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Previous in-situ measurements of soil-like materials on the surface of Mars, in particular during the on-going Mars Exploration Rover missions, have shown complex relationships between composition, exposure to the surface environment, texture, and local rocks. In particular, a diversity in both compositional and physical properties could be established that is interpreted to be diagnostic of the complex geologic history of the martian surface layer. Physical and chemical properties vary laterally and vertically, providing insight into the composition of rocks from which soils derive, and environmental conditions that led to soil formation. They are central to understanding whether habitable environments existed on Mars in the distant past. An instrument the Mole for Soil Compositional Studies and Sampling (MOCSS) - is proposed to allow repeated access to subsurface regolith on Mars to depths of up to 1.5 meters for in-situ measurements of elemental composition and of physical and thermophysical properties, as well as for subsurface sample acquisition. MOCSS is based on the compact PLUTO (PLanetary Underground TOol) Mole system developed for the Beagle 2 lander and incorporates a small X-ray fluorescence spectrometer within the Mole which is a new development. Overall MOCSS mass is approximately 1.4 kilograms. Taken together, the MOCSS science data support to decipher the geologic history at the landing site as compositional and textural stratigraphy if they exist - can be detected at a number of places if the MOCSS were accommodated on a rover such as MSL. Based on uncovered stratigraphy, the regional sequence of depositional and erosional styles can be constrained which has an impact on understanding the ancient history of the Martian near-surface layer, considering estimates of Mars soil production rates of 0.5... 1.0 meters per billion years on the one hand and Mole subsurface access capability of approximately 1.5 meters. An overview of the MOCSS, XRS instrument accomodation and the impact that these instruments have on Mars science is discussed.

Studying Lunar Orbiter photographs of boulder tracks left on lunar surface to determine soil cohesion and angle of internal friction

Predictive procedures for developing soil hydrologic properties (i.e., relationships of soil water pressure and hydraulic conductivity to soil water content) are presented. Three models of the soil water pressure-water content relationship and one model of the hydraulic conductivity-water content relationship are discussed. Input requirements for the models are indicated, and computational procedures are outlined. Computed hydrologic properties for Keith silt loam, a soil typer near Colby, Kansas, on which the 1978 Agricultural Soil Moisture Experiment was conducted, are presented. A comparison of computed results with experimental data in the dry range shows that analytical models utilizing a few basic hydrophysical parameters can produce satisfactory data for large-scale applications.

This paper presents study of the stabilization of natural soil with lime. Firstly, Soil samples from Madaya Township are collected and several laboratory tests are carried out to determine the characteristics and engineering properties of the studied soil. Then experimental tests have been conducted for the determination of Atterberg limits and California Bearing Ratio CBR values. The studied soil contains more than 50 of silt clay fraction. So, the studied soil is stabilized with lime contents selected as 5 and 10 by weight of natural soil at maximum dry density. When soil samples are mixed with lime, the values of liquid limit, plasticity index and CBR values are changed. These changes are decreased in swelling and shrinking potential of the soil, decreased in the settlement of the pavements, increase in workability and increase in the bearing capacity of the soils. In this study, the CBR values of soil lime mixtures are 71.4 and 64.4 higher than that of studied soil. It can be seen that the CBR value of lime 5 is greater than lime 10 and natural soil. So, soil lime mixture with lime 5 content is suiTablefor soil stabilization of the street, road and highway. By Nyein Nyein Thant | Tin Yadanar Kyaw "Study on the Properties of Natural Soil Stabilized with Various Percentages of Lime Contents" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27871.pdf Paper URL https://www.ijtsrd.com/engineering/electrical-engineering/27871/study-on-the-properties-of-natural-soil-stabilized-with-various-percentages-of-lime-contents/nyein-nyein-thant

Paper Mill is a wood based power plant which generates a huge amount of fly ash. The application of fly ash in degraded land may reduce the problem of disposal to some extent. A field study was carried out on a sandy loam soil at the KVK farm Janjgir Champa, Chhattisgarh to study 

Phosphorus (P) sorption influences P requirement of Nigerian soils. Four Inceptisols in Benue state were therefore used to examine the influence of soil properties on sorption indices and yield of soybean. Soil inorganic P was fractionated using standard procedures. Sorption characteristics were determined in 0.01 M CaCl2 solutions of various P concentrations. For each soil, the amounts of P that gave 0.025, 0.05, 0.075, 0.100, 0.125, 0.150, 0.175, 0.200, 0.225, 0.250 mg/kg solution concentration and the buffering capacity were estimated from adsorption curves. In the greenhouse, 4 kg of soil from each location was placed in plastic pots. Amount of P estimated from sorption study was added as KH2PO4. The treatments were laid out in Randomized Complete Block Design (RCBD) and soybean seed variety (TGx 1448-2E) was planted and observed to maturity. At harvest, the shoot was dried, weighed, milled and digested in a 4:1 HNO3:HClO4 mixture and analyzed for P. Optimum solution P concentration (SPC) was determined for each soil in relation to yield. The P adsorption capacities (K) of the soils related significantly to P in biomass (r=0.661). High grain yield (t/ha) was obtained at 0.025 mg P/kg SPC in Abeda-Mbadyul (8.5) and Otobi-Akpa (12.5) while 5.4 t/ha was obtained in Tor-donga and 4.1 t/hain Odobaat 0.10 mg P/kg SPC in the green house experiment. Slightly higher grain yield was obtained at Otobi (6.4t/ha) in the field trial than the estimated SPC values. Buffering capacities of soils varied and related significantly with seed weight (r= 0.605) and P in biomass (r=-0.667). Consequently, Odoba would require highest P fertilizer application (604.84 Kg P/ha), Tor-Donga (112.31), Abeda-Mbadyul (105.93) and Otobi (33.18) 

Phosphorus (P) sorption influences P requirement of Nigerian soils. Four Inceptisols in Benue state were therefore used to examine the influence of soil properties on sorption indices and yield of soybean. Soil inorganic P was fractionated using standard procedures. Sorption characteristics were determined in 0.01 M CaCl2 solutions of various P concentrations. For each soil, the amounts of P that gave 0.025, 0.05, 0.075, 0.100, 0.125, 0.150, 0.175, 0.200, 0.225, 0.250 mg/kg solution concentration and the buffering capacity were estimated from adsorption curves. In the greenhouse, 4 kg of soil from each location was placed in plastic pots. Amount of P estimated from sorption study was added as KH2PO4. The treatments were laid out in Randomized Complete Block Design (RCBD) and soybean seed variety (TGx 1448-2E) was planted and observed to maturity. At harvest, the shoot was dried, weighed, milled and digested in a 4:1 HNO3:HClO4 mixture and analyzed for P. Optimum solution P concentration (SPC) was determined for each soil in relation to yield. The P adsorption capacities (K) of the soils related significantly to P in biomass (r=0.661). High grain yield (t/ha) was obtained at 0.025 mg P/kg SPC in Abeda-Mbadyul (8.5) and Otobi-Akpa (12.5) while 5.4 t/ha was obtained in Tor-donga and 4.1 t/hain Odobaat 0.10 mg P/kg SPC in the green house experiment. Slightly higher grain yield was obtained at Otobi (6.4t/ha) in the field trial than the estimated SPC values. Buffering capacities of soils varied and related significantly with seed weight (r= 0.605) and P in biomass (r=-0.667). Consequently, Odoba would require highest P fertilizer application (604.84 Kg P/ha), Tor-Donga (112.31), Abeda-Mbadyul (105.93) and Otobi (33.18) 

