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In this study, a looplike dynamic network data envelopment analysis (DEA) framework is proposed to assess technical efficiency in Germany's water economy at the federal state level. In the wake of growing political attempts in Europe to strengthen circular, sustainability-oriented practices in a variety of economic realms, our tailored approach enables, arguably for the first time, simultaneous analysis of public water provision, wastewater services and natural water endowment while accounting for water demand in an encompassing feedback-type context. Our model addresses the issues of water sector infrastructure and environmental sustainability. By measuring divisional efficiencies in addition to composite network efficiency over time, we extend previous static 'black box' DEA studies to provide comprehensive and in-depth insight into water economy dynamics. Our framework goes beyond the existing models by unifying distinct yet interrelated water economy processes under an encompassing circular technical efficiency evaluation paradigm to underpin holistic, environmentally-prudent water resource management concerning infrastructure, production, consumption, cleaning, recycling and reuse. Our empirical case study reveals high levels of efficiency in Germany on the whole, and we find little variation among regions in terms of composite water economy efficiency. The natural water endowment segment, which correlates more strongly with the overall water economy than any other network component, exhibits considerable efficiency score volatility. Furthermore, we find that the wastewater treatment section harbours many best-practice regions. Our results also show that the most substantial performance-optimising input reduction required pertains to land area consisting of vegetation and water, which suggests both natural resource endowment efficiency underperformance and sustainability overachievement in the sense of an excess capacity to free up resources for other uses. The largest output increase called for concerns consumers, with regard to water sector value added. Regional water sector infrastructure utilisation appears to be generally adequate, although several federal states fail to meet the optimal levels. [Display omitted] • We tailor a looplike dynamic network DEA model to assess water economy performance. • Our approach captures the objectives of resource circularity and sustainability. • Our analysis offers deep insight into water economy patterns in Germany over time. • Our study enables integrated policy action based on holistic resource management. [ABSTRACT FROM AUTHOR]

