Effect of uniconazole and limited water on growth,water relations,and mineral nutrition of “Lalandei” Pyracantha

Pyracantha (Pyracantha coccinea M. J. Roem. Lalandei) plants were treated with uniconazole at 0.5 mg ai container^–1 as a medium drench, 150 mg ai L^–1 as a foliar spray, or left untreated. Plants from all treatments were placed under three water regimes: drought acclimated, nonacclimated and later exposed to drought, or nonstressed. Acclimated plants were conditioned by seven 4-day stress cycles (water withheld), while nonacclimated were well watered prior to a single 4-day stress cycle at the same time as the seventh drought cycle of acclimated plants. Nonstressed plants were well watered throughout the study. Nonstressed plants had higher leaf water potentials and leaf conductances than acclimated and nonacclimated plants, and transpiration rates were higher in nonacclimated than acclimated plants. Uniconazole did not affect leaf water potential, leaf conductance, or transpiration rate. Acclimated plants had smaller leaf areas and leaf, stem, and root dry weights than nonacclimated or nonstressed plants. Plants drenched with uniconazole had the lowest stem and root dry weights. Acclimated plants also contained higher N concentrations than nonacclimated or nonstressed plants, and higher P concentrations than nonacclimated plants. Uniconazole medium drench treatments increased levels of Mn and P. Calcium concentration was increased in plants receiving either medium drench or foliar applications.     

China’s water footprint by province,and inter-provincial transfer of virtual water

Water shortages and the uneven distribution of water resources restrict China’s sustainable development. The concepts of virtual water and water footprints provide a new approach to alleviate regional shortages of Chinese water resources by the inter-provincial allocation of commercial water resources. In this study, an interregional input-output model was applied to quantitatively estimate the water footprint of each province in China and to quantify the inter-provincial transfer of virtual water. The results indicated that there was considerable diversity in the water footprints of the various provinces. Provinces with larger populations and greater GDP had larger water footprints, and developed regions had higher proportions of external water footprints. From the perspective of final demand, local consumption was the main factor driving the water footprints of these provinces. From the perspective of sectoral structure, the agricultural water footprint had a larger proportion in these provinces. The transfer of virtual water in China did not occur from regions with abundant water resources to those suffering from water shortages, but it generally occurred from west to east, from inland to coastal areas, and from underdeveloped to developed regions. Many water-deficient regions also had large net virtual water exports. Water shortages in China will be alleviated by the enhancement of industrial water-use efficiency in water-deficient regions, the transfer of water-intensive industries to regions with abundant water resources, and the development of tertiary industries with low water consumption.     

Taphonomy of modern deep,cold‐temperate water coral reefs

Deep‐water corals are widely distributed along the cold‐temperate northeastern Atlantic continental margin. Despite the widespread occurrence of these aphotic coral constructions in deep shelf settings, the processes of framework formation and postmortem alterations which result in different preservational styles are still poorly known. Detailed mapping surveys on probably one of the largest Lophelia reef structures were carried out on the Sula Ridge, Mid‐Norwegian Shelf in 270 to 300 m depth. Side scan sonar records and camera surveys yield information at various scales of resolution on the reef complex which is more than 9 km long and up to 45 m high. Living Lophelia colonies effectively prevent colonization by other organisms and are successful in the rejection of passing detrital material from the soft tissue. In a healthy condition the coral is able to encrust repetitively attached organisms by selectively secreted sclerenchyme layers, thus, this defensive reaction results in the thickening of the skeleton. Early postmortem alteration in Lophelia colonies is introduced by the formation of a biofilm and Dodgella (fungi) infestation. The biofilm is associated with selective Fe‐Mn precipitation on the coral skeleton. This is the zone of intense attachment of sessile invertebrates such as serpulids, brachiopods, foraminifers and encrusting bryozoans. More advanced taphonomic stages show an increasing dominance in sponges which reduce the interskeletal framework porosity significantly. In addition, boring sponges excavate the thickly calcified Lophelia skeletons, thus leading to in situ collapsing structures on the sea floor. It is the intensity of sediment trapping biofilms and sponge colonization and the amount of imported detrital particles predominantly from the pelagial zone that control the generation of a pure coral rubble facies or the preservation of collapsed but mud‐rich detrital mounds.     

