Evaporative Water Loss Research Articles

Supratidal existence drives phenotypic divergence, but not speciation, in tropical rocky-shore snails

AbstractThe mechanisms underlying the evolutionary adaptation of animals that transcend the ecological barrier separating the intertidal and supratidal zones of rocky shores are poorly understood. Different wetting frequencies in these zones in tropical regions (daily vs. seasonally, respectively) impose different physical stressors, which should drive phenotypic variation and ultimately speciation in the animals that inhabit them. We studied morphological, physiological and genetic variation in a tropical high-shore gastropod that transcends these zones [Echinolittorina malaccana (Philippi, 1847)]. Variation in melanization, shell features and evaporative water loss was linked to regular seawater wetting, frequent activity and feeding, and solar exposure in intertidal snails, and to inactivity and prolonged aestivation in the shade during continuous air exposure in supratidal snails. Despite selective pressure for phenotypic divergence, and reproductive isolation of the populations in either zone, their mitochondrial COI gene sequences confirmed that they represent a single species. Speciation in our study case is probably constrained by the limitation on activity, mating and reproduction of supratidal snails, such that their populations can only be sustained through intertidal pelagic larval recruitment. Comparisons with other studies suggest that supratidal speciation and specialization for life in this zone probably require moderation of the abiotic (desiccative) conditions, to facilitate greater activity and interaction of animals during air exposure.

Age-Related Changes in the Thermoregulatory Properties in Bank Voles From a Selection Experiment.

As with many physiological performance traits, the capacity of endotherms to thermoregulate declines with age. Aging compromises both the capacity to conserve or dissipate heat and the thermogenesis, which is fueled by aerobic metabolism. The rate of metabolism, however, not only determines thermogenic capacity but can also affect the process of aging. Therefore, we hypothesized that selection for an increased aerobic exercise metabolism, which has presumably been a crucial factor in the evolution of endothermic physiology in the mammalian and avian lineages, affects not only the thermoregulatory traits but also the age-related changes of these traits. Here, we test this hypothesis on bank voles (Myodes glareolus) from an experimental evolution model system: four lines selected for high swim-induced aerobic metabolism (A lines), which have also increased the basal, average daily, and maximum cold-induced metabolic rates, and four unselected control (C) lines. We measured the resting metabolic rate (RMR), evaporative water loss (EWL), and body temperature in 72 young adult (4 months) and 65 old (22 months) voles at seven ambient temperatures (13–32°C). The RMR was 6% higher in the A than in the C lines, but, regardless of the selection group or temperature, it did not change with age. However, EWL was 12% higher in the old voles. An increased EWL/RMR ratio implies either a compromised efficiency of oxygen extraction in the lungs or increased skin permeability. This effect was more profound in the A lines, which may indicate their increased vulnerability to aging. Body temperature did not differ between the selection and age groups below 32°C, but at 32°C it was markedly higher in the old A-line voles than in those from other groups. As expected, the thermogenic capacity, measured as the maximum cold-induced oxygen consumption, was decreased by about 13% in the old voles from both selection groups, but the performance of old A-line voles was the same as that of the young C-line ones. Thus, the selection for high aerobic exercise metabolism attenuated the adverse effects of aging on cold tolerance, but this advantage has been traded off by a compromised coping with hot conditions by aged voles.

Vocal panting: a novel thermoregulatory mechanism for enhancing heat tolerance in a desert-adapted bird

Animals thriving in hot deserts rely on extraordinary adaptations and thermoregulatory capacities to cope with heat. Uncovering such adaptations, and how they may be favoured by selection, is essential for predicting climate change impacts. Recently, the arid-adapted zebra finch was discovered to program their offspring’s development for heat, by producing ‘heat-calls’ during incubation in hot conditions. Intriguingly, heat-calls always occur during panting; and, strikingly, avian evaporative cooling mechanisms typically involve vibrating an element of the respiratory tract, which could conceivably produce sound. Therefore, we tested whether heat-call emission results from a particular thermoregulatory mechanism increasing the parent’s heat tolerance. We repeatedly measured resting metabolic rate, evaporative water loss (EWL) and heat tolerance in adult wild-derived captive zebra finches (n = 44) at increasing air temperatures up to 44 °C. We found high within-individual repeatability in thermoregulatory patterns, with heat-calling triggered at an individual-specific stage of panting. As expected for thermoregulatory mechanisms, both silent panting and heat-calling significantly increased EWL. However, only heat-calling resulted in greater heat tolerance, demonstrating that “vocal panting” brings a thermoregulatory benefit to the emitter. Our findings therefore not only improve our understanding of the evolution of passerine thermal adaptations, but also highlight a novel evolutionary precursor for acoustic signals.

