Free Essay


In: Science

Submitted By cxc2087
Words 769
Pages 4
Introduction to Soil /
Soil Formation
LA7014 - Ecology / Technology I

What is the difference between dirt and soil?

Textbook Definition of Soil

Preferred Definition - “The unconsolidated material at or near the earth’s surface that has properties due to its proximity to the surface”

Long Version - “the unconsolidated mineral or organic matter on the surface of the earth that has been subjected to and shows the effects of genetic and environmental factors of: climate (including water and temperature effects) and macro- and microorganisms, conditioned by relief, acting on parent material over a period of time”

Importance of Soil

"Essentially, all life depends upon the soil .... There can be no life without soil and no soil without life; they have evolved together." Charles E. Kellogg

"The nation that destroys its soil, destroys itself."
Franklin D. Roosevelt

"While the farmer holds the title to the land, actually it belongs to all the people because civilization itself rests upon the soil." Thomas Jefferson

Importance of Soil

Medium in which plants are grown for food and fiber.

Mechanical support for plant roots, such as trees.

Physical support for structures, roads, sidewalks, etc.

Home for millions of organisms.

Air-storage facility.

Mineral supplement for people (in some regions of the world)

Earth’s compost pile.

Soil Sphere Theory

Pedo = Soil

Bio = Plant

Litho = Rock

Hydro = Water

Atmo = Air

Can you see how all of these are interrelated? A Few Definitions

Unconsolidated material: refers to loose materials

Typically soil profiles consist of layers (horizons) of unconsolidated material over a parent material such as bedrock Soil Profile: A vertical section of soil through multiple horizons that extends into the parent material

Ex: Ruston series

State soil of Louisiana

Soil Horizons

Defined: A layer of soil or soil material approximately parallel to the land surface and differing from adjacent genetically related layers in physical, chemical, and biological properties or characteristics such as color, structure, texture, consistency, kinds and number of organisms present, degree of acidity or alkalinity, etc.

6 Master horizons (O, A, E, B, C, R)

Numerous subordinates (lower case letters)

Further describe master horizon attributes

Parent Material

“The unconsolidated and more or less chemically weathered mineral or organic matter from which soils form” (Brady)

“The kind of mineral or organic materials in which the soil formed, including kinds of rock from which the regolith was derived” (USDA Soil Survey Manual)

Types of Parent Material

Residuum: Original unweathered material

Lacustrine: Lake deposited

Marine: Ocean deposited

Colluvium: Gravity deposited

Eolian: Wind deposited

Moraine/till: Ice deposited

Alluvium: Stream/river deposited

Parent Material Diagram
From Brady, Nature and Property of Soils 13th ed.

Soil Formation Factors

Parent Material


Living organisms, microbes, etc.


Precipitation, temperature


Inorganic vs. organic

Relief, landscape position


Soil Formation

Pedogenesis - The formation and development of the soil profile.

The “Pedon” is the three-dimensional body of soil used as the soil base of reference.

“Genesis” is often referred to as “beginning.”

The Rock Cycle

Rocks are merely combinations of minerals.

Rock formation is determined by different environmental factors. The Earth’s Crust

Chemists recognize over 100 elements that make up everything tangible on earth.

The earth’s crust is made up of many of the elements but the most abundant are the following:









Rock Types

Igneous Rocks - Include granite and their metamorphic associates.

Make up the bedrock foundation of some continents.
Crystalline structure forms as magma cools. The slower the cooling, the larger the crystal structure.

Sedimentary Rocks - Sandstone, Shale, and Limestone.

Make up the bedrock foundation of 3/4 of the land area on earth.
Deposited as loose layers of sediment.

Metamorphic Rocks - Quartzite, Marble, Slate, and Gneiss.

Igneous and Sedimentary Rocks are altered by heat and pressure.

Sandstone forms Quartzite, Limestone forms Marble, etc.

Rock Weathering

Just as plants and animals decay, rocks are weathered through naturally occurring physical and chemical forces causing rocks to be weathered into

Collectively saprolite is call the Regolith of the earth, which is composed of the loose mineral materials above solid bedrock.

