Sanctioned Quotas Versus Information Provisioning for Community Wildlife Conservation in Zimbabwe: A Framed Field Experiment Approach

We investigate the behavioural responses of natural common-pool resource users to three policy interventions—sanctioned quotas, information provisioning, and a combination of both. We focus on situations in which users find utility in multiple resources (pastures and wild animal stocks) that all stem from the same ecosystem with complex dynamics, and management could trigger a regime shift, drastically altering resource regrowth. We performed a framed field experiment with 384 villagers from communities managing common-pool wildlife in Zimbabwe. We find that user groups are likely to manage these natural resources more efficiently when facing a policy intervention (either a sanctioned quota, receiving information about a drastic drop in the stocks’ regrowth below a threshold, or a combination of both), compared to groups facing no intervention. A sanctioned quota is likely to perform better than providing information about the existence of a threshold. However, having information about the threshold also leads to higher efficiency and fewer depletion cases, compared to a situation without any intervention. The main contribution of this study is to provide insights that can inform policymakers and development practitioners about the performance of concrete and feasible policy interventions for community wildlife conservation in Southern Africa

Ultrafast Laser-Based Spectroscopy and Sensing: Applications in LIBS, CARS, and THz Spectroscopy

Ultrafast pulsed lasers find application in a range of spectroscopy and sensing techniques including laser induced breakdown spectroscopy (LIBS), coherent Raman spectroscopy, and terahertz (THz) spectroscopy. Whether based on absorption or emission processes, the characteristics of these techniques are heavily influenced by the use of ultrafast pulses in the signal generation process. Depending on the energy of the pulses used, the essential laser interaction process can primarily involve lattice vibrations, molecular rotations, or a combination of excited states produced by laser heating. While some of these techniques are currently confined to sensing at close ranges, others can be implemented for remote spectroscopic sensing owing principally to the laser pulse duration. We present a review of ultrafast laser-based spectroscopy techniques and discuss the use of these techniques to current and potential chemical and environmental sensing applications

Human Behaviour in Social-Ecological Systems : Insights from economic experiments and agent-based modelling

Progress towards sustainability requires changes in our individual and collective behaviour. Yet, our fundamental understanding of behaviour in relation to environmental change remains severely limited. In particular, little attention has been given to how individual and collective behaviours respond to, and are shaped by, non-linear environmental change (such as ‘regime shifts’) and its inherent uncertainties. The thesis makes two main contributions to the literature: 1) it provides one of the first accounts of human behaviour and collective action in relation to ecological regime shifts and associated uncertainties; and 2) extends the incipient behavioural common-pool resource literature that acknowledges social-ecological dynamics and ecological complexity. The overarching aim of this thesis is to further advance an empirically grounded understanding of human behaviour in social-ecological systems. In particular, the thesis attempts to unravel critical social-ecological factors and mechanisms for the sustainability of common-pool resources. This is especially relevant for contexts in which livelihoods can be more directly threatened by regime shifts. The following methods are applied: behavioural economic experiments in the lab (with students; Papers I and II) and in the field (with small-scale fishers from four different communities in the Colombian Caribbean; Paper III), and agent-based modelling empirically informed by a subset of the lab experiments (Paper IV). Paper I tests the effect of an endogenously driven regime shift on the emergence of cooperation and sustainable resource use. Paper II tests the effect of different risk levels of such a regime shift. The regime shift in both papers has negative consequences for the productivity of the shared resource. Paper III assesses the effect of different degrees of uncertainty about a climate-induced threshold in stock dynamics on the exploitation patterns; as well as the role of social and ecological local context. Paper IV explores critical individual-level factors and processes affecting the simultaneous emergence of collective action and sustainable resource use. Results cumulatively suggest that existing scientific knowledge indicating the potential for ecological regime shifts should be communicated to affected local communities, including the remaining uncertainties, as this information can encourage collective action for sustainable resource use. Results also highlight the critical role of ecological knowledge, knowledge-sharing, perceived ecological uncertainties, and the role local contexts play for sustainable outcomes. This thesis enriches the literature on social-ecological systems by demonstrating how a behavioural experimental approach can contribute new insights relevant for sustainability. Overall, these insights indicate that, given the opportunity and the willingness of people to come together, share knowledge, exchange ideas, and build trust, potential ecological crises can encourage collective action, and uncertainties can be turned into opportunities for dealing with change in constructive ways. This provides a hopeful outlook in the face of escalating environmental change and inherent uncertainties.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.</p

Identifying factors influencing exploitation strategies and cooperation in commons dilemmas under threshold uncertainty : Evidence from a laboratory experiment

I employ a laboratory experiment to examine behavior of user groups in commons dilemmas under uncertainty about a potential abrupt change in the resource renewal rate (threshold uncertainty). In this experiment, 87 subjects, randomly assigned to groups of three to four subjects, take anonymous individual harvest decisions over an unknown number of rounds while communication is allowed. Threshold uncertainty is captured in the experimental design as follows: Subjects are shown the resource dynamics of two different scenarios. While the resource dynamics of scenario A follows a logistic growth function, the regeneration rate of scenario B drops drastically below a certain resource stock size, or threshold. Subjects know they either play scenario A or B (with equal probability), but they do not know which. The primary finding is that user groups respond to threshold uncertainty in a precautionary manner. This contrasts previous experimental evidence that environmental uncertainty increases exploitation but points to recent findings in the field arguing that a threat can trigger cooperative behavior resulting in less cases of over-exploitation. The certainty of the threat, however, seems to matter as well as other variables, like if cheating occurred or not. As predicted, groups with higher trust levels are more likely to cooperate

