Submergence In Water Research Articles

Melatonin integrates multidimensional regulation of Na+/K+-ATPase in ionocytes and promotes stress and ease response in hypoxia-induced air-breathing fish: lessons from integrative approach.

As circadian regulator, melatonin is involved in many physiological processes including ionosmotic regulation in fishes. Na+/K+-ATPase (NKA), an ubiquitous Na+/K+ transporter in ionocyte epithelia that drives electrochemical Na+ gradients and systemic osmotic integration, is a target of stress in fish. However, it is not certain how melatonin regulates NKA functions in ionocyte epithelia and how it modulates the adaptive response such as stress and ease response in fish particularly in hypoxia condition. We, thus, examined the short-term in vivo action of melatonin on the dynamics of NKA regulation in branchial, renal and intestinal ionocytes of hypoxia-induced air-breathing fish (Anabas testudineus Bloch). Interestingly, we found a rise in plasma melatonin in fish when kept for 30min of forced submergence in water and that indicates a role for melatonin in hypoxia tolerance. A fall in blood [Na+ , K+] occurred in these hypoxic fish which later showed a recovery after melatonin treatment. Similarly, melatonin favored the fall in NKA activity in branchial and renal epithelia of hypoxic fish, though it remarkably stimulated its activities in non-stressed fish. Likewise, melatonin that produced differential pattern of mRNA expression in nkaα1-subunit isoforms (nkaα1a, nkaα1b and nkaα1c) and melatonin receptor isoforms (mtnr1a, mtnr1bb, mtnr1bb x1x2 ) in the tested ionocyte epithelia, showed reversed expression in hypoxic fish. In addition, the rise in NKAα-protein abundance in branchial and renal epithelia of melatonin-treated hypoxic fish indicated a recovery action of melatonin. A higher NKAα-immunoreactivity was found in the immunohistochemical and immunofluorescent images of branchial ionocytes and renal proximal and distal ionocytes of hypoxic fish treated with melatonin. Furthermore, an activation of PKA and PKG-dependent phosphorylation was found in branchial epithelia of hypoxic fish. The generated integrative parabola model showed that melatonin has a maximum targeted action on NKA function in the renal epithelia, suggesting its lead role in the integration of ionosmotic balance during the recovery or ease response. Over all, the data indicate a multidimensional and preferential action of melatonin on NKA regulation in fish ionocytes that integrate the recovery action against hypoxia, thus pointing to a major role for melatonin in stress and ease response in this fish.

OPTIMIZING CEMENT KILN DUST DENSITY TO IMPROVE LANDFILL AIR SPACE UTILIZATION

Optimizing the density of waste materials in landfills by proper compaction prolongs the facility life due to the efficient use of landfill airspace. Cement kiln dust (CKD) is a waste by-product produced in huge amounts which exceeds the used quantities in the cement recycling industry and beneficial CKD applications. The vast amount of CKD is almost landfilled in its loose state in Egypt which causes a big loss in landfill airspace due to the low density of CKD. The hydraulic binder effect and dusty behavior of reactive CKD complicates its compaction process. Accordingly, this research was performed to investigate CKD compaction properties with three types of lubricants, which are potable water, salt water and waste oil. Maximum dry density (MDD) and optimum moisture content (OMC) for these lubricant types and different wetting methods were investigated in order to improve the landfill air space utilization and to reduce the dusty effect of CKD during compaction. The effect of immediate compaction after wetting and the effect of compaction delay by allowing CKD to hydrate initially for a certain period were studied. Compaction energy and methods of the wetting of CKD either by full submergence in water or prewetting were tested. The maximum weights of a disposed CKD and durations required to fill an intended landfill air space for different CKD conditions, lubricant types and compaction methods were presented for a case study in Ain Sokhna, Egypt.