Phase Behavior, Stability, and Mesomorphism of Monostearin–oil–water Gels

This paper is the characterization of a new material comprised of oil, water, monostearin and stearic acid, which can be used as a heart-friendly, low-saturate, trans fatty acid-free spreadable fat and shortening. Oil–water–monstearin mixtures formed a gel above 2% monostearin and 30% water and were stable over a month’s time. An increase in the storage modulus (G′), and peak melting temperature (T _m) was observed over time, which suggests a slow change in structure to a more solid form. Powder x-ray diffraction measurements at temperatures above the Krafft temperature of the monglyceride (57°C) indicated the existence of a lamellar liquid crystalline phase $ {\left( {L_{\alpha } } \right)} This paper is the characterization of a new material comprised of oil, water, monostearin and stearic acid, which can be used as a heart-friendly, low-saturate, trans fatty acid-free spreadable fat and shortening. Oil–water–monstearin mixtures formed a gel above 2% monostearin and 30% water and were stable over a month’s time. An increase in the storage modulus (G′), and peak melting temperature (T _m) was observed over time, which suggests a slow change in structure to a more solid form. Powder x-ray diffraction measurements at temperatures above the Krafft temperature of the monglyceride (57°C) indicated the existence of a lamellar liquid crystalline phase with a (001) reflection occurring at 50 ?. In addition to the 50 ? reflection at small angles, a wide angle reflection at 4.2 ? was observed upon cooling below 60°C, indicating a transition from the to the phase, which upon storage at 22°C for one day converted to the coagel, or β-gel phase.     

How do salinity and water stress affect transport of water,assimilates and ions to tomato fruits?

The study was conducted in order to determine whether water stress affects the accumulation of dry matter in tomato fruits similarly to salinity, and whether the increase in fruit dry matter content is solely a result of the decrease in water content. Although the rate of water transport to tomato fruits decreased throughout the entire season in saline water irrigated plants, accumulation rates of dry matter increased significantly. Phloem water transport contributed 80–85% of the total water transport in the control and water-stressed plants, and over 90% under salinity. The concentration of organic compounds in the phloem sap was increased by 40% by salinity. The rate of ions transported via the xylem was also significantly increased by salinity, but their contribution to fruit osmotic adjustment was less. The rate of fruit transpiration was also markedly reduced by salinity. Water stress also decreased the rate of water transport to the tomato fruit and increased the rate of dry matter accumulation, but much less than salinity. The similar changes, 10–15%, indicate that the rise in dry matter accumulation was a result of the decrease in water transport. Other parameters such as fruit transpiration rates, phloem and xylem sap concentration, relative transport via phloem and xylem, solutes contributing to osmotic adjustment of fruits and leaves, were only slightly affected by water stress. The smaller response of these parameters to water stress as compared to salinity could not be attributed to milder stress intensity, as leaf water potential was found to be more negative. Measuring fruit growth of girdled trusses, in which phloem flow was inactive, and comparing it with ungirdled trusses validated the mechanistic model. The relative transport of girdled as compared to ungirdled fruits resembled the calculated values of xylem transport.     

