Structure of Laterites and Lateritic Soils
Soil structure is the size, shape and arrangement of mineral grains which form the soil mass. Soil structure is a major characteristic that influences all other engineering properties of the soil. Due to the processes of laterization, lateritic soils have attained distinct structural characteristics. It is an over-simplification to identify all temperate zone soils with dispersed structure and lateritic soils with concretionary structure (Remillon, 1967), lateritic soils may be on the whole more concretionary than most temperate zone soils.
According to Moh and Mazhar (1969), the increase in the thickness of free iron oxide coating of the soil particles is due to an increase in the degree of laterization.
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It was observed that the strength behaviour of lateritic soils is very dependent on the moisture content due to samples tested (Baldovin, 1969). It was also observed that due to a decrease in moisture content, there was an increase in cohesion and internal friction angle of the soil (Paulson, 1975). This character is associated to the variation in soil structure with varying moisture content, such that, as the soil dries out part of the hydrated colloidal iron and aluminum oxides dehydrates and forms strong bonds among certain soil grains which then causes an increase in …show more content…
The variations in strength with depth are due to variation in the degree of laterization and homogeneity in the profiles.
The strength and hardness of indurated laterite is a function of chemical composition, age and homogeneity. The iron-rich indurated laterites are harder than the alumina-rich ones (Nascimento et al., 1959).
Classification of Lateritic Soils
Attempts have been made to classify lateritic soils for so many years, but none of the proposed classification systems have been universally accepted. Maignien, 1966, grouped the classification systems into two and they are as follows:
a) Analytical classification system: this is based mainly on the morphological characteristics with a bias towards soil genetic considerations, and
b) Synthetic classification system: this is based on the genetic factors or soil-genetic processes or on properties of pedogenetic factors or
Aluminum is the most abundant metallic constituent in the crust of the earth; only the nonmetals oxygen and silicon are more abundant. Aluminum is never found as a free metal; commonly as aluminum silicate or as a silicate of aluminum mixed with other metals such as sodium, potassium, iron, calcium, and magnesium. These silicates are not useful ores, for it is chemically difficult, and therefore an expensive process, to extract aluminum from them. bauxite an impure h...
Mississippi has a variety of different soils .The three general soils are 1) the river flood plain, known as the Delta, 2) a loess region, or bands of soils formed in windblown material that adjoins the Delta, and 3) Coastal Plain. The Mississippi Delta is better for growing row crop, while the loess and Coastal Plain region are better for animal production and forestry. The loess and Coastal Plain regions are divided based on similar soils, geology, climate, water resources, and land use called Major Land Resource Areas. The Mississippi Delta’s soil comes from sediments left by flooding various rivers in the region, rather than being a typical Delta formed by the mouth of a river. In the Delta most of the land is farmed, with three-fourths of the cropland to the north. Controlling surface water and drainage are major soil management issues. In the Delta soils are naturally diverse because of their alluvial origin. Particle sizes within the sediment decrease as distance from the originating stream increase. Another factor in Delta soil formation us surface water movement over time, because soils that formed under standing water have different properties than soils formed under moving water. Soils with large amounts of clay particles have unique features. When the soil is dry, small round aggregates form at the surface that look like shotgun buckshot, which is where the popular name for Delta clay soils “buckshot” came from. Soils with large clay content have very slow water filtration rates; this has led to significant aquaculture and rice production in the region. When floodwaters receded in the Delta, strong winds blew some of the dry sediment left by flooded river to the adjacent uplands to form the loess areas. Because of eas...
Desert pavements are common landforms in arid regions. They consist of flat or sloping surfaces where stones are closely packed angular or rounded, and generally exhibit low relief (Mabbutt, 1977). Pavements tend to form on both alluvial fan toposequences and on weathering volcanic flow fields in arid regions. Soils are often found under desert pavements and they play an important role in the evolution of pavements (McFadden et. al., 1987). In the past there have been several theories as to the formation pavements and soil development beneath them. Deflation, or the erosion of finer grained particles from a surface, stone concentration by wash erosion and upward displacement of stone due to shrink and swell clay characteristics were at one time believed to be the main factors in the formation of desert pavements (Mabbutt, 1977). However, more recent research has shown that desert pavements are born and maintained at the surface, and that the soil below them is mainly eolian in origin. Slow accretion of eolian dust below the pavement is a process that eventually develops cumulate horizons. Eolian dust in environments where pavements often develop is rich in carbonate salts and clays due to the fact it often originates from nearby playa lake evaporate basins (McFadden et. al., 1987). Soils that form below the pavements over time develop calcic horizons and clay rich structure due to the influx of these eolian fines through the pavement surface. In turn the development of mature or plugged calcic horizons effects the form of the pavement surface because it alters the water drainage infiltration rate and causes pavements to decline.
As we have observed throughout the centuries, colonialism has immensely shaped the majority of countries of modern society. In the essay “The Impact of Colonization and Western Assimilation on Health and Wellbeing of Canadian Aboriginal People”, Cathy MacDonald & Audrey Steenbeek developed significant points that reflect as connections to the essay “Virgin Soils Revisited” emphasizing the devastating impact colonialism has had on the wellbeing and health initiatives imposed on the Native Americans and the Aboriginal people of Canada to this day. Both indigenous populations have endured the hardships of poor health, racial issues such as oppression, and cultural assimilations due to the long-lasting effects of colonialism.
