Physical and hydraulic properties

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Soil physical and hydraulic properties in the Donato stream basin, RS, Brazil. Part 2: Geostatistical simulation

Soil physical and hydraulic properties in the Donato stream basin, RS, Brazil. Part 2: Geostatistical simulation

ABSTRACT: Geostatistical simulation has been the most promising and used technique for the analysis of uncertainties of soil physical and hydraulic properties, with high spatial heterogeneity. This study carried out a stochastic analysis of saturated hydraulic conductivity (K sat ) and soil water retention curve parameters in the Donato stream basin, located in the municipality of Pejuçara, in the state of Rio Grande do Sul, Brazil, with geographic coordinates between 28º 25’ 34” S and 53º 40’ 30” W, and 28º 24’ 50” S and 53º 41’ 30” W, 590 m of altitude. Soil samples were collected during the period from August to November of 2012. Sequential Gaussian simulation technique was used to generate 100 random fields of each variable. The results showed great uncertainties for K sat and the parameter α of the soil water retention curve. The uncertainties between the percentiles 5 and 95% for K sat indicated values from 24 to 44 cm d -1 , and for the parameter α, the uncertainties
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Biochar and its influence on soil physical and hydraulic properties

Biochar and its influence on soil physical and hydraulic properties

months) on soil physical (bulk density, porosity and pore size distribution and aggregate stability) and hydraulic properties (water holding capacity and water available content and hydraulic conductivity). To verify the best BC particle size to be applaied on the soil, a third study was developed to test the effect of BC particle size (<0.15; 0.15-2 and >2mm) in clay loam and sandy soil and to analyze its effects on soil chemical, physical and hydraulic properties. In the frist study (effect of BC rate on laboratory condition) a positive effect of BC rate on water availability, microporosity, and on water retention was found, especially for clay loam soil at high BC application, but this influence did not occur for sandy soil, possibly due to the short time of interaction. In the second study (effect of BC rate and FC on physical, chemical ans hydraulic porperties) the bulk density slightly decreased, and the porosity increased after nine months of interaction upon FC + BC 25 Mg ha -1 . However, after 18 months, the FC + BC amount altered the pore size distribution with an increase
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PHYSICAL-HYDRAULIC PROPERTIES OF A SANDY LOAM TYPIC PALEUDALF SOIL UNDER ORGANIC CULTIVATION OF 'MONTENEGRINA' MANDARIN (Citrus deliciosa TENORE)

PHYSICAL-HYDRAULIC PROPERTIES OF A SANDY LOAM TYPIC PALEUDALF SOIL UNDER ORGANIC CULTIVATION OF 'MONTENEGRINA' MANDARIN (Citrus deliciosa TENORE)

Citrus plants are the most important fruit species in the world, with emphasis to oranges, mandarins and lemons. In Rio Grande do Sul, Brazil, most fruit production is found on small properties under organic cultivation. Soil compaction is one of the factors limiting production and due to the fixed row placement of this crop, compaction can arise in various manners in the interrows of the orchard. The aim of this study was to evaluate soil physical properties and water infiltration capacity in response to interrow management in an orchard of mandarin (Citrus deliciosa Tenore ‘Montenegrina’) under organic cultivation. Interrow management was performed through harrowing, logs in "V", mowing, and cutting/knocking down plants with a knife roller. Soil physical properties were evaluated in the wheel tracks of the tractor (WT), between the wheel tracks (BWT), and in the area under the line projection of the canopy (CLP), with undisturbed soil samples collected in the 0.00-0.15, 0.15-0.30, 0.30-0.45, and 0.45-0.60 m layers, with four replicates. The soil water infiltration test was performed using the concentric cylinder method, with a maximum time of 90 min for each test. In general, soil analysis showed a variation in the physical-hydraulic properties of the Argissolo Vermelho-Amarelo distrófico arênico (sandy loam Typic Paleudalf) in the three sampling sites in all layers, regardless of the management procedure in the interrows. Machinery traffic leads to heterogeneity in the soil physical-hydraulic properties in the interrows of
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Soil physical and hydraulic properties in the Donato stream basin, RS, Brazil. Part 1: Spatial variability