Mechanical Strength and Water Transport Properties of Concrete Containing Treated Recycled Aggregates

Objective: The objective is to determine the effect of treated RCA on the mechanical strength of hardened concrete, and determine the influence of treated RCA on water transport within the matrix of hardened concrete. Aim: The study aims to use pozzolanic concentration of cement and RHA slurry to pretreat coarse RCA for full replacement of NCA for sustainable concrete production. Background: One of the common modes of disposal of construction waste is strained landfills. This study proposes a constructive way of recovering the coarse aggregates of recycled aggregates from laboratory concrete waste taken through a focused treatment process with pozzolan. The study aims to replace the proportions of the cement slurry to treat and replace with rice husk ash (RHA) for the modification of recycled concrete aggregate (RCA) and replace fully natural coarse aggregate (NCA) for sustainable concrete production. One of the main challenges of recycled concrete aggregate (RCA) is the fractured surface, which often results in reduced strength and loss of concrete durability. The strength of concrete with RCA is principally influenced by the fractured hardened paste attached to the surface, predominantly characterized by voids and gaps resulting from its production using a mechanical method. High water penetration within and around the aggregate matrix due to the presence of micro- and macro-cracks results in strength and durability deterioration of concrete. Methods: This study addresses these problems by specifying aggregate treatment with a pozzolanic slurry of cement and RHA. This was conducted in two (2) phases; first, to determine the optimum proportion of cement slurry concentration (0, 20, 40, 60, 80, and 100%), and second, to increase the silicate formation in cement slurry by substituting the proportions of cement with RHA (0, 5, 10, and 15%). The performance of concrete was evaluated by mechanical strength (compressive and split tensile strength) at 7, 28, and 56 days and water transport within the concrete (surface suction and submergence) at 28 and 56 days of curing age. Results: The use of cement slurry treatment at various concentrations generally increased compressive strength at 28 days compared to untreated RCA. The findings show that at a 20% concentration of cement slurry, the increase in compressive strength is 38.4%. Upon replacement of cement in treatment slurry of RCA with 5% RHA, the increase in compressive strength was 61%, while the split tensile strength increased by 10.2%. The amount of water absorbed was observed after 30 minutes of full submergence in water, indicating that samples with 20% cement concentration at 28 days resulted in the lowest water absorption of 2.01%. However, with the replacement of 5% RHA, the water absorption slightly increased to 2.3%, but still less than the requirement of 3.5%. The corresponding test results for water suction by capillarity, initial and secondary sorptivity coefficients (Si and Ss) were found to be 0.0330mm/√sec. (1.98mm/√hr.) and 7.95×10−4mm/√sec. (0.04mm/√hr.) respectively, all less than 6mm/√hr requirement. This improved performance was attributed to the increased strength and structure of the interfacial transition zone (ITZ) around the RCA. Conclusion: Based on the results of mechanical strength and water transport, characteristics of the new concrete were improved when coarse RCAs were pretreated with 20% pozzolanic concentration containing cement and RHA. The use of a pozzolanic treatment slurry containing 15% cement and 5% RHA to treat coarse RCA can produce concrete with characteristics similar to those of natural concrete aggregates. This study presents a methodological utilization and improvement of RCA wastes for field application.

Survival of off-host Dermacentor albipictus (Acari: Ixodidae) adult females and larvae underwater

The winter tick ( Dermacentor albipictus (Packard, 1869); Acari: Ixodidae) significantly affects the health and productivity of North American moose ( Alces alces (Linnaeus, 1758); Artiodactyla: Cervidae). Survival of off-host stages of Ixodid ticks depends on microclimate driven in part by extrinsic factors resulting from weather, such as temperature, humidity, drought, and floods. The impact of some of these abiotic factors is unclear for D. albipictus. The effect of water submergence on biological parameters of engorged, adult, females, and unfed larvae was assessed in the laboratory. Survival of adult females after submergence for 3 days was 88% with significant effects on their ability to oviposit. After 5 weeks, 63% of larvae (1-month-old) survived submergence in water, whereas survival of larvae (3-month-old) was reduced to 23% after 7 days. The off-host stages of D. albipictus have variable tolerance to periods of submergence that may influence the number of larvae available on the landscape for recruitment to moose in autumn.