Phosphorus (P) sorption influences P requirement of Nigerian soils. Four Inceptisols in Benue state were therefore used to examine the influence of soil properties on sorption indices and yield of soybean. Soil inorganic P was fractionated using standard procedures. Sorption characteristics were determined in 0.01 M CaCl2 solutions of various P concentrations. For each soil, the amounts of P that gave 0.025, 0.05, 0.075, 0.100, 0.125, 0.150, 0.175, 0.200, 0.225, 0.250 mg/kg solution concentration and the buffering capacity were estimated from adsorption curves. In the greenhouse, 4 kg of soil from each location was placed in plastic pots. Amount of P estimated from sorption study was added as KH2PO4. The treatments were laid out in Randomized Complete Block Design (RCBD) and soybean seed variety (TGx 1448-2E) was planted and observed to maturity. At harvest, the shoot was dried, weighed, milled and digested in a 4:1 HNO3:HClO4 mixture and analyzed for P. Optimum solution P concentration (SPC) was determined for each soil in relation to yield. The P adsorption capacities (K) of the soils related significantly to P in biomass (r=0.661). High grain yield (t/ha) was obtained at 0.025 mg P/kg SPC in Abeda-Mbadyul (8.5) and Otobi-Akpa (12.5) while 5.4 t/ha was obtained in Tor-donga and 4.1 t/hain Odobaat 0.10 mg P/kg SPC in the green house experiment. Slightly higher grain yield was obtained at Otobi (6.4t/ha) in the field trial than the estimated SPC values. Buffering capacities of soils varied and related significantly with seed weight (r= 0.605) and P in biomass (r=-0.667). Consequently, Odoba would require highest P fertilizer application (604.84 Kg P/ha), Tor-Donga (112.31), Abeda-Mbadyul (105.93) and Otobi (33.18) 

The main objectives of this study were to evaluate the effect of animal manures combinations and humic acid on some soil biochemical properties. The laboratory incubation experiment was conducted using a completely randomized design with three replicates. The animal manures included chicken manure (ChM) and cow manure (CoM). The treatments of humic acid (HA), chicken manure (ChM) and cow manure (CoM) were applied on clay soil at a rate of 10 t. ha-1. The treatments used were: Control (T1), HA (T2), HA + ChM (T3) and HA + CoM (T4). The soil samples were incubated for 15, 30, 45 and 60 days at 28 ˚C and was analyzed for soil pH, the electrical conductivity (EC), total nitrogen, available phosphorus, potassium content, soil organic carbon percentages (SOC) and soil respiration (CO2). In general, the results showed a significant difference between all treatments and the control. Also, the applications of treatments have lowered the soil pH and significant increase in EC was observed as days of incubation. While, the N, P, K, SOC and soil respiration (CO2) were significant increased and reached its peak at 45 days of incubation and decreased thereafter with time. The results showed that applications of organic matter had significant effect on soil biochemical properties and treatment 4 T4 (HA+ CoM) showed a significant superiority compare with other treatments.

The study was conducted at Abakaliki to determine the changes in selected soil physical properties and maize yields as affected by animal wastes application in Abakaliki southeastern Nigeria in 2014 and 2015 cropping seasons. The experiment was laid out in Randomized Complete Block Design with four treatment replicated five times. The treatments were poultry droppings at 5 tha-1 (PD), cow dung at 5 tha-1 (CD), mixture of PD + CD at 5 tha-1 and control (C) – non application of amendment. Bulk density, total porosity, moisture content, aggregate stability and mean weight diameter were determine in the laboratory using appropriate procedure while plant height, leaf area index and grain yield were also, measured in the field using recommended methods. The results showed positive changes in selected soil physical properties and maize yield in the two cropping seasons with the application of animal wastes. Also, improvement in soil physical properties and maize yields were higher in the second cropping season when compared to the first cropping season. Poultry dropping is recommended for farmers to use as fertilizer in maize production because plots treated with poultry droppings recorded the highest maize grain yield in the two cropping season than other treatments.

The research was embarked upon to assess the variability in some physico-chemical properties of soil along a toposequence in Alvan Ikoku Federal College of Education, Owerri, Imo State. Soil samples were collected from two different depths, 0-15 cm and 15-30 cm, at each topographic unit, namely, upper slope, mid slope and bottom slope.              A total of 12 samples were used for the study. The, samples collected were air-dried, crushed and sieved in a 2 mm sieve preparatory to laboratory analysis. Means and coefficient of variation were used as the statistical tools. The results show that the physico-chemical properties of soil along the toposequence varied from low to high variation with the coefficient variation ranging from 1.05 % to 77.5 %. Sand fractions increases with depth, silt contents increases with decrease in slope and clay content increases down the slope and depth. The silt/clay ratio was low in all pedons. Soil pH was acidic in all the pedons. Percent organic carbon decreased with depth and increased from upper to bottom slopes. The results of this work have showed that there are changes in some physico-chemical properties of soil along a toposequence in A. I. F. C. E, Owerri.

Soil Stabilization usually enhances performance properties of soil. This can foster waste to wealth policy in country like Nigeria. The aim of this study is to assess performance properties of a stabilized lateritic soil with a view to obtain a cheap and more effective additive. Soil samples were collected from the study area and subjected to Compaction and California Bearing Ratio (CBR) laboratory tests with the addition of 2%, 4%, 6%, 8% and 10% Rice Husk Ash (RHA) and Egg Shell Ash (ESA). Results showed that MDD, OMC and CBR values varied from 1575Kg/m3 to 1930Kg/m3, 7.55% to 18.50% and 20% to 131% respectively for sample A. And 1566Kg/m3 to 1896Kg/m3, 7.53% to 16.90% and 16% to 98% respectively for sample B. The MDD values decrease with increase in the additives contents due to the replacement of soil by the additives in the mixture, coating of the soil by additives which resulted in large particles with larger voids and density; and addition of the additives which decreased the quality of free silt, clay fraction and coarse materials with large surface areas formed. OMC values also increase as the additives increase, though, that of RHA increases more than that of ESA. This is due to the increase in additives which resulted to increase in the amount of water required in the system to adequately lubricate all the particles in the mixture equally increase. Generally, CBR values also increase with increase in the additives contents. This could be attributed to gradual formation of cementitious compound between the additives and Calcium Hydroxide (Ca(OH)2) present in the soil, thus increase in coarse particles of the soil through cementation.

