Estimating hydraulic conductivity of a sandy soil under different plant covers using minidisk infiltrometer and a dye tracer experiment

AbstractThe objective of this study was to estimate the hydraulic conductivity of sandy soil under different plant cover at the locality Mláky II at Sekule (southwest Slovakia). Two sites were demarcated at the locality, with mainly moss species at glade site, and pine forest at forest site. The estimation of unsaturated hydraulic conductivity was conducted by (a) minidisk infiltrometer and (b) the analysis of a dye tracer total resident concentration. The latter approach assumed the applicability of the stochastic—convective flow theory in the sandy soil. In the dye tracer experiment, two plots (1 × 1 m each) were established in both sites, and 100 mm of dye tracer (Brilliant Blue FCF) solution was applied on the soil surface. Similar results were obtained in both plots, with more than 70 % area of horizons stained in the depth of 30–50 cm. In some cases, the predicted and measured hydraulic conductivity were found within an order of magnitude, thus revealing similar impact of different plant cover on hydraulic properties of sandy soil studied. In contrast to sandy soils used for agriculture, the influence of the plant/surface humus and topsoil interface extended in the form of a highly heterogeneous matrix flow to the depth of 50–60 cm, where it was dampened by horizontal layering.

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Identification of preferential flow effects on hydraulic conductivity measurements using a fluorescent tracer

Canadian Geotechnical Journal ◽

10.1139/t99-113 ◽

2000 ◽

Vol 37 (2) ◽

pp. 479-484

Author(s):

Tom A Al ◽

David W Blowes

Keyword(s):

Hydraulic Conductivity ◽

Measurement Errors ◽

Preferential Flow ◽

Conductivity Measurements ◽

Fine Grained ◽

The Core ◽

Core Samples ◽

Dye Tracer ◽

Order Of Magnitude ◽

Constant Head

Core samples were collected from fractured and unfractured zones within fine-grained, unconsolidated mine tailings. The hydraulic conductivity of the core samples was measured in a constant-head permeameter. A fluorescent dye tracer was added to the constant-head reservoir in the permeameter. The tests were run for approximately 48 h, then the cores were sectioned to observe the distribution of dye. Flow through the fractures results in hydraulic conductivity measurements up to one order of magnitude greater than that of unfractured tailings. Observations of the dye distribution in samples following permeameter measurements are used to identify cases where preferential flow in fractures has influenced the hydraulic conductivity measurements. The dye tracer distribution also indicates where measurement errors may be suspected due to flow leakage around the core sample.Key words: tracers, hydraulic conductivity, fractures, tailings.

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The impact of vegetation on hydraulic conductivity of sandy soil

Soil and Water Research ◽

10.17221/2115-swr ◽

2008 ◽

Vol 2 (No. 2) ◽

pp. 59-66 ◽

Cited By ~ 10

Author(s):

L. Lichner ◽

T. Orfánus ◽

K. Novákova ◽

M. Šír ◽

M. Tesař

Keyword(s):

Hydraulic Conductivity ◽

Forest Soil ◽

Sandy Soil ◽

Preferential Flow ◽

Water Drop ◽

Water Repellency ◽

Forest Site ◽

Meadow Soil ◽

Capillary Suction ◽

The Impact

The objective of this study was to assess the impact of vegetation on the hydraulic conductivity of sandy soil at the locality Mláky II at Sekule (southwest Slovakia). The measurements were taken on the surface of a meadow (Meadow site), a 30-year old Scots pine (Pinus sylvestris) forest (Forest site) and a glade (Glade site). In the glade, the measurements were also taken in the depth of 50 cm (Pure sand) to reduce the influence of vegetation on the soil properties. It was found that the unsaturated hydraulic conductivity kr(−2 cm) as reduced due to the soil water repellency increased in the same order: Forest soil < Glade soil ≈ Meadow soil < Pure sand, similarly as decreased the water drop penetration time tp: Forest soil > Glade soil ≈ Meadow soil > Pure sand, which could refer to an inverse proportionality between the capillary suction and hydrophobic coating of the soil particles. The saturated hydraulic conductivity Ks increased in the following order: Meadow soil < Glade soil ≈ Forest soil < Pure sand; more than two-times higher Ks at both the Forest and Glade sites than that at the Meadow site could be the result of both the patchy growth of vegetation with some areas of bare soil at the Glade site and the macropores (dead roots) in more homogeneous humic top-layer at the Forest site. The share Br of flux through the pores with radii r longer than approximately 0.5 mm decreased in the order: Forest soil » Meadow soil > Glade soil » Pure sand, revealing the prevalence of preferential flow through macropores (dead roots) in the Forest site and a negligible share of macropores in the Pure sand.

