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An Introduction to Hydrophonics and Controlled Environment.
As the demand for hydroelectricity progresses worldwide, small hydropower operators are increasingly examining the feasibility of using existing infrastructure e. Such flexible production causes short-term discharge fluctuations hydropeaking in downstream reaches with potential adverse effects for the sensitive fauna and flora in alpine streams.
In an experimental field study on a previously unregulated section of the upper Rhone River Switzerlandwe measured density and composition of macroinvertebrate drift in two habitats riffle, pool following a minute hydropeaking wave.
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Results from the kick sampling showed that benthic macroinvertebrate abundance and composition did not significantly change between the experimental peaks. There were habitat specific reactions Controller macroinvertebrate drift to hydropeaking, with the pool experiencing more pronounced drift abundances than the riffle. Overall, drift abundance click not significantly correlated with recovery time, but results indicate taxa-specific differences.
This research advocates for the importance Cpntrolled completing more in-situ field experiments in order https://amazonia.fiocruz.br/scdp/essay/mormon-bank-utah/nursing-theories-and-their-importance-in-nursing.php better understand the ecological impact of flexible power production in small hydropower plants. Recent growth in energy demand has accelerated human reliance on hydropower, stimulating an increase in construction of new hydropower plants around the globe Zarfl et al.
Hydropower is now the leading form of market-based renewable energy Jager et al. There is, however, limited growth potential for new hydropower operations in Envkronment parts of the world, and the negative ecological impacts of large hydropower plants are well known Poff et al. In light of this, much attention is being focused on the endorsement of small hydropower plants SHPs; Anderson et al. Because An Introduction to Hydrophonics and Controlled Environment their size, there is a perception that SHPs have fewer adverse ecological impacts than large hydropower plants Kibler and Tullos, ; Anderson et al. In reality, the ecological footprint of SHPs per megawatt of power produced may actually be significantly higher than that of the large hydropower plants See more et al.
Research towards understanding the ecological impact is gaining momentum as there is a growing number of operational and prospective SHPs Anderson et al.
SHPs are typically operated as run-of-the-river schemes allowing for continuous production of power. Increasingly, SHP operators are evaluating opportunities to use existing infrastructure e. As a consequence of varying power production with demand, downstream rivers experience drastic daily and sub-daily fluctuations in streamflow and stage, a phenomenon widely known as hydropeaking e.
Original Research ARTICLE
Because of the heterogeneous nature of hydropeaking and small hydropower plant design and operation, considerable variability exists in peak frequency, magnitude, duration, and potential to optimize operations with respect to the natural environment. In recent decades, research focused on characterizing and quantifying the complex spatial and temporal impacts hydropeaking has on aquatic habitats, organisms, and ecosystem processes. A large variety of effects has been observed such as stranding of fish Bell et al.
Benthic macroinvertebrates re colonize via drift during their aquatic larval stages Robinson et al.]
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