As you may or may not know there are many types of farming. For those farming types, there are many tillage methods used. Depending where the farm is located is how the farmer knows what method to use. The methods used are No Till, One pass, Conventional, Conservation, and chisel plow plus. Let’s start out with No Till.
Holmes, Garnett, Bureau of Plant Industry United States, and Bureau of Chemistry and Soils United States. Soil Survey of The Yuma Area, Arizona-California. N.p.: Govt. print. off., 1905
(Ant)arctic (high-latitude) and alpine (mountain) areas are affected by relatively similar climates, as latitude and altitude produce similar meteorologic effects. In these geographic regions where temperature is at such a pronounced extreme, climate would seem to be the leading factor of soil development. It is my goal in this research paper to answer the following question: How do the soils of arctic and alpine areas differ? This idea, taken largely from an abstract by Birkeland (1975), will be explored through the comparison of the soils of these two geographic regions, and an analysis of the soil development factors in those environments.
Soil liquefaction describes a phenomenon whereby a saturated or partially saturated soil substantially loses strength and stiffness in response to an applied stress, usually earthquake shaking or other sudden change in stress condition, causing it to behave like a liquid. The phenomenon is most often observed in saturated, loose (low density), sandy soils. This is because the loose sand has a tendency to compress when a load is applied; dense sands by contrast tend to expand in volume. If the soil is saturated by water, then water fills the gaps between soil grains. In response to the soil compressing, this water increases in pressure and attempts to flow out from the soil to zones of low pressure (usually upward towards the ground surface). However, if the loading is rapidly applied and large enough, or is repeated many times (e.g. earthquake shaking, storm wave loading) such that it does not flow out in time before the next cycle of load is applied, the water pressures may build to an extent where they exceed the contact stresses between the grains of soil that keep them in contact with each other. These contacts between grains are the means by which the weight from buildings and overlying soil layers are transferred from the ground surface to layers of soil or rock at greater depths. This loss of soil structure causes it to lose all of its strength. According to the
In April 2013, a special memorial playground opened in Sea Bright, NJ. The project, The Sandy Ground Project: Where Angels Play, was organized by New Jersey’s Firefighter’s Mutual Benevolent Association. The playground was one of twenty-six playgrounds being installed in New Jersey, New York, and Connecticut towns honoring the children and teachers killed in the massacre at Sandy Hook Elementary School. Each town that received a playground was a town directly impacted by Superstorm Sandy. This particular playground is dedicated to Anne Marie Murphy, a special education teacher, wife, mother, and hero who passed away during the horrific shooting and is located on Sea Bright Beach which was brutally devastated by Superstorm Sandy.
Morphological characteristics such as color, texture, composition, etc. are uniform throughout the solum. There is no movement of soluble soil components. A concentration of soft powdery lime may be existing in or under the vertic horizon. Gypsum can occur either uniformly distributed over the matrix or in layers of gypsum crystals. Vertisols have a uniform particle size distribution throughout the solum, but texture may change abruptly where the substratum is reached. Dry Vertisols are very hard while wet Vertisols are plastic and sticky (Jewitt et al. 1979). It is generally true that Vertisols are crumbly over a narrow moisture range but their physical properties are greatly influenced by soluble salts or adsorbed sodium (Fao.org, 2014).
Examine the different kinds of leaves. Classify each according to the kind of leaf blades, kinds of leaf veins, Phyllotaxy, and leaf blade morphology.
The field of geology has many different branches. Some of these areas have hardly anything in common. The one thing that they all include, though, is that each one concentrates on some part of the Earth, its makeup, or that of other planets. Mineralogy, the study of minerals above the Earth and in its crust, is different from Petrology, the st...
As a result of this process, the mine sites "do not develop normal soil structure or support the establishment of a plant cover". Many mine sites have...
Home gardens offer a wide variety of benefits to the environment and serve a diverse group of people. Home gardening provides a source of fresh produce and free of chemicals, it also gives you complete control over the chemicals and products used during the growing process. A home garden allows you to pick the produce when its ripe, unlike produce at the store is often picked before its fully ripe. The quality and flavor of the freshly picked produce from home is better than the produce that might have unknown chemicals and was likely picked several days or weeks before being sold. The produce retains more nutrients when consumed shortly after being picked, making your home garden vegetables a healthier option. A garden also provides a positive environmental impact. The compost allows you to recycle certain kitchen and yard waste into a nutrient-rich additive for the garden. This provides natural fertilizer for you plants and reduces the wastes you produce. If you choose to avoid or limit chemical use, you reduce pollution from your gardening activities. Besides being good for the environment gardens have environmental gains for us. Gardening help control urban temperatures, If the environmental landscape design is effective it can cool your home in summer and warm it in winter, it can also reduce the energy cost by up to 20%. Gardening, and all the physical activity that goes along with it, leads to a better overall physical health, weight loss, improve you bones, and reduces the risk of having osteoporosis. “In a study of 3,310 older women, researchers from the University of Arkansas found that women involved in yard work and other types of gardening exercises had lower rates of osteoporosis than joggers, swimmers, and women wh...
Project title of field of study The effect of soil salinity on plant growth is part of botany, the study of plants. Botany: the study and science of plants in a particular habitat and region, it is the branch of biology that deals with the life of plants. Soil Salinity, Should We Be Worried? Introduction Soil salinity is said to be “bad” for plant growth, but is this really true?