Soil physical and hydraulic properties in the Donato stream basin, RS, Brazil. Part 1: Spatial variability

Due to the fact that they are clayey soils, it is possible that this fact explains why, in general, at points where K sat is smaller, θ sat is higher. This is because clay particles do not facilitate infiltration near saturation, reducing hydraulic conductivity and causing the soil to lose water through evaporation. Moreover, according to Hu et al. (2008), soil water flow is more affected by clay content when the soil becomes dry, which happened during the first soil sampling. All samples of lower θ sat values located in the northwestern portion of the basin (Figure 3D) were obtained when the soil was very dry, during the drought that began in November 2011 and continued until August 2012.
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Data of hydraulic properties of North East and North Central German soils

Data of hydraulic properties of North East and North Central German soils

Abstract. The paper presents a data base of soil physical and hydrological properties of North East and North Central German soils. Included are measured data of the soil water retention curve and the unsaturated hydraulic conductivity function. Information on geo-reference, soil type and horizon are given. Soil hydraulic functions were measured with the evaporation method. The applied measurement technique is described and information to actual innovations and advanced technology is given. Additional soil physical data like particle size distribution, dry bulk density, organic matter content and other variables are presented. The data base includes original measurement results of 278 organic and of 497 mineral soil samples from 103 sites. The mineral soils cover a wide range of texture classes and dry bulk densities. The organic soils and samples represent different states of decomposition and mineralization. Furthermore hydraulic functions are included of soils anthropogenically altered by deep plough sand covering measures.
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Effects of cover crops on soil hydraulic properties and yield in a persimmon orchard

Effects of cover crops on soil hydraulic properties and yield in a persimmon orchard

In agricultural systems, cover crops, especially legumes are usually incorporated into cropping systems to improve soil and plant quality attributes (Fageria et al. 2005). Cover crops improve soil quality, but the impacts on crop yield largely depend on the type of cover crops, main crops and climate conditions (Alvarez et al. 2017). Cover crops can also provide significant contributions to soil fertility (Robacer et al. 2016). They also increase soil organic matter content, stimulate repelling forces among soil particles through negative charges over clay particles, and thus increase dispersion of soil colloids (Emerson 1984). Cropping systems play an important role in soil physical properties, since they improve soil structure through several mechanisms, such as aggregate enrichment by fine roots and associated fungal hyphae, stimulation of microbial carbohydrate production or modified soil–water relationshi ps (Tisdall and Oades 1982; Angers 1998).
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STABILIZATION OF SOIL HYDRAULIC PROPERTIES UNDER A LONG TERM NO-TILL SYSTEM

STABILIZATION OF SOIL HYDRAULIC PROPERTIES UNDER A LONG TERM NO-TILL SYSTEM

Measurement of soil physical properties such as hydraulic conductivity (K) at different soil water pressure heads, and quantification of water-conducting macroporosity (ε ma ) and total macroporosity (θ ma ) is important for improving understanding of soil physical behavior. The properties of the soil macropore network, i.e., macropore volume fraction and diameter and continuity of macropores, have a big impact on the infiltration characteristics of agricultural soils (Hillel, 1998). Studies to quantify macropore flow revealed that more than 70 % of water flux can move through macropores (Watson & Luxmoore, 1986; Wilson & Luxmoore, 1988). In general, the water flow through structured soils is mainly conducted by macropores, even though they constitute only a very small fraction of total porosity (Cameira et al., 2003). The tension disc infiltrometer is a valuable tool for understanding water movement through macropores and the soil matrix near saturation (Watson & Luxmoore, 1986; Logsdon & Jaynes 1993; Moret & Arrúe, 2007), and for studying the effects of different practices on soil surface hydraulic properties (Malone et al., 2003; Moret & Arrúe, 2007). This device allows estimation of K from saturation to a few centimeters of suction head (Angulo-Jaramillo et al., 2000; Soracco, 2009) and quantification of the role of macropores during infiltration (Bodhinayake et al., 2004). This technique requires only minimal disturbance of the soil.
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Bayesian estimation of the hydraulic and solute transport properties of a small-scale unsaturated soil column

