Interactive Effects Of Water Temperature Research Articles

Etlik Piliçlerde Sıcak İklimde Soğuk Su ve Yerleşim Sıklığının Oksidatif Metabolizmaya Etkisi

The present experiment was conducted to investigate the effect of drinking water temperature and stocking density (SD) on oxidative metabolism in the heart, liver, bursa fabricius, and thymus in broiler chickens raised under heat stress. The experiment comprised of 360 one-day-old Ross 308 male broiler chickens randomly divided to 6 experimental groups with 4 replicates in each group. Experimental treatments included three different SD (low = 12 birds/m2, medium = 15 birds/m2 or high = 18 birds/m2) and two different drinking water temperature (10oC or 31oC) in a 3 x 2 factorial arrangement. At the end of the experiment (42 days of age), two birds per replicate were euthanized for sample collection. The results indicated high SD increased oxidative damage and caused an increase in MDA formation in the heart, liver and thymus. On the other hand, cold water ameliorated the oxidative damage due to the high SD in the thymus. In the study, the statistically non-significant interaction was generally determined between cage stocking density and cold drinking water on the antioxidant system. Besides, while cold water administration increased CAT activity in heart and thymus tissues, decreased GSH activity. In conclusion, drinking water temperature and stocking density are key environmental factors effecting oxidative metabolism when broilers under high temperature conditions; however, more studies are needed in terms of the interactive effects of water temperature and stocking density on antioxidant enzymes under current conditions.

Climate and land-use changes interact to drive long-term reorganization of riverine fish communities globally

As climate change unfolds, changes in population dynamics and species distribution ranges are expected to fundamentally reshuffle communities worldwide. Yet, a comprehensive understanding of the mechanisms and extent of community reorganization remains elusive. This is particularly true in riverine systems, which are simultaneously exposed to changing temperature and streamflow, and where land-use change continues to be a major driver of biodiversity loss. Here, we use the most comprehensive compilation of fish abundance time series to date to provide a global synthesis of climate- and LU-induced effects on riverine biota with respect to changes in species thermal and streamflow affinities. We demonstrate that fish communities are increasingly dominated by thermophilic (warm-water) and limnophilic (slow-water) species. Despite being consistent with trends in water temperature and streamflow observed over recent decades, these community changes appear largely decoupled from each other and show wide spatial variation. We further reveal a synergy among climate- and land use-related drivers, such that community thermophilization is heightened in more human-modified systems. Importantly, communities in which species experience thermal and flow regimes that approach or exceed their tolerance thresholds (high community sensitivity), as well as species-poor communities (low community resilience), also display faster rates of compositional change. This research illustrates that quantifying vulnerability of riverine systems to climate change requires a broadening from a narrower thermal focus to more integrative approaches that account for the spatially varying and multifaceted sensitivity of riverine organisms to the interactive effects of water temperature, hydrology, and other anthropogenic changes.

Interactive effects of water temperature and stoichiometric food quality on Daphnia pulicaria

Abstract While water temperatures vary widely within and among lakes, most studies of food quality on lake zooplankton have been conducted across a relatively narrow temperature range. Given the strong links between food, temperature, and metabolism, there is a need to assess the interactive effects of water temperature and food quality on the life history and population growth rates of zooplankton. This study examined Daphnia pulicaria life history and population growth rates exposed to variable food P content (molar C:P ratios c. 100–900) across a range of temperatures (c. 12–30°C). Mass‐specific growth rate experiments were conducted for a period of 5 days, while Daphnia reproduction and survival metrics were measured for 28 days. Mass‐specific growth rates of D. pulicaria varied with food‐quality but the size of this effect depended on temperature. We observed a thermal limit of 28°C above which mortality reached 100%, while survival between 25 and 28°C was substantially reduced, after c. 20 days, in animals consuming food C:P ratios of 100. Poorer quality food (C:P 300–700) altered these temperature effects and increased the probability of survival in animals exposed to 25–28°C temperatures. When we examined the population‐level effects of these treatments, we found a rise in intrinsic rate with temperature with higher quality food, driven by an earlier age of first reproduction and shorter generation time. However, this increased population growth with temperature was not observed in animals consuming food with low P content. Altogether, we found strong interactive effects of temperature and food quality on Daphnia, with especially dynamic changes seen among differentially nourished animals raised in water above 25°C. These results demonstrate the complex non‐additive interactions of food quality and temperature responses in freshwater invertebrates and indicate that the effects of warming temperatures on zooplankton communities must be considered within the context of the animals’ nutrition and metabolism if monitoring and mitigation efforts are to be successful.