Study of stress profile in cement concrete road of expansive soil due to swell pressure

Sprawling soil is very unsuitable aimed at the edifice of cement concrete roads in his region due to swelling pressure created and this type of swelling pressure is treacherous for the life of cement concrete roads. In expansive soil, swelling and shrinking behaviour are responsible for engendering the swell pressure in the soil, in this research efforts are made to find out the swelling performance for stability of cement concrete roads in terms of their constancy at different levels of swell pressure which is prescribed in the IRC guidelines. The present research paper deals with the evaluation of swell pressure at altered conditions, Ansys software is used to find out the effect of different values of swell pressure created in the soil and their wellbeing. In the rainy season or submergence in water, cement concrete roads and when these roads are constructed in expansive soil this road will be damaged due to failure of subgrade and subgrade soil.

Strength Properties of Full-Size Oriented Strand Board Panels Following Submergence in Potable and Salt Water

Abstract One of the largest contributors to the economic loss from floods is the complete or partial destruction of residential buildings, and finding ways to eliminate or minimize this loss is important. Oriented strand board (OSB) is a wood product commonly used in home construction, so a better understanding of how flood water affects its mechanical properties is warranted. In this study, the moduli of elasticity and rupture (MOE and MOR, respectively) of representative samples removed from full-size (4 by 8-ft [1.2 by 2.4 m]) OSB panels were examined following the submergence of the panels in potable and salt water (surrogates for flood water) for increasing periods of time (i.e., 8, 24, 48, 72, 168, and 336 h). The results of our study show that after 8 hours of panel submersion in potable water, MOR and MOE is reduced by 15 percent and 16 percent, respectively; no significant change was observed in MOR and MOE for panels soaked in salt water. After 168 hours, the MOR loss was 43 percent for panels soaked in potable water and 38 percent for panels soaked in salt water. For MOE, there was a 35 percent loss regardless of water type. Submersion of panels in either water type for an additional 168 hours resulted in no significant change in MOR or MOE. The MOR and MOE of samples removed from the edges of the submerged panels, for both water types, were lower than those of the interior samples. Finally, the decreases in average MOR and MOE following submergence in either water type were approximately independent of brand.

Survival of diapausing females of two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) submerged in water

ABSTRACT Two-spotted spider mite, Tetranychus urticae Koch, is a ubiquitous and highly polyphagous plant pest with a worldwide distribution. Diapause is essential for its survival in the areas with unfavourable seasonal conditions. We investigated whether female mites overwintering close to the soil surface may be adapted to seasonal flooding. Among the tested mites diapausing on leaf surfaces, 76.3 ± 13.1% (mean ± SE) survived submergence in water for 10 days, 4.8 ± 3.0% – for 20–24 days, 3.0 ± 2.1% – for 30 days, and 8.7 ± 5.9% – for 42–46 days. Among the tested mites diapausing inside wheat straws, 33.3 ± 9.0% remained alive after being flooded for ten days, but none survived being submerged for 30 days. Seasonal floodwaters may be an important factor in spider mite dispersal, geographic isolation, and gene flow. Flooding may also be partially responsible for the formation of species assemblages along rivers.