ABSTRACT Some soils in Kabba College of Agriculture, Kogi State, southern guinea savannah zone of Nigeria, were assessed to ascertain the levels of degradation of soil properties. The rigid grid soil survey method was used to identify seven soil units. Soils were sampled at 0-20 cm and 20-40 cm soil depth and analyzed for physical and chemical properties using standard methods. Levels of degradation were obtained by comparing laboratory data with the standard land/soil requirement (indicators/criteria) for grouping lands into different degradation classes of 1 to 4 (non to slightly, moderately, highly, and very highly degraded). Results showed that units D (soghum) and E (citrus) were very highly degraded (Class 4) of exchangeable potassium; units C (yam), D and E were highly degraded (Class 3) of organic matter. Other units were moderately degraded (Class 2) of base saturation, bulk density and total nitrogen. There was no degradation of available phosphorus and exchangeable sodium percentage in all the units. Physical and chemical degradation took place in the study area with respect to bulk density, base saturation, total nitrogen, potassium, and organic matter. Sustainable management practices that will promote good bulk density and organic matter accumulation should be encouraged.

Theoretically, crop yields, soil properties and factors of soil genesis (state factors) are interrelated as a multivariate system. To test this broad concept, 97 soils were collected in California along a moisture transect reaching from the desert to the perhumid region. Parent rock, exposure, slope and natural vegetation (pines, grasslands) were rigidly controlled. The mathematical model was based on linear regression analysis involving observational variables as well as principal components with and wHhout varimax rotation. The variability of soil properlies, especially those related to organic matter, could be accounted for in high degree by the present-day soil forming factors, especially climate and natural vegetation. The old idea that N and C are linked by common microbial genesis could not be confirmed as the two elements behaved differentially. Nitrogen was but moderately related to climate and barely so to flora, but strongly to parent material and clay mineralogy. Carbon, on the other hand, responded strongly to precipitation and temperature and markedly to plant species, which was especially expressive in the bchavior of C/N. Clay mineralogy correlated with climate and parent material, and, at a given climate, also with floristic differentiation. Correlation coefficients (r) among the soil properties ranged between near-zero and near the maximum of 1.00. The coefficients of carbon with the other soil properties were governed by their dependencies on precipitation. It takes but a few decades or centuries to establish high r values between such pairs as carbon and acidity. Soil fertility was ascertained in a large-scale standardized pot test experiment. The yields variations still reflected the state factors of soil origin. Degree of correlation of yields with multiple soil properties tended to depend on the genetic ordination of soil samples; the more heterogeneous the soil group as to dichotomous factors such as rocks and flora, the less was the multiple coefficient of correlation.

Theoretically, crop yields, soil properties and factors of soil genesis (state factors) are interrelated as a multivariate system. To test this broad concept, 97 soils were collected in California along a moisture transect reaching from the desert to the perhumid region. Parent rock, exposure, slope and natural vegetation (pines, grasslands) were rigidly controlled. The mathematical model was based on linear regression analysis involving observational variables as well as principal components with and wHhout varimax rotation. The variability of soil properlies, especially those related to organic matter, could be accounted for in high degree by the present-day soil forming factors, especially climate and natural vegetation. The old idea that N and C are linked by common microbial genesis could not be confirmed as the two elements behaved differentially. Nitrogen was but moderately related to climate and barely so to flora, but strongly to parent material and clay mineralogy. Carbon, on the other hand, responded strongly to precipitation and temperature and markedly to plant species, which was especially expressive in the bchavior of C/N. Clay mineralogy correlated with climate and parent material, and, at a given climate, also with floristic differentiation. Correlation coefficients (r) among the soil properties ranged between near-zero and near the maximum of 1.00. The coefficients of carbon with the other soil properties were governed by their dependencies on precipitation. It takes but a few decades or centuries to establish high r values between such pairs as carbon and acidity. Soil fertility was ascertained in a large-scale standardized pot test experiment. The yields variations still reflected the state factors of soil origin. Degree of correlation of yields with multiple soil properties tended to depend on the genetic ordination of soil samples; the more heterogeneous the soil group as to dichotomous factors such as rocks and flora, the less was the multiple coefficient of correlation.

Black cotton soils are among a group of soils termed as problematic soils. These soils have undesirable characteristics in relation to construction works and therefore need some form of improvement when encountered in construction projects. Techniques for improvement of black cotton soils include replacement, moisture control or adding a stabilizer. Cement and/or lime has been commonly used in soil stabilization for ages. However, due to the associated cost, required quality control and the need to utilize waste materials in construction, new stabilizing materials are emerging. This paper presents a study on application of quarry dust for improving properties of black cotton soil in Mbeya region, Tanzania. The targeted improvement was to achieve minimum acceptable characteristics for road subgrade as per Tanzania standards. It was determined that 40% by weight of quarry dust added to the black cotton soil was able to improve the characteristics by increasing CBR value from 3.8 to 15.7 and reducing PI from 32% to 15%. It will be worthy studying the cost implication of the suggested improvement in relation to other techniques before application of the study findings.  

Black cotton soils are among a group of soils termed as problematic soils. These soils have undesirable characteristics in relation to construction works and therefore need some form of improvement when encountered in construction projects. Techniques for improvement of black cotton soils include replacement, moisture control or adding a stabilizer. Cement and/or lime has been commonly used in soil stabilization for ages. However, due to the associated cost, required quality control and the need to utilize waste materials in construction, new stabilizing materials are emerging. This paper presents a study on application of quarry dust for improving properties of black cotton soil in Mbeya region, Tanzania. The targeted improvement was to achieve minimum acceptable characteristics for road subgrade as per Tanzania standards. It was determined that 40% by weight of quarry dust added to the black cotton soil was able to improve the characteristics by increasing CBR value from 3.8 to 15.7 and reducing PI from 32% to 15%. It will be worthy studying the cost implication of the suggested improvement in relation to other techniques before application of the study findings.  

The report describes measurements of the electromagnetic parameters of soil samples in the VHF/UHF range the purpose of which was to accumulate basic data on the properties that limit subsurface target detection by EM methods. A section of coaxial waveguide filled with soil is treated as a length of lossy transmission line. Classical transmission-line theory is used in determining the complex propagation constant of the soil sample from measurements on the electrical phase and the VSWR. These data are fed into classical equations which were programmed for computer solution. Also included in the report for completeness and comparison are the results of two other techniques for measuring the real part of the complex propagation constant. The first of these techniques requires electrical phase and VSWR measurements and the solution is obtained graphically. The second technique requires the measurement of a power ratio under matched conditions of the line under test.

This volume was digitized and made accessible online due to deterioration of the original print copy.