Relationships between the material properties of silicone hydrogels: Desiccation, wettability and lubricity.

Silicone hydrogels (SiHy), represent composite matrices composed of hydrophobic gas permeable silicone (Si) rich core and a surface enriched with hydrophilic polymer moieties. Their utilization in contact lens design requires number of SiHy properties (hydration, wettability, lubricity) to be optimized for the challenging conditions at the ocular surface. Typical limitations in literature are that (i) these properties are studied in isolation, monitoring only one parameter but not the rest of them, and (ii) measurements are performed with hydrated samples immediately after removal from storage solutions. Here we study the simultaneous evolution of critical material properties (evaporative loss of water, water contact angle, coefficient of friction) of different SiHy subjected to continuous blink-like desiccation/rehydration cycling. SiHy with wetting agents incorporated in their core (narafilcon A, senofilcon A) were particularly susceptible to extended desiccation. Stenfilcon A, a material with only 3% bulk Si content maintained its performance for 4 h of cycling, and delefilcon A (80% surface water content) resisted extended 8 h of desiccation/rehydration runs. Strong correlation exists between the evolution of SiHy wettability and lubricity at ≥4 h of blink-like cycling. Understanding the interplay between SiHy properties bears insights for knowledge based design of novel ophthalmic materials.

Integrating environmental understanding into freshwater floatovoltaic deployment using an effects hierarchy and decision trees

In an era of looming land scarcity and environmental degradation, the development of low carbon energy systems without adverse impacts on land and land-based resources is a global challenge. ‘Floatovoltaic’ energy systems—comprising floating photovoltaic (PV) panels over water—are an appealing source of low carbon energy as they spare land for other uses and attain greater electricity outputs compared to land-based systems. However, to date little is understood of the impacts of floatovoltaics on the hosting water body. Anticipating changes to water body processes, properties and services owing to floatovoltaic deployment represents a critical knowledge gap that may result in poor societal choices and water body governance. Here, we developed a theoretically-derived hierarchical effects framework for the assessment of floatovoltaic impacts on freshwater water bodies, emphasising ecological interactions. We describe how the presence of floatovoltaic systems may dramatically alter the air-water interface, with subsequent implications for surface meteorology, air-water fluxes and physical, chemical and biological properties of the recipient water body. We apply knowledge from this framework to delineate three response typologies—‘magnitude’, those for which the direction and magnitude of effect can be predicted; ‘direction’, those for which only the direction of effect can be predicted; and ‘uncertain’, those for which the response cannot be predicted—characterised by the relative importance of levels in the effects hierarchy. Illustrative decision trees are developed for an example water body response within each typology, specifically, evaporative water loss, cyanobacterial biomass, and phosphorus release from bed sediments, and implications for ecosystem services, including climate regulation, are discussed. Finally, the potential to use the new understanding of likely ecosystem perturbations to direct floatovoltaic design innovations and identify future research priorities is outlined, showcasing how inter-sectoral collaboration and environmental science can inform and optimise this low carbon, land-sparing renewable energy for ecosystem gains.