Phosphorus concentration in sediment, water and tissues of␣three submerged macrophytes of Myall Lake, Australia

Phosphorus content in sediment, water and tissues of three macrophyte species growing in Myall Lake, Australia were studied from January to November, 2004. The sites investigated were North–West (NW), North–East (NE), South–West (SW) bays and Central deep area of the lake (CL). The objective of this study was to investigate how total phosphorus (TP) in plant tissues relate to phosphorus pools and the role played by the aquatic macrophyte species under investigation in phosphorus recycling in the lake. Of the four investigated sites of the lake, TP in plant tissues were significantly higher in North–West and South–West bays compared to the rest. Najas marina had significantly higher TP content (e.g., 1.55 and 1.44 mg/g dw.; P < 0.05) for NW and SW respectively, than the other two species. N. marina is a rooted macrophyte while charophytes (C. fibrosa and Nitella hyalina) are pseudo-rooted macrophytes. Total phosphorus in the sediment and water column were significantly higher in Central deep area of the lake compared to the other three bays (P < 0.05, n 5). Soluble reactive phosphorus (SRP) and total dissolved phosphorus (TDP) in sediment pore water correlated significantly with phosphorus content in the tissue of N. marina ( ; ) as well as TP in sediment (␣ and ). Using the two-compartmental uptake model, it was observed that, sediment was the main compartment through which Ni. hyalina obtained phosphorus while for the other two species, water column was the uptake route for the phosphorus. These correlations suggest that, water column and sediments are important pathways for phosphorus uptake in plants.     

Response of thirsty rats to absence of water: Frustration,disinhibition or compensation?

Water-deprived rats were allowed to drink in an experimental chamber during a series of training trials, and were then presented with an empty water spout during a single test trial. Their initial response to absence of water was to bite, sniff and paw at the empty spout (spout-directed behaviour), after which they engaged in activities such as eating, grooming and exploration of the chamber. By comparison with control animals that had no expectation of water, experimental rats performed these latter activities in a bizarre ‘speeded-up’ manner, which was quantifiable as an increase in local rate. Both the occurrence of spout-directed behaviour and the increase in local rate of other activities were enhanced by increasing the prior level of water deprivation and by offering a more palatable fluid during training. The results are discussed in relation to current models of behavioural switching.     

Excited-state proton-transfer reactions of 7-azaindole with water,ammonia and mixed water–ammonia: microsolvated dynamics simulation

Dynamics simulations of excited-state multiple proton transfer (ESMPT) reactions in 7-azaindole (7AI) with ammonia, mixed water–ammonia, and water molecules were investigated by quantum dynamics simulations in the first-excited state using RI-ADC(2)/SVP-SV(P) in the gas phase. 7AI(WW), 7AI(WA), 7AI(AW) and 7AI(AA) clusters (W, water and A, ammonia) show very high probability of the excited-state triple proton transfer (ESTPT) occurrence in ranges from 20% for 7AI(WA) to 60% for 7AI(AW), respectively. Furthermore, 7AI(AW) clusters with ammonia placed near N–H of 7AI has the highest probability among other isomers. In 7AI with three molecules of bridged-planar of water, ammonia and mixed water–ammonia clusters, the excited-state quadruple proton transfer reactions occur ineffectively and rearrangement of hydrogen-bonded network on solvents also takes place prior to either ESTPT or excited-state double proton transfer. The role played by mixed-solvent is revealed with replacing H₂O with NH₃ in which the ESMPT is found to be more efficient corresponding to lower barrier in the excited state. The preferential number of solvent surrounding 7AI that facilitates the proton transfer process is two for methanol and water but this preferential number for ammonia is one.

Highlights: (i) replacing H₂O with NH₃ assists ESPT corresponding to lower barrier in the excited state; (ii) the ESMPT time of 7AI with mixed water–ammonia is in the sub-picosecond timescale; (iii) the PT tends to be concerted process with at least one ammonia, but synchronous without ammonia.     