Rock Weathering

Lichens are composed of an alga and a fungus and are often one of the first organisms to colonize exposed rocks.

These organisms, along with cyanobacteria, produce weak acids that dissolve nutrients within the rock and begin to build a humid mat capable of supporting mosses, and eventually higher plants.

Rock Weathering

Physical Weathering - The breaking down of rocks into smaller pieces with no change in the molecular arrangement within the minerals.



Freeze - Thaw

Tree Roots

Chemical Weathering - Chemical reactions that alter the molecular composition of rocks.






Similar Documents

Free Essay

Soil Erosion

...and Solutions of Soil Erosion Renfang(Alice) Liao Academic Skills 300-1 Professor Smithwick Aug 17, 2012 Introduction Soil erosion is a global issue troubling most of the countries. China ranked 129 among the 142 environmental suspensibility evaluated countries; one of the reasons is the serious soil erosion. 19% of China's land is affected by soil erosion, which is one of the highest rates (Liu& Diamond, 2005: 1181). The statistics are thought-provoking, and the effects of soil erosion are significant. In fact, soil erosion is a part of a vicious circle. Scientists and technicians around the world are working hard to find out the better and more efficient ways to monitor and control soil erosion. Soil erosion is a progress in which soil particles are carried away by force such as water ,wind and gravity. Water and wind erosion are the most important erosion types classified by the erosive agents (Toy, Foster, and Renard, 2002: 55). In this report, the vicious circle of soil erosion, reduction of vegetations and sediments in river is discussed. Among the technologies applied in soil management, the one suitable for local condition is the best. Discussion Soil Erosion and Vegetation Soil Erosion's effects on Vegetation Plants absorb what they need from soil with roots. The topsoil provides the best environment for plants' roots with loose structure, enough air, and rich organisms, but it is removed firstly through soil erosion......

Words: 922 - Pages: 4

Free Essay


...Soil Test, Masalah dan Aplikasinya pada Tanah Lunak Ir. Muhrozi, MS Lab. Mekanika Tanah Jurusan Teknik Sipil Universitas Diponegoro Pendahuluan Keberhasilan pelaksanaan suatu proyek sangat ditentukan oleh : input data (data penyelidikan tanah) dengan ketelitian yang tinggi, perencanaan (dokumen kontrak/gambar) yang mantap, dan pelaksanaan konstruksi dengan metode kerja yang tepat serta kontrol/pengawasan pada saat pelaksanaan dilakukan secara ketat. Pada akhir-akhir ini banyak masyarakat umum yang menanyakan kepada kita (orang sipil) dengan nada heran dan menyindir sebagai berikut : mengapa akhir-akhir ini banyak bangunan sipil yang runtuh dibanding dengan masa lalu (zaman Belanda) ?, padahal insinyur di Indonesia sekarang sangat banyak. Pertanyaan yang agak menyindir tersebut perlu kita sikapi dengan bijak, instrospeksi kepada diri kita masing-masing dan sambil mencari beberapa penyebab yang aktual, sehingga kita dapat mencari jawaban/solusi yang tepat untuk perbaikan masa yang akan datang. Menurut Penulis, penyebab banyaknya kegagalan konstruksi bangunan sipil pada akhir-akhir ini disebabkan oleh eksploitatifnya pemanfaatan tanah yang melebihi daya dukung tanah secara umum, sebagai contoh : pemanfaatan lahan gambut/rawa/tambak untuk perumahan dapat menyebabkan penurunan yang berlebihan, pembangunan jalan raya dengan timbunan yang melebihi tinggi kritis (Hcr) dapat menyebabkan sliding atau kelongsoran, timbunan optrit yang tinggi mengakibatkan dorongan pada abutment dan...