Elemental localisation and a reduced glutathione redox state protect seeds of the halophyte Suaeda maritima from salinity during over-wintering and germination

Saltmarshes are increasingly at risk from sea level rise through climate change. Their vegetation is comprised of halophytes, salt-tolerant plants, that naturally regenerate from seed, yet the combination of functional traits associated with salinity tolerance in seeds is still poorly characterised. Combining approaches in scanning electron microscopy, energy-dispersive spectrometry, biochemistry and physiology, we focussed on elucidating two mechanisms that are commonly utilised by adult halophyte plants: (1) ion accumulation and elemental localisation, and (2) enhanced antioxidant capacity to protect against oxidative stress, in seeds of the saltmarsh halophyte Suaeda maritima during over-wintering and germination.Freshly collected seeds were dormant, and required 19 weeks of submergence in artificial sea water (ASW) at 5 °C, mimicking over-wintering in the field, to release dormancy. Fresh and pre-treated seeds had an abundance of Na+ and Cl−, as well as the reactive oxygen species H2O2 and glutathione disulphide (i.e., oxidised glutathione). This was accompanied by a large pool of reduced glutathione and the low molecular weight thiols cysteine, cysteinyl-glycine and γ-glutamyl-cysteinyl, suggesting a potentiated antioxidant system in preparation for germination. During germination in ASW, the glutathione and thiol redox state was highly reduced, with no consistent production of H2O2. Na and Cl localised in the seed testa and tegmen, while Mg and K were concentrated in the embryo, and Ca and S had a broad distribution across the seed. Small differences in seed moisture content, measured to indicate the extent of osmotic adjustment, did not account for a higher maximum threshold to germination of 2.22 times the concentration of ASW compared to 1.76 times ASW-equivalents for iso-osmotic solutions of polyethylene glycol (PEG). Moreover, the halotime constant (θHalo) was higher (i.e., slower germination) in the presence of ASW than PEG, suggesting that slower germination may give more time to initiate tolerance mechanisms in response to salinity that promote germination. Seeds of S. maritima appear to utilise seawater ions to their benefit during germination in salinity, using elemental localisation to protect the embryo from potential toxicity of Na and Cl, while maintaining a highly reduced cellular redox state.

FRP-concrete bond performance under accelerated hygrothermal conditions

Drawing on information obtained via double lap shear tests, this paper discusses FRP-concrete bond behavior following five weeks of exposure to several accelerated hygrothermal conditions. Material tests were also carried out for both dry carbon fibers and the epoxy used in the bond study under similar hygrothermal conditions. The bond-slip relationship for the hygrothermal conditions were developed, and fracture energy calculated for the FRP-concrete bond. The use of degraded material properties obtained from material test coupons under the same exposure conditions prevented overestimation of the FRP-concrete bond fracture energy. Testing revealed that the FRP-concrete bond strength increased as temperature increased at low humidity (dry heat) — a potential consequence of alteration in the epoxy glass transition temperature. The bond strength of concrete with steel slag incorporated was superior at all temperatures and low humidity. In response to continuous or periodic submergence in water, specimen failure mode transitioned from substrate failure to adhesive-concrete interface failure. Alternating two-day wet/dry cycles resulted in a 12% drop of FRP-concrete bond strength. Under low humidity, the FRP dry fiber tensile stress increased as temperature increased (dry heat), while the opposite dynamic was observed in the epoxy coupons.

Botanical Pharmacognosy of Bacopa monnieri (Linn.) Pennell

Backgound: B. monnieri (Linn.) Pennell is a slender, creeping and mat forming herb well adapted to grow in both terrestrial and submersed conditions. It is an important medicinal plant belongs to the family Plantaginaceae and espoused as a source for the Ayurvedic drug brahmi. Objectives: The present study aims to delineate the morphological and histomorpho diagnostic profile of the stem, root and leaves of brahmi and analyze their qualitative and quantitative anatomical peculiarities to support the pharmacobotanical characterizations using digital, stereo and polarized microscopic techniques. Results: Cross section of lamina had shown a homogeneous mesophyll fails to differentiate into palisade and spongy tissues. Lamina was amphistomatic which contained three different types of stomatal complexes vz., diacytic, anisocytic and anomoteracytic. The mean number of stoma per square millimeter of leaf area was found to be higher in adaxial surface (656.9/mm2) than abaxial (433.3/mm2) with a corresponding stomatal index of 15.2 and 9.4 respectively. Adventitious root in cross section gave ‘spokes in a wheel’ appearance and shoot cortex architecture had shown honey-comb pattern of aerenchyma chambers. Vascular bundles were many, conjoint and closed, where a centra solid core of xylem encircled by phloem. Crystal ideoblasts of calcium oxalate were observed in characteristic tissues of epidermis of the leaves, mesophyll, cortical tissues of stem, and intervening walls of the file of cells of diaphragms in stem and adventitious roots. Conclusion: The above delineated anatomical characteristics in conjunction with aerenchyma in root and shoot tissues as an effective water tolerance mechanism to thrive prolonged submergence in water logged conditions could provide valuable tags as useful markers for pharmacological identification of the taxon.