Photosynthesis and stomatal conductance of potato leaves—effects of leaf age,irradiance, and leaf water potential

Potatoes (Solanum tuberosum L., cv. Bintje) were grown in a naturally lit glasshouse. Laboratory measurements on leaves at three insertion levels showed a decline with leaf age in photosynthetic capacity and in stomatal conductance at near saturating irradiance. Conductance declined somewhat more with age than photosynthesis, resulting in a smaller internal CO₂ concentration in older relative to younger leaves. Leaves with different insertion number behaved similarly. The changes in photosynthesis rate and in nitrogen content with leaf age were closely correlated. When PAR exceeded circa 100 W m^–2 the rate of photosynthesis and stomatal conductance changed proportionally as indicated by a constant internal CO₂ concentration. The photosynthesis-irradiance data were fitted to an asymptotic exponential model. The parameters of the model are AMAX, the rate of photosynthesis at infinite irradiance, and EFF, the slope at low light levels. AMAX declined strongly with leaf age, as did EFF, but to a smaller extent. During drought stress photosynthetic capacity declined directly with decreasing water potential (range –0.6 to –1.1 MPa). Initially, stomatal conductance declined faster than photosynthetic capacity.Abbreviations LNx leaf number x, counted in acropetal direction - DAP days after planting - DALA days after leaf appearance - C_i CO₂ concentration in the leaf - C_a CO₂ concentration in ambient air - LWP leaf water potential - OP osmotic potential - PAR photosynthetically active radiation     

A molecular dynamics simulation study of the effect of water–graphene interaction on the properties of confined water

The role of water in determining the structure and stability of biomacromolecules has been well studied. In this work, molecular dynamics simulations have been applied to investigate the effect of surface hydrophobicity on the structure and dynamics of water confined between graphene surfaces. In order to evaluate this effect, we apply various attractive/repulsive water–graphene interaction potentials (hydrophobicity). The properties of confined water are studied by applying a purely repulsive interaction potential between water–graphene (modelled as a repulsive r^?12 potential) and repulsive–attractive forces (modelled as an LJ(12-6) potential). Compared to the case of a purely repulsive graphene–water potential, the inclusion of repulsive–attractive forces leads to formation of sharp peaks for density and the number of hydrogen bonds. Also, it was found that repulsive–attractive graphene–water potential caused slower hydrogen bonds dynamics and restricted the diffusion coefficient of water. Consequently, it was found that hydrogen bond breakage and formation rate with the repulsive r^?12 potential model, will increase compared to the corresponding water confined with the LJ(12-6) potential.     

The sulfate-reducing bacterial community of sulfide-rich water of the Ust’-Kachka resort spring, Perm Krai, Russia

Microbiological investigation of the highly mineralized, sulfide-rich cold spring of the Ust??-Kachka resort was carried out. The total number and biomass of microbial cells were 50 × 10³ cell/mL and 15 ??g/L, respectively. While the total microbial number was low, the sulfate reduction rate determined by the radioisotope method was relatively high (0.575 mg S L^?1 day^?1). An enrichment culture was obtained on Widdel medium. According to the results of cloning the 16S rRNA gene fragments with subsequent restriction analysis, the dominant organisms were group 6 sulfate-reducing bacteria (Desulfovibrio-Desulfomicrobium) and the microorganism exhibiting 99% similarity to the anaerobic haloalkaliphilic bacterium Halanaerobium hydrogeniformans.     

State of Lake Sysmäjärvi,Eastern Finland,after loading with mine water and municipal waste water for several decades

Hydrobiologia - The deep mining of copper and nickel at Outokumpu, Eastern Finland, lasted from 1910 to the late 1980s, during which period metalliferous waste water of high conductivity and...     

The effect of counterion,water concentration,and stirring on the stability of subtilisin BPN′ in organic solvents

The stability of subtilisin BPN′ in organic solvents or cosolvent/water mixtures was studied as a function of the type and concentration of counterion at the time of freeze-drying, water concentration, and stirring speed/method. It was found that the enzyme is stabilized by high concentrations of counterion, at least at very high cosolvent concentrations. The type of counterion also has a remarkable impact on the enzyme stability; at high concentrations of DMF (dimethylformamide), multivalent counterions with low solubility in organic solvents are far superior to monovalent, soluble ones. Sodium citrate is the best salt tested in terms of enzyme stability, increasing the half life of the enzyme better than a millionfold over Tris in 99% DMF. The stability of the enzyme was found to have a complex dependence on the amount of water in the DMF. Enzyme lyophilized from the sodium phosphate displays a stability minimum at about 90% DMF, while enzyme lyophilized from Tris becomes increasingly unstable from 30% to 99% DMF, without inflection. Vigorous stirring with a magnetic stir bar, which broke apart the enzyme particles, was found to be extremely deleterious to enzyme stability, while swirling the enzyme with a wrist-action stirrer, which did not grind the enzyme particles, had no effect. Explanations for this are discussed.     

