scholarly journals Saturated hydraulic conductivity (Ks) of earth materials in a weathering profile over the Kuantan Basalt, Pahang, Malaysia

Warta Geologi ◽  
2021 ◽  
Vol 47 (2) ◽  
pp. 113-121
Author(s):  
John Kuna Raj
Keyword(s):  
Hydraulic Conductivity ◽  
Olivine Basalt ◽  
Saturated Hydraulic Conductivity ◽  
Weathering Profile ◽  
Rainfall Events ◽  
Soil Zone ◽  
The Earth ◽  
Clayey Silt ◽  
Zone Ii ◽  
Constant Head

Three broad morphological zones can be differentiated at the weathering profile; the top, 3.80 m thick, pedological soil (zone I with sub-zones IA, IB and IC) comprising soft to stiff, brown clays and the bottom bedrock (zone III) being an outcrop of vesicular olivine basalt. The intermediate zone II (saprock) is 1.12 m thick and consists of brown, very stiff, sandy clayey silt with many lateritic concretions. Laboratory constant head permeability tests show the saturated hydraulic conductivity (Ks) to vary with depth; sub-zone IB having a conductivity of 0.007 cm/hr, and sub-zone IC (saprolite), and zone II (saprock), having conductivities of 0.147, and 0.447, cm/hr, respectively. The conductivity values show no correlation with physical properties of the earth materials, but increase with increasing sand, gravel, and silt, contents. The conductivity values also decrease with increasing clay and colloid contents. The low hydraulic conductivity of sub-zone IB will lead to surface runoff and ponding over natural ground surfaces during rainfall events, though over disturbed ground surfaces, infiltration is anticipated in view of exposed saprolite and saprock earth materials with relatively high conductivity

scholarly journals Saturated Hydraulic Conductivity (Ks) Of Earth Materials In The Weathering Profile Over A Porphyritic Biotite Granite At The Kuala Lumpur - Karak Highway In Peninsular Malaysia

2021 ◽  
Vol 71 ◽  
pp. 1-11
Author(s):  
John Kuna Raj
Keyword(s):  
Hydraulic Conductivity ◽  
Correlation Coefficients ◽  
Biotite Granite ◽  
Saturated Hydraulic Conductivity ◽  
Silty Sand ◽  
Unit Weight ◽  
Kuala Lumpur ◽  
Weathering Profile ◽  
Clayey Sand ◽  
Zone Ii

Three broad zones can be differentiated within the weathering profile over porphyritic biotite granite at Km 31 of the Kuala Lumpur - Karak Highway. The top Zone I (pedological soil) is 12 m thick and comprises A, B and C soil horizons; the C horizon (saprolite) being a clayey sand with indistinct relict bedrock textures. The intermediate Zone II (saprock) is some 30 m thick and consists of silty sands that indistinctly to distinctly preserve the minerals, textures and structures of the original granite. Zone II can be differentiated into four sub-zones; the upper II A and II B sub-zones marked by an absence of core boulders, whilst the lower II C and II D sub-zones have some to many core-boulders. The bottom Zone III (bedrock), whose upper surface is marked by an unconfined groundwater table, is a continuous granite outcrop with effects of weathering along and between discontinuity planes. Constant head permeability tests show saturated hydraulic conductivity (Ks) to vary with depth and texture; clayey sand from saprolite having a conductivity of 0.2420 cm/hr and silty sand from sub-zone II B, a conductivity of 0.7464 cm/hr. Silty sands from sub-zone II D have saturated hydraulic conductivity values of 1.5313, and 1.9585, cm/hr, whilst a silty sand from sub-zone II C has a conductivity of 4.1131 cm/hr due to it being collected at a relict pegmatite pod. Regression analyses show variable trends with low to moderate correlation coefficients (R2 <0.600) for hydraulic conductivity versus index properties as clay and sand contents, but large correlation coefficients (R2 >0.820) for hydraulic conductivity versus physical properties as dry unit weight and void ratio.

