al, 2019;Bodin, Robins, et al, 2016;Bodin & Tengö, 2012;Guerrero et al, 2015;Hamilton et al, 2019) The second major approach applied qualitative network modelling (including the Loop Analysis approach, e.g. in Ortiz & Levins, 2017) for the analysis of links between fishers and respective markets (SS links), food web components (EE links) and between both realms through fisheries (SE links). With the aim of testing the stability of the SEN, the propagation of bottom-up and top-down perturbations was simulated through the elimination (Ortiz & Levins, 2017) or disturbance (Zador et al, 2017) of nodes to observe the effects on adjacent nodes and the entire network.…”

Emergence of zoonoses such as COVID-19 reveals the need for health sciences to embrace an explicit eco-social conceptual framework of health and disease

“…This theory has been critiqued as placing too much focus on individual, cellular and subcellular levels at the expense of considering what was happening at population levels ( McMichael, 1999 ; Krieger, 1994 ; Susser and Susser, 1996 ; McMichael et al, 2015 ). As an alternative, various ecological or ecosocial theories have been proposed ( McMichael, 1999 ; Krieger, 1994 ; Susser and Susser, 1996 ; McMichael et al, 2015 ; Jones et al, 2017 ; Benach, 2020 ; Parkes et al, 2020 ; Shafiei et al, 2017 ; Ortiz and Levins, 2017 ; Hancock, 2015 ; Yang et al, 2015 ). Ecology is the formal study of the interdepencies between groups of organisms, populations, and species and their surroundings ( Susser and Susser, 1996 ).…”