Plant-wide assessment of high-pressure membrane contactors in natural gas sweetening – Part I: Model development

This paper presents a predictive mathematical model of high-pressure membrane contactor, with a view to developing a plant-wide model of natural gas sweetening including amine regeneration. We build upon an existing model of high-pressure membrane contactor by Quek et al. [Chem Eng Res Des132:1005–1019, 2018], which uses a combination of 1-d and 2-d mass-balance equations to predict the CO2 absorption flux and membrane wetting under lean solvent operation. For the first time, quantitative predictions of the CO2 absorption flux can be made under both lean and semi-lean operations. A 1-d energy balance that accounts for the solvent evaporative losses and the exothermic CO2 absorption into the amine is solved alongside the mass-balance equations, in order to predict the solvent temperature profile inside the contactor. The evaporative losses of water and amines can be quantified separately, as well as the absorptive losses of light hydrocarbons with the amine solvent. The model’s predictive capability is tested against data from a lab-scale module and a pilot-scale module that is operated under industrially relevant conditions at a natural gas processing facility in Malaysia. A close agreement between model predictions and measurements of the CO2 absorption flux, solvent temperature profile, and hydrocarbon loss is observed for a wide range of gas and solvent flowrates and compositions, thereby validating the modeling assumptions. The contactor model is combined in a plant-wide model of natural gas sweetening in the companion paper, where it is used for process integration and analysis.

Evaporation loss along the Calueque-Oshakati Canal in the Cuvelai-Etosha Basin (Northern Namibia): evidence from stable isotopes and hydrochemistry

ABSTRACT Since 1973, Kunene River water has been carried from the Calueque reservoir in Angola along a 160 km open concrete canal to the town of Oshakati in the central part of the Cuvelai-Etosha Basin and has been supplying drinking water to the most densely populated rural area of Namibia. Despite its importance for the region, intra-seasonal water quality and the technical condition of the canal are not routinely checked. Water samples were collected during four field campaigns right before the onset of the rainy season (November 2013 and 2014), and after the rainy season (June 2014 and May 2015), at 16 sites along the canal for stable water isotopes (deuterium, oxygen-17 and oxygen-18) and hydrochemical analyses. The isotope patterns and chemical composition of the canal water is discussed in comparison to local rain, Kunene source water, surface water and groundwater. Clear isotope enrichment indicates evaporative loss of water. A Craig–Gordon model was used to estimate water loss. The loss increases with distance from the source with a maximum of up to 10 %, depending on the season. The results are discussed in context of water availability, vulnerability and water resources management in this water-scarce area.

The influence of spatially heterogeneous anthropogenic change on bill size evolution in a coastal songbird.

Natural history collections provide an unparalleled resource for documenting population responses to past anthropogenic change. However, in many cases, traits measured on specimens may vary temporally in response to a number of different anthropogenic pressures or demographic processes. While teasing apart these different drivers is challenging, approaches that integrate analyses of spatial and temporal series of specimens can provide a robust framework for examining whether traits exhibit common responses to ecological variation in space and time. We applied this approach to analyze bill morphology variation in California Savannah Sparrows (Passerculus sandwichensis). We found that bill surface area increased in birds from higher salinity tidal marshes that are hotter and drier. Only the coastal subspecies, alaudinus, exhibited a significant increase in bill size through time. As with patterns of spatial variation, alaudinus populations occupying higher salinity tidal marshes that have become warmer and drier over the past century exhibited the greatest increases in bill surface area. We also found a significant negative correlation between bill surface area and total evaporative water loss (TEWL) and estimated that observed increases in bill size could result in a reduction of up to 16.2% in daily water losses. Together, these patterns of spatial and temporal variation in bill size were consistent with the hypothesis that larger bills are favored in freshwater‐limited environments as a mechanism of dissipating heat, reducing reliance on evaporative cooling, and increasing water conservation. With museum collections increasingly being leveraged to understand past responses to global change, this work highlights the importance of considering the influence of many different axes of anthropogenic change and of integrating spatial and temporal analyses to better understand the influence of specific human impacts on population change over time.