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Coal Fly Ash and Polyacrylamide Influence Transport and Redistribution of Soil Nitrogen in a Sandy Sloping Land

Agriculture ◽

10.3390/agriculture11010047 ◽

2021 ◽

Vol 11 (1) ◽

pp. 47

Author(s):

Kai Yang ◽

Zejun Tang ◽

Jianzhang Feng

Keyword(s):

Fly Ash ◽

Sandy Soil ◽

Coal Fly Ash ◽

Soil Layer ◽

Nutrient Retention ◽

Soil Surface ◽

Rainfall Event ◽

N Losses ◽

N Concentration ◽

Application Rates

Sandy soils are prone to nutrient losses, and consequently do not have as much as agricultural productivity as other soils. In this study, coal fly ash (CFA) and anionic polyacrylamide (PAM) granules were used as a sandy soil amendment. The two additives were incorporated to the sandy soil layer (depth of 0.2 m, slope gradient of 10°) at three CFA dosages and two PAM dosages. Urea was applied uniformly onto the low-nitrogen (N) soil surface prior to the simulated rainfall experiment (rainfall intensity of 1.5 mm/min). The results showed that compared with no addition of CFA and PAM, the addition of CFA and/or PAM caused some increases in the cumulative NO3−-N and NH4+-N losses with surface runoff; when the rainfall event ended, 15% CFA alone treatment and 0.01–0.02% PAM alone treatment resulted in small but significant increases in the cumulative runoff-associated NO3−-N concentration (p < 0.05), meanwhile 10% CFA + 0.01% PAM treatment and 15% CFA alone treatment resulted in nonsignificant small increases in the cumulative runoff-associated NH4+-N concentration (p > 0.05). After the rainfall event, both CFA and PAM alone treatments increased the concentrations of NO3−-N and NH4+-N retained in the sandy soil layer compared with the unamended soil. As the CFA and PAM co-application rates increased, the additive effect of CFA and PAM on improving the nutrient retention of sandy soil increased.

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Analytical Model to Predict Nonhomogeneous Soil Temperature Variation

Journal of Solar Energy Engineering ◽

10.1115/1.2870823 ◽

1995 ◽

Vol 117 (2) ◽

pp. 100-107 ◽

Cited By ~ 7

Author(s):

M. Krarti ◽

D. E. Claridge ◽

J. F. Kreider

Keyword(s):

Thermal Properties ◽

Soil Temperature ◽

Temperature Variation ◽

Analytical Model ◽

Soil Surface ◽

Deep Soil ◽

Soil Thermal Properties ◽

Order Of Magnitude ◽

Soil Surface Temperature ◽

Annual Time

This paper presents an analytical model to predict the temperature variation within a multilayered soil. The soil surface temperature is assumed to have a sinusoidal time variation for both daily and annual time scales. The soil thermal properties in each layer are assumed to be uniform. The model is applied to two-layered, three-layered, and to nonhomogeneous soils. In case of two-layered soil, a detailed analysis of the thermal behavior of each layer is presented. It was found that as long as the order of magnitude of the thermal diffusivity of soil surface does not exceed three times that of deep soil; the soil temperature variation with depth can be predicted accurately by a simplified model that assumes that the soil has constant thermal properties.

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Evaluating the Efficiency of Crushed Gravel Filters around Field Drains

10.24086/aces2020/paper.224 ◽

2021 ◽

Author(s):

Amer Al-Haddad ◽

◽

Dhuha Mahdi ◽

Keyword(s):