Cone index (CI) has been used successfully by the U.S. Army Engineer Waterways Experiment Station (WES) as a descriptor of soil strength in establishing empirical soil-vehicle relations for predicting the performance of ground-crawling vehicles. CI is a measure of the resistance of the soil to the penetration of a right-circular cone. CI is measured in pounds per square inch, but it is considered an undimensioned index for obvious reasons. Recent developments in analytical modeling of vehicle performance require that the soil be described in terms of its fundamental properties such as angle of internal friction, cohesion, stiffness, density, etc. In order to utilize the larger CI data base and establish correspondence between the empirical studies and theoretical mobility models, it was necessary to correlate CI with the engineering properties of soil. This paper describes the development of a mathematical model that treats the cone penetration process as expansion of a series of spherical cavities, simulating the geometry of the cone, in an elastic-plastic isotropic medium. The stresses required to expand these cavities are integrated over the surface area of the cone in order to determine the forces resisting the penetration of the cone, in terms of the fundamental engineering properties of soil. Analytical predictions are made for the standard WES cone penetrometer, which is a 30-degree, right-circular cone of 0.5 sq in. base area, and the results are compared with experimental data for various types of soil. The results achieved indicate good agreement between CI and basic engineering soil properties.

This article is from SpringerPlus , volume 2 . Abstract Effects of cropping practices on soil properties viz. particle size distribution, pH, bulk density (BD), field capacity (FC, -33 kPa), permanent wilting point (PWP, -1500 kPa), available water capacity (AWC) and soil organic carbon (SOC) were assessed. The pedotransfer functions (PTFs) were developed for saturated hydraulic conductivity (Ks), water retention at FC and PWP of soils for different sites under major cropping system in a canal irrigated area. The results revealed that the soils are mainly composed of sand and clay with the clay contents ranging from 29.6 to 48.8%, BD of 1.44-1.72 Mg m-3, and 0.34 to 0.95% SOC. The Ks decreased, and water retention at FC, PWP and AWC increased significantly with soil depth due to greater clay contents in lower soil depths. The PTFs were best represented as the power functions for prediction of Ks with clay content as predictor variable; whereas the PTFs for water retention at FC and PWP were better represented as the exponential functions. SOC content was higher under rice-sugarcane crop rotation compared to other systems. SOC storage in the surface layer was higher in rice-sugarcane rotation (18.90-20.53 Mg ha-1) than other sites. The developed PTFs would be very useful in soil and water management strategies for the study area or elsewhere having similar soil and cropping practices. The information on SOC storage in the Kuanria region would help for better soil and crop planning in future.

This study experimentally explored the conditions, equipment, and methodology necessary for the acoustic detection of small leaks of jet fuel (JP4) from underground storage tank (UST) systems. The study indicates that acoustic leak detection of very small leaks is feasible. In general, significant JP4 fuel leaks which occur across a 5 PSI (pounds per square inch) or greater pressure drop are acoustically active and can be detected with proper sensors and proper placement of sensors. The primary source of leak noise is turbulent flow through the leak orifice. At lower pressures, the leak flow becomes laminar, and the leak becomes virtually silent. With direct transducer contact on the pipe or tank wall and sufficient system pressure, leaks smaller than 0.1 GPH (gallons per hour) can be detected. Larger leaks can be detected through short distances in soil. However, sand, which is the most commonly used fill material for UST systems, provides significant acoustic attenuation. Consequently, waveguides must be used when monitoring distances exceeding about 1 foot of travel through sand. Sand acts to reduce background noise levels, providing an ideal environment for acoustic leak detection using sensors mounted directly on the pipe or tank wall.

The dielectric constant and the voltage absorption length was measured for four Apollo 17 soil samples (73241, 74220, 75061, 76501) and for two Apollo 17 rock samples (76315 and 79135) at 450 MHz frequency. The dielectric constant and absorption length measurements made on the lunar samples are reviewed and related to the transition element concentration in these samples. The significance of the laboratory measurements for radar observations is discussed.

Accurate soil models are required for numerical simulations of land landings for the Orion Crew Exploration Vehicle (CEV). This report provides constitutive material models for two soil conditions at Kennedy Space Center (KSC) and four conditions of Mason Sand. The Mason Sand is the test sand for LaRC s drop tests and swing tests of the Orion. The soil models are based on mechanical and compressive behavior observed during geotechnical laboratory testing of remolded soil samples. The test specimens were reconstituted to measured in situ density and moisture content. Tests included: triaxial compression, hydrostatic compression, and uniaxial strain. A fit to the triaxial test results defines the strength envelope. Hydrostatic and uniaxial tests define the compressibility. The constitutive properties are presented in the format of LSDYNA Material Model 5: Soil and Foam. However, the laboratory test data provided can be used to construct other material models. The soil models are intended to be specific to the soil conditions they were tested at. The two KSC models represent two conditions at KSC: low density dry sand and high density in-situ moisture sand. The Mason Sand model was tested at four conditions which encompass measured conditions at LaRC s drop test site.

Computer codes used in the solution of free-field ground shock problems are based on mathematically defined constitutive models. Quantitative input for these constitutive models is primarily based on laboratory test data, but extensive analysis and numerous assumptions are required to convert these data to a form suitable for actual code input. This report presents a detailed illustration of the analyses involved in deriving the soil constitutive properties required for a specific code formulation using laboratory test data from just one stratum of a single site. Data are available from static and dynamic uniaxial strain and triaxial shear tests; code property requirements are for mathematical expressions relating mean pressure to volumetric strain, Poisson's ratio to mean pressure, and a plastic yield criterion to mean pressure. The illustration indicates that progress is being made in developing mathematical constitutive models that are realistic in terms of actual physical behavior, but that if many of the assumptions presently being made in soil property analyses are to be eliminated, additional soil tests and measurements must be developed.

The population density of enchytraeid worms (Oligochaeta) was monitored on a red earth (Oxic Paleustalf) under cropping in Wagga Wagga, N.S.W. Physical and chemical properties of their casts were compared with those of the bulk soil and soil sampled adjacent to the permanent fenceline. In the autumn and winter period, the worm population was active close to the surface and the highest population (2037 per m2) was detected in the direct drilled/stubble burnt treatment. However, this was considerably lower than those reported elsewhere in temperate regions. Worm casts were composite in nature, predominately of 210-500 µm in diameter which were comprised of smaller spherical subunits (50-100 µm). The casts were found to be significantly more water stable and higher in total nitrogen than aggregates of the same size range separated from the bulk soil. Porosity of the casts was dominated by spaces between the subunits which were composed of very densely packed clay/silt size particles. Evidence from SEM (scanning electron microscope) suggests that the high stability was due to the presence of cements.