Words: 2648 - Pages: 11

Premium Essay

Soil Report

...Soils Field and Laboratory Report Introduction On the 23rd of October 2013, I was set to analyse some soil samples. I decided to take my samples from Avenham park in Preston, Lancashire. A soil pit was dug and some samples were taken, those samples were later taken to the laboratory and passed through series of test. Measuring of moisture content, PH level, and the percentage organic mater content were the major carried out on the samples. The main purpose for analysing the soil samples is to identify the processes that takes place within the soil at a particular location and to identify the other factors affecting these processes and lastly to make classifications based on the field observation and results obtained from the laboratory. Chosen Site The site chosen is located at Avenham park in Preston, Lancashire River Ribble River Ribble Approximately where the site it located Approximately where the site it located Avenham park Avenham park Figure 1: Map of preston, Lancashire. Locating the site where samples where taken. ( google map, n.d) The site where the soil pit was dug is a vast piece of managed farm land about a hundred meters wide. There is a footpath located at the right side of River Ribble after crossing the old tam bridge to the right. The footpath serves as a link between the site , avenham and west cliff leading to the preston train station. This site was selected because it......

Words: 296 - Pages: 2

Free Essay

Soil Investigation

...DETAIL SOIL INVESTIGATION INTRODUCTION SOIL INVESTIGATION is carried out to design a right type of foundation safely and economically. A designer requires adequate information about the physical properties and the arrangement of the materials underground. The field and laboratory investigations needed to get this necessary information is known as soil exploration. The study of complete soil investigations can be grouped as follows : • Objectives or purposes, • Preliminary investigations, • Methods of site exploration, • Depth and spacing of trial pits and bore holes, • Choice of a method, • Recording of data. The investigation of the geology and previous uses of any site, together with the determination of its engineering, environmental and contamination characteristics is fundamental to both safe and economic development. [pic] SOIL TESTING • Soil tests can be conducted on samples that truly represent the soil at the site. • Soil sampling, testing and test interpretation must be conducted with guidance from specially trained and experienced personnel. • Proper soil testing is proven to be a reliable basis for the design of foundations and commonly used in site investigations to indicate their potential use and limitations. • Based on the premise that the behavior of soil masses under imposed conditions can be predicted if certain soil properties can be measured. • The results of soil tests must be interpreted based on past......

Words: 1681 - Pages: 7

Free Essay

Soil Horizon

...A soil horizon is a layer generally parallel to the soil surface, whose physical characteristics differ from the layers above and beneath. Each soil type usually has three or four horizons. Horizons are defined in most cases by obvious physical features, chiefly colour and texture. These may be described both in absolute terms (particle size distribution for texture, for instance) and in terms relative to the surrounding material (i.e., "coarser" or "sandier" than the horizons above and below). The differentiation of the soil into distinct horizons is largely the result of influences, such as air, water, solar radiation and plant material, originating at the soil-atmosphere interface. Since the weathering of the soil occurs first at the surface and works its way down, the uppermost layers have been changed the most, while the deepest layers are most similar to the original parent material. Identification and description of the horizons present at a given site is the first step in soil classification at higher levels, through the use of systems such as the USDA soil taxonomy or the Australian Soil Classification. The World Reference Base for Soil Resources lists 40 diagnostic horizons.[1] Soil scientists often dig a large hole, called a soil pit (usually several meters deep and about a meter wide) to expose soil horizons for study. The vertical section exposing a set of horizons, from the ground surface to the parent rock, is termed a soil profile. Most soils, especially...

Words: 400 - Pages: 2

Free Essay

Soil Erosion

...Soil Erosion Environmental Science Wanda Black 2/12/15 Soil is solid material of geological and biological origin that is changed by chemical, biological and physical processes. This gives the soil the ability to support plant growth. Erosion is the process of soil and humus particles being picked up and carried away by water or wind. Erosion follows when soil is bared and exposed to the elements. This is how soil erosion happens as well as when there are no plants or trees and soil getting swept into the river. The negative impacts of soil erosion, is overgrazing, over cultivation and deforestation. Overgrazing is grassland that is constantly plowed and crops grown on it. The grasslands don’t get enough rain to support cultivated crops or are too steep for cropping and for grazing livestock. It reduces the ability of plants to grow and water to not penetrate the land. Overgrazing can be prevented by farmers getting information from the U.S. Natural Resources Conservation Service (NRCS). They do testing and analysis of soil. The NRSC have helped decrease soil erosion from 2.1 billion tons in 1992 to 1.7 billion tons in 2007 and made consequences of improved conversion practices such as windbreaks, grassed waterways and field border strips of perineal vegetation. If the land is left untreated it could cause a problem with the food chain. Overcultivation is when the soil has been plowed to control weeds and the soil is exposed to wind and water. The soil......