Effects of skidding on forest soil infiltration in west-central Alberta

2000 ◽  
Vol 80 (4) ◽  
pp. 617-624 ◽  
Author(s):  
A. D. Startsev ◽  
D. H. McNabb
Keyword(s):  
Hydraulic Conductivity ◽  
Boreal Forests ◽  
Soil Water Potential ◽  
Infiltration Rate ◽  
Forest Harvesting ◽  
Saturated Hydraulic Conductivity ◽  
Soil Freezing ◽  
Surface Erosion ◽  
Soil Infiltration ◽  
Constant Head

Soil compaction during forest harvesting generally reduces macropore space, which reduces infiltration and increases the potential for surface erosion and waterlogging. Hydrological effects of 3, 7 and 12 skidding cycles and their persistence were evaluated for 3 yr at 14 sites, which represented a range of soil texture and compaction conditions in the foothills and boreal forests of Alberta. Saturated hydraulic conductivity (HC) was determined using a constant head method on soil cores collected from 5- and 10-cm depths; unconfined infiltration rate of the surface soil (IR) was measured in situ with tension infiltrometers at near saturation. A significant (P < 0.05) increase in bulk density during skidding caused a significant reduction in both HC and IR after the first three cycles at eight sites where soil water potential at the time of skidding was higher than −15 kPa; the decrease at the other sites was not significant. Additional traffic, up to 12 cycles, did not cause a further significant decrease in HC or IR. The infiltration rate of soil compacted by three skidding cycles showed a recovery trend. However, in more intensively trafficked soils, compaction effects on infiltration remained significant for at least 3 yr, which was possibly attributed to heavy snowpacks preventing soil freezing at lower depths. Key words: Saturated hydraulic conductivity, unconfined infiltration rate, tension infiltrometers, skidders, boreal forest, Alberta

COMPARISON OF METHODS FOR DETERMINING SATURATED HYDRAULIC CONDUCTIVITY AND DRAINABLE POROSITY OF TWO SOUTHERN ALBERTA SOILS

1986 ◽  
Vol 66 (2) ◽  
pp. 249-259 ◽  
Author(s):  
G. D. BUCKLAND ◽  
D. B. HARKER ◽  
T. G. SOMMERFELDT
Keyword(s):  
Soil Moisture ◽  
Hydraulic Conductivity ◽  
Characteristic Curve ◽  
Subsurface Drainage ◽  
Saturated Hydraulic Conductivity ◽  
Drainage Design ◽  
Moisture Characteristic ◽  
Constant Head ◽  
Subsurface Drains ◽  
Drainable Porosity

Saturated hydraulic conductivity (Ks) and drainable porosity (f) determined by different methods and for different depths were compared with those determined from the performance of drainage systems installed at two locations. These comparisons were made to determine which methods are suitable for use in subsurface drainage design. Auger hole and constant-head well permeameter Ks were 140 and 110%, respectively, of Ks determined from subsurface drains. Agreement of horizontal or vertical Ks, from in situ falling-head permeameters; to other methods was satisfactory providing sample numbers were large. Ks by Tempe cells was only 3–10% of drain Ks and in one instance was significantly lower than Ks determined by all other methods. At one site a profile-averaged value of f determined from the soil moisture characteristic curve (0–5 kPa) of semidisturbed cores agreed with that determined from drainage trials. At the other site, a satisfactory value of f was found only when the zone in which the water table fluctuated was considered. Results indicate that Ks determined by the auger hole and constant-head well permeameter methods, and f determined from the soil moisture characteristic curve of semidisturbed cores, are sufficiently reliable and practical for subsurface drainage design. Key words: Subsurface drainage, hydraulic conductivity, drainable porosity

Subsoil hydraulic conductivity estimates for the Lower Macquarie Valley

Soil Research ◽  
1996 ◽  
Vol 34 (2) ◽  
pp. 213 ◽  
Author(s):  
TL Bird ◽  
TM Willis ◽  
GJ Melville
Keyword(s):  
Hydraulic Conductivity ◽  
Irrigation Water ◽  
Clay Content ◽  
Strong Relationship ◽  
Saturated Hydraulic Conductivity ◽  
Deep Drainage ◽  
Soil Variation ◽  
Constant Head ◽  
Semi Empirical ◽  
Soil Groups

