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Hengeveld, G. M.

Publications and source records attributed to Hengeveld, G. M..

2 recordsLinked to original sources

In the face of competition, imperfect knowledge can lead to sustainable exploitation of a shared resource.

Overexploitation of a shared resource is a frequent phenomenon among groups of selfish consumers, known as the tragedy of the commons. To avoid "self-damage through self-interest", humans may either defend exclusive access to resources, or collectively adopt advanced cooperative behaviour and carefully designed spatial harvesting strategies to exploit a shared resource sustainably. However, why do many non-human species that are neither social nor territorial also appear to avoid overexploiting resources? This study shows that, even under highly competitive scenarios, cooperation is not necessary to sustainably exploit shared resources if individuals have imperfect knowledge about the distribution of those resources. Poorly informed individuals are more likely to inadvertently exploit resources in peripheral habitats, which may allow for higher resource renewal in the nearby and low-cost habitats, enhancing the sustainability of resource use. As a result, those consumers can achieve a long-term yield that approaches that of cooperative consumers and is higher than omniscient consumers. Ironically, while there might be an evolutionary drive for individuals to make well-informed decisions, consumers of shared resources may be collectively more prosperous when they make decisions based on less information. These findings might explain why apparently sub-optimal consumer behaviour appears so prevalent in nature.

ecology↗

Consequences of alternative stable states for short-term model-based control of cyanobacterial blooms

Cyanobacteria can form dense blooms in eutrophic lakes that can be toxic to humans and other animals and harmful to the ecosystems functioning. While better nutrient management is generally considered the long-term solution to this problem, short-term mitigation efforts (e.g., flushing, algaecides, flocculants) are becoming increasingly necessary to safeguard water quality and the ecosystem services it provides. Here, we explore potential model-based management strategies for these short-term mitigation efforts. We focus on the case where blooms are linked to the existence of alternative stable states, such that, under the same conditions but depending on the past, a lake may be dominated either by cyanobacteria (causing a harmful algal bloom) or by green algae and macrophytes in a clear water state. Changing conditions may cause the favourable clear water state to disappear through a tipping point, causing the lake to switch rapidly to the turbid cyanobacteria state. At the same time, it may take considerable effort to undo this tipping and return to the favourable state. We identify four different strategies for bloom mitigation in this scenario: Doing nothing, reacting to a bloom, resetting the lake at a later point, and preventing the bloom. We explore the different requirements for these strategies along with their associated cost profiles. We also investigate the effect of transition times from one state to another on the efficacy and costs of different strategies.

ecology↗