Water temperature (Tw) is a key determinant of freshwater ecosystem status and cause for concern under a changing climate. Hence, there is growing interest in the feasibility of moderating rising Tw through management of riparian shade. The Loughborough University Temperature Network (LUTEN) is an array of 36 water and air temperature (Ta) monitoring sites in the English Peak District set‐up to explore the predictability of local Tw, given Ta, river reach, and catchment properties. Year 1 of monitoring shows that 84%–94% of variance in daily Tw is explained by Ta. However, site‐specific logistic regression parameters exhibit marked variation and dependency on upstream riparian shade. Perennial spring flows in the lower River Dove also affect regression model parameters and strongly buffer daily and seasonal mean Tw. The asymptote of the models (i.e. maximum expected Tw) is particularly sensitive to groundwater inputs. We conclude that reaches with spring flows potentially offer important thermal refuges for aquatic organisms against expected long‐term warming of rivers and should be afforded special protection. Copyright © 2013 John Wiley & Sons, Ltd.

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Foraging by benthivorous fish can affect bed material mobility and sediment flux. This paper collates evidence of benthic feeding effects at local scales and evaluates the possibility that large numbers of foraging fish, each of which accomplishes a small amount of geomorphic work when feeding, may have a cumulative effect across river systems. A first synthesis of research from several disciplines provides a deeper understanding of how fish disturb and condition bed materials with implications for sediment mobility. To evaluate the spatial extent of benthic feeding and therefore the potential for it to have a large‐scale effect, the distribution of benthivorous fish is established across a large river network. After quality control, the dataset yields a comprehensive set of fish community information based on over 61 000 individuals and 30 species at 176 sites. The factors that are likely to mediate foraging and its geomorphological effectiveness are considered. A novel scoring system that incorporates three key controls (fish feeding behaviour, fish abundance and fish body size) is then applied across the river network to predict where geomorphologically effective benthic feeding is feasible and its possible relative magnitude. Our results demonstrate, for the first time, that the potential for zoogeomorphic impacts is widespread but variable in space as a function of community composition and the abundance of key benthivores. An initial calibration against measured field impacts suggests that benthic feeding may cause measurable geomorphological disturbance at more than 90% of sites in this large network. Together, previous work and this unique analysis suggest that benthic feeding is sufficiently effective and extensive to warrant additional research. Investigating the role of benthivorous fish in fluvial geomorphology is important because it may yield results that challenge the assumption that biota are irrelevant sources of energy in geomorphological systems. Key research questions and a roadmap to facilitate progress are identified. © 2018 John Wiley & Sons, Ltd.

Nocturnal water temperature (Tw) affects the behaviour of aquatic biota and metabolism of whole rivers. However, night-time water temperature (nTw) is poorly understood because spot samples are typically taken during daylight hours, or Tw series are aggregated in ways that mask sub-daily properties. This paper examines 15-minute measurements of Tw and air temperature (Ta) collected at 36 sites in the Rivers Dove and Manifold, English Peak District.Data were stratified by day and night then analysed using hysteresis, auto-correlation and logistic regression techniques. Daily hysteresis loops show lagged responses between nTw and previous daylight air temperatures (dTa), plus the influence of groundwater and discharge variations. Logistic regression models were modified using a seasonal factor and explained between 80 to 94% of the variance in daily maximum nTw; minimum nTw were predicted with less skill, particularly for headwater sites in summer. Downstream variations in model parameters also reflect the influence of groundwater and/or riparian shade, and prevailing weather conditions. A case is presented where an intense summer storm resulted in the propagation of a thermal wave that produced maximum Tw at some sites during hours of darkness. Hence, our findings show that Tw management by riparian shade has to be seen in a catchment wide context, with anticipated benefits normalised for weather variability, extreme rainfall events, local influence of groundwater, and channel structures.Keywords: Water temperature; logistic regression; hysteresis curve; thermal wave; riparian shade; river management. 3 INTRODUCTIONAmbient water temperature (Tw) regulates the photosynthesis of aquatic plants and the metabolism of cold-blooded piokilotherms, including fish, amphibians and aquatic invertebrates (Berry & Björkman 1980; Farrell 2009). Extreme Tw can stress or ultimately prove lethal to biota (e.g. Dallas & Rivers-Moore 2012;Martins et al. 2011) although some fauna can deploy avoidance strategies and/or acclimate to high temperatures (Breau et al. 2011;Cox & Rutherford, 2000; Geist et al. 2011). Nonetheless, sub-lethal Tw can still impact on spawning and breeding, hatching, growth, behaviour, distribution and phenology, thereby altering population structure and dynamics (Durance and Ormerod, 2007; Thackeray et al. 2010;Ward & Stanford 1982). There is evidence that Tw is rising in response to climate and environmental drivers, such as land-use change, land-drainage and modification of riparian vegetation (Broadmeadow et al. 2011;Langan et al., 2001;Malcolm et al., 2008;Webb, 1996). Consequently, there have been calls to manage rivers in ways that mitigate temperature increases to 'buy time' for ecosystems to adapt (Hansen et al., 2003;Wilby et al., 2010) whilst achieving other co-benefits (see for example: Nõges et al., 2010).To date, nocturnal water temperatures (nTw) have received relatively little if any explicit attention (see for example the review of Webb et al. [2008]). This is because spot Tw measurem...