The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Daniel Beysens - One of the best experts on this subject based on the ideXlab platform.
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foliar uptake of Dew in the sandy ecosystem of the mongolia plateau a life sustaining and carbon accumulation strategy shared differently by c3 and c4 grasses
Agricultural and Forest Meteorology, 2020Co-Authors: Meizhen Liu, Yu Cen, Chengdong Wang, Peter A Bowler, Lin Zhang, Gaoming Jiang, Daniel BeysensAbstract:Abstract Dew is an important source of available water in arid or semi-arid areas and considerable attention has focused upon whether foliar Dew uptake occurs. Nonetheless, its occurrence and effects on plant growth in the sand-based ecosystems of the Mongolia Plateau are largely unknown. We performed laboratory experiments and conducted a three-year field investigation of Dew in the Hunshandak sandland, northern China. Dew yield was determined by a weighing method. The ecological significance of Dew was evaluated by measuring isotopes in the field, leaf water content, photosynthesis and the biomass of drought-stressed plants exposed to Dew. Nights producing Dew comprised 53% of those between June and October when the atmospheric relative humidity was higher than 80% and wind speed was lower than 4.0 m s−1. Dew yield averaged 0.15 mm night−1 and its maximum value was 0.30 mm night−1. When exposed to Dew, drought-stressed plants increased leaf relative water content and net photosynthetic rate (Pn) between 5-76% and 5-240% for C3 plants, and 3–18% and 5–109% for C4 plants. Dew produced more root and total biomass (15–81% and 24–82%) in C4 species than in C3 species (3–28% and 5–25%). Regular Dew events on five or more consecutive nights in seven days can sustain C3 species, while C4 species accumulate more carbon resources. This study found that the high Dew yield in arenicolous ecosystems was due to the soil matrix and environmental differences in the neighboring steppe ecosystem. C4 species and drought resistant C3 species displayed higher efficiency for Dew utilization than the moderately drought resistant C3 species. This may affect the plant community's dynamic and ecological interactions in response to future climate change.
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Grooves Accelerate Dew Shedding
Physical Review Letters, 2019Co-Authors: Pierre-brice Bintein, Henri Lhuissier, Anne Mongruel, Laurent Royon, Daniel BeysensAbstract:Gravity-driven drainage of small volumes of condensates, such as natural Dew, is a challenge because small drops usually remain pinned to inclined surfaces. We report that submillimetric grooves substantially reduce Dew retention by modifying the repartition of liquid: Because of a long-range coalescence mechanism mediated by grooves imbibition, the growth and shedding of large drops are accelerated. Such findings can be applied to increase the passive harvesting of Dew as well as to accelerate the drainage of other condensates.
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estimating Dew yield worldwide from a few meteo data
Atmospheric Research, 2016Co-Authors: Daniel BeysensAbstract:Abstract There is a general need to determine Dew yield in any place of the world. However, its determination requires systematic measurements that are not available everywhere. In addition, it depends on the particularities of the Dew collector. A simple analytical formula valid for planar Dew collectors is elaborated here. It is based on laboratory experiments where it is established that heat loss with surrounding air is the dominant parameter that limits Dew condensation. A simple analytical formulation is then derived, which only needs cloud coverage, wind velocity, air and Dew point temperature data to be collected, at least once in a day before sunrise. The formulation is tested in several places in the world with different climates. Agreement within typically 30% is found with Dew measurements. Such an analytical relationship can thus provide a useful tool to obtain a worldwide estimation of the Dew potential.
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Dew as a sustainable non conventional water resource a critical review
Environmental Reviews, 2015Co-Authors: M Tomaszkiewicz, Daniel Beysens, Majdi Abou Najm, Ibrahim Alameddine, M ElfadelAbstract:Over the last 20 years, Dew harvesting has evolved to fruition because of a better understanding of its physics, thermodynamics, and the radiative cooling process of condensing substrates. Although resultant yields are relatively small, Dew positions itself as a viable water resources supplement because it occurs naturally and frequently in many locations globally, particularly in the absence of precipitation or when more traditional water sources are subject to depletion. Moreover, Dew water is generally potable, especially in rural locations, where it is most beneficial. This review summarizes Dew harvesting research achievements to date including formation processes, collection in various environments, prediction models, water quality, and applications. The paper concludes with outlining existing gaps and future research needs to improve the understanding and performance of Dew harvesting in the context of adaptation to climate change.