Words: 373 - Pages: 2

Premium Essay

Soil Erosion

...1.0 Introduction Soil erosion has been accelerated in many areas of the world especially Australia. It becomes a biggest problem in Australia which leads Australians have to confront it. Soil erosion means the removal or disappearance of soil by water or wind. It may due to the poor cultivation, overgrazing and stripping of the land. Today, soil erosion is one of the most critical environmental problems in Australia which threatening farmlands, streams and village.  This report below is concentrate on the types, causes and preventing of soil erosion. 2.0 Types of soil erosion There have various types of soil erosion but the two major types of soil erosion that often occur in Australia which is water erosion and wind erosion. 2.1 Water erosion Water erosion is the most widespread erosion in Australia. There have several types of water erosion which is sheet, rill and gully erosion. Firstly, Raindrop can be a main problem for farmers when they strike bare soil. Rain can washes away seed and splashes soil into the air. If the fields are on a slope the soil is splashed downhill which causes deterioration of soil structure (Sydenham & Thomas, 2008). Hence, soil that has been separated by raindrops is more easily moved than soil that has not been separated. Sheet erosion is caused by raindrops whereas rill erosion and gully erosion caused by rainfall. Sheet erosion is defined as the uniform removal of soil in thin layers from sloping land. When rains run off the slope,......

Words: 459 - Pages: 2

Premium Essay

Soil and Glaciers

... University of Phoenix Material Soil and Glaciers Worksheet From Visualizing Earth Science, by Merali, Z., and Skinner, B. J, 2009, Hoboken, NJ: Wiley. Copyright 2009 by Wiley. Adapted with permission. Part 1 Size grades of soil are named sand, silt, and clay, which includes colloids. Size grades are defined using the metric system. Use Figure 4.8 from the textbook to fill in the following chart. Specify the type and size and description of the particle. In some cases, particle size will be less than some value or greater than another value. For instance, gravel is greater than 2.0 mm. |Name |Size |Description | |Gravel |>2.0 mm |Gravel is very small, irregular pieces of rock and stone. Gravel is more rough and rocky than sand, and | | | |smaller than stones. The word gravel comes from the French word gravele, "gravel or sand," which in turn | | | |comes from grave, "seashore or sand ("Gravel ", 2015). | |Sand |0.05 |sedimentary material, finer than a granule and coarser than silt, with grains between 0.06 and 2.0 | | | |millimeters in diameter ("Sand", 2003-2015). | |Silt |0.0002 |Silt is...

Words: 1793 - Pages: 8

Free Essay


...The Nature of Soil Tara D. Weldon GENS 320 Physical Geography August 2, 2015 Soil is a nearly infinitely varying mixture of weathered mineral particles, decaying organic matter, living organisms, gases, and liquid solutions. There are five principal soil forming factors responsible for soil development: Geology, climate, topography, biology, and time. (geologycafe, 2015) Geologic Factor: Over many years (thousands and/or millions) a stony surface can be broken down by weather, such as rain, wind and ice. This process is known as weathering. Climatic Factor: Warmer temperatures and an abundance of water have a tendency to speed up the formation of soil. Cooler temperatures and less precipitation slow down soil formation. Topographic Factor: In areas that are flat, soil tends to get deeper quicker than the surface erodes away. Which typically have deeper, more mature soil layer. On steep slopes, erosion takes place quicker than the formation of new soil. Which have thin layer of soil that is immaturely developed. Drainage is also a factor. Some locations become waterlogged. This blocks oxygen, which is important for soil formation. In those locations soil formation can become severely hindered. Biological Factor: Living organisms have an extensive impact on soil. A small fraction of soil contains living and dead lifeforms. However, the role of these lifeforms can't be underestimated. Roots from plant life dig deep into the soil, creating passages for water and air.......

