Materials, energy, and organisms from groundwater serve as resource subsidies to lotic systems. These subsidies influence food production and post-emergent fish growth and condition through nutrient inputs and water temperature changes. To test whether post-emergent fish grew faster in gaining sites, we grew hatchery post-emergent salmon in enclosures, sampled periphyton, benthic invertebrates, and wild salmon, and modeled fish growth across a gradient of groundwater – surface water exchange. Fish grew almost twice as fast in gaining (2.7%·day⁻¹) than in losing (1.5%·day⁻¹) sites. Fish from transient sites grew as much as gaining sites, but their condition was significantly lower (18.3% vs. 20.7%). Results suggest that groundwater – surface water exchange affects fish growth and energetic condition through direct and indirect pathways. Elevated nitrogen concentrations and consistently warmer water temperature in gaining sites have a strong effect on basal production with subsequent effects on invertebrate biomass, fish growth, and condition. Findings highlight the importance of groundwater – surface water exchange as a subsidy to rearing salmon and may inform strategies for restoring fish rearing habitat.

Cross-cultural differences exist in the typical temperature of water served with meals. North American people typically drink iced water/beverages while eating, whereas European or Asian people show a preference for room temperature water or hot water/tea, respectively. It has been reported that food perception and acceptance are influenced by oral temperature, as well as by serving temperature of food. Based on the fact that the iced or hot water served with meals can alter the oral temperature, the present study aimed to determine whether the temperature of served water can affect the sensory perception and acceptance of food subsequently consumed. Following a mouth rinse with water served at 4, 20, and 50°C for 5s, two different types of food, dark chocolate and cheddar cheese, were evaluated in terms of sensory intensity and overall liking. For the dark chocolate, the intensity ratings for sweetness, chocolate flavor, and creaminess were significantly lower when following water at 4°C than when following water at either 20 or 50°C. However, the modulatory effect of water temperature on sensory perception was not obtained with cheddar cheese. In addition, the temperature of served water altered the acceptance for the foods subsequently presented. Specifically, the overall liking for the dark chocolate was significantly lower when following water at 4°C than when following water at either 20 or 50°C. In conclusion, the present study demonstrates new empirical evidence that the consumption of iced water can decrease perceived intensities of sweetness, chocolate flavor, and creaminess for subsequently consumed chocolate. Our findings may provide one of plausible answers to the question of why North American people, who are more used to drinking iced water, show a strong preference for more highly sweetened foods.

A method for estimation of the upper temperature limit of water loss by food systems during preservation (drying, baking, extrusion, smoking, etc.) is proposed. These temperatures are related to the lower and higher critical solution temperatures, which were shown to depend on the chemical structure of system components. A determination method for the lower and higher critical solution temperatures in the plasticization curves obtained by calorimetry was developed.

To investigate biomarkers representing the physiological and biochemical responses of the brackish-water clam Corbicula japonica, we conducted a full factorial-design experiment to test different water-temperature levels (20 °C and 25 °C), salinity levels (5 and 20 psu), and food-availability levels (0.5 and 2.0 mg suspended solids (SS)·ind⁻¹·d⁻¹). Increase in water temperature significantly decreased superoxide dismutase (SOD) and catalase (CAT) activities and oxyradical-absorbance capacity (ORAC), leading to lipid peroxidation (i.e., oxidative damage). Salinity activated or inhibited these biochemical markers. Food availability supported a detoxification mechanism against oxidative stress. Principal-components and cluster analyses revealed that a total of eight experimental conditions fell into three groups related to water temperature and/or salinity. The shift from Group I (20 °C water temperature) to Group II (25 °C water temperature and 5-psu salinity) demonstrated that the condition index, SOD, CAT, and ORAC had significantly decreased. With the further shift to Group III (25 °C water temperature and 20-psu salinity), we found a prominent increase in ORAC, which led to oxidative damage but no mortality. We conclude that future habitat changes driven by global warming should be closely watched, particularly given that local anthropogenic disturbances further add to natural ones.

Much of our current knowledge about non-limiting dietary carbon supply for herbivorous zooplankton is based on experimental evidence and typically conducted at ~1 mg C L–¹ and ~20°C. Here we ask how low supply of dietary carbon affects somatic growth, reproduction, and survival of Daphnia magna and test effects of higher water temperature (+3°C relative to ambient) and brownification (3X higher than natural water color; both predicted effects of climate change) during fall cooling. We predicted that even at very low carbon supply (~5µg C L–¹), higher water temperature and brownification will allow D. magna to increase its fitness. Neonates (<24 h old) were incubated with lake seston for 4 weeks (October-November 2013) in experimental bottles submerged in outdoor mesocosms to explore effects of warmer and darker water. Higher temperature and brownification did not significantly affect food quality, as assessed by its fatty acid composition. Daphnia exposed to both increased temperature and brownification had highest somatic growth and were the only that reproduced, and higher temperature caused the highest Daphnia survival success. These results suggest that even under low temperature and thus lower physiological activity, low food quantity is more important than its quality for D. magna fitness.