Studies on water balance in desert-dwelling granivorous rodents use evaporative water loss (EWL) and metabolic water production (MWP) to evaluate the efficiency of water regulation, expressed by the model Ta @ MWP = EWL, defined by an ambient temperature (Ta) value at (@) which MWP/EWL = 1. Here we evaluate and apply this model (1 - r²) determining water regulation efficiency, based on the energetic cost (MR) to maintain water balance (WB), that is MR-WB. To test the model, EWL was measured and MWP estimated in nine species of rodents from different localities of northern and north-central Chile (II and IV Regions): Octodon degus (Od) and O. lunatus (Olu) (Octodontidae), Abrothrix olivaceus (Ao), A. longipilis (Al), A. andinus (Ad), Phyllotis darwini (Pd), P. rupestris (Pr), P. magister (Pm), Oligoryzomys longicaudatus (Ol) (Muridae) and Chinchilla lanigera (Cl) (Chinchillidae). Literature information on rodents from xeric and mesic habitats was also analyzed. Results indicate that: 1) Cl has the lowest EWL (0.58 mg H2O/g h), followed by Od < Olu < Ao < Pd < Pm < Pr < Ad < Al < Ol. 2) EWL and body mass (M) are related through independent equations considering two distinctive habitats: EWL (xeric)= 5.968 M-0.416 (r = -0.89; P < 0.001) and EWL (mesic) = 17.272 M -0.532 (r = -0.85; P < 0.001). 3) MWP and M are related through the equation: MWP = 14.256 M--0.539 (r = - 0.98; P< 0.001). 4) At the intraspecific level , MWP/EWL and Ta are related through a negative exponential equation: MWP/EWL=a 10-bTa (r = -0.95; P< 0.001). 5) Ta @ MWP = EWL and M are related through the equation: T @ (MWP = EWL) = 26.799 M-0.142, (r = - 0.49, P < 0.02). 6) MR-WB and M, are related through independent equations according to the prevailing animal's habitat : MR - WB (xeric) = 34.627 M-0.339 (r = - 0.93; P < 0.001) and MR-WB (mesic) = 68.132 M-0.381 (r = -0.86; P < 0.001). These last two equations have comparative advantages to the previous ones because they include rodents with different dietary habits, are able to discriminate patterns in the water regulation efficiency as a function of different habitats (xeric and mesic), and enable to evaluate the energetic cost of water balance.Para evaluar la eficiencia en la regulación hídrica de roedores granívoros desertícolas se usa la pérdida de agua por evaporación (EWL) y la producción de agua metabólica (MWP), estando esta expresada por el modelo Ta @ MWP = EWL, que representa el valor de una temperatura ambiente (Ta) al cual (@) MWP/EWL = 1. En este trabajo se evalua este modelo (1- r²) y se estima la eficiencia en la regulación de agua basados en el costo energético (MR) de mantención del balance hídrico (WB), es decir MR-WB. Se midió EWL y se estimó MWP en las siguientes nueve especies de roedores de diferente localidades del norte y centro de Chile (Regiones II y IV): Octodon degus (Od) y O. lunatus (Olu) (Octodontidae), Abrothrix olivaceus (Ao), A. longipilis (Al), A. andinus (Ad), Phyllotis darwini (Pd), P. rupestris (Pr), P. magister (Pm), Oligoryzomys longicaudatus (Ol) (Muridae) and Chinchilla lanigera (Cl) (Chinchillidae). Se analizó además información de la literatura de roedores de hábitats xericos y mesicos. Los resultados indican que: 1) Cl posee la menor EWL (0,58 mg H2O/g h), seguido por Od < Olu < Ao < Pd < Pm < Pr < Ad < Al < Ol. 2) EWL y masa corporal (M) se relacionan a través de ecuaciones independientes que consideran dos hábitats distintos: EWL (xérico)= 5,968 M-0,416 (r = -0,89; P < 0,001) y EWL (mésico) = 17,272 M -0,532 (r = -0,85; P < 0,001). 3) MWP and M se relacionan por la ecuación: MWP = 14,256 M-0,539 (r = - 0,98; P < 0,001). 4) A un nivel intraespecífico, MWP/EWL y Ta se relacionan a través de una ecuación exponencial negativa: MWP/EWL=a 10-bTa (r = -0,95; P < 0,001). 5) Ta @ MWP = EWL y M se relacionan a través de la ecuación: Ta @ (MWP = EWL) = 26,799 M-0,142, (r = - 0,49, P < 0,02). 6) MR-WB y M, se relacionan por ecuaciones hábitats-dependientes y son: MR - WB (xérico) = 34,627 M-0,339 (r = - 0,93; P < 0,001) y MR-WB (mésico) = 68,132 M-0,381 (r = -0,86; P < 0,001). Estas dos últimas ecuaciones poseen ventajas comparativas con respecto a las anteriores pues incluyen roedores con diferentes hábitos dietarios, son capaces de discriminar patrones de regulación hídrica en función del hábitat (xérico y mésico), y son capaces de evaluar el costo energético del balance hídrico

In paper are evaluated social and economical changes in water economy with emphasis on complex evaluation of municipal cleaners waste waters with respect of legislative, position of ownerskip relationskips and financial security of public experiences of water economy.

It was performed an statistical analysis about the water's management and agricultural productivity, developed in the irrigation module 063 in the cycles 2007 to 2012. The profit per hectare was calculated. It was found that corn, chickpea and beans offered profit margins but with important differences in the water consumption. Regarding to the water management per module, the results showed that there weren't significative differences in the water suminister but in its productivity. Based on it, is proposed to reconsider the hydro agricultural programming in support to the statistical analysis and in times of scarcity, be able to have alternative proposals representing a viable choice for farmers. [ABSTRACT FROM AUTHOR]