Field saturated hydraulic conductivity was measured in situ, at two depths in the B horizon, on irrigated soils in the Lower Macquarie Valley. Measurements were made with constant head well permeameters, using the single-head method, and water of moderate sodicity and high salinity. The hydraulic conductivity data were log-normally distributed for all soil groups and there were significant differences between some of these soil groups in mean hydraulic conductivity. Three soils exhibited significant differences in mean hydraulic conductivity between depths. Hydraulic conductivity measurements ranged up to 3 orders of magnitude within a soil. Variation in hydraulic conductivity estimates, both between and within soil groups, confirmed the variation observed in previous predictions of deep drainage, which were obtained using a semi-empirical model. A cluster analysis on hydraulic conductivity indicated that similar morphological soil properties did not necessarily reflect similar hydrologic properties. There was a strong relationship between hydraulic conductivity and exchangeable sodium percentage (ESP), hydraulic conductivity and clay content, and ESP and clay content. A model was developed to predict field saturated hydraulic conductivity from ESP and clay content data. Hydraulic conductivity measured in this study may not have been representative of percolation rates which would occur with low salinity irrigation water, but can be used to assess the risk of recharge from irrigation on different soils in the lower Macquarie Valley. Shallow watertables may potentially develop when the application of irrigation water greatly exceeds crop water requirements. Quantification of groundwater recharge will allow the likelihood of shallow watertable development in the Lower Macquarie Valley to be assessed.

scholarly journals A modification of the constant-head permeameter to measure saturated hydraulic conductivity of highly permeable media

MethodsX ◽  
2017 ◽  
Vol 4 ◽  
pp. 134-142 ◽  
Author(s):  
Jelmer J. Nijp ◽  
Klaas Metselaar ◽  
Juul Limpens ◽  
Harm P.A. Gooren ◽  
Sjoerd E.A.T.M. van der Zee
Keyword(s):  
Hydraulic Conductivity ◽  
Saturated Hydraulic Conductivity ◽  
Permeable Media ◽  
Constant Head

Application of the steady-state principle of constant-head well permeameter to indirect subsurface drip irrigation

2009 ◽  
Vol 89 (5) ◽  
pp. 671-676 ◽  
Author(s):  
Z Weixia ◽  
C Huanjie ◽  
Z Zhenhua ◽  
S Zhijie
Keyword(s):  
Steady State ◽  
Hydraulic Conductivity ◽  
Drip Irrigation ◽  
Discharge Rate ◽  
Saturated Hydraulic Conductivity ◽  
Subsurface Drip Irrigation ◽  
Equilibration Time ◽  
Constant Head ◽  
Subsurface Drip ◽  
Emitter Discharge

Indirect subsurface drip irrigation (ISDI) is a method of increasing the irrigation water use efficiency of drip irrigation without the need to bury irrigation tubes and wet the soil surface. A major problem of ISDI is the mismatch between emitter discharge rate and water-conducting device dimension, which will result in over-filling of application water. In this paper, we propose to use the steady-state principle of constant-head well permeameter (CHWP) to quantify the relationship between emitter discharge rate and water-conducting device dimension for ISDI. CHWP tests and ISDI tests were carried out in a 300 m2 winter wheat fallow to verify its feasibility. The steady-state characteristic of these two methods was also studied using long-term infiltration. Results indicate that the equilibration time (110 min) in the ISDI tests was greater than that in the CHWP tests (30 min). The steady ponded depth in ISDI had a smaller variation than the steady water discharge rate in the CHWP. When using the steady-state principle of CHWP to design ISDI systems, there was significant linear correlation between predicted and measured ponded depth values (R2 = 0.8379). The soil field-saturated hydraulic conductivity calculated by these two tests was approximately equal. These results demonstrate that the steady-state principle of CHWP could be used to select appropriate irrigation systems for ISDI, and ISDI provides another technique to obtain the field-saturated hydraulic conductivity. Key words: Constant-head well permeameter, field-saturated hydraulic conductivity, indirect subsurface drip irrigation, steady-state

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