scholarly journals Experimental study on the effect of temperature and flux conditions on moisture distribution in vadose zone soil

2016 ◽  
Vol 75 (4) ◽  
pp. 881-889 ◽  
Author(s):  
Jinguo Wang ◽  
Hu Zheng
Keyword(s):  
Moisture Content ◽  
Vadose Zone ◽  
Soil Depth ◽  
Soil Column ◽  
Moisture Distribution ◽  
Effect Of Temperature ◽  
Land Productivity ◽  
Temperature Changes ◽  
The Difference ◽  
Study Laboratory

Moisture distribution in vadose zone soil is the most important parameter for land productivity and vegetation status of ecological systems, and is sensitive to temperature variation. In this study, laboratory scale tests were conducted to determine the effect of temperature on variation in moisture distribution in covered and uncovered conditions. The results indicated that soil moisture from 2.65 to 20 cm was positively correlated with temperature and temperature gradient, and the top 2.65 to 5 cm was dramatically influenced by temperature changes in both covered and uncovered conditions. The moisture content when temperature was increasing was higher than that when temperature was decreasing for the same temperature, when the film covered the top of the soil column. In contrast, the moisture content when temperature was increasing was lower than when the temperature was decreasing for the uncovered soil column. The difference between treatments was not maintained as soil depth increased.

Distribution of soil moisture content and its effect on the potential growth of the over-story species in North-East Chalkidiki

2001 ◽  
Vol 66 ◽  
Author(s):  
M. Aslanidou ◽  
P. Smiris
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Soil Depth ◽  
Moisture Distribution ◽  
Taxus Baccata ◽  
Mixed Stands ◽  
Potential Growth ◽  
North East ◽  
Soil Moisture Distribution

This  study deals with the soil moisture distribution and its effect on the  potential growth and    adaptation of the over-story species in north-east Chalkidiki. These  species are: Quercus    dalechampii Ten, Quercus  conferta Kit, Quercus  pubescens Willd, Castanea  sativa Mill, Fagus    moesiaca Maly-Domin and also Taxus baccata L. in mixed stands  with Fagus moesiaca.    Samples of soil, 1-2 kg per 20cm depth, were taken and the moisture content  of each sample    was measured in order to determine soil moisture distribution and its  contribution to the growth    of the forest species. The most important results are: i) available water  is influenced by the soil    depth. During the summer, at a soil depth of 10 cm a significant  restriction was observed. ii) the    large duration of the dry period in the deep soil layers has less adverse  effect on stands growth than in the case of the soil surface layers, due to the fact that the root system mainly spreads out    at a soil depth of 40 cm iii) in the beginning of the growing season, the  soil moisture content is    greater than 30 % at a soil depth of 60 cm, in beech and mixed beech-yew  stands, is 10-15 % in    the Q. pubescens  stands and it's more than 30 % at a soil depth of 60 cm in Q. dalechampii    stands.

Consideration of the temperature factor of atmospheric air when determining standard consumption of fuel and energy resources for train traction

2018 ◽  
Vol 77 (6) ◽  
pp. 375-381
Author(s):  
K. M. Popov
Keyword(s):  
Statistical Processing ◽  
Specific Consumption ◽  
Energy Resources ◽  
Effect Of Temperature ◽  
Influence Coefficient ◽  
Specific Work ◽  
Specific Flow ◽  
Temperature Changes ◽  
Work Area ◽  
Physical Laws

Abstract. Influence of air temperature on the consumption of fuel and energy resources (FER) on train traction is due to a number of physical laws. The extent of this effect is specified in the Rules for Traction Settlement (RTS). At the same time, when rationing FER consumption for train traction, a specialized methodical base is used, which involves a different approach to accounting for the effect of temperature on FER consumption for train traction. At the same time in different documents of this base, the effects of low temperature on the absolute and specific consumption of fuel and energy resources on train traction are taken into account in a different way, which is due to the lack of consensus among specialists on the way this factor is taken into account. Specialists of JSC “VNIIZhT” carried out an analysis of a significant amount of driver’s routes data, results of which showed that the dependence of the specific flow rate on temperature, on the basis of which the corresponding influence coefficient is determined, needs to be periodically updated. In addition, when technically standardizing the consumption of fuel and energy resources (for the locomotive crew work site), the temperature effect coefficients need to be calculated for a specific work area and direction of motion on it, while using the average network coefficient values will lead to errors. When calculating additional flow of fuel and energy from the effect of temperature for electric multiple units (EMU), the equations of regression dependencies should be used, obtained by statistical processing of data on temperature changes and specific consumption of fuel and energy resources for EMU and determined for each series of EMU when working on a particular suburban area.

scholarly journals The Respiration of some Planktonic copepods II. The Effect Of Temperature

1953 ◽  
Vol 31 (3) ◽  
pp. 447-460 ◽  
Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont
Keyword(s):  
Respiratory Rate ◽  
The Body ◽  
The Other ◽  
Effect Of Temperature ◽  
Acartia Clausi ◽  
Temora Longicornis ◽  
Different Temperatures ◽  
Planktonic Copepods ◽  
The Difference ◽  
The Relationship

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.

scholarly journals Calcium Biogeochemical Cycle in a Typical Karst Forest: Evidence from Calcium Isotope Compositions