Hydraulic Conductivity ◽

Soil Surface ◽

Filter Material ◽

Head Loss ◽

Surface Flow ◽

Laboratory Work ◽

Drain Pipe ◽

Drainage Systems ◽

Total Head ◽

Irrigation Condition

Engineers have employed various ways to protect drain openings from the entry of sediment with varying degrees of success. This study aims to compare and evaluate the hydraulic performance and efficiency of using natural graded gravel filter and crushed gravel filter in drainage systems. An aquifer tank (sand tank) 70 cm long, 50 cm wide and 80 cm high, a perforated drain pipe of 50 mm diameter was used in the laboratory work. The laboratory study was performed with two types of soil: loam and loamy sand. These two soils were used with the two types of gravel filters after taking the particle size distribution test for the two soils. For each case, the inflow was applied to the model from the soil surface (to represent irrigation condition) and from the sides of the tank (to represent sub –surface flow condition and effluence of the groundwater). Each case involved ten runs; for each run, discharge, total head loss, and amount of sediment were recorded. It was found that crushed gravel filter would work similarly to natural graded gravel filter after a certain time from the beginning of runs. It was also found that the discharge and sediment when using crushed gravel filter were close to or equal to that with natural graded gravel filter. The hydraulic conductivity and the exit gradient values were calculated in this research. It was found that their values were so different between the two types of filters, but at the end of the laboratory work, the hydraulic conductivity would be approximately the same. The exit gradient of crushed gravel filter was lower than that of natural graded gravel filter due to the large pores between the filter particles. Finally, the results showed that, it is possible to use crushed gravel filter material in drainage systems, which is less costly and easier to place than natural graded gravel filter.

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Estimation and Scaling of the Near-Saturated Hydraulic Conductivity

Hydrology Research ◽

10.2166/nh.1999.0010 ◽

1999 ◽

Vol 30 (3) ◽

pp. 177-190 ◽

Cited By ~ 1

Author(s):

Per Atle Olsen

Keyword(s):

Hydraulic Conductivity ◽

Saturated Hydraulic Conductivity ◽

Scaling Analysis ◽

Laboratory Measurements ◽

Estimation Errors ◽

Geometric Means ◽

Top Soil ◽

Structured Soils ◽

Order Of Magnitude

The hydraulic conductivity in structured soils is known to increase drastically when approaching saturation. Tension infiltration allows in situ infiltration of water at predetermined matric potentials, thus allowing exploration of the hydraulic properties near saturation. In this study, the near saturated (ψ≥-0.15 m) hydraulic conductivity was estimated both in the top- and sub-soil of three Norwegian soils. A priory analysis of estimation errors due to measurement uncertainties was conducted. In order to facilitate the comparison between soils and depths, scaling analysis was applied. It was found that the increase in hydraulic conductivity with increasing matric potentials (increasing water content) was steeper in the sub-soil than in the top-soil. The estimated field saturated hydraulic conductivity was compared with laboratory measurements of the saturated hydraulic conductivity. The geometric means of the laboratory measurements was in the same order of magnitude as the field estimates. The variability of the field estimates of the hydraulic conductivity from one of the soils was also assessed. The variability of the field estimates was generally smaller than the laboratory measurements of the saturated hydraulic conductivity.

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INFLUÊNCIA DA COMPACTAÇÃO E DO CULTIVO DE SOJA NOS ATRIBUTOS FÍSICOS E NA CONDUTIVIDADE HIDRÁULICA EM LATOSSOLO VERMELHO

Irriga ◽

10.15809/irriga.2003v8n3p242-249 ◽

2003 ◽

Vol 8 (3) ◽

pp. 242-249 ◽

Cited By ~ 1

Author(s):

Amauri Nelson Beutler ◽

José Frederico Centurion ◽

Cassiano Garcia Roque ◽

Zigomar Menezes de Souza

Keyword(s):