Previous in-situ measurements of soil-like materials on the surface of Mars, in particular during the on-going Mars Exploration Rover missions, have shown complex relationships between composition, exposure to the surface environment, texture, and local rocks. In particular, a diversity in both compositional and physical properties could be established that is interpreted to be diagnostic of the complex geologic history of the martian surface layer. Physical and chemical properties vary laterally and vertically, providing insight into the composition of rocks from which soils derive, and environmental conditions that led to soil formation. They are central to understanding whether habitable environments existed on Mars in the distant past. An instrument the Mole for Soil Compositional Studies and Sampling (MOCSS) - is proposed to allow repeated access to subsurface regolith on Mars to depths of up to 1.5 meters for in-situ measurements of elemental composition and of physical and thermophysical properties, as well as for subsurface sample acquisition. MOCSS is based on the compact PLUTO (PLanetary Underground TOol) Mole system developed for the Beagle 2 lander and incorporates a small X-ray fluorescence spectrometer within the Mole which is a new development. Overall MOCSS mass is approximately 1.4 kilograms. Taken together, the MOCSS science data support to decipher the geologic history at the landing site as compositional and textural stratigraphy if they exist - can be detected at a number of places if the MOCSS were accommodated on a rover such as MSL. Based on uncovered stratigraphy, the regional sequence of depositional and erosional styles can be constrained which has an impact on understanding the ancient history of the Martian near-surface layer, considering estimates of Mars soil production rates of 0.5... 1.0 meters per billion years on the one hand and Mole subsurface access capability of approximately 1.5 meters. An overview of the MOCSS, XRS instrument accomodation and the impact that these instruments have on Mars science is discussed.

Improvement Of Sandy Soil Properties By Using Bentonite

Improvement Of Sandy Soil Properties By Using Bentonite

Utilization Waste Granulated Blast Furnace Slag To Improve The Properties Of Polluted Soil With Crude Oil

Soil organic carbon (SOC) plays an important role in soil fertility and is of paramount importance for its contributions to mitigation and adaptation to climate change. The present study was undertaken to estimate the SOC stock and soil properties in important plantations of the Southern zone in Tamil Nadu. Four different species were selected for the study viz, Eucalyptus, Casuarina, Melia and Teak. In all the plantations selected for estimation of biomass, composite soil samples were collected at three different depths; i.e., 0-15, 15- 30 and 30-45 cm. The soil samples were analysed for the carbon stock and various properties such as pH, Electrical conductivity, Organic carbon, Available N, Available P, Available K. Among Eucalyptus plantations, clonal plantation of >6 years sequestered the highest amount of soil carbon (19.8 Mg ha-1) at 30 cm depth. SOC stock was maximum in Casuarina plantation of > 5 years (23.3 Mg ha-1). Among the different Melia plantations, maximum SOC stock was observed in Melia plantation of 5 to7 years old (15.6 Mg ha-1), and in Teak plantations, SOC stock was highest in plantations of > 15 years old (22.1 Mg ha-1). The soil pH and Electrical conductivity significantly differed among the plantations and decreased with an increase in the age of plantation. Nitrogen availability was highest (303.98 kg ha-1 ) in >5 years of Casuarina clonal plantation at 0-15 cm depth. Among the plantations the available potassium was high in surface soils (0-15 cm) of >5 years Casuarina clonal plantation (329.50 kg ha-1). The data generated in the present study would provide valuable information on the scope of afforestation and reforestation projects for sustaining the livelihoods of the farming community and also will encourage them to contribute to mitigating global carbon emissions and expanding forest and tree cover.

A standardized global data set of soil horizon thicknesses and textures (particle size distributions) was compiled. This data set will be used by the improved ground hydrology parameterization designed for the Goddard Institute for Space Studies General Circulation Model (GISS GCM) Model 3. The data set specifies the top and bottom depths and the percent abundance of sand, silt, and clay of individual soil horizons in each of the 106 soil types cataloged for nine continental divisions. When combined with the World Soil Data File, the result is a global data set of variations in physical properties throughout the soil profile. These properties are important in the determination of water storage in individual soil horizons and exchange of water with the lower atmosphere. The incorporation of this data set into the GISS GCM should improve model performance by including more realistic variability in land-surface properties.

Bell System Technical Journal, 51: 1. January 1972 pp 87-121. Soil Burial Tests: Effect of Soil Burial Exposure on the Properties of Rubber, Crosslinked Polyethylene, and Vulcanized Wire Coatings. (Bebbington, G.H.)

Information regarding the effects of multipurpose tree species in parkland agroforestry practice on soil conditions in Ethiopia is very scarce. The study was intended to investigate the effects of parkland Mangifera indica and Ziziphus spina christi trees species on the selected physicochemical properties of soil within and outside the canopy of the tree and at varying soil depths in Sofi district, Harari Region Ethiopia. Accordingly, twelve trees six for each isolated and nearly similar M. indica and Z. spina christi trees in crop field growing on more or less similar site conditions, management practices, canopy coverage and height were selected. Soil samples were collected from under the canopy of trees, edge of canopy, outside of the canopy 10 m from the trees in crop field and three soil depth 0 20 cm, 20 40 cm and 40 60 cm for analysis of selected soil physical and chemical properties. The result of the study revealed that lower soil bulk density was observed under trees canopy and surface soil of both tree species than open field and subsurface soil p 0.01 , While soil water content at FC, PWP and AWHC were significantly p 0.01 higher on subsurface than surface soil and under canopy of trees than open fields. However, no significant differences were observed in the texture and pH of soil p 0.05 . Soil EC, SOC, SCS, TN, AP and CEC were significantly p 0.01 higher under the trees canopy than open field and on the surface than subsurface soil for both trees species in sorghum field. It can be concluded that these tree species have the potential to improve soil fertility and moisture beneath their canopy. Thus, the finding suggests that retaining these important trees species with proper management on farmland improve and maintain soil fertility and reduce chemical fertilizer amendments. Bira Cheneke Feyissa | Solomon Estifanos Bekele | Samuel Feyissa "Effect of Parkland Ziziphus Spina-Christi and Mangifera Indica Trees on Selected Physicochemical Properties of Soil in Sofi District, Harari Region, Ethiopia" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-9 | Issue-1 , February 2025, URL: https://www.ijtsrd.com/papers/ijtsrd75115.pdf Paper Url: https://www.ijtsrd.com/other-scientific-research-area/other/75115/effect-of-parkland-ziziphus-spinachristi-and-mangifera-indica-trees-on-selected-physicochemical-properties-of-soil-in-sofi-district-harari-region-ethiopia/bira-cheneke-feyissa

Analysis of soil quality from Shirala area of Sangli District. Black soil Concern study is to determine the quality of soil in ShiralaTahasil In village Wadibhagai. Thus about numbers of samples from area were examined to assess the soil properties as well as for obtaining the information about soil quality, evaluation of fertilizer status, indigogenous soil fertility. To understand fertility of soil, it is necessary to carry out analysis. The different parameter was observed. This observed properties before & after sparing of spent wash all properties was increases and both of these properties was compared standard limiting values and improved amount was compared again standard   limiting value.  This data mentioned into this paper [7].