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 666
Author(s):  
Guilin Han ◽  
Anton Eisenhauer ◽  
Jie Zeng ◽  
Man Liu
Keyword(s):  
Soil Depth ◽  
Isotope Composition ◽  
Soil Surface ◽  
Natural Soil ◽  
Calcium Isotope ◽  
Karst Forest ◽  
Content Ratio ◽  
The Difference ◽  
Preferential Uptake ◽  
Vital Factor

In order to better constrain calcium cycling in natural soil and in soil used for agriculture, we present the δ44/40Ca values measured in rainwater, groundwater, plants, soil, and bedrock samples from a representative karst forest in SW China. The δ44/40Ca values are found to differ by ≈3.0‰ in the karst forest ecosystem. The Ca isotope compositions and Ca contents of groundwater, rainwater, and bedrock suggest that the Ca of groundwater primarily originates from rainwater and bedrock. The δ44/40Ca values of plants are lower than that of soils, indicating the preferential uptake of light Ca isotopes by plants. The distribution of δ44/40Ca values in the soil profiles (increasing with soil depth) suggests that the recycling of crop-litter abundant with lighter Ca isotope has potential effects on soil Ca isotope composition. The soil Mg/Ca content ratio probably reflects the preferential plant uptake of Ca over Mg and the difference in soil maturity. Light Ca isotopes are more abundant in mature soils than nutrient-depleted soils. The relative abundance in the light Ca isotope (40Ca) is in the following order: farmland > burnt grassland > forests > grassland > shrubland. Our results further indicate that biological fractionation in a soil–plant system is a vital factor for Ca–geochemical transformations in soil surface systems.

scholarly journals Effect of Radial Moisture Distribution on Frequency Domain Dielectric Response of Oil-Polymer Insulation Bushing

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1219 ◽  
Author(s):  
Daning Zhang ◽  
Guanwei Long ◽  
Yang Li ◽  
Haibao Mu ◽  
Guanjun Zhang
Keyword(s):  
Moisture Content ◽  
Space Charge ◽  
Frequency Domain ◽  
Water Distribution ◽  
Space Charge Polarization ◽  
Moisture Distribution ◽  
Mechanism Analysis ◽  
Loss Peak ◽  
Charge Polarization ◽  
Peak Value

In order to realize the diagnosis of water distribution, this paper analyzes the interface polarization and macroscopic space charge polarization mechanism when the water distribution is non-uniform. The experimental results of this paper and bushing show that when the moisture distribution is non-uniform, there is a significant loss peak in the tanδ-f curve. The loss peak shifts to higher frequencies as the non-uniformity coefficient increases. There are common intersection points between multiple tanδ-f curves. Further, this paper realizes the diagnosis of the location of moisture distribution through Frequency Domain Spectroscopy (FDS) testing of different voltages and different wiring methods based on the macroscopic space charge polarization. In the single-cycle FDS test, when the positive electrode is first added to the area with higher moisture content, the amplitude of the tanδ-f curve is smaller. The tanδ-f curves under different wiring methods constitute a “ring-shaped” loss peak. As the voltage increases, the peak value of the loss peak shifts to the lower frequency band. As the temperature increases, the peak value of the loss peak shifts to higher frequencies. Based on the above rules and mechanism analysis, this research provides a new solution for the evaluation of moisture content of oil-immersed polymers equipment.

Flow Behaviors of High Acyl Gellan Aqueous Solutions as Affected by Temperature, and Calcium and Gellan Concentrations

2008 ◽  
Vol 4 (5) ◽  
Author(s):  
Yiqun Huang ◽  
Pawan Singh Takhar ◽  
Juming Tang ◽  
Barry G Swanson
Keyword(s):  
Shear Rate ◽  
Aqueous Solutions ◽  
Apparent Viscosity ◽  
Flow Resistance ◽  
Effect Of Temperature ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Rheological Behaviors ◽  
Low Concentrations ◽  
Influence Of Temperature On

Rheological behaviors of high acyl (HA) gellan are not well understood partially because of its relatively late commercialization compared to low acyl gellan. The objective of this study was to investigate the effect of temperature (5-30 °C), calcium (0, 1 and 10 mM) and gellan concentrations (0.0044-0.1000% w/v) on the flow behaviors of high acyl gellan aqueous solutions using rheological tests. Gellan solutions with 0 or 1 mM added Ca++ exhibited shear thinning behavior at gellan concentrations above 0.0125%. The influence of temperature on apparent viscosity (shear rate, 100 s-1) of gellan solutions can be described with an Arrhenius relationship. The apparent viscosity of gellan solution at low concentrations was more sensitive to temperature changes. The addition of Ca++ led to a decrease in flow resistance for a dilute gellan solution (<0.0125%), but an increased resistance for a relatively concentrated gellan solution (>0.0125%).

Effect of temperature and yeast extract on microbial respiration of sediments from a shallow coastal subsurface and vadose zone

1996 ◽  
Vol 57-58 (1) ◽  
pp. 827-835 ◽  
Author(s):  
Kirit D. Chapatwala ◽  
G. R. V. Babu ◽  
Onguri K. Vijaya ◽  
E. Armstead ◽  
A. V. Palumbo ◽  
...  
Keyword(s):  
Yeast Extract ◽  
Vadose Zone ◽  
Microbial Respiration ◽  
Effect Of Temperature
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