Hydraulic Conductivity ◽

Bulk Density ◽

Soil Compaction ◽

Soil Surface ◽

Total Porosity ◽

Soil Condition ◽

Agricultural Science ◽

Water Infiltration ◽

Loose Soil ◽

Physical Attributes

INFLUÊNCIA DA COMPACTAÇÃO E DO CULTIVO DE SOJA NOS ATRIBUTOS FÍSICOS E NA CONDUTIVIDADE HIDRÁULICA EM LATOSSOLO VERMELHO Amauri Nelson BeutlerJosé Frederico CenturionCassiano Garcia RoqueZigomar Menezes de SouzaDepartamento de Solos e Adubos, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Jaboticabal, SP. CEP 14870-000. E-mail: [email protected], [email protected] 1 RESUMO Este estudo teve como objetivo determinar a influência da compactação e do cultivo de soja nos atributos físicos e na condutividade hidráulica de um Latossolo Vermelho de textura média. O experimento foi conduzido na Universidade Estadual Paulista – Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal (SP). Os tratamentos foram: 0, 1, 2, 4 e 6 passadas de um trator, uma ao lado da outra perfazendo toda a superfície do solo, com quatro repetições. O delineamento experimental foi inteiramente casualizado para a condutividade hidráulica e, em esquema fatorial 5 x 2 para os atributos físicos. Foram coletadas amostras de solo nas faixas de profundidades de 0,02-0,05; 0,07-0,10 e 0,15-0,18 m, por ocasião da semeadura e após a colheita para determinação da densidade do solo, porosidade total, macro e microporosidade do solo. A condutividade hidráulica do solo foi determinada após a colheita. O tempo entre a semeadura e a colheita de soja foi suficiente para aumentar a compactação do solo apenas na condição de solo solto. A compactação do solo reduziu a condutividade hidráulica em relação a condição natural (mata) e a condição de solo solto, sendo que esta não foi reduzida, após a primeira passagem, com o aumento no número de passagens. UNITERMOS: Densidade do solo, porosidade do solo, infiltração de água, soja. BEUTLER, A. N.; CENTURION, J. F.; ROQUE, C. G.; SOUZA, Z. M. COMPACTION AND SOYBEAN GROW INFLUENCE ON PHYSICAL ATTRIBUTES AND HYDRAULIC CONDUCTIVITY IN RED LATOSSOL SOIL 2 ABSTRACT The purpose of this study was to determine the influence of compaction and soybean grow on physical attributes and hydraulic conductivity of a Red Latossol, medium texture soil. The experiment was carried out in the experimental farm at the Paulista State University – Agricultural Science College, Jaboticabal – São Paulo state. The treatments were 0, 1, 2, 4 and 6 side-by-side tractor strides on the soil surface with four replications. The experimental design was completely randomized for hydraulic conductivity and a 5 x 2 factorial design for soil physical attributes. Soil samples have been collected at 0.02-0.05, 0.07-0.10 and 0.15-0.18 m depth at sowing season and after harvest in order to determine soil bulk density, total porosity, macro and micro porosity. Soil hydraulic conductivity was determined after harvest. The time period between the soybean sowing and harvesting was enough to increase soil compaction only in loose soil condition. Soil compaction reduced hydraulic conductivity compared to the natural (forest) and loose soil condition KEYWORDS: Bulk density, soil porosity, water infiltration, soybean.

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Salinity Status of Lajas Valley Soils

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v41i1.12629 ◽

1969 ◽

Vol 41 (1) ◽

pp. 25-34

Author(s):

Juan A. Bonnet ◽

Eduardo J. Brenes

Keyword(s):

Electrical Conductivity ◽

Hydraulic Conductivity ◽

Soil Layer ◽

Soil Surface ◽

Exchangeable Sodium Percentage ◽

Exchangeable Sodium ◽

Surface Layers ◽

Alkali Soils ◽

The World ◽

Sodium Percentage

1. The area of soils surveyed in Lajas Valley was 24,656 acres. 2. The soils were classified into normal, saline, saline-alkali, and non- saline-alkali at depths of 0 to 8, 8 to 24, 24 to 48, and 48 to 72 inches, respectively. 3. A large percentage of normal soils was found in the upper soil layer and of saline-alkali soils in the lower layers. 4. Normal soils occupied about 86 percent of the surface area to a depth of 8 inches and about 63 percent at a depth of 8 to 24 inches. 5. Soils with a salinity problem increased from 9 percent at a depth of 8 inches to 28.3, 58.8 and 68.5 percent, respectively, at depths of 8 to 24, 24 to 48, and 48 to 72 inches. 6. The soils with a salinity problem were largely of the saline-alkali class. 7. In four soil-profile samples taken from Lajas Valley, the saturation percentage varied from 58 to 191, the electrical conductivity from 0.8 to 28.4 millimhos per centimeter, the exchangeable-sodium percentage from 2.2 to 46.0, the soil pH from 8.1 to 8.9, the content of gypsum from 0 to 21.9 tons per acre-foot, the gypsum requirement from 0 to 23.8 tons per acre-foot, and the hydraulic conductivity from less than 0.005 to 6.24 inches of water per hour. Higher gypsum contents were found in the deep subsoil layers of two soils (profiles 1 and 4). Amounts of gypsum varying from 9.9 to 20.3 tons per acre-foot of depth, are required for the reclamation of the surface layers of these two profiles. In general, the hydraulic- conductivity values show that the soil-surface layers are more permeable than the subsoil layers. 8. The procedure and methods used in this paper were found to be accurate, simple, rapid, and practical. They are recommended for the coordination of data related to the classification and reclamation of soils affected by salinity problems in the different countries of the world.