Water is critical for viticulture sustainability since grape production, quality and economic viability are largely dependent on water availability. The total water consumption of vineyards, 300 to 700 mm, is generally higher than the annual average precipitation in many viticultural areas, which induces a risk for sustainability of vineyards. Improving vineyard water use efficiency (WUE) is therefore crucial for a sustainable viticulture industry in semi-arid regions. Increased sustainability of water resources for vineyards can be achieved using both agronomical technology and cultivar selection. Here, we review advances in grapevine water use efficiency related to changes in agronomical practices and genetic improvements. Agronomical practices focus on increasing green water use by increasing soil water storage capacity, reducing direct soil water loss, or limiting early transpiration losses. Cover crops for semi-arid areas show a favorable effect, but careful management is needed to avoid excessive water consumption by the cover crop. Canopy management practices to reduce excessive water use are also analyzed. This is a genetic based review focused on identifying cultivars with higher WUE. [ABSTRACT FROM AUTHOR]

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There is various evidence that the presence of condensed water, e.g. dew, improves plant water relations. Because particularly plants in drier environments are expected to benefit from atmospheric water, it may be assumed that special adaptations promoting exploitation of dew water evolved in these habitats. Surface characteristics affect dewfall and retention of dew water. Leaf surface characteristics such as hairs (trichomes), which are often present in plants of arid environments, may therefore play a substantial role in dew harvesting. In this study, it is analysed to what extent (1) the presence of hygrophilic aerosoles promotes dewfall by reducing vapour saturation pressure ('early condensation'), (2) dew water can be stored within a dense trichome layer, (3) the presence of dew water increases humidity directly above the leaf surface, thereby reducing water loss from the leaf interior by decreasing the water potential gradient between leaf interior and exterior, and (4) dew evaporation reduces transpiration further by evaporative cooling. A physical framework is provided in this contribution that shows that these processes are in fact possible under natural conditions. [ABSTRACT FROM AUTHOR]

Dense moss cushions colonize bare limestone pavements on Öland's alvar, southeastern Sweden. As these cushions grow larger and thicker and can store more water, they should physically protect and facilitate their own performance as well as the colonization by vascular plants. We tested these predictions by measuring the airflow and water economy of moss cushions. We found that cushions are imbedded in boundary layers formed by ground and moss surfaces. Near-surface flow was reduced immediately upwind and negligible downwind of the moss cushions, which should facilitate their centrifugal expansion. The calculated diffusion boundary layer was thin (<0.7 mm) above moss cushions exposed to free airflow of 1-6 m·s−1 in accordance with substantial turbulence measured by small sensors at 0.5 cm distance from moss surfaces. Evaporation from the wetted cushions increased linearly with wind speed (0 and 8 m·s−1) in wind-tunnel experiments, and neither evaporation nor airflow followed standard formulas for objects in free flow. Higher wind speed reduced the diffusion boundary layer and simultaneously cooled the moss surface, thereby reducing the drop in water vapour concentration from moss surfaces to air. As desiccation of cushions progressed during three dry summer days, the profound decline of evaporation rate with cushion size gradually became positive when only large cushions still contained water. Water economy in relation to cushion size predicted that rehydrated large cushions retained photosynthesis for 80% and small cushions for only 50% of the time. A cover of the succulent plant Sedum album L. reduced sun and wind exposure and water loss from the moss surface. Sedum remained hydrated after mosses had dried out. Moss cushions and Sedum can, therefore, mutually benefit from each other's water economy. [ABSTRACT FROM AUTHOR]

Abstract: The data on Scots pine responses to elevated ozone (O3) mainly come from experimental studies with young seedlings and trees. Based on the 38 experiments reviewed here, Scots pine may be considered as an O3-sensitive conifer species, with mature pines more sensitive than younger trees. This is due to their relatively small proportion of current (c) year needles with the highest photosynthetic capacity. Moreover, young seedlings and trees seem to acclimate to slightly elevated realistic O3 exposures, and hence do not often exhibit growth and biomass reductions in spite of the visible and microscopic needle injuries and changes in needle chemistry. The O3 sensitivity in Scots pine is thought to relate to impaired water status due to the malfunction of stomata and subsequent increase in transpiration. This may lead to reduced wood biomass in the long term, if Scots pines try to maximise the biomass of c needles and root biomass to maintain efficient water and nitrogen (N) supply to support the photosynthesis of c needles. Tree water status also contributes to the spring-time recovery of photosynthesis. We call especially for studies on atmosphere–needle surface interaction that would yield novel information on the impact of O3 on epicuticular waxes and stomatal functioning, which both regulate O3 flux and tree water status and hence also modify photosynthesis. The need for flux-based field studies is especially important in the light of future climatic change, since the risk presented by O3 to Scots pine forests in Northern and Central Europe seems to be equal. [Copyright &y& Elsevier]