Bayesian estimation of the hydraulic and solute transport properties of a small-scale unsaturated soil column

Due to correlation of the residuals observed in Figures 8 and 10, a final analysis was performed in order to investigate the possibility of the measurements themselves being correlated. The parameters were again estimated by successively using only half of the measurements, that is, by halving the frequency of the original measurements. However, the estimated parameters and the residuals obtained with 50% and 25% of the original measurements were practically the same as those observed when 100% of the measurements were used. Therefore, the correlated residuals can be attributed to the strong linear dependency of the physical parameters shown in Figures 5–7, as well as to some mismatch between the adopted mathematical model and the physical processes of the problem. On the other hand, the small residuals observed for the measured concentration validate the use of the dual-porosity physical non-equilibrium model, in particular the hypotheses of having a constant f (see Equations 12a,b) and a non-reactive
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Mechanical and mineralogical properties of natural hydraulic lime-metakaolin mortars in different curing conditions

Mechanical and mineralogical properties of natural hydraulic lime-metakaolin mortars in different curing conditions

Nowadays, it is well known that PC mortars present several problems regarding their use in restoration of historical structures containing lime mortars. Some of the main problems are associated to their incompatibility in terms of mechanical, physical and chemical properties [8,9]. To prevent the damage and deterioration of these historic structures it is recommended that repairs be carried out by lime-based mortars, which encompasses the use of hydraulic mortars with low strength capacity and without soluble salt contamination problems.
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New natural hydraulic lime mortars – Physical and microstructural properties in different curing conditions

New natural hydraulic lime mortars – Physical and microstructural properties in different curing conditions

The test of water absorption by capillarity was based on the European standards EN 1015–18:2002 [26] and EN 15803:2009 [27]. The mortar specimens were placed in an oven at 60°C for a minimum of 48 hours for mass stabilization. The specimens were laterally wrapped in polyethylene film to waterproof the lateral surfaces, dry weighed and then vertically placed in a watertight box over an open grid, under stable hygroscopic conditions, with water depth of 5 mm. Mortar specimens were weighed after 5, 10, 15, 30 minutes and at each hour until 9 hours of testing, and then weighed every day until the mortars reached a mass difference lower than 1% in 24 hours. Values of absorbed water mass lead to the capillary absorption curve, Figure 4, relating in the abscissae axis the root of time in minutes ( in min 1/2
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PHYSICAL-CHEMICAL, MICROBIOLOGICAL AND SENSORY PROPERTIES OF FRUCTOOLIGOSACCHARIDES ENRICHED YOGURT

PHYSICAL-CHEMICAL, MICROBIOLOGICAL AND SENSORY PROPERTIES OF FRUCTOOLIGOSACCHARIDES ENRICHED YOGURT

These foods should also be beyond basic nutrition. For a human being as assessed, his health properties should be scientific evidence. For example, foods that are low in fats and sugars or fiber incorporated, among others, are foods.The prebiotics are among the functional foods that are defined as the non- digestible carbohydrates that stimulated the growth of the prebiotic bacteria in the intestine (KÜSTER-BOLUDA; VIDAL-CAPILLA, 2013; NOLE et al., 2014).