Seedling Submergence Tolerances Accurately Predict Riparian Tree Species Distributions: Insights to Help Design Environmental Flows

Quantification of flooding thresholds that govern species distributions on microtopographic gradients in floodplains can help design environmental flows, but the multiple correlated dimensions of flooding such as frequency, depth, duration, and timing are a challenge. We postulated that species distributions are limited by the most stressful combination of flooding dimensions when the plants are in their most susceptible developmental stage. To test this idea, we measured survival of young seedlings in pots subjected to flood treatments that completely submerged the seedlings in stagnant water with and without suspended sediments for durations of up to 6 weeks during the growing season. This measure of flood tolerance predicted floodplain distributional limits of 16 tree species with high accuracy (adj. r2 = 0.91). The strength of the result suggests that seedling ability to survive complete submergence in stagnant water for prolonged periods is an important mechanism limiting species distributions in riparian forests. We propose that environmental flows that completely submerge the seedling layer in floodplain forest with stagnant water for at least 3 weeks are likely to be more effective at eliminating invading upland species than flows that only flood the soil up to the root collars of seedlings.

Eco-Physiological Traits Related to Recovery from Complete Submergence in the Model Legume Lotus japonicus.

Submergence is a severe form of stress for most plants. Lotus japonicus is a model legume with potential use in assisting breeding programs of closely related forage Lotus species. Twelve L. japonicus genotypes (10 recombinant inbred lines (RILs) and 2 parental accessions) with different constitutive shoot to root dry mass ratios (S:R) were subjected to 7 days of submergence in clear water and allowed to recover for two weeks post-submergence; a set of non-submerged plants served as controls. Relative growth rate (RGR) was used to indicate the recovery ability of the plants. Leaf relative water content (RWC), stomatal conductance (gs), greenness of basal and apical leaves, and chlorophyll fluorescence (Fv/Fm, as a measure of photoinhibition) were monitored during recovery, and relationships among these variables and RGR were explored across genotypes. The main results showed (i) variation in recovery ability (RGR) from short-term complete submergence among genotypes, (ii) a trade-off between growth during vs. after the stress indicated by a negative correlation between RGR during submergence and RGR post-submergence, (iii) an inverse relationship between RGR during recovery and S:R upon de-submergence, (iv) positive relationships between RGR at early recovery and RWC and gs, which were negatively related to S:R, suggesting this parameter as a good estimator of plant water balance post-submergence, (v) chlorophyll retention allowed fast recovery as revealed by the positive relationship between greenness of basal and apical leaves and RGR during the first recovery week, and (vi) full repair of the submergence-damaged photosynthetic apparatus occurred more slowly (second recovery week) than full recovery of plant water relations. The inclusion of these traits contributing to submergence recovery in L. japonicus should be considered to speed up the breeding process of the closely related forage Lotus spp. used in current agriculture.

Surviving the Antarctic winter-Life Stage Cold Tolerance and Ice Entrapment Survival in The Invasive Chironomid Midge Eretmoptera murphyi.