Shallow water marine gammaridean amphipods of Pulau Tioman,Malaysia, with the description of?a?new?species

Eleven taxa including one new species of gammaridean amphipods are reported from the waters of Pulau Tioman. The presence of Tethygeneia sunda sp. n. represents the first record of the genus from the South China Sea. Additional material of Ampelisca brevicornis (Costa, 1853); Cymadusa vadosa Imbach, 1967; Paradexamine setigera Hirayama, 1984; Ericthonius pugnax (Dana, 1853); Leucothoe furina (Savigny, 1816); Microlysias xenokeras (Stebbing, 1918); Monoculodes muwoni Jo, 1990 are identified from the South China Sea, supporting previous records by Lowry (2000), Huang (1994), Imbach (1967), Margulis (1968) and Nagata (1959). Three additional species, Gitanopsis pusilla K.H. Barnard, 1916, Liljeborgia japonica Nagata, 1965b and Latigammaropsis atlantica (Stebbing, 1888), whilst previously reported from the neighbouring waters, comprise new records for the South China Sea.     

Disentangling the relative effects of ambient energy,water availability,and energy–water balance on pteridophyte species richness at a landscape scale in China

Understanding what factors generate geographic variation in species richness is a fundamental goal of ecology and biogeography. Water and energy are considered as the major environmental factors influencing large-scale patterns of species richness, but their roles vary among taxa and regions. Pteridophytes are an ideal group of organisms for examining the relationship between species richness and their environment because the distribution of pteridophytes is usually in equilibrium with contemporary climate to a greater degree than those of seed plants and most terrestrial vertebrates partly due to the lightness of their spores, which is highly capable of long-distance dispersal by wind, and partly due to their single-spore reproduction strategy. Using correlation and regression analyses and structural equation modeling technique, we examine the relationship of pteridophyte species richness in 151 localities from across China with environmental factors representing energy, water, and energy–water balance. We found that pteridophyte species richness is correlated to water availability more strongly than to ambient energy. Furthermore, we found that of all environmental variables considered, energy–water balance has played the most important role in regulating pteridophyte species richness gradients in China.     

Cubic phases of ternary amphiphile–water systems

The reversed cubic phases (Q_II) are a class of self-assembled amphiphile–water structures that are rich in diversity and structural complexity. These nanostructured liquid crystalline materials are generating much interest owing to their unique surface morphology, biological relevance and potential technological and medical applications. The structure of Q_II phases in binary amphiphile–water systems is affected by the molecular structure of surfactant, water content, temperature and pressure. The presence of additives also plays an important role. The structure and phase behaviour of ternary Q_II phases, which are comprised of two miscible amphiphiles and water, significantly differ from the binary system alone. The modulation of the phase behaviour through the addition of a second amphiphile offers an opportunity to control the size and shape of the nanostructures using a ‘bottom-up’ approach. In this mini-review, we discuss the structure of reversed cubic phases of amphiphile–water systems and highlight the modulation of cubic-phase structure in ternary-phase systems. We also extend this review to bulk cubic phases and the corresponding nanoscale dispersions, cubic-phase nanoparticles.     

Does the temperature sensitivity of decomposition of soil organic matter depend upon water content,soil horizon,or incubation time?