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Dew fog and rain as supplementary sources of water in south western morocco
Energy, 2011Co-Authors: Imad Lekouch, Marc Muselli, Belkacem Kabbachi, Jalil Ouazzani, Iryna Melnytchoukmilimouk, Daniel BeysensAbstract:One full year of Dew, fog and rain collection measurements data were collected during 2007–2008 of in the dryland area of Mirleft, Morocco, for use as alternative or supplemental sources of water. Four passive Dew condensers and a passive fog net collector were used, each with 1m2 surfaces. Meteorological data were collected in parallel. During the observation period, 178 Dew events (18.85mm), 31 rain events (48.65mm) and 7 significant fog episodes (1.41mm) occurred, corresponding to almost 40% of the yearly rain contribution (48.7mm, 31 events). Chemical and biological analyses were carried out. Dew and rain pH were neutral (close to 7) and the total mineralization was considerable (Dew: 560mg/L; rain: 230mg/L). Ca2+, K+, SO42− and NO3− were of continental origin; Cl−, Na+ and Mg2+ were of sea origin. The ions concentration agrees with the World Health Organization recommendations for potable water. The biological analysis shows harmless vegetal spores and little contamination by animal/human bacteria. A cost analysis shows that, with little investment, the population of the arid and semi-arid coastal areas of south-western north Africa could make Dew water a useful supplementary alternative water resource.
Kelly K. Caylor - One of the best experts on this subject based on the ideXlab platform.
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Dew deposition suppresses transpiration and carbon uptake in leaves
Agricultural and Forest Meteorology, 2018Co-Authors: Cynthia Gerleinsafdi, Kelly K. Caylor, Michael C Koohafkan, Michaella Chung, Fulton E Rockwell, Sally E ThompsonAbstract:Abstract Dew deposition occurs in ecosystems worldwide, even in the driest deserts and in times of drought. Although some species absorb Dew water directly via foliar uptake, a ubiquitous effect of Dew on plant water balance is the interference of Dew droplets with the leaf energy balance, which increases leaf albedo and emissivity and decreases leaf temperature through Dew evaporation. Dew deposition frequency and amount are expected to be affected by changing environmental conditions, with unknown consequences for plant water stress and ecosystem carbon, water and energy fluxes. Here we present a simple leaf energy balance that characterizes the effect of deposition and the evaporation of Dew on leaf energy balance, transpiration, and carbon uptake. The model is driven by five common meteorological variables and shows very good agreement with leaf wetness sensor data from the Blue Oak Ranch Reserve in California. We explore the tradeoffs between energy, water, and carbon balances for leaves of different sizes across a range of relative humidity, wind speed, and air temperature conditions. Our results show significant water savings from transpiration suppression up to 25% for leaf characteristic lengths of 50 cm. CO 2 assimilation is decreased by up to 12% by the presence of Dew, except for bigger leaves in windspeed conditions below 1 m s −1 when an increase in assimilation is expected.
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Dew-induced transpiration suppression impacts the water and isotope balances of Colocasia leaves
Oecologia, 2018Co-Authors: Cynthia Gerlein-safdi, Paul P. G. Gauthier, Kelly K. CaylorAbstract:Foliar uptake of water from the surface of leaves is common when rainfall is scarce and non-meteoric water such as Dew or fog is more abundant. However, many species in more mesic environments have hydrophobic leaves that do not allow the plant to uptake water. Unlike foliar uptake, all species can benefit from Dew- or fog-induced transpiration suppression, but despite its ubiquity, transpiration suppression has so far never been quantified. Here, we investigate the effect of Dew-induced transpiration suppression on the water balance and the isotope composition of leaves via a series of experiments. Characteristically, hydrophobic leaves of a tropical plant, Colocasia esculenta , are misted with isotopically enriched water to reproduce Dew deposition. This species does not uptake water from the surface of its leaves. We measure leaf water isotopes and water potential and find that misted leaves exhibit a higher water potential and a more depleted water isotope composition than dry leaves, suggesting a ∼ 30% decrease in transpiration rate compared to control leaves. We propose three possible mechanisms governing the interaction of water droplets with leaf energy balance: increase in albedo from the presence of Dew droplets, decrease in leaf temperature from the evaporation of Dew, and local decrease in vapor pressure deficit. Comparing previous studies on foliar uptake to our results, we conclude that transpiration suppression has an effect of similar amplitude, yet opposite sign to foliar uptake on leaf water isotopes.