Abstract: We examine here the thermal physiology of the ash-grey mouse, as there is a paucity of data to explain how Australian rodents meet thermoregulatory demands. Most ash-grey mice remained normothermic over a range of ambient temperatures (10°C to 30°C), although they became hyperthermic at high ambient temperatures. One individual entered torpor at ambient temperatures of 20°C and 25°C, with minimal body temperatures of 24.5°C and 28.4°C respectively, before spontaneously arousing. This is the first evidence of torpor use by an Australian murine rodent. Our data suggest that although ash-grey mice have the physiological ability to use torpor, it is used rarely, presumably due to other behavioural and physiological adaptations. Their higher-than-expected basal metabolic rate (1.56±0.25mLO2 g−1 h−1) indicates that ash-grey mice do not have a frugal approach to energy expenditure. Other standard physiological variables were typical of a generalised rodent. A readily-available omnivorous diet, nocturnal activity, semi-fossorial habit and social behaviour presumably allow a high energy lifestyle. A reluctance to use torpor, despite an apparent physiological ability to do so, supports the idea that the use of torpor reflects a net balance between the costs and benefits of a heterothermic thermoregulatory strategy. [Copyright &y& Elsevier]

Dense moss cushions of different size are distributed across the bare limestone pavements on Øland, SE Sweden. Increasing cushion size is predicted to physically protect and improve performance and colonization by vascular plants. Therefore, we tested water balance, phosphorus supply, and species richness, and evaluated duration of plant activity during desiccation as a function of ground area, for a large collection of moss cushions. We found that lower evaporation and higher water storage contributed equally to extending the desiccation period with increasing cushion size. Evaporation rates declined by the −0.36 power of cushion diameter, and were not significantly different from −0.50 for the square root function previously predicted for the increasing thickness of the boundary layer, with greater linear dimensions for smooth flat objects at low wind velocities. Size dependence vanished under stagnant conditions. One moss species was added to the species pool for every nine-fold increase in cushion area. Vascular plants were absent from the smallest cushions, whereas one or two species, on average, appeared in 375- and 8,500-cm cushions with water available for 6 and 10 days during desiccation. Phosphorus concentrations increased stepwise and four-fold from detritus to surface mosses and to vascular plants, and all three pools increased with cushion size. We conclude that cushion mosses and cushion size play a critical role in this resource-limited limestone environment by offering an oasis of improved water and nutrient supply to colonization and growth of plants. [ABSTRACT FROM AUTHOR]

We examine here evaporative water loss, economy and partitioning at ambient temperatures from 14 to 33°C for the monito del monte (Dromiciops gliroides), a microbiotheriid marsupial found only in temperate rainforests of Chile. The monito's standard evaporative water loss (2.58 mg g-1 h-1 at 30°C) was typical for a marsupial of its body mass and phylogenetic position. Evaporative water loss was independent of air temperature below thermoneutrality, but enhanced evaporative water loss and hyperthermia were the primary thermal responses above the thermoneutral zone. Non-invasive partitioning of total evaporative water loss indicated that respiratory loss accounted for 59-77% of the total, with no change in respiratory loss with ambient temperature, but a small change in cutaneous loss below thermoneutrality and an increase in cutaneous loss in and above thermoneutrality. Relative water economy (metabolic water production/evaporative water loss) increased at low ambient temperatures, with a point of relative water economy of 15.4°C. Thermolability had little effect on relative water economy, but conferred substantial energy savings at low ambient temperatures. Torpor reduced total evaporative water loss to as little as 21% of normothermic values, but relative water economy during torpor was poor even at low ambient temperatures because of the relatively greater reduction in metabolic water production than in evaporative water loss. The poor water economy of the monito during torpor suggests that negative water balance may explain why hibernators periodically arouse to normothermia, to obtain water by drinking or via an improved water economy. [ABSTRACT FROM AUTHOR]