Predicting cyanobacterial biovolume from water temperature and conductivity using a Bayesian compound Poisson-Gamma model

Eutrophication and climate change scenarios engender the need to develop good predictive models for harmful cyanobacterial blooms (CyanoHABs). Nevertheless, modeling cyanobacterial biomass is a challenging task due to strongly skewed distributions that include many absences as well as extreme values (dense blooms). Most modeling approaches alter the natural distribution of the data by splitting them into zeros (absences) and positive values, assuming that different processes underlie these two components. Our objectives were (1) to develop a probabilistic model relating cyanobacterial biovolume to environmental variables in the Río de la Plata Estuary (35°S, 56°W, n = 205 observations) considering all biovolume values (zeros and positive biomass) as part of the same process; and (2) to use the model to predict cyanobacterial biovolume under different risk level scenarios using water temperature and conductivity as explanatory variables. We developed a compound Poisson-Gamma (CPG) regression model, an approach that has not previously been used for modeling phytoplankton biovolume, within a Bayesian hierarchical framework. Posterior predictive checks showed that the fitted model had a good overall fit to the observed cyanobacterial biovolume and to more specific features of the data, such as the proportion of samples crossing three threshold risk levels (0.2, 1 and 2 mm³ L−1) at different water temperatures and conductivities. The CPG model highlights the strong control of cyanobacterial biovolume by nonlinear and interactive effects of water temperature and conductivity. The highest probability of crossing the three biovolume levels occurred at 22.2 °C and at the lowest observed conductivity (∼0.1 mS cm−1). Cross-validation of the fitted model using out-of-sample observations (n = 72) showed the model’s potential to be used in situ, as it enabled prediction of cyanobacterial biomass based on two readily measured variables (temperature and conductivity), making it an interesting tool for early alert systems and management strategies. Furthermore, this novel application demonstrates the potential of the Bayesian CPG approach for predicting cyanobacterial dynamics in response to environmental change.

Warmer temperature and provision of natural substrate enable earlier metamorphosis in the critically endangered Baw Baw frog.

Temperature and food availability are known to independently trigger phenotypic change in ectotherms, but the interactive effects between these factors have rarely been considered. This study investigates the independent and interactive effects of water temperature and food availability on larval growth and development of the critically endangered Baw Baw frog, Philoria frosti. Larvae were reared at low (12°C) or high (17°C) water temperature in the absence or presence of substrate that controlled food availability, and body size and time to metamorphosis were quantified. Growth and development of larvae was influenced by the individual effects of temperature and food availability; time to metamorphosis was shorter in warm water treatment groups and in the presence of substrate and increased food. Unexpectedly, however, water temperature and food availability did not have an interactive effect on either time to metamorphose or body size at metamorphosis. Under all treatment groups, metamorphic onset occurred once a developmental size threshold was reached, indicating that growth rate and body size are key factors controlling the metamorphic process in Baw Baw frogs (consistent with the Wilbur-Collins model for ectotherm development). From an applied perspective, our findings have implications for amphibian conservation because they indicate that simple manipulations of temperature and food availability can be used to increase the rate of frog production in conservation breeding programs.

Daily growth of young-of-the-year largehead hairtail (Trichiurus japonicus) in relation to environmental variables in the East China Sea

Abstract Largehead hairtail (Trichiurus japonicus) is an important fish species in China Sea, characterized by wide distribution, extensive migration, long spawning period and high economic value. The East China Sea is one of the typical over-exploited ecosystems in the world where most of the fish populations are overfished. In spite of high fishing pressure over an extended period, the catch of largehead hairtail showed an increasing trend in recent years. In this study, using otolith microstructure analysis for daily ageing, we explored spawning seasonality of largehead hairtail and daily growth of young-of-the-year (YoY) largehead hairtail in the East China Sea. Spawning seasonality of largehead hairtail was found to be nearly year round with two dominant seasons: autumn and spring. The gradient forest method was used to identify the relative importance of various environmental variables in relation to daily growth of YoY largehead hairtail; the first six most important environmental variables were subsequently analyzed using generalized additive models for their specific associations with daily growth of YoY largehead hairtail. Results show that sea surface temperature (SST), sea bottom temperature (SBT), temperature difference (TD) between surface and bottom water, and mixed layer depth (MLD) are the most important variables for daily growth of almost all month cohorts. In addition, the consistent interactive effects of water temperature (SST and SBT) and MLD suggest that daily growth of YoY largehead hairtail is influenced by the interactive effects of water temperature and nutrient supplies. This study highlights the importance of understanding the reproductive process and early growth of largehead hairtail in relation to environmental variables, which has important implications for the sustainable management and utilization of largehead hairtail in the over-exploited China Seas.

