Size-Mediated Effects of Water-Flow Velocity on Riverine Fish Species

作者：Del Signore A^*; Lenders H J R; Hendriks A J; Vonk J A; Mulder C; Leuven R S E W

来源：River Research and Applications, 2016, 32(3): 390-398.

DOI：10.1002/rra.2847

• allometry
• ecological risk assessment
• fish occurrence
• physical stress
• rivers

We applied species sensitivity distributions (SSDs), commonly used in chemical risk assessment, to quantify the impact of water-flow velocity on the presence of fish species in a river. SSDs for water-flow velocity were derived from observational field data (maximal velocity at which species occur, V-max) and laboratory measurements (critical swimming velocity, V-crit). By calculating the potentially affected fraction of the fish species of the river Rhine, effects of water-flow velocity on different life stages and guilds were estimated. V-max values for adults were significantly higher than those for juveniles and larvae. At water-flow velocity of 60cms(-1), half of the adults were affected, while half of the non-adult life stages were affected at velocities of 25 to 29cms(-1). There was a positive correlation between body size and fish tolerance to water-flow. As expected, rheophilic species tolerated higher water-flow velocities than eurytopic and limnophilic species. Maximal velocities measured in littoral zones of the Rhine were, on average, 10cms(-1), corresponding to an affected fraction of 2%. An increase in water-flow velocity up to 120cms(-1) as a result of passing vessels caused an increase in affected species to 75%. For a successful ecological river management, the SSD method can be used to quantify the trait-mediated effects of water-flow alterations on occurring species enabling to compare and rank the effects of chemical and physical stress.

• 出版日期2016-3