Abstract: Rockskippers (family Blenniidae) and mudskippers (family Gobiidae) are amphibious fishes common to tropical intertidal zones. While their emergence patterns differ, both groups spend considerable time on land where they are subject to desiccation. Using a gravimetric wind tunnel method we determined total and cutaneous resistance to evaporative water loss of lined, Istiblennius lineatus (Valenciennes in ), and Ambon, Paralticus amboinensis (Bleeker, 1857), rockskippers as well as barred, Periophthalmus argentilineatus Valenciennes in , and common, Periophthalmus kalolo Lesson, 1831, mudskippers from Hoga Island, southeast Sulawesi, Indonesia. These fishes exhibited mean total resistance values ranging between 0.82 and 0.61s/cm; values significantly higher than their agar replicas. Mean cutaneous resistance estimates ranged from 0.38 to 0.25s/cm. Total and cutaneous resistances were statistically similar between species (p =0.125 and 0.480, respectively). Water loss resistance, while marginal, likely plays an important role in extending fish emergence times. Having greater resistance values may not be compatible with cutaneous respiration or necessary for fishes that frequently return to pools to eliminate nitrogenous wastes. This is the first direct evidence of evaporative water loss resistance in fishes. [Copyright &y& Elsevier]

Change in leaf form or shape has often been enumerated as a potential means of reducing transpiration by plants experiencing water deficit. Because leaf rolling is the first and foremost visible physiological response to water deficit in rice plant, its dynamic nature and impact on leaf water homeostasis and water conservation were studied in hybrid rice (Oryza sativa L.) in depth. Marked diurnal fluctuations were observed in leaf rolling behavior over short as well as extended periods of time during the drying cycle. Leaves were found unrolled (open) during early and late hours of the day in watered plants, whereas stressed plants exhibited partial rolling (score >3) even in the morning, followed by complete rolling at noon (score 5). The rolling of leaves of watered plants fluctuated within a very narrow range (between score 1 to 2) throughout 20 days of drying cycle, whereas stressed plants, although they did not differ from control plants during the first 5 days of stress, displayed wide fluctuations thereafter, culminating into complete rolling (score 5) with no further diurnal variations in space and time. The pattern of changes in leaf water potential closely followed leaf rolling behavior. Examination of leaves by naked eye and hand lens revealed two distinct textures of surfaces in a given leaf blade, i.e. smooth or ridged, located opposite to each other on either side of the midrib. Quite often, the ridged portion rolled first, followed by the smooth one rolling over the former during the drying cycle as the water potential of the ridged portion was less by 0.48 MPa than the smooth portion at the completion of leaf rolling (score 5). Similarly, the water potential of the apical half portion of the leaf blade was less by 0.41 MPa in comparison with the basal half. In the main, two types of leaf rolling were observed: one was classified as acropetal, which consisted of helical and non-helical rolling, and the other was non-acropetal, characterized by either the ridged portion bending first or ridged and smooth portions bending almost simultaneously. Leaf rolling in etiolated leaves was quicker by 14 min than the green ones; however, darkness delayed the rolling (score 5) of green leaves by 32 min. The rate of transpiration decreased by 52% in manually rolled, excised turgid leaves, which reversed back to the initial rate of water loss once the leaves were unrolled (open). In the absence of water supply to the excised leaves, the spontaneously rolled leaves exhibited 87% water saving (only 13% loss in fresh weight) against 68% saving (32% loss) by leaves mechanically prevented from rolling, suggesting its important role in leaf water homeostasis and water economy during limited-water supply conditions. The findings carry biotechnological applications that may further provide important information for the design of strategies for future engineering of an improved external plant defense system against drought with increased water-use-efficiency in hybrid and super hybrid rice. [ABSTRACT FROM AUTHOR]