Words: 759 - Pages: 4

Premium Essay

Soil Science of the production methods that use the organic crops such as Indigenous Microorganisms, fertilizer and some factors likes air, water and soil. In additions, large sums of money have been invested in providing irrigation and drainage infrastructure facilities to enable double cropping of rice using high yielding varieties with the latest agronomic practices in attempts to attain high rice yields. There is an alarming concern of a future demand for still higher levels of chemical to be used in order to maintain crop yields. Apart from this, the excessive dependence on chemical pose health hazards and are harmful rice agro-ecosystem and methods to sustain yield levels with the minimal use of chemicals. How to find the solutions? For the detail solution we are explain in this report. In this report, we include the best management practices that can be applied in natural farming process. The management practices are site selection, sediment management surface water and nutrient management. Other than that, we also included the advantages and disadvantages of natural farming of rice production. CHAPTER 2 2.0 MANAGEMENT PRACTICES IN NATURAL FARMING FOR RICE PRODUCTION Management practices for rice production implemented primarily for the purpose of conversing and protecting soil and water resources by controlling the movement of potential agricultural pollutants into surface and groundwater. However, in addition......

Words: 3463 - Pages: 14

Free Essay

Soil Investigation

...Soil investigation is often neglected or rejected by most clients on the basis of cost, despite the fact that the cost of carrying out a soil investigation is very little compared to the cost of the project Soil investigation is done for various purposes. In engineering, soil investigation is very necessary. It is essential to investigate the soil of the selected plot on which a structure will be constructed. Based on soil investigation a soil report is prepared for the purpose of designing the building foundation. When an engineer designs building foundation he/she must carefully read the report and design the foundation based on the data provided in the report. Soil investigation is required for the following purposes - To know the allowable bearing capacity of foundation for proposed building. To know the depth and type of foundation for the proposed building. To know the allowable passive resistance for the foundation of proposed building. To know the type, grading and nature of soil. To know the ground water level. Typical steps of soil investigation Soil investigation involves following steps –  Details planning for the sequence of operations.  Collecting the samples of soil from the plot.  Determining the soil characteristics by conducting field tests.  Study the condition of ground water level.  Collecting ground water sample for chemical analysis.  Soil exploration.  Testing all collected samples in the laboratory.  Preparation of......

Words: 1233 - Pages: 5

Premium Essay


...University of Phoenix Material Soil and Glaciers Worksheet From Visualizing Earth Science, by Merali, Z., and Skinner, B. J, 2009, Hoboken, NJ: Wiley. Copyright 2009 by Wiley. Adapted with permission. Part 1 Size grades of soil are named sand, silt, and clay, which includes colloids. Size grades are defined using the metric system. Use Figure 4.8 from the textbook to fill in the following chart. Specify the type and size and description of the particle. In some cases, particle size will be less than some value or greater than another value. For instance, gravel is greater than 2.0 mm. |Name |Size |Description | |Gravel |>2.0 mm |Limestone, dolomite , sand mixture of pebbles and small rocks | |Sand |>2mm |Quartz, gypsum,mollusk shell, coral fragments basalt pumice. colloids | |Silt |>0.01mm |Sedimentary rock, water, wind, ice include colloids. | |Clay |>0.002mm |Plasticity, firm,silicate, granite, alumina limestone, colloids | |Colloids |>0.00001mm |Molecules, colored glass, tiny grain of sand, silt, and clay. | Part 2 Soils have been classified......