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Soil physico-hydraulic properties under organic conilon coffee intercropped with tree and fruit species

Soil physico-hydraulic properties under organic conilon coffee intercropped with tree and fruit species

Abstract – The objective of this work was to evaluate the cultivation effects of organic conilon coffee (Coffea canephora) intercropped with tree and fruit species on soil physico-hydraulic properties. Conilon coffee managements in the organic system were: T1, full-sun monoculture; T2, T3, T4, and T5, intercropping with peach palm (Bactris gasipae), gliricidia (Gliricidia sepium), banana (Musa sp.), and inga (Inga edulis), respectively; and T6, an area of secondary native forest used as a control. The evaluated soil physico-hydraulic properties were: bulk density, porosity, plant-available water capacity, soil-penetration resistance, soil-water content, soil temperature, and least limiting water range. Conilon coffee intercropped with peach palm and gliricidia resulted in lower soil bulk density and penetration resistance, and in higher total porosity, microporosity, and soil-water content. Organic coffee shaded with peach palm and gliricidia improve the soil physico-hydraulic quality, in comparison with the soil under monoculture in full sun and with the soil of secondary native forest.
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Physical ProPerties of an alfisol and no-till soybean yield (1)

Physical ProPerties of an alfisol and no-till soybean yield (1)

these results show that in ntac, heavy machinery traffic on the surface, especially when poorly drained, has a greater tendency to degrade the soil (lower values for oM, fl and Ma and a higher bd value) (tavares filho et al., 2001; bertol et al., 2001; beutler et al., 2001; neves et al., 2007). furthermore, the results reported by tavares filho et al. (2006) and domingos et al. (2009) on clayey soils under different management systems show that chiseling significantly increases water infiltration under no tillage (increased macropore volume), although the authors state that this effect lasts no more than a year. on the other hand, no tillage (avoiding soil disturbance) with crop rotation (ntacr), as well as the plant residues left on the soil surface, helps maintain and improve the soil physical properties.
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CHEMICAL AND PHYSICAL PROPERTIES OF ORGANIC RESIDUES

CHEMICAL AND PHYSICAL PROPERTIES OF ORGANIC RESIDUES

HCl were added to dissolve all the ash. An aliquot of 1 mL was taken from the extract obtained above, to be mixed in glass vials with 4.0 mL of curcumin dissolved in oxalic acid. These bottles were kept in a water bath at 55–58 °C until complete evaporation of the whole extract. After cooling, 25 mL of 95 % ethyl alcohol was added and stirred into the vials to dissolve any residue. These extracts were analyzed with a colorimeter, and the readings were taken at a wavelength of 540 nm to determine total B. The electrical conductivity and pH were determined at the ratio residue:water of 1:2 and the samples were centrifuged for 20 min at 220 rpm (Abreu et al., 2006). The method of self-compacting (Brazil, 2007) was used to determine bulk density. A 500 mL plastic beaker was filled to the 300 mL mark with substrate. Then, this cylinder was lifted and dropped 10 times, falling under the action of its own weight from a height of 10 cm. With a spatula, the surface was slightly leveled and the volume (mL) read. Then, the material was weighed (g) by subtracting the mass of the beaker. The moisture of each material used in the self-compression was determined, to calculate the density based on dry weight. The procedure was repeated three times using different subsamples.
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Gold processing residue from Jacobina Basin: chemical and physical properties

Gold processing residue from Jacobina Basin: chemical and physical properties

Table 1 presents the concentration of the major constituents of the gold processing residue and table 2 the concentration of the trace elements. The analytical method used for the determination of each element is also presented in these tables, and in several cases an element was analyzed using distinct sample and more than one method. This procedure is useful to confirm the results, evaluate the detection limit of the analytical method, and to give an idea about the sample homoge- neity of the samples. As indicated by the mineralogical characterization, the main constituents of the residue are silica and iron oxide that account for about 95% of the weight. The sample also has some aluminum, mag- nesium, and potassium. Among the trace elements, the most abundant are: arsenic, barium, cerium, chromium, copper, lead, manganese nickel, titanium, tungsten, va- nadium, zinc, and zirconium. Several of these elements came from the granites of the Jacobina geologic region (Milesi et al., 2002, Barbosa and Dominguez, 1996; Klein, 2002).
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Physical properties of Physalis Peruviana L.

Physical properties of Physalis Peruviana L.