Comprehend and forecasting the engineering characteristics of fine-grained soils is crucial for the practice of geotechnical engineering. Fine-grained soil contamination occurs on a daily basis as a result of industrial development and pipeline or reservoir leaks. Due to the influence of the surrounding condition, substantial damage occurs in the foundations of buildings. The presence of industrial wastewater in the soil contributes to a change in its physical, chemical and mechanical properties, and then negatively affects the foundations of various facilities. In addition to environmental issues such as groundwater contamination, the changing of the geotechnical qualities of polluted soil is a concern. As a result of the concentrations of pollutants resulting from the industrial businesses such as dairy products industry, spinning and weaving factories, paper factories and leather wastewater are extremely high in developing countries. Disposal of untreated industrial waste water is a common problem in these countries. This paper describes an experimental investigation that was conducted to explore the effect of four types of industrial wastewater; dairy (DW), textile (TW), leather (LW) and paper (PW) on the deformational behavior of fine-grained soil. Fine-grained soil was exposed to DW, TW, LW and PW for 2, 4, 6, 8, 12, and 16 months. Four remolded soil groups of samples are generated for this investigation and combined with the four types of industrial wastewater of constant moisture content (70%). The Atterberg limits, plasticity index, specific gravity, free swelling, optimal moisture content (OMC), and maximum dry density (γdmax) of each mixture were calculated after 0, 2, 4, 6, 8, 12, and 16 months of mixing soil with industrial waste water. Comparisons were made between the results of four groups of samples.

Increase in knowledge of Chemical properties of soil will prevent or reduce road failure in tropical climate such as Nigeria. This study aimed at assessing some chemical properties of lateritic soil deposited in Isan - Ekiti, South-western Nigeria. Soil samples collected from the study area were subjected to CEC, Organic Carbon content, pH and Refractive Index tests.  The CEC, Organic Carbon content, pH and Refractive Indices values for all the soil samples varied from 35.00 to 58.00 , 31.00 to 46.00 , 6.00 to 6.21 and 1.529 to 1.533 respectively. It could be generally observed there were presence of large deposit of lateritic soil with large contents of clay and its minerals.  The soil in the study area were acidic in nature though weak and likely to have high retention capacity. There could be presence of clay minerals such as Allophone, Chlorite, Illite and Steatite in study area's soil. Further study on the other Engineering properties of the soil should be carried out.  by Silas A. Oladapo | Adeyemi E. Adetoro "Assessment of some Chemical Properties of Isan - Ekiti Soil, Southwestern Nigeria"  Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-6 , October 2018,  URL: http://www.ijtsrd.com/papers/ijtsrd18571.pdf Direct Link: http://www.ijtsrd.com/engineering/civil-engineering/18571/assessment-of-some-chemical-properties-of-isan---ekiti-soil-southwestern-nigeria/silas-a-oladapo

Today, all over the World, soil plays major role in Civil Engineering works or construction. Its thorough assessment is impossible if its Engineering properties were overlooked. The aim of this study is to analyze some Engineering properties of lateritic soil deposited in Isan - Ekiti, South-western Nigeria. Soil samples collected from the study area were subjected to Atterberg Limits, CBR and Grain Size laboratory tests. It is observed that the LL, PL, PI, SL and CBR values varied from varied from 41.10 to 57.50 , 24.60 to 35.50 , 14.80 to 22.70 , 0.32 to 0.61 and 4.38 to 30.21 respectively for all the soil samples.  It could be generally observed all the soil samples were classified as granular soil material with mainly silty or clayey gravel and sand constituent materials with some stone fragments. Their general rating as sub-grade materials is ""Excellent to good"". They were grouply classified as A - 2 - 7 and were only good for sub grade filling materials. There is need for further study on deposited materials around the study area for good base and sub base courses materials.  by Adeyemi E. Adetoro | Silas A. Oladapo "Analyses of some Engineering Properties of Isan - Ekiti Soil, Southwestern Nigeria"  Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-6 , October 2018,  URL: http://www.ijtsrd.com/papers/ijtsrd18570.pdf Direct Link: http://www.ijtsrd.com/engineering/civil-engineering/18570/analyses-of-some-engineering-properties-of-isan---ekiti-soil-southwestern-nigeria/adeyemi-e-adetoro

Introduction In parallel with the population growth, increasing food production using modern agricultural methods seems necessary. Application of chemical inputs and biodiversity reduction in agroecosystems lead to artificial ecosystems, requiring human intervention. Soil is an essential part of agroecosystems and the key to soil fertility is preserving the ecological biodiversity of the system. The use of management methods based on field hydrone inputs reduces the consumption of thorny inputs and reduces environmental degradation. The size and stability of the aggregates indicate the balance between the constituent and destructive factors of the aggregates. Different tillage methods are based on the soil physical and chemical properties. The purpose of this study was to investigate the effect of management methods on the physical and chemical properties of farm soil of the cities in Isfahan province. Materials and Methods We investigated the effect of management practices on physical and chemical properties in field soils in Esfahan province during 2011-2012. First, 6 fields are selected in each of 23 counties, and evaluation was conducted using questionnaires filled by farmers. Accordingly, the fields were classified in three groups (low input, medium input and high input). Two fields of each group input were selected and evaluated. Four points (30 centimeters of depth) at each hectare of field were randomly sampled. By mixing, one complete sample was obtained and carried to laboratory for further analyses. Soil texture was determined by hydrometric method, and electrical conductivity and pH were determined in saturated extract. Wet oxidation method was used to measure soil organic matter. To determine the stability of aggregates, soil samples were evaluated by wet sieving method. Results and Discussion   Results indicated that soil texture, aggregate stability, electrical conductivity and rate of organic matter in three management practices (low input, medium input and high input) were significantly different ( p < 0.01). The aggregate stability in low input fields had the highest value (0.72) and in high input fields had the lowest value (0.42).The soils in low and high input fields include maximum and minimum organic matter (2.05% and 1%), respectively. The field management methods had a significant effect on the amount of organic matter. The pH of soil samples did not show a significant difference. The electrical conductivity of the soil solution was different between three planting systems analyzed. In high input fields, the electrical conductivity values of the soil solution had the highest values. It seems that excessive consumption of chemical inputs in high input fields increased the electrical conductivity of soil solution. Other researchers have reported that the soil solution electrical conductivity depends on several factors such as the fertilizer type and their consumption, irrigation method and soil type.   Conclusion Reduced chemical fertilizers consumption and less entry of machinery increase the stability of aggregates in low input fields. The reduced or non-tillage methods in fields that preserve more crop residues on the soil surface increase the aggregates’ consistency and thus improve their stability. Application of conventional plowing, chemical inputs, and no crop rotation reduce soil organic matter content.   Acknowledgment I would like to express my sincere gratitude to the professors, staff, and students of the Faculty of Agriculture of Ferdowsi University of Mashhad who helped me in carrying out this research.