Abstract: We compared geographic trends in body mass in a number of populations of the olivaceous field mouse (Abrothrix olivaceus,) along a latitudinal gradient in Chile, and tested the expected neutral tendency resulting from the opposite influences of environmental temperature and aridity across the gradient. Also, we studied water economy through physiological measurements of total evaporative water loss and urine osmolality in individuals from populations inhabiting two contrasting habitats (northern semiarid shrubland and southern temperate rainforest) and acclimated during six months to the same conditions. No change in male body mass with latitude was found across 39 populations. Evaporative water loss in rodents from the semiarid shrubland was significantly lower than that of individuals from the temperate rainforest, and urine osmolality was significantly higher in rodents from the semiarid habitat. We found a better tolerance of water shortage in the rodent population from the xeric habitat, thus suggesting the occurrence of local adaptation to the prevailing habitat conditions. The mechanisms by which rodents regulate their water economy in face of spatial and temporal fluctuations in environmental conditions constitute an essential component of the physiological flexibility that is necessary to cope with challenging climate change scenarios. [Copyright &y& Elsevier]

The aim of this study was to detect suites of traits related to whole plant and seed morphology, phenology and resource use – including water – in species differing in successional status. Twenty traits were measured on 55 species representative of 5 successional stages in Mediterranean southern France, including eight pertaining to phenology and five to water economy. Suites of traits that changed along succession in agreement with the acquisition/conservation trade-off were completed by continuous changes in phenology. Early successional species had leaves with a high specific leaf area that were produced and lost continuously through the growing season. Late-successional species were taller with long-lived, high δ13C leaves produced during short periods, most of them persisting during summer, and produced large seeds requiring a long ripening period. Replacement of species occurred with change in strategies of drought survival: early successional species escaped drought by dying before summer; later herbaceous species maintained favourable water status in relation to leaf shedding during summer; late successional trees with a large body allowing access to a large pool of resources, produced dense leaves that could tolerate desiccation. These changes occurred concomitantly with a shift in CSR strategies, using traits related to resource use, plant size and flowering phenology: ruderal herbs were replaced by more stress-tolerant herbs and shrubs throughout the succession, with competitive trees dominating the latest successional stage. These results suggest that the breadth of functional variability found in natura is not predicted by the CSR framework, and calls for a more integrated view of whole plant functioning. [ABSTRACT FROM AUTHOR]

The honey possum is the only non-volant mammal to feed exclusively on a diet of nectar and pollen. Like other mammalian and avian nectarivores, previous studies indicated that the honey possum’s basal metabolic rate was higher than predicted for a marsupial of equivalent body mass. However, these early measurements have been questioned. We re-examined the basal metabolic rate (2.52 ± 0.222 ml O2 g−1 h−1) of the honey possum and confirm that it is indeed higher (162%) than predicted for other marsupials both before and after accounting for phylogenetic history. This, together with its small body mass (5.4 ± 0.14 g; 1.3% of that predicted by phylogeny) may be attributed to its nectarivorous diet and mesic distribution. Its high-basal metabolic rate is associated with a high-standard body temperature (36.6 ± 0.48°C) and oxygen extraction (19.4%), but interestingly the honey possum has a high point of relative water economy (17.0°C) and its standard evaporative water loss (4.33 ± 0.394 mg H2O g−1 h−1) is not elevated above that of other marsupials, despite its mesic habitat and high dietary water intake. [ABSTRACT FROM AUTHOR]