Investigation of covers and chemical treatment for the suppression of cyanobacteria in water treatment systems

AbstractAlgal growth in water treatment plants can lead to the introduction of toxin and odour compounds from cyanobacteria and causes filter fouling. Here, we investigate the use of woven polypropylene covers and a proprietary copper sulfate formulation (EarthTec) to prevent algal growth within mesocosms designed to simulate settling basins. Chlorophyll a, soluble nutrients, weather patterns and cyanobacterial gene abundance were measured. The covers suppressed algal and cyanobacterial growth in mesocosms, likely due to a combination of light blockage and prevention of insects from entering the mesocosms. In contrast, mesocosms amended with EarthTec exhibited little difference from the control mesocosms in terms of algal growth. qPCR analysis revealed that only a small fraction of cyanobacteria in the system contained genes necessary for the production of the microcystin toxin. Despite differences between mesocosms and full‐scale settling basins, the data here suggest that woven covers can suppress algal growth while minimising evaporative water losses.

Identification and Determination of Epidermal Fatty Acids Extracted in Walterinnesia morgani (Elapidae) Using GC/FID

Walterinnesia morgani is one of the venomous snakes that localized in Khuzestan Province in southwestern of Iran, The epidermis of snakes is made of six epidermal layers termed oberhautchen, β, mesos α, lacunar, and clear, and have been shown to function as the main barrier to evaporative water loss and essential for life on dry land. Regarding the temperature of Khuzestan province and its high temperature, identification of fatty acids in W. morgani skin can help us to identify the adaptability of this species to temperature conditions. The present study skin lipids were analyzed by GC/FID and fatty acids identified in skin include: Octadecanoic acid, Linoleic acid, Tricosanoic acid, Cis-9-Oleic acid, Nervonic acid, Heptadecanoic acid, Palmitic acid and Cis-11-eicosenoic acid. The presence of these fatty acids in the W. morgani skin is effective in survival and tolerance in tropical weather conditions in Khuzestan province.

Stable nitrogen and oxygen isotope fractionation during precipitation of nitrate salt from saturated solutions.

Nitrate is an oxyanion similar to CO3 - and thus should undergo stable N and O isotope fractionation during dissolution or precipitation. This process should dominate abiotic soil nitrate processes in hyperarid regions of Earth and possibly Mars. The N and O isotope fractionations during the precipitation of nitrate salt from saturated solutions at ~20°C were determined by two methods: rapid precipitation by antisolvent crystallization and slow uninhibited precipitation in a desiccator. In the antisolvent crystallization procedure, increasing volumes of acetone were added to samples of saturated sodium and strontium nitrate solutions to instantaneously precipitate nitrate salt. In the slow procedure (requiring weeks), slow evaporative water loss drove the process. There was little difference between the two procedures. Using a Rayleigh model, the calculated N fractionation (15 εproduct-residual ) ranged from 1.69‰ to 2.77‰, whereas for O, the 18 εproduct-residual values were between 1.27‰ and 4.61‰. The N isotope fractionation between NO3 - and the metal solid is similar to that between C in dissolved CO3 -2 and carbonates. We found that O versus N isotope plots of soil nitrate in a cold/dry Antarctic chronosequence had slopes similar to those from the experiments, revealing abiotic transport. In the Atacama Desert, where the soil nitrates are a mix of biological and tropospheric nitrate, there is an inverse relationship between soil N and O isotopes. These two relationships were compared with the isotope composition of nitrate from Martian meteorite EETA79001. While the N and O isotope composition of the Martian nitrate is remarkably similar to that of the present Atacama Desert, the interpretation of the slope of the O versus N isotopes remains ambiguous due to the limited number of samples. Additional NO3 samples from Martian meteorites are needed to address the question of abiotic versus biotic alteration of NO3 - on Mars.

Thin-skinned invaders: geographic variation in the structure of the skin among populations of cane toads (Rhinella marina)

