Freshwater Research News (FRN) aims to bring the results of current global freshwater research to a wider audience. Using non-specialist language as far as possible, FRN draws on over 60 scientific journals to summarise the background and significance of recent research findings, giving special attention to novel ideas, new interpretations, and interdisciplinary connections involving the freshwater environment. The… [Read more…]
March 27, 2012
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The key role played by migrating salmon in transporting nutrients, organic matter and energy to upstream spawning areas has been well documented. Several studies have described how nutrient subsidies derived from salmon have a strong impact on the structure of aquatic food webs, through bottom-up increases in primary and then secondary productivity. However, a new… [Read more…]
March 27, 2012
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To understand why aquatic communities are structured the way they are, it’s necessary to assess the importance of broadscale regional factors relative to more local influences. Landscape geology can have profound effects on the physical and chemical environments of aquatic systems, and thus the species composition of biological communities. The PreCambrian Shield covers most of… [Read more…]
March 27, 2012
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Groynes are commonly used to protect riverbanks from erosion by deflecting the flow towards the middle of the stream. Flow separation and recirculation patterns downstream of a groyne tend to create scour holes. Although scour holes can provide important habitats for aquatic organisms, especially in disturbed streams and during floods, few studies have recorded how… [Read more…]
March 27, 2012
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Horsehair worms are parasites of terrestrial insects such as crickets and grasshoppers, entering their hosts as microscopic larvae and growing into adults that can take up most of the host’s body cavity. In some cases the presence of the parasite leads to erratic behaviour by the host, which causes it to jump into a stream,… [Read more…]
March 27, 2012
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When exposed to predator pressure, many animal prey species are able to modify their behavior or body form to reduce their vulnerability to attack. These responses are triggered by chemicals released by predators. The adoption of improved defences (e.g., longer protective spines) by prey species not only tends to reduce the feeding success and growth… [Read more…]
March 27, 2012
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Several field studies have shown that the regulation of rivers by dam construction can have dramatic effects on the form of the channel and downstream bankside vegetation. Observed changes attributed to damming include declines in habitat diversity, decreases in native plant species and invasions by exotics, but such changes have been difficult to anticipate with… [Read more…]
March 27, 2012
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Modern water management routinely involves dealing with the often diverse views of local stakeholders, especially those with close connections to locations where management interventions are proposed or have already occurred. Because many of the attitudes and beliefs of stakeholders depend strongly on the spatial context, a better understanding of the various meanings that emerge from… [Read more…]
March 27, 2012
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Although lakes are regularly monitored with the aim of maintaining environmental quality, the fact that standard procedures rely heavily on open-water sampling may render them less than ideal for the early detection of pollution. In low-nutrient lakes, levels of biological production and community diversity are disproportionately high in shallow near-shore habitats, and it’s possible that… [Read more…]
March 27, 2012
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The ability of dam construction to disrupt water flows, sediment transport and aquatic populations is well known, and there is continuing interest in defining relationships between flow rates and the ecological integrity of stream systems. Given social pressures for water extraction and the difficulties of fully restoring pre-existing flows to dry river reaches downstream of… [Read more…]
March 27, 2012
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