Abstract: We present here the first physiological data for the sandhill dunnart (Sminthopsis psammophila), the second largest (35–44 g) sminthopsine dasyurid marsupial, and report torpor for this species. Their thermoneutral body temperature (34.4 °C), thermolability below thermoneutrality (0.062 °C °C−1), and mild hyperthermia above thermoneutrality (35.5 °C) are typical of small dunnarts, and dasyurids. Basal metabolic rate (0.80 mL O2 g−1 h−1) is as predicted from mass. Sandhill dunnarts generally conform to the Scholander–Irving model of endothermy, although metabolism increases less than expected and extrapolates to a higher than actual body temperature. Wet (0.22 mL O2 g−1 h−1 C−1) and dry (2.8 J g−1 h−1 °C−1) thermal conductances were as predicted. Thermoneutral evaporative water loss (1.6 mg g−1 h−1) was only 54% of expected, but this is not significantly different, and more likely reflects variability in the marsupial dataset than an adaptation. Relative water economy resembles that of other small marsupials, rodents and birds, with a point of relative economy of 18 °C. Respiratory ventilation closely matches metabolic rate, with minute volume increased at low ambient temperatures by increased breathing rate rather than tidal volume; oxygen extraction was constant at about 17%, except during hyperthermia above the thermoneutrality. Torpor conferred significant energetic and hygric benefits. We found no evidence of deviation from allometrically- and phylogenetically-based expectations despite the sandhill dunnart''s arid habitat and large (for a dunnart) body mass. [Copyright &y& Elsevier]

An experiment was conducted during summer and kharif seasons of 2004 and 2005 at Agricultural Research Station, Bhavanisagar, to study different irrigation methods and regimes (IW/CPE ratio) on yield attributes, yield and water economy in hybrid sunflower (MSFH 17). Yield and yield attributes varied significantly during both summer and kharif seasons of 2004 and 2005. Irrigation at 0.80 and 0.60 IW/CPE ratios under alternate furrows and paired row system of irrigation (80/40 x 30 cm) proved better than other treatment combinations with regard to water use efficiency gross return, net return and B0 : C ratio. [ABSTRACT FROM AUTHOR]

A large number of physiological acclimation studies assume that flexibility in a certain trait is both adaptive and functionally important for organisms in their natural environment; however, it is not clear how an organism’s capacity for temperature acclimation translates to the seasonal acclimatization that these organisms must accomplish. To elucidate this relationship, we measured BMR and TEWL rates in both field-acclimatized and laboratory-acclimated adult rufous-collared sparrows ( Zonotrichia capensis). Measurements in field-acclimatized birds were taken during the winter and summer seasons; in the laboratory-acclimated birds, we took our measurements following 4 weeks at either 15 or 30°C. Although BMR and TEWL rates did not differ between winter and summer in the field-acclimatized birds, laboratory-acclimated birds exposed to 15°C exhibited both a higher BMR and TEWL rate when compared to the birds acclimated to 30°C and the field-acclimatized birds. Because organ masses seem to be similar between field and cold-acclimated birds whereas BMR is higher in cold-acclimated birds, the variability in BMR cannot be explained completely by adjustments in organ masses. Our findings suggest that, although rufous-collared sparrows can exhibit thermal acclimation of physiological traits, sparrows do not use this capacity to cope with minor to moderate fluctuations in environmental conditions. Our data support the hypothesis that physiological flexibility in energetic traits is a common feature of avian metabolism. [ABSTRACT FROM AUTHOR]

• Development of a composite indicator to measure the quality of water supply based on variables that are considered to affect users' perceptions of the quality of water supply. • A CI that includes relevant aspects that determine users' perceptions of water supply quality. • A new CI application, using MCDA with common DEA weights, to calculate a proxy for water supply service quality. • A CI that combines economic, technical and service quality variables, as they may be perceived by users, into a single indicator for water managers. The objective of this study is to develop a composite indicator (CI) to measure the quality of water supply based on the variables that are considered to affect users' perceptions of water supply quality. The proposed CI includes six relevant aspects that determine users' perceptions of water supply quality (network quality, water quality, water price, complaints, inconvenience caused by upgrading the network, and continuity of service) in a simple, economical, and objective way, using multi-criteria decision analysis (MCDA) with weights based on data envelopment analysis (DEA). The CI was applied to 32 municipalities in the metropolitan area of Valencia (Spain). The results show the high quality of the water supply service in this area. The use of this CI to measure the quality of the water supply service may prove useful for public institutions and managers of urban water supply, giving them an instrument to improve the management, efficiency, and quality of the water services they provide. [ABSTRACT FROM AUTHOR]