To determine the texture attributes (skin strength and elasticity) 100 berries were randomly selected as representative of the sample. The analyzes were performed with a texturometer TA.XT Plus, from Stable Micro Systems, using a 2 mm probe (P/2), with the following test conditions: pre-test speed = 1.50 mm/s, test-speed = 1.00 mm/s, post-test speed = 10.00 mm/s, distance = 6 mm, trigger force = 0.05 mm and a load cell of 50 kg. The results were treated with Exponent software TEE (Stable Micro Systems) and from the obtained texture profile (Figure 2) was determined firmness (strength on the highest peak) and elasticity (distance at the highest point). The number of samples used for texture evaluation was 100.
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Physical properties of Physalis peruviana L

Physical properties of Physalis peruviana L

Exotic fruits play an important role in nutrition and are an excellent base for dietetic products due to their benefi- cial bioactive compounds and low energetic value. Highly valued for its unique flavour, texture and colour, recent research has shown Physalis peruviana L. fruit to be rich in many beneficial compounds [1, 2]. For instance, the physalis fruit is rich in pro-vitamin A, ascorbic acid, and in some vitamins of the B complex (thiamine, niacin, and vitamin B 12 ). Additionally, the fruit is rich in crude protein, phosphorous and iron, although calcium content is low [3]. Some of the health benefits of physalis include: blood purification, reduction of the albumin in the kidneys, reconstruction and strengthening of the optic nerve, alle- viation of throat infections, elimination of intestinal par- asites, and treatment of prostate problems [3].
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Physical Properties of Wood from Steamed

Physical Properties of Wood from Steamed

This study aimed to evaluate the effect of log steaming on the physical properties of Eucalyptus grandis Hill ex Maiden wood. Logs with diameters between 20 and 25 cm and length of 2.9 m were studied. Half the logs were maintained in their original condition, and the other half were steamed at 90 °C for 20 hours. Later, the logs were sawn into flat boards, and samples were removed to determine the physical properties of the wood. The results showed that log steaming caused a significant decreases of: (1) 6.38% and 7.98% in the respective basic and oven dried density; and (2) 7.20%, 7.80%, 5.13%, and 8.56% in the volumetric, tangential, radial, and axial linear swelling of wood.
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Physical-chemical properties of blueberry as influenced by production and conservation processes

Physical-chemical properties of blueberry as influenced by production and conservation processes

The color of blueberries was determined with a colorimeter (Chroma Meter - CR-400, Konica Minolta) in the CIE Lab color space, though the Cartesian coordinates L*, a* and b*. The L* axis represents Lightness and varies from 0 (corresponding to no lightness, i.e., absolute black), to 100 which is maximum lightness (i.e. absolute white). The other axes are represented by a* and b* and they are at right angles to each other. The a* axis varies from green at one extremity (represented by -a) to red at the other (+a), whereas the b* axis varies from blue at one end (-b), to yellow (+b) at the other. Although in theory there are no extreme values of a* and b*, in practice they can be numbered from -128 to +127.
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Physical, chemical and sensory properties of kiwi as influenced by drying conditions

Physical, chemical and sensory properties of kiwi as influenced by drying conditions

The fresh kiwi was used as the reference and a larger ∆ E denotes a greater colour change from the reference material. 2.8 Evaluation of texture Texture profile analysis (TPA) to all the samples was performed using a Texture Analyser (model TA.XT.Plus, from Stable Micro Systems, Godaming, Surrey, United Kingdom). The TPA was performed by two compression cycles between parallel plates, with a five seconds interval, using a flat 75 mm diameter plunger (P/75) and a 5 kg force load cell. The pre-test, test and post-test speed was 1.5 m m s - 1 , in all cases. Eight measurements were done for each sample and then the textural properties: firmness, adhesiveness, springiness, resilience, cohesiveness, and chewiness were calculated by Equations 2 to 7 (see Figure 3) (Guiné and Barroca, 2012; Santos et al., 2013): Firmness (N) = F1. (2)
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