HORT 102: Soil Properties. Cultivated Plants: Lecture 15. [Teresa Koenig] Slide #: 1 Slide Title: Intro Information Slide

Size: px
Start display at page:

Download "HORT 102: Soil Properties. Cultivated Plants: Lecture 15. [Teresa Koenig] Slide #: 1 Slide Title: Intro Information Slide"

Transcription

1 HORT 102: Soil Properties Cultivated Plants: Lecture 15 [Teresa Koenig] Slide #: 1 Slide Title: Intro Information Slide Title: Lecture 15 Soil Properties Speaker: Teresa Koenig Created by: Teresa Koenig, Kim Kidwell Music Slide #: 2 Slide Title: Slide 2 [Images of different soils] Soil Properties In this section, we will review basic soil definitions, describe common visual features found in soils, discuss soil genesis or formation, soil texture and structure in compaction. Slide #: 3 Slide Title: A. What is soil? Weathered rock and organic mater A medium to support plant growth by providing nutrients, water, air (oxygen), and physical support The foundation of all life Let s begin with a definition of soil. Wikipedia, the web-based encyclopedia states that soil is natural, composed on unconsolidated rock particles and organic materials and capable of supporting life. This definition only scratches the surface. Soils are also dynamic systems in which energy, gasses, water and other materials constantly enter, move through and exit. Soils are also teaming with life from large animals to microscopic bacteria. Across a region, field or even a small landscape, soils can vary in physical, chemical and biological processes. Finally, soils are manageable. Humans can alter either positively or negatively many soil properties. As a medium for plant growth, soil has four main roles. First, soil is a reservoir of mineral, nutrients and water. Soil also supplies air and more importantly oxygen to plant root systems. Finally, soil provides a base for the physical support of plants. The quality of soil as a medium for plant growth depends on how well soil fulfills these basic roles. Slide #: 4 Slide Title: B. Five soil-forming factors

2 1. Parent Material 2. Climate 3. Organisms 4. Topography 5. Time Soil formation is influenced by five main factors: parent material, climate, organisms, topography and time. Each factor is complex and can have several states or conditions. There are also many interactions among these factors. For example, consider the diversity of climates in terms of temperature and moisture from eastern to western Washington. Now, consider how the diversity of climates will influence the organism or vegetation factor. We will briefly review each factor to help you understand their influence on soil formation. Slide #: 5 Slide Title: 1. Parent Material: Unconsolidated mineral matter lying underneath the upper soil layers. [Image of rocks] As the name implies, parent material is the material from which soil formed. It is the unconsolidated mineral matter lying underneath the upper soil layers. Slide #: 6 Slide Title: Slide 6 a. Material from which the soil above it has been formed b. Parent material is composed of rocks Rocks weather by chemical and physical processes [Image of rocky soil profile] Parent material is composed of rocks which have been weathered by physical and chemical properties. Slide #: 7 Slide Title: Chemical Weathering: 1. Carbonation: Reaction between carbon dioxide and water to form carbonic acid, which weathers minerals 2. Hydration: Addition of water to minerals, which weakens them Chemical weathering is caused by carbonation, hydration, hydrolysis and oxidation-reduction reactions. Carbonation is the reaction between carbon dioxide and water to form carbonic acid, a substance which weathers minerals. Hydration is the addition of water to minerals, weakening the minerals over time. Slide #: 8 Slide Title: Slide 8

3 3. Hydrolysis: Reaction between parent material and water, which results in the splitting of a water molecule 4. Oxidation-reduction: Reaction of parent material with oxygen to change oxidation state of elements Hydrolysis is a splitting of water molecules caused by the reaction between parent material and water. Oxidation-reduction is a reaction of parent material with oxygen to change the oxidation of elements. Slide #: 9 Slide Title: Physical Weathering 1. Temperature Changes: Cause expansion and contraction of parent material Causes cracks in rocks [Image of cracks in rock] Changes in temperature can cause expansion and contraction of parent material. This physical weathering results in cracks in rocks. Slide #: 10 Slide Title: Slide Glacial Till: Rocks embedded in glaciers scrape over other rocks as the glacier moves, grinding rocks into smaller pieces. Another form of physical weathering is the scraping of embedded rocks in glaciers over other rocks as the glacier moves. This strong movement grinds rocks into smaller pieces. Slide #: 11 Slide Title: Slide Moving water: Carries rocks of varying sizes which collide and break into smaller particles. Moving water carries rocks of varying sizes, which collide and break into smaller particles. This is another example of physical weathering. Slide #: 12 Slide Title: Climate: Affects the rate of soil formation and the type of soil that is formed. Climate also affects the rate of soil formation and type of soil that is formed. Slide #: 13 Slide Title: Slide 13