Abstract: We compared the efficiency of water regulation of two rodent species—Phyllotis xanthopygus rupestris and Phyllotis darwini, inhabiting contrasting habitats in South America. We evaluated water requirements ad libitum, resistance index to water deprivation (water deprivation test), evaporative water loss, and renal morphology. Water consumption of P. x. rupestris was significantly higher than in P. darwini, P. x. rupestris and P. darwini subjected to water deprivation, showed a negative relationship between body mass loss and water deprivation time. Minimal evaporative water loss values were not significantly different between species. Although P. x. rupestris and P. darwini were not able to maintain their body mass under water deprivation tests, they have different water economies. This suggests that due to their distinct inhabitats with contrasting water availability, they have different adaptative strategies in their respective environments. [Copyright &y& Elsevier]

Abstract: Rodents from arid and semi-arid deserts are faced with the problem of water conservation. The physiological responses of small rodents to such conditions have been intensively investigated over broad geographically disjunct areas. Despite the presence of xeric habitats in South America since the late Tertiary, some studies suggest that sigmodontine South-American desert rodents do not display the same diversity of physiological responses at the species level as those observed in other desert-dwelling species of rodents. In this paper, we analyzed the physiological responses to water deprivation, at the interespecific and interindividual level, among eight species of sigmodontine desert-dwelling rodents from different geographical areas within South-American deserts. Using randomization tests, we found no significant phylogenetic signal for resistance to water deprivation or for individual variability in this response. Contrary to our initial predictions, we observed that sigmodontine rodents from arid/semi-arid habitats (Monte Desert) had significantly lower rates of body mass loss per day (higher tolerances to water deprivation) than species from the hyperarid deserts. We showed that sigmodontine rodents from South America showed a remarkable diversity of physiological mechanisms for coping with water shortage resulting from different evolutionary adaptive strategies. This diversity, however, displays a rather unexpected pattern in terms of its geographical distribution. [Copyright &y& Elsevier]

Abstract: Lagidium viscacia inhabits where water and food availability is low. We hypothesize that this rodent should minimize metabolic rate and water loss in order to cope with such extreme environments. We observed that Lagidium viscacia has (1) a comparatively lower basal metabolic rate (67%) and thermal conductance (78%) of predicted; (2) a higher pulmocutaneous evaporation rate which is 36% (mesic) and 63% (xeric); and (3) energetic cost of maintaining the water balance similar to that expected for rodents from xeric environments (2.8cal/gh). In summary, Lagidium viscacia has physiological traits that favour energy and water economy to cope with such extreme habitats. [Copyright &y& Elsevier]

Animals inhabiting xeric environments use a variety of behavioral and physiological strategies to balance water budgets. We studied the potential contribution of the urinary bladder to osmoregulation in a large desert lizard, the Gila monster Heloderma suspectum. Here we present results of a series of in vivo laboratory experiments which tested the hypothesis that the Gila monster urinary bladder serves as a physiological reservoir, as in amphibians and chelonians, providing water that buffers increases in plasma osmolality when food and water are unavailable. Adult Gila monsters absorbed water from the urinary bladder into circulation and absorption of water from the urinary bladder and drinking water provided similar osmoregulatory benefits within 24 h, although drinking water provided a more immediate osmotic benefit. During food and water deprivation, plasma osmolality increased 2.5 times faster in lizards with an empty urinary bladder compared with those with a full bladder. During rehydration, stereotyped binge drinking behavior increased body mass nearly 22%, which resulted in a 24% reduction in plasma osmolality and a substantial increase in bladder water within 24 h. These results support our hypothesis and demonstrate for the first time in an adult lizard that the urinary bladder can function as a long-term physiological water reservoir. This trait can provide a critical benefit to osmoregulation during the 2- to 3-month summer dry season characteristic of the deserts that Gila monsters inhabit. [ABSTRACT FROM AUTHOR]