This article is from PLoS ONE , volume 9 . Abstract Plant diversity drives changes in the soil microbial community which may result in alterations in ecosystem functions. However, the governing factors between the composition of soil microbial communities and plant diversity are not well understood. We investigated the impact of plant diversity (plant species richness and functional group richness) and plant functional group identity on soil microbial biomass and soil microbial community structure in experimental grassland ecosystems. Total microbial biomass and community structure were determined by phospholipid fatty acid (PLFA) analysis. The diversity gradient covered 1, 2, 4, 8, 16 and 60 plant species and 1, 2, 3 and 4 plant functional groups (grasses, legumes, small herbs and tall herbs). In May 2007, soil samples were taken from experimental plots and from nearby fields and meadows. Beside soil texture, plant species richness was the main driver of soil microbial biomass. Structural equation modeling revealed that the positive plant diversity effect was mainly mediated by higher leaf area index resulting in higher soil moisture in the top soil layer. The fungal-to-bacterial biomass ratio was positively affected by plant functional group richness and negatively by the presence of legumes. Bacteria were more closely related to abiotic differences caused by plant diversity, while fungi were more affected by plant-derived organic matter inputs. We found diverse plant communities promoted faster transition of soil microbial communities typical for arable land towards grassland communities. Although some mechanisms underlying the plant diversity effect on soil microorganisms could be identified, future studies have to determine plant traits shaping soil microbial community structure. We suspect differences in root traits among different plant communities, such as root turnover rates and chemical composition of root exudates, to structure soil microbial communities.

This article is from PLoS ONE , volume 9 . Abstract Plant diversity drives changes in the soil microbial community which may result in alterations in ecosystem functions. However, the governing factors between the composition of soil microbial communities and plant diversity are not well understood. We investigated the impact of plant diversity (plant species richness and functional group richness) and plant functional group identity on soil microbial biomass and soil microbial community structure in experimental grassland ecosystems. Total microbial biomass and community structure were determined by phospholipid fatty acid (PLFA) analysis. The diversity gradient covered 1, 2, 4, 8, 16 and 60 plant species and 1, 2, 3 and 4 plant functional groups (grasses, legumes, small herbs and tall herbs). In May 2007, soil samples were taken from experimental plots and from nearby fields and meadows. Beside soil texture, plant species richness was the main driver of soil microbial biomass. Structural equation modeling revealed that the positive plant diversity effect was mainly mediated by higher leaf area index resulting in higher soil moisture in the top soil layer. The fungal-to-bacterial biomass ratio was positively affected by plant functional group richness and negatively by the presence of legumes. Bacteria were more closely related to abiotic differences caused by plant diversity, while fungi were more affected by plant-derived organic matter inputs. We found diverse plant communities promoted faster transition of soil microbial communities typical for arable land towards grassland communities. Although some mechanisms underlying the plant diversity effect on soil microorganisms could be identified, future studies have to determine plant traits shaping soil microbial community structure. We suspect differences in root traits among different plant communities, such as root turnover rates and chemical composition of root exudates, to structure soil microbial communities.

This article is from PLoS ONE , volume 9 . Abstract Plant diversity drives changes in the soil microbial community which may result in alterations in ecosystem functions. However, the governing factors between the composition of soil microbial communities and plant diversity are not well understood. We investigated the impact of plant diversity (plant species richness and functional group richness) and plant functional group identity on soil microbial biomass and soil microbial community structure in experimental grassland ecosystems. Total microbial biomass and community structure were determined by phospholipid fatty acid (PLFA) analysis. The diversity gradient covered 1, 2, 4, 8, 16 and 60 plant species and 1, 2, 3 and 4 plant functional groups (grasses, legumes, small herbs and tall herbs). In May 2007, soil samples were taken from experimental plots and from nearby fields and meadows. Beside soil texture, plant species richness was the main driver of soil microbial biomass. Structural equation modeling revealed that the positive plant diversity effect was mainly mediated by higher leaf area index resulting in higher soil moisture in the top soil layer. The fungal-to-bacterial biomass ratio was positively affected by plant functional group richness and negatively by the presence of legumes. Bacteria were more closely related to abiotic differences caused by plant diversity, while fungi were more affected by plant-derived organic matter inputs. We found diverse plant communities promoted faster transition of soil microbial communities typical for arable land towards grassland communities. Although some mechanisms underlying the plant diversity effect on soil microorganisms could be identified, future studies have to determine plant traits shaping soil microbial community structure. We suspect differences in root traits among different plant communities, such as root turnover rates and chemical composition of root exudates, to structure soil microbial communities.

Soil stabilization is the process which involves enhancing the physical properties of the soil in order to improve its strength, durability etc. by blending or mixing with additives. The different types of method used for soil stabilization are Soil stabilization with cement, Soil stabilization with lime, Soil stabilization using bitumen, Chemical stabilization and a new emerging technology of stabilization by Geo textiles and Geo synthetic fibers. In this study, we are making use of bamboo fibers as geo synthetic material for stabilization of soil. With the introduction of bamboo fibers to the soil the CBR values will improve and thickness of pavement layer also gets reduced. It also reduces the intensity of stress on subgrade. Bamboo fibers is such a geosynthetic material which is easily available, ecofriendly and also cost effective. With the application of soil stabilization method in construction the overall cost gets reduced when compared to the ordinary method of construction. The Highway Research Board HRB classification of the soil strata like black cotton soil and sedu soil is done using suitable sampling technique such as Core Cutter Method. To determine the characteristics like Grading by Sieve Analysis, Atterbergs Limits i.e Liquid limit using Cone Penetration Method and Casagrande Method, Plastic limit by rolling the sample to 3mm diameter thread, Shrinkage limit using Shrinkage apparatus, Optimum Moisture Content and Maximum Dry Density using Standard Proctor Test and also California Bearing Ratio by conducting CBR test. The pavement thickness was designed using pavement design catalogues published by IRC SP 20 2002. The estimation for the street is finished by considering the thing, for example, Earthwork Excavation for Roadway and Drains, Jungle Cutting, compacting and reviewing and so forth., according to SR 2016 17, PW, P and IWT circle Andhra Pradesh and proposing of particulars for the blend of Bamboo strands as Geo Synthetic material for adjustment. By M. Anvesh Kumar | U. Swathi "Utilization of Bamboo Fibers for Modification of Black Cotton Soil Properties" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27831.pdf Paper URL https://www.ijtsrd.com/engineering/civil-engineering/27831/utilization-of-bamboo-fibers-for-modification-of-black-cotton-soil-properties/m-anvesh-kumar

Understanding and prediction of engineering properties of fine-grained soils is of vital importance in Geotechnical Engineering practice. Fine-grained soil contamination occurs on a daily basis as a result of industrial development and pipeline or reservoir leaks.Due to the influence of the surrounding condition, substantial damage occurs in the foundations of buildings. The presence of industrial wastewater in the soil contributes to a change in its physical, chemical and mechanical properties, and then negatively affects the foundations of various facilities. . In addition to environmental issues such as groundwater contamination, the changing of the geotechnical qualities of polluted soil is a concern. As a result of the concentrations of pollutants resulting from the businesses such as Dairy products industry and spinning and weaving factories, are extremely high in developing countries. Disposal of untreated industrial waste water is a common problem in these countries. This paper describes an experimental investigation that was conducted to explore the effect of two types of industrial waste water the first type was dairy industrial waste water (DW) and the second was textile industrial waste water (TW) on the deformational behavior of fine-grained soil. Fine-grained soil used in this research was obtained in a natural phase from a soil excavation site for the construction of a residential building in the village of El-Kom Al-Ahmar, Shibin El-Qanater, Qualiobiyah governorate Fig.1, which was exposed to DW and TW at 2, 4, 6, 8, 12, and 16 months, Two remolded soil samples are generated for this investigation and combined with different types of industrial wastewater of constant moisture content (70%). The Atterberg limits, plasticity index, specific gravity, free swelling, optimal moisture content (OMC), and maximum dry density (γdmax) of each mixture were calculated after 0, 2, 4, 6, 8, 12, and 16 months of mixing soil with industrial waste water, the results revealed that as soil matures, the optimum moisture content (O.M.C) and free swelling values of the soil containing DW, TW rise after the addition of pollutants, whereas the maximum dry density, specific gravity (GS), and cohesiveness decrease.