Human Behaviour in Social-Ecological Systems : Insights from economic experiments and agent-based modelling

Progress towards sustainability requires changes in our individual and collective behaviour. Yet, our fundamental understanding of behaviour in relation to environmental change remains severely limited. In particular, little attention has been given to how individual and collective behaviours respond to, and are shaped by, non-linear environmental change (such as ‘regime shifts’) and its inherent uncertainties. The thesis makes two main contributions to the literature: 1) it provides one of the first accounts of human behaviour and collective action in relation to ecological regime shifts and associated uncertainties; and 2) extends the incipient behavioural common-pool resource literature that acknowledges social-ecological dynamics and ecological complexity. The overarching aim of this thesis is to further advance an empirically grounded understanding of human behaviour in social-ecological systems. In particular, the thesis attempts to unravel critical social-ecological factors and mechanisms for the sustainability of common-pool resources. This is especially relevant for contexts in which livelihoods can be more directly threatened by regime shifts. The following methods are applied: behavioural economic experiments in the lab (with students; Papers I and II) and in the field (with small-scale fishers from four different communities in the Colombian Caribbean; Paper III), and agent-based modelling empirically informed by a subset of the lab experiments (Paper IV). Paper I tests the effect of an endogenously driven regime shift on the emergence of cooperation and sustainable resource use. Paper II tests the effect of different risk levels of such a regime shift. The regime shift in both papers has negative consequences for the productivity of the shared resource. Paper III assesses the effect of different degrees of uncertainty about a climate-induced threshold in stock dynamics on the exploitation patterns; as well as the role of social and ecological local context. Paper IV explores critical individual-level factors and processes affecting the simultaneous emergence of collective action and sustainable resource use. Results cumulatively suggest that existing scientific knowledge indicating the potential for ecological regime shifts should be communicated to affected local communities, including the remaining uncertainties, as this information can encourage collective action for sustainable resource use. Results also highlight the critical role of ecological knowledge, knowledge-sharing, perceived ecological uncertainties, and the role local contexts play for sustainable outcomes. This thesis enriches the literature on social-ecological systems by demonstrating how a behavioural experimental approach can contribute new insights relevant for sustainability. Overall, these insights indicate that, given the opportunity and the willingness of people to come together, share knowledge, exchange ideas, and build trust, potential ecological crises can encourage collective action, and uncertainties can be turned into opportunities for dealing with change in constructive ways. This provides a hopeful outlook in the face of escalating environmental change and inherent uncertainties.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.</p

Potential Disasters can Turn the Tragedy into Success

This paper presents a novel experimental design that allows testing how users of a common-pool resource respond to an endogenously driven drastic drop in the supply of the resource. We show that user groups will manage a resource more efficiently when confronted with such a non-concave resource growth function, compared to groups facing a logistic growth function. Even among cooperative groups there is a significant behavioral difference, although theory predicts there should not be. We argue that effectiveness of communication is endogenous to the problem; the threat of reaching a critical tipping point, beyond which the growth rate will drop drastically, triggers more effective communication within the group, enabling stronger commitment for cooperation and more knowledge sharing, which together explains the results. We argue that the insights generated by this study can be seen as one of many, but nevertheless important, contributions towards an increased understanding of the interactions between human behavior and the environment in common-pool resource systems

Collective action and the risk of ecosystem regime shifts: insights from a laboratory experiment

Ecosystems can undergo regime shifts that potentially lead to a substantial decrease in the availability of provisioning ecosystem services. Recent research suggests that the frequency and intensity of regime shifts increase with growing anthropogenic pressure, so understanding the underlying social-ecological dynamics is crucial, particularly in contexts where livelihoods depend heavily on local ecosystem services. In such settings, ecosystem services are often derived from common-pool resources. The limited capacity to predict regime shifts is a major challenge for common-pool resource management, as well as for systematic empirical analysis of individual and group behavior, because of the need for extensive preshift and postshift data. Unsurprisingly, current knowledge is mostly based on theoretical models. We examine behavioral group responses to a latent endogenously driven regime shift in a laboratory experiment. If the group exploited the common-pool resource beyond a certain threshold level, its renewal rate dropped drastically. To determine how the risk of such a latent shift affects resource management and collective action, we compared four experimental treatments in which groups were faced with a latent shift with different probability levels (0.1, 0.5, 0.9, 1.0). Our results suggest that different probability levels do not make people more or less likely to exploit the resource beyond its critical potential threshold. However, when the likelihood of the latent shift is certain or high, people appear more prone to agree initially on a common exploitation strategy, which in turn is a predictor for averting the latent shift. Moreover, risk appears to have a positive effect on collective action, but the magnitude of this effect is influenced by how risk and probabilities are communicated and perceived