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Dew induced transpiration suppression impacts the water and isotope balances of colocasia leaves
bioRxiv, 2018Co-Authors: Cynthia Gerleinsafdi, Paul P. G. Gauthier, Kelly K. CaylorAbstract:Foliar uptake of water from the surface of leaves is common when rainfall is scarce and non-meteoric water such as Dew or fog is more abundant. However, many species in more mesic environments have hydrophobic leaves that do not allow the plant to uptake water. Unlike foliar uptake, all species can benefit from Dew- or fog-induced transpiration suppression, but despite its ubiquity, transpiration suppression has so far never been quantified. Here, we investigate the effect of Dew-induced transpiration suppression on the water balance and the isotopic composition of leaves via a series of experiments. Characteristically hydrophobic leaves of a tropical plant, Colocasia esculenta , are misted with isotopically enriched water to reproduce Dew deposition. We measure leaf water isotopes and water potential and find that misted leaves exhibit a higher water potential (p
Marc Muselli - One of the best experts on this subject based on the ideXlab platform.
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Dew fog and rain water collectors in a village of s morocco idouasskssou
Desalination and Water Treatment, 2013Co-Authors: O Clus, Marc Muselli, Imad Lekouch, Iryna Milimoukmelnytchouk, D. BeysensAbstract:Abstract The coastal region of south Morocco presents a chronically shortage of drinkable and fresh water. In 2007, only 49 mm of rain was recorded. However, measurements in the same year showed that the Dew yield was on order of 40% of rain fall. In order to recover Dew water in addition to rain water, a small village (Idouasskssou), 8 km from Mirleft and the Atlantic Ocean, was equipped with three pilot condensers of 136 m2 total surface area. A local organization (IMIRJANE) collaborated to ensure a good integration of the project by the village inhabitants. All materials were from local shops. Only the special radiative and hydrophilic coating was coming from non local resources (www.opur.fr). Dew water production during six months, from 15 December. 2008 to 31 July. 2009 (137 Dew events, 47% of days) was more than 3,800 L (28 mm, 0.2 mm/Dew day). The devices not only condense Dew water, they also harvest rain and fog, thus providing to the population a valuable water resource (during fall 2009, the co...
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Dew fog and rain as supplementary sources of water in south western morocco
Energy, 2011Co-Authors: Imad Lekouch, Marc Muselli, Belkacem Kabbachi, Jalil Ouazzani, Iryna Melnytchoukmilimouk, Daniel BeysensAbstract:One full year of Dew, fog and rain collection measurements data were collected during 2007–2008 of in the dryland area of Mirleft, Morocco, for use as alternative or supplemental sources of water. Four passive Dew condensers and a passive fog net collector were used, each with 1m2 surfaces. Meteorological data were collected in parallel. During the observation period, 178 Dew events (18.85mm), 31 rain events (48.65mm) and 7 significant fog episodes (1.41mm) occurred, corresponding to almost 40% of the yearly rain contribution (48.7mm, 31 events). Chemical and biological analyses were carried out. Dew and rain pH were neutral (close to 7) and the total mineralization was considerable (Dew: 560mg/L; rain: 230mg/L). Ca2+, K+, SO42− and NO3− were of continental origin; Cl−, Na+ and Mg2+ were of sea origin. The ions concentration agrees with the World Health Organization recommendations for potable water. The biological analysis shows harmless vegetal spores and little contamination by animal/human bacteria. A cost analysis shows that, with little investment, the population of the arid and semi-arid coastal areas of south-western north Africa could make Dew water a useful supplementary alternative water resource.