Water temperature interacts with the insecticide imidacloprid to alter acute lethal and sublethal toxicity to mayfly larvae

ABSTRACTIncreased temperatures and exposure to agricultural insecticides are increasingly threatening freshwater ecosystems worldwide. However, their combined effects are still poorly understood. We investigated the individual and interactive effects of water temperature and imidacloprid, the most widely used neonicotinoid insecticide, on larvae of two New Zealand mayflies, Deleatidium spp. and Coloburiscus humeralis. Ninety-six-hour bioassays with imidacloprid were performed at 9, 12, 15, 18, 21 and 24°C, in a full-factorial design. Mayfly survivorship and sub-lethal responses of impairment and moulting were recorded. We documented synergistically increased mayfly mortality and immobility with exposure to imidacloprid at higher temperatures, implying temperature-enhanced toxicity of imidacloprid. Survivorship of both mayflies was synergistically reduced by the combination of imidacloprid exposure and increasing temperatures. The same interaction also affected mobility of C. humeralis and moulting frequency of Deleatidium. Our findings suggest that developing a more thorough understanding of temperature-contaminant interactions may be important to allow better protection of aquatic ecosystems.

Long-term effects of nutrient changes on rotifer communities in a subtropical lake

External nutrient loading has a major influence on the abundance, composition and diversity of zooplankton communities. To clarify how the reduction of nutrient loading during lake restoration interacts with other abiotic and biotic factors and how the interactive factors affect long-term changes in rotifer communities, we analyzed the relationships between the rotifer communities and environmental factors using a 17-year dataset. After the reduction of nutrients, both the abundance and biomass of rotifers declined, and the dominant rotifers changed from eutrophic-tolerant species to less tolerant ones. The lower TN:TP ratio that was caused by the imbalanced decrease in TN and TP after restoration promoted cyanobacteria, which negatively related to the resource-use efficiency of rotifers. Moreover, seasonal differences in the Shannon–Wiener index–TN relationships and the decrease in the Pielou index with the increase in water temperature implied there were interactive effects of water temperature and nutrients on species diversity. The study concluded that changes in rotifer abundance and community composition were mainly related to TN, but the changes in species diversity were mainly related to the interactive effects of the TN:TP ratio, water temperature and food quality. Our findings highlighted the effects caused by imbalanced nutrient changes on species diversity.

Corrigendum to “Interactive Effects of Water Temperature and Salinity on Growth and Mortality of Eastern Oysters, Crassostrea virginica: A Meta-Analysis Using 40 Years of Monitoring Data” [J. Shellfish Res. 2017;36(3):683–697

Corrigendum to “Interactive Effects of Water Temperature and Salinity on Growth and Mortality of Eastern Oysters, Crassostrea virginica: A Meta-Analysis Using 40 Years of Monitoring Data” [J. Shellfish Res. 2017;36(3):683–697

Interactive Effects of Water Temperature and Salinity on Growth and Mortality of Eastern Oysters,Crassostrea virginica: A Meta-Analysis Using 40 Years of Monitoring Data

Despite nearly a century of exploitation and scientific study, predicting growth and mortality rates of the eastern oyster (Crassostrea virginica) as a means to inform local harvest and management activities remains difficult. Ensuring that models reflect local population responses to varying salinity and temperature combinations requires locally appropriate models. Using long-term (1988 to 2015) monitoring data from Louisiana's public oyster reefs, we develop regionally specific models of temperature- and salinity-driven mortality (sack oysters only) and growth for spat ( 75 mm) oyster size classes. The results demonstrate that the optimal combination of temperature and salinity where Louisiana oysters experience reduced mortality and fast growth rates is skewed toward lower salinities and higher water temperatures than previous models have suggested. Outside of that optimal range, oysters are commonly exposed to combinations of temperature and salinity that are correlated with high mortality and reduced growth. How these combinations affect growth, and to a lesser degree mortality, appears to be size class dependent. Given current climate predictions for the region and ongoing large-scale restoration activities in coastal Louisiana, the growth and mortality models are a critical step toward ensuring sustainable oyster reefs for long-term harvest and continued delivery of the ecological services in a changing environment.