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Bryophytes on the devastated territories of sulphur deposits and their role in restoration of dump substrate

Biosystems Diversity ◽

10.15421/011850 ◽

2018 ◽

Vol 26 (4) ◽

pp. 339-353

Author(s):

I. V. Rabyk ◽

O. V. Lobachevska ◽

N. Y. Kyyak ◽

O. I. Shcherbachenko

Keyword(s):

Plant Cover ◽

Photosynthetic Apparatus ◽

Life Forms ◽

Climatic Conditions ◽

Projective Cover ◽

Biogenic Elements ◽

Moisture Regime ◽

Moss Species ◽

Vegetative Period ◽

Specific Composition

Bryophytes possess a wide ecological diapason allowing them to populate substrates of technogenic origins which are scarcely suitable or completely unsuitable for viability of vascular plants. 49 bryophyte species, which belong to 2 divisions, 3 classes, 8 orders, 17 families, and 33 genera have been found on the dump territory of sulphur extraction of the mining-chemical enterprise “Sirka” (Yavoriv district, Lviv region). Seven transects, three on the north slope (base, slope, top), three on the south slope and one on the plateau were laid for sample selections. 20 investigated 0.5 × 0.5 m plots located 2 m apart were analyzed within each 10 × 10 m transect. Specific composition, life forms, projective cover, biomass of bryophytes, numbers of male, female and sterile plants, moisture content in the turfs, pH and physiological investigation of mosses were determined on each plot. The quantitative analysis of the biomorphological structure allowed us to establish the dependence of the spread of life forms on exposition and slope height; essential variability of the projective cover and moss biomass. Bryophyte cover plays an essential part in optimization of the moisture regime and surface layer temperature of technogenic substrates, improving the conditions of growth localities. We established that on the dump the dominant moss species are dioecious with a high level of reproductive effort (sexual and sexless), with short ontogenesis and age of first reproduction, which provides the chance to produce the maximum number of progeny in the minimum period and to form a complete moss cover. The analysis of seasonal moss photosynthesis dynamics has demonstrated the adaptability of moss photosynthetic apparatus to contrasting climatic conditions and the ability to support the intensity of photosynthetic processes on a rather stable level during the vegetative period. Our research showed that bryophytes play an important role in productivity of plant cover on the post-technogenic territories of sulphur extraction. It was found that bryophytes play a role in accumulation of organic carbon and biogenic elements in the substrate of the sulphur extraction dump . Carrying out research of specific composition dynamics and species activity is the precondition for revealing the essence of the dynamic processes taking place in the structure of the bryophyte communities on devastated territories and the influence of these processes on the formation of vegetation on dump complexes.

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Linking Termite Feeding Preferences and Soil Physical Functioning in Southern-Indian Woodlands

Insects ◽

10.3390/insects10010004 ◽

2019 ◽

Vol 10 (1) ◽

pp. 4 ◽

Cited By ~ 5

Author(s):

Sougueh Cheik ◽

Rashmi Ramesh Shanbhag ◽

Ajay Harit ◽

Nicolas Bottinelli ◽

Raman Sukumar ◽

...

Keyword(s):

Hydraulic Conductivity ◽

Deciduous Forest ◽

Soil Surface ◽

Soil Bulk Density ◽

Water Infiltration ◽

Arid Environments ◽

Feeding Preferences ◽

Soil Hydraulic Conductivity ◽

Odontotermes Obesus ◽

Soil Hydraulic

Termites are undoubtedly amongst the most important soil macroinvertebrate decomposers in semi-arid environments in India. However, in this specific type of environment, the influence of termite foraging activity on soil functioning remains unexplored. Therefore, this study examines the link between the quality of litter and the functional impact of termite feeding preferences on soil properties and soil hydraulic conductivity in a deciduous forest in southern India. Different organic resources (elephant dung: “ED”, elephant grass: “EG”, acacia leaves: “AL” and layers of cardboard: “CB”) were applied on repacked soil cores. ED appeared to be the most attractive resource to Odontotermes obesus, leading to a larger amount of soil sheeting (i.e., the soil used by termites for covering the litter they consume), more numerous and larger holes in the ground and a lower soil bulk density. As a consequence, ED increased the soil hydraulic conductivity (4-fold) compared with the control soil. Thus, this study highlights that the more O. obesus prefers a substrate, the more this species impacts soil dynamics and water infiltration in the soil. This study also shows that ED can be used as an efficient substrate for accelerating the infiltration of water in southern-Indian soils, mainly through the production of galleries that are open on the soil surface, offering new perspectives on termite management in this environment.

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