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Dew, fog, and rain as supplementary sources of water in south-western Morocco
Energy, 2011Co-Authors: I. Lekouch, Marc Muselli, Belkacem Kabbachi, Jalil Ouazzani, Iryna Melnytchouk-milimouk, Daniel BeysensAbstract:This study reports on one year (May 1, 2007 - April 30, 2008) of Dew, fog and rain measurements carried out in the dryland area of Mirleft, Morocco in order to be used as alternative or supplemental sources of water. Four standard Dew condensers and a passive fog net collector of 1 m² surfaces were used. Meteorological data were collected. 178 Dew events (18.85 mm), 31 rain events (48.65 mm) and 7 significant fog episodes (1.41 mm) occurred, corresponding to almost 40% of the yearly rain contribution (48.65 mm, 31 events). Chemical and biological analyses were carried out. Dew and rain pH were neutral (close to 7) and the total mineralization was considerable (Dew: 560 mg/L; rain: 230 mg/L). Ca²+, K+, SO42- and NO3- are found of continental origin; Cl-, Na+ and Mg2+ are of sea origin. The ions concentration agrees with the World Health Organization recommendations for potable water. The biological analysis shows harmless vegetal spores and little contamination by animal/human bacteria. A cost analysis shows that, with little investment, the population of the arid and semi-arid coastal areas of south-western north Africa could make Dew water an interesting supplementary alternative water resource.
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chemical and biological characteristics of Dew and rain water in an urban coastal area bordeaux france
Atmospheric Environment, 2006Co-Authors: Daniel Beysens, Catherine Ohayon, Marc Muselli, O ClusAbstract:Abstract We report on a 1-year investigation (15 January 2002–14 January 2003) in Bordeaux, France, comparing the quality of Dew water with respect to rain water. The following physico-chemical and bacteriological properties of Dew and rain water were measured: pH, electric conductivity, cations (Na+, K+, Ca2+, Mg++, Zn++, Cu++), anions (Cl−, SO42−, NO3−, NO2−), hardness (TH, calcical, magnesial, permanent), complete alkalimetric title, dry residue and number of colony-forming unities (CFU) at 22 and 36 °C. The CO32−, HCO3−, HPO42− concentrations were found negligible. The ionic concentrations are in general lower in Dew than in rain with NO2− as a noticeable exception. The mean rain pH (5.4) is lower than Dew pH (6.3). The major ions are from the nearby Atlantic Ocean (within 50 km). Average ion concentrations are found below the World Health Organization (WHO) limit requirements for potable water; Dew composition is close to low mineralized commercial spring waters for the analyzed ions. The biological analyses are concerned with CFU at 22 and 36 °C. Dew is seen to exceed on various occasions the WHO limits.
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Dew water collector for potable water in Ajaccio (Corsica Island, France)
Atmospheric Research, 2002Co-Authors: Marc Muselli, Daniel Beysens, Jacques Marcillat, Iryna Milimouk, Torbjörn Nilsson, Alain LoucheAbstract:We report on the development of an inexpensive radiative condenser for collecting atmospheric vapor. Based on the experience gained using a small working model in Grenoble (France), a prototype of 10×3 m2 was established in Ajaccio (Corsica, France). The condensing surface is a rectangular foil made of TiO2 and BaSO4 microspheres embedded in polyethylene and has an angle of 30° with respect to horizontal. The hollow part of the device, thermally isolated, faces the direction of the dominant nocturnal wind. Dew measurements were correlated with meteorological data and compared to Dew condensed on a horizontal polymethylmethacrylate (PMMA, Plexiglas) reference plate. The plate served as a reference standard unit and was located nearby. Between July 22, 2000 and November 11, 2001 (478 days), there were 145 Dew days for the reference plate (30%), but 214 Dew days for the condenser (45%). This yield corresponds to 767 l (3.6 l, on average, per Dew day). The maximum yield in the period was 11.4 l/day. Dew mass can be fitted to a simple model that predicts Dew production from simple meteorological data (temperature, humidity, wind velocity, cloud cover). Chemical analyses of the water collected from the plate were performed from October 16, 1999 to July 16, 2000 and from the condenser, from July 17, 2000 to March 17, 2001. The following parameters were investigated: suspended solids, pH, concentration of SO42−, Cl−, K+, Ca2+ ions. Only Cl− and SO42− ions were sometimes found significant. Wind direction analyses revealed that Cl− is due to the sea spray and SO42− to the combustion of fuel by an electrical plant located in the Ajaccio Gulf. Except for a weak acidity (average pH≈6) and high concentration of suspended solids, Dew water fits the requirements for potable water in France with reference to the above ions.