Soil properties and yield of pepper are affected by soil fertility and cultural practices such as tillage. Although, composts improve soil structure and enhance soil fertility and crop yield, limited information is available on the combined effect of tillage and compost on the yield of pepper. Therefore, a study was conducted in 2010 and 2011 to evaluate the effect of almond leaf-based composts on soil properties and yield of C. chinense under the two commonly practiced tillage systems in Ibadan. The influence of thirteen experimental treatments comprising of almond leaf-based composts [Almond leaves + Poultry manure (AP) at 9.7, 12.1, and 14.5 t/ha; Almond leaves + Cattle manure (AC) at 14.3, 17.9, and 21.5 t/ha; and Almond leaves + Swine manure (AS) at 13.0, 16.3, and 19.6 t/ha]; NPK 15-15-15 at 0.2, 0.25, and 0.3 t/ha; and a control (without fertilizer) on the growth and yield of C. Chinense were investigated in a Screen house. Each treatment was mixed with 5 kg soil and arranged in a completely randomized design with four replications. The performances of the best rates in each treatment: AP (14.5 t/ha), AC (14.3 t/ha), AS (13.0 t/ha), NPK (0.25 t/ha) and control from Screen house studies, under two tillage methods: Manual Clearing (MC) and Manual Ridging (MR) were investigated in the field. The ten treatment combinations (MC; AP/MC; AC/MC; AS/MC; NPK/MC; MR; AP/MR; AC/MR; AS/MR and NPK/MR) were laid as randomised complete block design with four replications. Data were collected on plant height (PH), number of leaves (NL), and number of branches (NB), stem girth (SG), root length (RL) and fruit yield (FY) of pepper. Soil samples were collected and analysed for changes in nutrient content, soil porosity (SP), bulk density (BD), soil temperature (ST) and pH. Data were analysed using descriptive statistics and ANOVA at 0.05. In the Screen house, significant (p<0.05) differences were observed among the treatments for PH, NL, NB, SG and FY of pepper. The FY ranged from 44.5±1.7 (control) to 68.4±3.1 g/pot (AC, 14.3 t/ha). The highest FY of 68.4±3.1 g/pot of pepper recorded by AC (14.3 t/ha) was higher than those from NPK (0.25 t/ha) by 13.6%. In the field; PH, NL, NB, RL and SG of pepper were significantly (p<0.05) higher under MR than MC, respectively. The SP (54.4±1.6 and 46.4±1.8%), carbon (18.5±1.7 and 14.4±1.4 g/kg), nitrogen (4.3±0.4 and 3.3±0.4 g/kg), K (0.3±0.1 and 0.2±0.1cmol/kg),calcium (10.5±1.0 and 8.3±0.9 cmol/kg), CEC (15.9±1.3 and 13.4±1.2cmol/kg) and FY (6.6±0.6 and 3.6±0.3 t/ha) were significantly (p<0.05) higher under MR than MC, respectively. The BD and ST under MR were not significantly (p<0.05) different from MC. The FY under almond leafbased composts increased in the order: AS (5.0±0.7 t/ha) ˂ AP (5.3±0.7 t/ha) ˂ NPK (5.7±0.8 t/ha) ˂ AC (6.9±1.1 t/ha). Soil pH under compost-tillage (6.8±0.1) was higher than that of NPK-tillage (5.4±0.1) combinations. The SOC (25.5±2.7 g/kg), N (6.4±0.6 g/kg), K (0.5±0.2 cmol/kg), SP (59.5±0.9%) and FY (10.0±0.5 t/ha) under the combination of 14.3 t/ha AC/MR was significantly (p<0.05) higher than other treatments. Soil properties and yield of pepper were greatly improved under almond leaf-based compost and manual ridging. Thus, the combination of almond leavescattle manure compost at 14.3 t/ha and manual ridging is recommended for enhancing soil properties for pepper production in Ibadan.  

Bulletin (West Virginia University. Agricultural Experiment Station)

The aim of this study was to assess the possibility of using biological and biochemical parameters in the evaluation of forest soil quality and changes caused by land use. The study attempted to determine a relationship between the enzymatic activity of soil, the number of earthworms and soil physico chemical properties. The study was carried out in central Poland in adjoining Forest Districts (Przedbórz and Smardzewice). In soil samples taken from 12 research plots, basic physico-chemical properties, enzyme activity (dehydrogenase, urease) and density and biomass of earthworms were examined. Enzyme activity showed a large diversity within the forest site types studied. The correlations between the activity of the enzymes studied and C/N ratio indicated considerable importance of these enzymes in metabolism of essential elements of organic matter of forest soils. Urease and dehydrogenase activity and earthworm number showed susceptibility to soil pH, which confirmed relationships between enzyme activity and abundance of earthworms and soil pH in H2O and KCl.

A number of simple experiments were performed on a microwave reflectometer, operating at 60 MHz, to test the feasibility of its use as a tool for accurately measuring the complex electrical properties of soils. Such knowledge could be used to predict electromagnetic wave attenuation, the volumetric moisture contained within soil near the probe surface, and, through the relative changes in soil properties either over surface areas or as a function of depth below the surface, the presence of harmful contaminants. Background information contained within this report includes a review of similar microwave sensor applications and a description of the basic relationships used to convert sensor voltage measurements into relative dielectric permittivity and conductivity. Experiments were conducted to investigate the volume of soil that would be measured by the soil and to determine the sensitivity of the instrument. While permittivity measurements appeared to be quite good, conductivity measurements in low conductivity materials were not as reliable. A simple analytical study indicated that the conductivity measurements would be quite sensitive to the accuracy of the voltmeter being used by the reflectometer. In most soils, the frequency of operation and the sensitivity of this system will allow the field lines to extend about 1 cm away from the probe surface, making the probe ideal for surface measurements and well suited to being placed in a borehole or cone penetrometer environment to obtain vertical profiles of soil properties. Numerous improvements to the measurement system were recommended to improve its sensitivity and utility.

There are no author-identified significant results in this report.

Bell System Technical Journal, 51: 1. January 1972 pp 47-49. Soil Burial Tests: Effect of Soil Burial Exposure on the Properties of Electrical Grade Reinforced Plastic Laminates. (Kwei, T.K.)