Several studies have shown multiple confounding factors influencing soil respiration in the field, which often hampers a correct separation and interpretation of the different environmental effects on respiration. Here, we present a controlled laboratory experiment on undisturbed organic and mineral soil cores separating the effects of temperature, drying–rewetting and decomposition dynamics on soil respiration. Specifically, we address the following questions:

• 1 Is the temperature sensitivity of soil respiration (Q₁₀) dependent on soil moisture or soil organic matter age (incubation time) and does it differ for organic and mineral soil as suggested by recent field studies.
• 2 How much do organic and mineral soil layers contribute to total soil respiration?
• 3 Is there potential to improve soil flux models of soil introducing a multilayer source model for soil respiration?

Eight organic soil and eight mineral soil cores were taken from a Norway spruce (Picea abies) stand in southern Germany, and incubated for 90 days in a climate chamber with a diurnal temperature regime between 7 and 23°C. Half of the samples were rewetted daily, while the other half were left to dry and rewetted thereafter. Soil respiration was measured with a continuously operating open dynamic soil respiration chamber system. The Q₁₀ was stable at around 2.7, independent of soil horizon and incubation time, decreasing only slightly when the soil dried. We suggest that recent findings of the Q₁₀ dependency on several factors are emergent properties at the ecosystem level, that should be analysed further e.g. with regard to rhizosphere effects. Most of the soil CO₂ efflux was released from the organic samples. Initially, it averaged 4.0 μmol m^?2 s^?1 and declined to 1.8 μmol m^?2 s^?1 at the end of the experiment. In terms of the third question, we show that models using only one temperature as predictor of soil respiration fail to explain more than 80% of the diurnal variability, are biased with a hysteresis effect, and slightly underestimate the temperature sensitivity of respiration. In contrast, consistently more than 95% of the diurnal variability is explained by a dual‐source model, with one CO₂ source related to the surface temperature and another CO₂ source related to the central temperature, highlighting the role of soil surface processes for ecosystem carbon balances.     

Color change of lake water at the active crater lake of Aso volcano, Yudamari, Japan: is it in response to change in water quality induced by volcanic activity?

One feature of volcanic lakes influenced by subaqueous fumaroles existing at lake bottoms (called active crater lakes) is the remarkable color of their waters: turquoise or emerald green. The active crater lake named Yudamari at Mt. Nakadake of Aso volcano, Japan, takes on a milky pale blue-green. The particular blue component of the lake water color results from Rayleigh scattering of sunlight by very fine aqueous colloidal sulfur particles; the green component is attributable to absorption of sunlight by dissolved ferrous ions. An objective color observation conducted during 2000–2007 revealed that the lake water color changed from blue-green to solid green. The disappearance of the blue ingredient of the water color will result in diminution of aqueous colloidal sulfur from chemical analyses of lake waters sampled simultaneously. The aqueous sulfur is produced by the reaction of sulfur dioxide and hydrogen sulfide supplied from subaqueous fumaroles. However, its production efficiency decreases by domination of sulfur dioxide in the subaqueous fumarolic sulfur gas species with increasing subaqueous fumarolic temperature. The disappearance of blue ingredients from the blue-green color of the lake water may be attributed to activation of subaqueous fumarole activity.     

Does pre-dawn water potential reflect conditions of equilibrium in plant and soil water status?

Variation in base water potential (Ψ_b, a daily maximum level of plant water potential, which is presumed to correspond to the equilibrium between soil and plant water potentials) was examined in shoots of Picea abies and Vaccinium myrtillus with respect to soil (available water storage, water potential, temperature) and atmospheric (temperature, relative humidity, vapour pressure deficit) conditions. The available soil water storage (W_tr) accounted for 77% of the dynamics of Ψ_b, while the influence of atmospheric factors became evident under high evaporative demand. Ψ_b was not always observable immediately before dawn, but on 30% of observation days, the recovery continued up to an hour or two after dawn. Full equilibrium between soil and plant water potentials in P. abies in northern conditions is rather improbable by dawn in summer-time, because of the shortness of the dark period and probable night-time transpiration in the case of high atmospheric vapour pressure deficit.