Restoration of degraded freshwater ecosystems has gained considerable attention in the USA over the past decades. However, most projects focus almost entirely on the restoration of physical habitat or specific water quality parameters, while ignoring critical ecological processes related to food web re-establishment. In this study, we investigate the impact of riparian habitat in different stages of restoration on food availability for fish in four streams in Pennsylvania, USA. The riparian buffer habitats ranged from open meadow to mature forest and included new to long-term restoration sites. We quantified abundance and community composition of aquatic macroinvertebrates and riparian arthropods with aerial and ground-dwelling life history strategies. We found that riparian habitat and water temperature exert a strong influence over potential food resources for fish, with the open meadow habitat having highest abundance of terrestrial and aquatic insects, lowest taxa richness, and possible multivoltine aquatic insect life-history. Our results provide insight into the importance of riparian buffer habitat and water temperature on the composition of food availability for fish species of concern such as brook trout. The significant differences emphasize the need to include food web dynamics into riparian habitat restoration design to guide future rehabilitation projects focusing on fish conservation.

This corrects the article entitled “Daphnia magna fitness during low food supply under different water temperature and brownification scenarios” by the authors Andrea Gall, Martin J. Kainz and Serena Rasconi, published with DOI 10.4081/jlimnol.2016.1450. The data on somatic growth rates reported in the results section, paragraph “Life history traits”, page 165, were incorrect and the rectified data are presented. Fig. 4 has also been corrected accordingly.

We were examined the blood condition in the Sevenband grouper, Epinephelus septemfasciatus fed once a week during the high water temperature period in order to decreased to loss by viral nervous necrosis (VNN) at Nagasaki Prefectural Institute of Fisheries from June 2006 to March 2007. Survival rate of the fish fed 3 times per week were a little higher than the fish fed 5 times per week and the long period of the fish fed once a week during the high water temperature period. We considered that the blood condition of Triglyceride, Glutamic oxaloacetic transaminase, Alkaline phosphatase, Blood urea nitrogen, Glucose, Total bilirubin and Uric acid weren't influenced by the fish fed once a week during the high water temperature period. We considered that the blood condition of Hematocrit value, Hemoglobin, Red blood cells, Total cholesterol, Total protein, Alubumin, Amylase and Creatinine were influenced by the fish fed once a week during the high water temperature period. The fish fed once a week during 25degC up suggested to be hard limited food, because of the blood condition of Hematocrit value, Hemoglobin and Total cholesterol weren't recovered the fish fed 3 times per week level by finish of examination, and Red blood cells was recovered the fish fed 3 times per week level at seventeen weeks later.

Growth rates of individual freshwater shrimp of the species Atya lanipes and Xiphocaris elongata were measured in a second‐order stream in the Luquillo Experimental Forest in Puerto Rico over 10 years (1997–2007). Shrimp living at lower altitudes in warmer water and wider stream channels with more algal and detrital foods were predicted to grow and reproduce more rapidly. Shrimp were marked and recaptured periodically in pools located at three altitudes to determine whether temperature affected growth rates among individual A. lanipes and X. elongata. Mean annual water temperatures ranged from 20 to 24 °C with the uppermost pool being cooler than the lower pools. Mean annual growth rates for Atya and Xiphocaris were 0.27 and 0.1 mm carapace length, respectively, for all three populations. Differences in growth were partially influenced by how each species obtains its food. Atya is a filter feeder and scraper and has continuous access to suspended organic particles and biofilms. The slower growth rate for Xiphocaris elongata is most likely a result of the wider range in quality and accessibility of food resources. Differences in pool morphology and depths probably affected differences in food availability. Increased leaf litter retention in the deeper upper and lower pools probably increased shrimp growth rates, while washout of leaf litter from the relatively shallow, elongate mid‐altitude pool decreased Atya lanipes growth rates. These long‐lived, slow‐growing shrimp species transform a wide range of organic materials into their biomass. Because of the slow growth rates of these detritivores shrimp, tropical storms, hurricanes, droughts or other disturbances could have persistent, long‐term impacts on detrital processing and on the populations of their predators.