Words: 729 - Pages: 3

Premium Essay

Soil and Glacier

...University of Phoenix Material Soil and Glaciers Worksheet From Visualizing Earth Science, by Merali, Z., and Skinner, B. J, 2009, Hoboken, NJ: Wiley. Copyright 2009 by Wiley. Adapted with permission. Part 1 Size grades of soil are named sand, silt, and clay, which includes colloids. Size grades are defined using the metric system. Use Figure 4.8 from the textbook to fill in the following chart. Specify the type and size and description of the particle. In some cases, particle size will be less than some value or greater than another value. For instance, gravel is greater than 2.0 mm. Name Size Description Gravel >2.0 mm Rock that is unconsolidated with fragments that have a general particle size range Sand 0.05 Sand particles are largerly formed by the physical break up of rocks. Sand has small surface areas and have an almost negligible role in the chemical activity of the soil. Sand particles are chemically insert or inactive. Silt 0.002 Silt is formed by physical weathering. Finer silits, which approach colloidal sizes, may exhibit some of the characteristics properties of clay. Clay Below 0.002 milimeters The clay fraction differs from the sands and silts in that it is composed predominantly of minerals formed as products of secondary weathering. The rock mineral will go through change before becoming clay minerals. Colloids 0.0001 – 0.00001 milimeters Like other soil particles, some colloids are minerals, whereas others are organic. Minerals......

Words: 1284 - Pages: 6

Free Essay

Soil Dynamics

...Course Teacher: Dr. Md. Mokhlesur Rahman Professor Department of Civil Engineering DUET Soil Dynamics: Soil Dynamics is the branch of soil mechanics which deals with the engineering properties and behavior of soil under dynamic stress, including the analysis of the stability of earth supported and earth retaining structures. The study of Soil dynamics include the machine foundations, impact loadings, dynamic soil properties, slope stability, bearing capacity, settlement, vibratory compaction, pile driving analysis and field testing, ground anchor systems, seismic design parameters, liquefaction, sheet pile walls and laboratory testing. Nature/sources of types of dynamic loading: * Dynamic loads on foundation and soil structure may act due to * Earthquake * Bomb blast * Operation of reciprocating and rotary machines and hammers * Construction operation such as pile driving * Quarrying * Fast moving traffic including landing aircraft * Wind * Loading due to wave action of water * Etc * The nature of each of these loads is quite different from the nature of the loads in the other cases. * Earthquakes constitute the single most important source of dynamic loads on structures and foundation. * Every earth quake is associated with a certain amount of energy released at its source and can be assigned a magnitude (m) which is just a number. * Table gives an idea of the energy associated with a particular...

Words: 15647 - Pages: 63

Premium Essay

Soil Conversion

...Soil Conservation Working Group Report This report provided content for the Wisconsin Initiative on Climate Change Impacts first report, Wisconsin’s Changing Climate: Impacts and Adaptation, released in February 2011. THE WISCONSIN INITIATIVE ON CLIMATE CHANGE IMPACTS 1st Adaptive Assessment Report Contribution of the Soil Conservation Working Group July 2010 Contour stripcropping in central Wisconsin Photo by Ron Nichols, USDA Natural Resources Conservation Service Participants of Working Group William L. Bland, Professor, Department of Soil Science, University of Wisconsin-Madison (Working Group Chair and lead author) Kelly R. Maynard, M.S. Agroecology, University of Wisconsin-Madison (Project Assistant) Jeremy Balousek, P.E., Urban Conservation Engineer, Dane County Land and Water Resources Department Denny Caneff, Executive Director, River Alliance of Wisconsin, Inc. Laura W. Good, Associate Scientist, Department of Soil Science, University of Wisconson-Madison Kevin Kirsch, Water Resource Engineer, Wisconsin Department of Natural Resources Patrick Murphy, State Resource Conservationist, Natural Resources Conservation Service John M. Norman, Emeritus Professor of Soil science, Department of Soil Science, University of Wisconsin-Madison James VandenBrook, Water Quality Section Chief, Wisconsin Department of Agriculture, Trade, and Consumer Protection Sara Walling, Water Quality Specialist, Wisconsin Department of Agriculture, Trade,......

Words: 12656 - Pages: 51