TRANSIENT DYNAMICS IN RESERVOIRS AND REGULATED RIVERS
Predicting fish production trajectories in reservoirs:
Revisiting the Trophic Surge Hypothesis (TSH)
Revisiting the Trophic Surge Hypothesis (TSH)
We revisited and tested the “trophic surge hypothesis, TSH” which suggests that fish populations should demonstrate a hump-shaped pattern (i.e., non-equilibrium phase) after river impoundment (Turgeon et al. 2016).
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Conclusions regarding the status of fisheries in reservoirs can be short-sighted if formulated before the trophic equilibrium is reached |
Trophic surge or behavioural processes following impoundment?
We are now exploring - at a smaller spatial scale but with higher resolution data - if the TSH and associated metrics, can be predicted by species characteristics (i.e. age a first reproduction, trophic position, etc...) and by the location of sampling stations (distance from the dam, upstream or downstream). Here's a teaser (see figure beside). The duration of the trophic surge is positively correlated with fish trophic position. This will help designing and orienting impact assessment studies and mitigations measures related to hydroelectricity production |
Transient dynamics of ecological and biogeochemical processes in reservoirs
Following impoundment, reservoirs pass through a transitional phase where primary and secondary productivity, the accumulation of mercury in the food web, and GHG emissions increase and then decrease. These processes can have economic and social impacts, particularly on First Nations. Our understanding of the transient dynamics of these ecological and biogeochemical processes, the links between them, and their effects on reservoir ecosystem services and functions is still very limited. In her postdoc, Gabrielle will address these gaps in her postdoc (NSERC and Mitacs funded).
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Gabrielle Trottier | Postdoc
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