An insect’s ability to tolerate winter conditions is a critical determinant of its success. This is true for both native and invasive species, and especially so in harsh polar environments. The midge Eretmoptera murphyi (Diptera, Chironomidae) is invasive to maritime Antarctic Signy Island, and the ability of fourth instar larvae to tolerate freezing is hypothesized to allow the species to extend its range further south. However, no detailed assessment of stress tolerance in any other life stage has yet been conducted. Here, we report that, although larvae, pupae and adults all have supercooling points (SCPs) of around −5 °C, only the larvae are freeze-tolerant, and that cold-hardiness increases with larval maturity. Eggs are freeze-avoiding and have an SCP of around −17 °C. At −3.34 °C, the CTmin activity thresholds of adults are close to their SCP of −5 °C, and they are likely chill-susceptible. Larvae could not withstand the anoxic conditions of ice entrapment or submergence in water beyond 28 d. The data obtained here indicate that the cold-tolerance characteristics of this invasive midge would permit it to colonize areas further south, including much of the western coast of the Antarctic Peninsula.

Pore system characteristics of soil aggregates and their relevance to aggregate stability

Aggregates are the structural units of soils, and the physical stability is considered to be a keystone parameter of soil quality. However, little is known about the evolution of the pore system in aggregates and its importance in defining aggregate stability. In this paper, we investigated the pore system and stability of three dominant macroaggregate sizes (1–2, 2–5 5–10 mm) obtained from a fine sand-loamy Chernozem under three distinct land uses (arable, grassland and forest). We used non-invasive X-ray microtomography (XMT) in combination with pore network extraction to characterise PSD (pore size distribution) of aggregates and their potential changes upon continued submergence in water. We showed that smaller aggregates (1–2 mm) have significantly higher total X-ray resolvable porosity than the medium (2–5 mm) and large (5–10 mm) aggregates. Also, using imaging tools, we demonstrated for the first time, that the pore system of stable aggregates from grassland and forest does not undergo significant changes upon continued submergence in water. It can be hypothesised that a physically stable pore structure allows the storage and transmission of water without a structural collapse, thereby contributing to aggregate stability. We found statistically significant positive correlations between different pore groups (closed pores, water holding pores and air space spores) and water stability of aggregates from all three land uses suggesting that pore system characteristics play a significant role in aggregate stability. Our results suggest that PSD is an important factor that determines the stability of soil aggregates.

Seed Longevity of Spotted Spurge and Wild Poinsettia Under Diverse Environmental Conditions

ABSTRACT: Seed longevity under different environmental conditions is considered as one of the most important factors in the spread and persistence of an exotic species. The Experiments were conducted to determine seed persistence in soil, effects of submergence in water, flooding of the soil, and high temperatures on germination and viability of spotted spurge (Chamaesyce maculata) and wild poinsettia (Euphorbia heterophylla) as two exotic species in different regions of Golestan province. Spotted spurge seeds buried at depth of 10 cm maintained their viability above 95% after a year, while wild poinsettia seeds were destroyed completely after exhuming the soil. Seeds of both species were unable to germinate under submergence, but 92% of the spotted spurge seeds remained viable under this condition for 14 d. No germination was observed after 9 weeks submersion. Submersion duration drastically affected seed germination of wild poinsettia, so that no germination occurred after 6 d submersion. Twelve days after flooding, spotted spurge emergence decreased by 57% compared to the control. Ten percentage of wild poinsettia seedlings emerged when flooding was kept up to 12 d after sowing, while control had 96% emergence. Germination of spotted spurge seeds subjected to 140 oC for 5 min was 5%. Viability of wild poinsettia seed was completely lost at 120 and 140 C for 5 min. These results suggest that spotted spurge is capable of forming persistent seedbank. Seeds of spotted spurge were partially tolerant to submersion in water, but wild poinsettia seed are susceptible to submergence. The burning of crop residue could also prevent augmenting the soil seed bank of both species.

Effects of short term submergence in salt water on water absorption and germination of Pinus thunbergii Parl. seed

Effects of short term submergence in salt water on water absorption and germination of <i>Pinus thunbergii</i> Parl. seed

Effects of short term submergence in salt water on seed germination and sprouting of &lt;i&gt;Pinus thunbergii &lt;/i&gt;Parl.