Effects of warming, nutrient enrichment and detritivore presence on litter breakdown and associated microbial decomposers in a simulated temperate woodland creek

Current scenarios of global environmental change predict rapid temperature increases, which can directly affect freshwater ecosystems. Leaf litter breakdown in aquatic environments constitutes a fundamental ecosystem process that is mediated by microbial decomposers and animal detritivores. In this study, we examined interactive effects of water temperature (two levels), nutrient concentration (two levels) and grazing pressure by Gammarus pulex (two levels) on breakdown rates of birch leaf litter, biomass and structure of the colonizing microbial community. Litter breakdown rates were stimulated by detritivores, with detritivore effects being enhanced by simultaneously increasing the temperature and adding the nutrients. The interaction between the three factors was synergistic and thus unpredictable from the effects of changes in individual factors. Bacterial community composition was affected by both detritivores and temperature, but less so by nutrient levels and fungal community composition changed upon detritivore activity but was independent of temperature and nutrients. These factors depended on each other in how they affected bacterial communities, but this did not prove true for fungal communities. Relative growth rates of G. pulex were not affected by temperature or nutrient level. We conclude that both abiotic and biotic factors that potentially affect ecosystem processes should be considered simultaneously in studies on effects of environmental change at the community and ecosystem level.

Climate change and pollution speed declines in zebrafish populations

Endocrine disrupting chemicals (EDCs) are potent environmental contaminants, and their effects on wildlife populations could be exacerbated by climate change, especially in species with environmental sex determination. Endangered species may be particularly at risk because inbreeding depression and stochastic fluctuations in male and female numbers are often observed in the small populations that typify these taxa. Here, we assessed the interactive effects of water temperature and EDC exposure on sexual development and population viability of inbred and outbred zebrafish (Danio rerio). Water temperatures adopted were 28 °C (current ambient mean spawning temperature) and 33 °C (projected for the year 2100). The EDC selected was clotrimazole (at 2 μg/L and 10 μg/L), a widely used antifungal chemical that inhibits a key steroidogenic enzyme [cytochrome P450(CYP19) aromatase] required for estrogen synthesis in vertebrates. Elevated water temperature and clotrimazole exposure independently induced male-skewed sex ratios, and the effects of clotrimazole were greater at the higher temperature. Male sex ratio skews also occurred for the lower clotrimazole exposure concentration at the higher water temperature in inbred fish but not in outbred fish. Population viability analysis showed that population growth rates declined sharply in response to male skews and declines for inbred populations occurred at lower male skews than for outbred populations. These results indicate that elevated temperature associated with climate change can amplify the effects of EDCs and these effects are likely to be most acute in small, inbred populations exhibiting environmental sex determination and/or differentiation.

Comparative Histological Changes in the Greenlip AbaloneHaliotis laevigataGastrointestinal Tract in Response to Water Temperature, Different Dietary Protein Levels, and Animal Age

The land-based culture of greenlip abalone Haliotis laevigata in southeastern Australia is carried out using seawater that is prone to seasonal temperature fluctuations and is done almost exclusively using artificial feeds. Although some nutrition research has been done to identify the optimum dietary protein level, typically farms use only 1 diet for grow-out after the juveniles are weaned. Little consideration has been given to the effects of fluctuating water temperatures and dietary protein levels on the morphology of the gastrointestinal tract (GIT) of abalone. Because these factors are known to impact growth in other aquatic species, it is important that they are investigated further to improve growth in abalone species. In this study, the histological changes of the GIT of greenlip abalone in response to 2 water temperatures and 4 dietary levels of crude protein (juvenile, 27% and 36%; subadult, 24% and 33%) for juveniles (1.75 g) and subadults (22.93 g) were investigated. The epithelial thickness of the stomach and crop; intestinal villus height, width, and area; lamina propria height; and stomach, crop, and intestinal neutral and acidic goblet cell numbers were measured. The stomach epithelium was significantly thicker at 14°C than 22°C in both juveniles and subadults, whereas the crop epithelium was significantly thicker at 22°C than 14°C in juveniles. The crop epithelial thickness of subadults was reduced by increasing dietary protein; however, juveniles did not show the same response. Juvenile abalone were more sensitive to temperature fluctuations than subadults, whereas significant effects of dietary protein levels were only observed in subadults. The alterations in the morphology of the GIT did not appear to be detrimental to the health and growth of the abalone. Further research is required to investigate the interactive effects of water temperature and dietary ingredients, particularly in regard to antinutritional factors, on the morphology and function of the GIT to improve our understanding of abalone physiology.