AbstractThe structure of the skin may evolve rapidly during a biological invasion, for two reasons. First, novel abiotic challenges such as hydric conditions may modify selection of traits (such as skin thickness) that determine rates of evaporative water loss. Second, invaders might benefit from enhanced rates of dispersal, with locomotion possibly facilitated by thinner (and hence more flexible) skin. We quantified thickness of layers of the skin in cane toads (Rhinella marina) from the native range (Brazil), a stepping-stone population (Hawaii), and the invaded range in Australia. Overall, the skin is thinner in cane toads in Australia than in the native range, consistent with selection on mobility. However, layers that regulate water exchange (epidermal stratum corneum and dermal ground substance layer) are thicker in Australia, retarding water loss in hot dry conditions. Within Australia, epidermal thickness increased as the toads colonized more arid regions, but then decreased in the arid Kimberley region. That curvilinearity might reflect spatial sorting, whereby mobile (thin-skinned) individuals dominate the invasion front; or the toads’ restriction to moist sites in this arid landscape may reduce the importance of water-conservation. Further work is needed to clarify the roles of adaptation versus phenotypic plasticity in generating the strong geographic variation in skin structure among populations of cane toads.

Water Costs of Gas Exchange by a Speckled Cockroach and a Darkling Beetle.

Respiratory water loss during metabolic gas exchange is an unavoidable cost of living for terrestrial insects. It has been suggested to depend on several factors, such as the mode of gas exchange (convective vs. diffusive), species habitat (aridity), body size and measurement conditions (temperature). We measured this cost in terms of respiratory water loss relative to metabolic rate (respiratory water cost of gas exchange; RWL/V˙CO2) for adults of two insect species, the speckled cockroach (Nauphoeta cinerea) and the darkling beetle (Zophobas morio), which are similar in their mode of gas exchange (dominantly convective), habitat (mesic), body size and measurement conditions, by measuring gas exchange patterns using flow-through respirometry. The speckled cockroaches showed both continuous and discontinuous gas exchange patterns, which had significantly a different metabolic rate and respiratory water loss but the same respiratory water cost of gas exchange. The darkling beetles showed continuous gas exchange pattern only, and their metabolic rate, respiratory water loss and respiratory cost of gas exchange were equivalent to those cockroaches using continuous gas exchange. This outcome from our study highlights that the respiratory water cost of gas exchange is similar between species, regardless of gas exchange pattern used, when the confounding factors affecting this cost are controlled. However, the total evaporative water cost of gas exchange is much higher than the respiratory cost because cuticular water loss contributes considerably more to the overall evaporative water loss than respiratory water. We suggest that the total water cost of gas exchange is likely to be a more useful index of environmental adaptation (e.g., aridity) than just the respiratory water cost.

Comparative evaluation of continuous piggery wastewater treatment in open and closed purple phototrophic bacteria-based photobioreactors

Purple phototrophic bacteria (PPB) represent an innovative approach for wastewater treatment with a high metabolic plasticity, able to grow under aerobic and anaerobic conditions. This study comparatively assessed the long-term performance (450 days of operation) of an open and closed PPB-based photobioreactor treating of piggery wastewater (PWW). The influence of wastewater dilution, illuminated area to volume ratio, biomass settling and recirculation, and infrared light intensity on wastewater treatment was evaluated at 7 days of hydraulic retention time. An increase in PWW dilution from 4 to 8 folds did not entail higher TOC removal efficiencies (REs) in the open photobioreactor (87% versus 89%), but a significant increase in the closed photobioreactor (from 73% to 80%). The increase in the illuminated area to volume ratio increased TN-REs up to 99% and 49% in the open and closed photobioreactor, respectively, with a concomitant increase in the temperature of both systems. However, temperature control did not mediate a significant enhancement in PWW treatment. Biomass settling and recirculation resulted in higher TN-REs (80%) and TOC-REs (90%) in the closed photobioreactor. The increase in infrared radiation from 100 to 300 W m-2 fostered PPB growth. High water evaporation losses (deteriorating effluent quality) were recorded in the open photobioreactor, where carbon dioxide and ammonia stripping were identified as the main pathways supporting carbon and nitrogen removal.