Effects of short term submergence in salt water on seed germination and sprouting of &lt;i&gt;Pinus thunbergii &lt;/i&gt;Parl.

Recovery from short-term complete submergence in temperate pasture grasses

The ability to recover from the impact of short-term submergence was assessed on four widely used grasses in pastures: Dactylis glomerata L., Bromus catharticus Vahl., Schedonorus arundinaceus Schreb. (syn. Festuca arundinacea) and Phalaris aquatica L. Six-week-old plants were subjected to a 5-day complete submergence in clear water, followed by a 15-day recovery period. Dry mass after submergence, shoot and root growth, number of tillers per plant, leaf stomatal conductance and leaf greenness during recovery were assessed. Dactylis glomerata and B. catharticus were sensitive to submergence, showing very low relative growth rate (RGR) of shoots and roots during recovery (37–67% lower than controls) along with early leaf senescence and persistent partial stomatal closure. Schedonorus arundinaceus exhibited an intermediate tolerance, sustaining high RGR of shoots (similar to controls) and fully adjusting its leaf functionality during recovery despite being affected during submergence (40% decrease in dry mass and 37% in tiller number). Phalaris aquatica performed outstandingly, with dry mass unaffected by submergence, and unaltered stomatal conductance, leaf greenness, tillering and shoot growth during recovery. Therefore, in areas where flooding can often cause plant submergence, P. aquatica is recommended whereas the other species are not, because they may be outcompeted by flood-tolerant species.

Cox proportional hazards modelling of blockage risk in vitrified clay wastewater pipes

Older wastewater systems often contain vitrified clay pipes and these pipes are responsible for a significant proportion of blockages. From previous research and site experience, it is known that age, installation period, pipe length, diameter, depth and joint type affect the risk of blockage. Using statistical analysis we extend this list of variables to include soil type, road/rail proximity and road type. The analysis is based on blockage data for 43,976 vitrified clay pipes over a 7 year period. A Cox proportional hazards modelling (PHM) approach using established and new explanatory variables finds that pipe depth, pipe length, pipe gradient, pipe diameter, submergence in water, joint type, pipe installation decade, soil type, road proximity to the pipe, pipe purpose, land use code and road type are associated with risk of blockage. Pipes with the highest risk of failure due to blockage are identified and their locations and risk level are visually represented on a colour coded map. This analysis approach can be used by asset managers working in cost-constrained environments to appropriately target inspection, plan maintenance and replacement programs.

Retain or repel? Droplet volume does matter when measuring leaf wetness traits.

Leaf wetness is an important characteristic linked to a plant's strategies for water acquisition, use and redistribution. A trade-off between leaf water retention (LWR) and hydrophobicity (LWH) may be expected, since a higher LWH/lower LWR may enhance photosynthesis, while the opposite combination may increase the leaf water uptake (LWU). However, the validation of the ecological meaning of both traits and the influence of droplet volume when measuring them have been largely neglected. To address these questions, LWR and LWH of 14 species were measured using droplets of between 5 and 50 μL. Furthermore, the ability of those species to perform LWU was evaluated through leaf submergence in water. The droplet-volume effect on absolute values and on species ranking for LWR and LWH was tested, as well as the influence of water droplet volume on the relationship between leaf wetness traits and LWU. Variations in droplet volume significantly affected the absolute values and the species ranking for both LWR and LWH. The expected negative correlation between leaf wetness traits was not observed, and they were not validated as a proxy for LWU. The water droplet volume does matter when measuring leaf wetness traits. Therefore, it is necessary to standardize the methodological approach used to measure them. The use of a standard 5 μL droplet for LWH and a 50 μL droplet for LWR is proposed. It is cautioned that the validation of both traits is also needed before using them as proxies to describe responses and effects in functional approaches.