I Wang - One of the best experts on this subject based on the ideXlab platform.
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development of a Dew frost point temperature sensor based on tunable diode laser absorption spectroscopy and its application in a cryogenic wind tunnel
Sensors, 2018Co-Authors: Wei Nie, Lu Yao, Ju Rua, I WangAbstract:We have proposed a sensor for real-time and online measurement of Dew/frost point temperature using tunable diode laser absorption spectroscopy (TDLAS) technique. Initial experiments have demonstrated its feasibility and technical advantages in comparison to a chilled mirror hygrometer (CMH). The TDLAS sensor we developed has a Dew/frost point temperature range from -93 °C to + 14.5 °C, with a measurement uncertainly of less than 2%, and a response time of about 0.8 s, which is much faster than that of the chilled mirror hygrometer (ranging from several minutes to several hours). A TDLAS-based Dew/frost point sensor has many advantages, such as rapid and continuous measurements, low frost point temperature sensing, high accuracy, and non-intrusiveness. Such a sensor would be useful for Dew/frost point temperature determinations in various applications. In a cryogenic wind tunnel, real-time Dew/frost point temperature measurements are helpful in preventing the formation of condensed liquid and ice, which can affect the model geometry and lead to unreliable test data.
Wei Nie - One of the best experts on this subject based on the ideXlab platform.
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development of a Dew frost point temperature sensor based on tunable diode laser absorption spectroscopy and its application in a cryogenic wind tunnel
Sensors, 2018Co-Authors: Wei Nie, Lu Yao, Ju Rua, I WangAbstract:We have proposed a sensor for real-time and online measurement of Dew/frost point temperature using tunable diode laser absorption spectroscopy (TDLAS) technique. Initial experiments have demonstrated its feasibility and technical advantages in comparison to a chilled mirror hygrometer (CMH). The TDLAS sensor we developed has a Dew/frost point temperature range from -93 °C to + 14.5 °C, with a measurement uncertainly of less than 2%, and a response time of about 0.8 s, which is much faster than that of the chilled mirror hygrometer (ranging from several minutes to several hours). A TDLAS-based Dew/frost point sensor has many advantages, such as rapid and continuous measurements, low frost point temperature sensing, high accuracy, and non-intrusiveness. Such a sensor would be useful for Dew/frost point temperature determinations in various applications. In a cryogenic wind tunnel, real-time Dew/frost point temperature measurements are helpful in preventing the formation of condensed liquid and ice, which can affect the model geometry and lead to unreliable test data.
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Development of a Dew/Frost Point Temperature Sensor Based on Tunable Diode Laser Absorption Spectroscopy and Its Application in a Cryogenic Wind Tunnel
MDPI AG, 2018Co-Authors: Wei Nie, Ruifeng Kan, Jun Ruan, Lu Yao, Bin WangAbstract:We have proposed a sensor for real-time and online measurement of Dew/frost point temperature using tunable diode laser absorption spectroscopy (TDLAS) technique. Initial experiments have demonstrated its feasibility and technical advantages in comparison to a chilled mirror hygrometer (CMH). The TDLAS sensor we developed has a Dew/frost point temperature range from −93 °C to + 14.5 °C, with a measurement uncertainly of less than 2%, and a response time of about 0.8 s, which is much faster than that of the chilled mirror hygrometer (ranging from several minutes to several hours). A TDLAS-based Dew/frost point sensor has many advantages, such as rapid and continuous measurements, low frost point temperature sensing, high accuracy, and non-intrusiveness. Such a sensor would be useful for Dew/frost point temperature determinations in various applications. In a cryogenic wind tunnel, real-time Dew/frost point temperature measurements are helpful in preventing the formation of condensed liquid and ice, which can affect the model geometry and lead to unreliable test data