Temperature and dissolved oxygen influence growth and digestive enzyme activities of yellowtail kingfishSeriola lalandi(Valenciennes, 1833)

A 5 week experiment was carried out with juvenile yellowtail kingfish Seriola lalandi to investigate the interactive effects of water temperature (21, 24, or 27°C) and dissolved oxygen regime (normoxic vs. hypoxic) on the growth rate, feed intake and digestive enzyme activity of this species. Specific growth rate (SGR) was highest at 24°C, regardless of oxygen regime, but the SGRs of the fish exposed to hypoxia at 21, 24 and 27°C were 13%, 20% and 17% lower, respectively, than the SGRs recorded for the fish reared under normoxic conditions. The digestive enzyme activities (i.e. trypsin, lipase and a-amylase) were influenced by temperature but did not appear to be affected by dissolved oxygen concentration. Information about the effects of water temperature and dissolved oxygen on feeding, growth and digestive capacity of juvenile yellowtail kingfish could contribute to improving feed management decisions for production of this fish species under different environmental conditions.

Replacement of fish oil by poultry oil and canola oil in yellowtail kingfish (Seriola lalandi) at optimal and suboptimal temperatures

Fish oil has been replaced by alternative oils to reduce the cost of aquaculture diets, but fish growth may be compromised when fish are fed these oils at suboptimal temperatures. A 5-week feeding trial was conducted to examine the interactive effects of water temperature and the partial or total replacement of fish oil with poultry oil and canola oil on the performance of yellowtail kingfish (YTK, Seriola lalandi), in the early stages of the production cycle. Practical diets were identical in composition, except the dietary lipid component was supplemented with 100% lipid as either poultry oil (PO), canola oil (CO), a blend of fish oil and poultry oil (FO/PO; 50:50) or a blend of fish oil and canola oil (FO/CO; 50:50). A control diet was included and the dietary lipid component contained 100% fish oil (FO). Fish fed the CO diet at 18°C had inferior growth performance, feed efficiency and nutrient retention, and showed higher incidences of green liver and lower plasma cholesterol levels than those fed the other diets. Whole body proximate composition was influenced by water temperature, but not diet, except moisture content which was highest in fish fed CO. The fatty acid composition of fillet lipid correlated with the PO and CO inclusion, in that the proportions of 18:1n-9, 18:2n-6 and 18:3n-6 all increased with increasing dietary PO and CO. The concentrations of 20:5n-3, 22:6n-3 and 20:4n-6 in the fillet lipid were reduced with increasing contents of dietary PO and CO. Our results confirmed that 100% poultry oil and 50% canola oil can replace fish oil in diets without reducing growth, but 100% canola oil results in poor fish growth compared with the FO control, regardless of water temperature. These findings are useful in dietary formulation to reduce feed costs without compromising yellowtail kingfish growth.

Costs of living for juvenile Chinook salmon (Oncorhynchus tshawytscha) in an increasingly warming and invaded world

Rapid environmental change in freshwater ecosystems has created a need to understand the interactive effects of multiple stressors, with temperature and invasive predators identified as key threats to imperiled fish species. We tested the separate and interactive effects of water temperature and predation by non-native smallmouth bass ( Micropterus dolomieu ) on the lethal (mortality) and sublethal (behavior, physiology, and growth) effects for juvenile Chinook salmon ( Oncorhynchus tshawytscha ) in seminatural stream channel experiments. Over 48 h trials, there was no difference in direct predation with warmer temperatures, but significant interactive effects on sublethal responses of juvenile salmon. Warmer temperatures resulted in significantly stronger and more variable antipredator responses (surface shoaling and swimming activity), while physiological indicators (plasma glucose, plasma cortisol) suggested suppression of physiological mechanisms in response to the combined stressors. These patterns corresponded with additive negative growth in predation, temperature, and combined treatments. Our results suggest that chronic increases in temperature may not increase direct predation over short periods, but can result in significant sublethal costs with negative implications for long-term development, disease resistance, and subsequent size-selective mortality of Pacific salmon.