Precipitation, runoff, and yields from terraced drylands with stubble‐mulch or no tillage1

AbstractDryland crops rely on precipitation as their exclusive water source, but storm water runoff decreases the amount available for biomass and grain production. Management practices that minimize runoff often increase the opportunity time for infiltration and improve precipitation storage as soil water. Our objective was to quantify storm water runoff from contour farmed terraces in relation to precipitation and field characteristics and then relate runoff to soil water at planting and yields of wheat (Triticum aestivum L.) and sorghum [Sorghum bicolor (L.) Moench] grown in a 3‐yr wheat–sorghum–fallow (WSF) rotation. Comparisons of long‐term (1984–2010) runoff observations indicated mean annual runoff for both uncropped periods of the WSF rotation were significantly greater with no‐tillage (NT) than stubble‐mulch (SM) tillage. By contrast, soil loss was greater for SM than NT because residue cover of undisturbed NT soil was less subject to entrainment and loss. Increasing field slope from 1.2 to 1.8% produced greater fallow runoff, which is water lost from dryland production. Nevertheless, soil water was significantly greater with NT, which reduced evaporative losses during fallow compared with SM. Long‐term wheat yields exhibited no difference due to tillage, but NT grain sorghum yields increased significantly over SM tillage. The data show that while runoff with NT was typically greater than SM, profile soil water at planting was also greater for NT and increased grain sorghum yields significantly. We conclude that decreasing evaporative water losses with NT residues is the primary factor affecting soil water conservation.

4E Analysis and Design of a Combined Cycle with a Geothermal Condensing System in Iranian Moghan Diesel Power Plant

Considering the new issues human society faces now, environmental issues, and climate change is one of the primary and most essential phenomena which have been caused by the unsustainable lifestyle of men over the last two centuries. Power and energy are some of the leading role players of today’s human lifestyle and one of the most effective in which the environment is affected. This article represents the results of research over the possibility of recovering waste heat and determination of design parameters of a waste heat steam generator for medium speed set of diesel generators, with the rated 42[Formula: see text]MW capacity and are used for power generation. The main goals of this study are to manage the waste heat of the engines and to help the severe water leakage of the power plant. In this paper, for managing the waste heat, a combined steam cycle is being designed for this process. This system added 19[Formula: see text]MW the overall electricity generation, and the exergy and energy efficiencies of the system are being increased by 29.2% and 32.8%. Moreover, finally, a geothermal condensing system (GCS) is designed to control the water shortages of the steam power unit condensing system. The GCS condensing system developed in this paper helps to reduce the water evaporation losses in the cooling water by more than 79% compared to the wet cooling towers.

Stable isotope geochemistry of pedogenic carbonates in calcareous materials, Iran: a review and synthesis

Abstract The stable isotopic composition of pedogenic carbonate forms in equilibrium with environmental parameters and, thus, records palaeoenvironmental signals. The aims of this study are to synthesize available data on the stable isotopic composition of Quaternary pedogenic carbonates in calcareous parent materials of Iran and to decipher paleoenvironmental implications of the isotopic data for the country. Isotopic composition and microfabric of pedogenic carbonates in 18 pedons in both gravelly (calcareous alluvium in central Iran) and non-gravelly deposits (calcareous loess in northeastern Iran) have been investigated. The results indicate that in limestone-derived soils of central Iran in situ weathering of calcareous pebbles is a major source of Ca for genesis of the carbonates, and carbonate features consist of micritic calcite crystals. In the loessic soils of northeastern Iran, pedogenic carbonates show a dominance of nodule morphology and are classified as orthic nodules. Microfabric analysis reveals that most of the carbonates have not been altered by diagenetic processes, especially the Holocene carbonates, and are suitable for isotopic study and palaeoreconstructions. In limestone-derived soils within the arid region of central Iran, the δ 18 O and the δ 13 C values of carbonates indicate their enrichment due to the effects of evaporative water loss, a decline in plant density and the entrance of atmospheric CO 2 into the soils. In semi-arid ecosystems of central and northeastern Iran, most of the Holocene carbonates have formed in equilibrium with the ambient environment and are suitable for palaeoenvironmental reconstructions. The combination of carbon and oxygen isotopic data demonstrates the dominant role of climate in determining the δ 13 C values of carbonates. There is a strong relationship between the δ 13 C values of carbonates and rainfall, and between O isotopes and aridity indices. Stable isotope patterns in Holocene soils appear to provide data for models that can then be used to interpret the many localities where Pleistocene-aged soils and associated carbonate exist.

Implementing Sustainable Irrigation in Water-Scarce Regions under the Impact of Climate Change

The sustainability of irrigated agriculture is threatening due to adverse climate change, given future projections that every one in four people on Earth might be suffering from extreme water scarcity by the year 2025. Pressurized irrigation systems and appropriate irrigation schedules can increase water productivity (i.e., product yield per unit volume of water consumed by the crop) and reduce the evaporative or system loss of water as opposed to traditional surface irrigation methods. However, in water-scarce countries, irrigation management frequently becomes a complex task. Deficit irrigation and the use of non-conventional water resources (e.g., wastewater, brackish groundwater) has been adopted in many cases as part of a climate change mitigation measures to tackle the water poverty issue. Protected cultivation systems such as greenhouses or screenhouses equipped with artificial intelligence systems present another sustainable option for improving water productivity and may help to alleviate water scarcity in these countries. This article presents a comprehensive review of the literature, which deals with sustainable irrigation for open-field and protected cultivation systems under the impact of climatic change in vulnerable areas, including the Mediterranean region.

The influence of thermal stress on the physical and technical activities of soccer players: lessons from the 2018 FIFA World Cup in Russia

The present study attempts to assess changes in soccer players’ physical and technical activity profiles due to thermal stress, measured with the Universal Thermal Climate Index (UTCI), in training centres and during matches of the 2018 FIFA World Cup in Russia. The study also verifies the theoretical models of soccer players’ physiological parameters. The study sample consisted of 945 observations of 340 players of national teams taking part in the World Cup in Russia. The measured variables included physical activities: total distance covered, distances covered with an intensity of 20–25 km/h, number of sprints; technical activities: number of shots, number of passes, pass accuracy and physiological indicators: evaporative water loss and heart rate. In addition, the final ranking places of each national team were also used in the study. The UTCI was calculated based on meteorological data recorded at training centres and during matches. The UTCI records were then classified into two ranges: NTS—no thermal stress (UTCI 9–26 °C) and TS—thermal stress (UTCI > 26 °C). Climatic conditions at soccer training centres assessed as involving “no thermal stress” are found to be more beneficial for increasing the total distance covered and the number of sprints performed by players during a match. The theoretical models for determining soccer players’ physiological parameters used in the study reduce the players’ heart rate effort and evaporative water loss, which is in line with findings in studies by other authors. The climatic conditions at soccer training centres and during tournament matches should be taken into account in planning preparations for future World Cup tournaments, especially those in hotter countries.

Water loss and temperature interact to compound amphibian vulnerability to climate change.

Ectotherm thermal physiology is frequently used to predict species responses to changing climates, but for amphibians, water loss may be of equal or greater importance. Using physical models, we estimated the frequency of exceeding the thermal optimum (Topt ) or critical evaporative water loss (EWLcrit ) limits, with and without shade- or water-seeking behaviours. Under current climatic conditions (2002-2012), we predict that harmful thermal (>Topt ) and hydric (>EWLcrit ) conditions limit the activity of amphibians during ~70% of snow-free days in sunny habitats. By the 2080s, we estimate that sunny and dry habitats will exceed one or both of these physiological limits during 95% of snow-free days. Counterintuitively, we find that while wet environments eliminate the risk of critical EWL, they do not reduce the risk of exceeding Topt (+2% higher). Similarly, while shaded dry environments lower the risk of exceeding Topt , critical EWL limits are still exceeded during 63% of snow-free days. Thus, no single environment that we evaluated can simultaneously reduce both physiological risks. When we forecast both temperature and EWL into the 2080s, both physiological thresholds are exceeded in all habitats during 48% of snow-free days, suggesting that there may be limited opportunity for behaviour to ameliorate climate change. We conclude that temperature and water loss act synergistically, compounding the ecophysiological risk posed by climate change, as the combined effects are more severe than those predicted individually. Our results suggest that predictions of physiological risk posed by climate change that do not account for water loss in amphibians may be severely underestimated and that there may be limited scope for facultative behaviours to mediate rapidly changing environments.