4 a. Rate: affected by moisture, humidity, frost, heat, wind erosion and sunlight [Image of rocky soil profile] The rate of soil formation is affected by moisture, humidity, frost, heat, wind erosion and sunlight. Slide #: 14 Slide Title: Slide 14 b. Type: Influenced by the type of vegetation that grows in the soil [Image of rocks] [Image of soil profile under grassland] The type of soils formed is influenced by the type of vegetation that grows in the soil. Slide #: 15 Slide Title: 3. Organisms a. Highly influenced by climate, which influences the type and amount of vegetation produced. b. Grasses deposit organic matter (OM) in the soil and on the surface; trees deposit OM mainly on the surface (litter layer). Organisms are highly influenced by climate, which influences the type and amount of vegetation produced. Grasses deposit organic matter in the soil and on the surface. Trees deposit organic matter mainly on the surface called the litter layer. Slide #: 16 Slide Title: Slide 16 c. Microorganisms and earthworms break down OM and mix this with the soil. d. Amount of OM present is dependent on the difference between the accumulation and decomposition of OM being deposited. Microorganisms and earthworms break down organic matter and mix this with the soil. The amount of organic matter present depends on the difference between the accumulation and decomposition of organic matter being deposited. Slide #: 17 Slide Title: 4. Topography: Slope Characteristics Affects soil formation process in two ways: a. Determines the erosion rate and thus the depth of soil b. Modifies the climate Determines patterns and rates of drainage, which influences moisture levels. Aspect influences temperature.

5 The fourth factor influencing soil formation is topography. It affects soil formation in two ways. The topography determines rate of erosion and thus the depth of soil and it modifies the climate by determining the patterns and rates of drainage which influence moisture levels. Slide #: 18 Slide Title: 5. Time: Soil formation is a slow but continuous process. a. Rate is affected by the nature (chemical composition) of the parent material and the intensity of the weathering. Time is a final factor we will discuss. Soil formation is a slow but continuous process. The rate of formation is affected by the chemical composition of the parent material and the intensity of the weathering. Slide #: 19 Slide Title: b. Soil Profile A vertical cross section of the soil showing the horizontal layers, which are called horizons. [Image of a soil profile featuring two different horizons] Soils commonly vary with depth and horizontal layers called horizons. A soil profile includes all the horizons from the surface down to the bedrock or other material from which the soil formed. The horizons are given letter designations beginning with A or O for organic on the surface followed by E, B and /or C horizons below. Top soil is the A horizon and subsoil, the remaining horizons below A. Slide #: 20 Slide Title: Slide 20 Characteristics of soil profiles: 1. Older soils have more defined profiles, often with more horizons 2. Zone of leaching: Upper layers of a soil profile are washed frequently as water moves through them. They are usually higher in OM due to the presence of plant roots, thus they are darker in color. A soil profile may take thousands or even tens of thousands of years to form. This is important to keep in mind when you want to alter major soil properties in an afternoon of gardening or even a single growing season. Generally older soils are more developed with more horizons and complex features within the profile. This is not always the case however since soils in very cold or dry regions develop at a slower pace than soils in warmer, wetter regions. The upper layers of a soil profile known as the zone of leaching are washed frequently as water moves through them. They are usually higher in organic matter due to the presence of plant roots, thus they are darker in coor.

6 Slide #: 21 Slide Title: Slide Zone of accumulation: Subsoil layers are zones of accumulation of materials transported from the upper layers 4. Parent material is found below the subsoil Subsoil layers are zones of accumulation of materials transported from the upper layers. The plant material is found below the subsoil. Slide #: 22 Slide Title: Slide Characteristics of soil profiles: Give us a historical record of past climate Are used to classify soils and determine uses and management practices Soil profiles information are important because they give us a historical glimpse of the past climate. They tell us about soil depth and potential productivity of an area and suitable limitations on soil use. Soil profiles also give us information about physical properties such as water retention and drainage as well as chemical properties like ph and salinity. Slide #: 23 Slide Title: C. Soil Composition 1. Mineral matter: 40% 2. Organic matter: 10% 3. Air*:25% 4. Water*: 25% *Water and air proportions vary with conditions. In water saturated soils, air % decreases. One convenient way to think about soils is on the basis of their composition. The composition and percent by volume of an ideal or textbook soil contained 40 percent soil mineral particles, 10 percent organic matter, 25 percent air and 25 percent water. The ideal soil is composed of only 50 percent solid material by volume. Collectively, the air and water volume is called pore space and together makes up the remaining 50 percent of the soil volume. Thus soil is a very porous medium. The percentages between the solid and pore space in soils can shift if soil is compacted. This has significant implications for plant growth since compaction reduces pore space capable of containing air or water. The percentages between the air and water components are also dynamic and will shift as rain or irrigation events occur. If soil pores are filled with water for an extended period of time, plant roots have limited access to oxygen resulting in increased incidence of disease and other growth

7 problems. Slide #: 24 Slide Title: D. Soil Texture: The percentage (by weight) of sand, silt and clay-sized particles in a soil. Soil texture is the percentage by weight of sand, silt and clay-sized particles in the soil. Slide #: 25 Slide Title: Slide Clay is the smallest: very fine (<0.002 mm in diameter) 2. Silt is intermediate in size (0.002 to 0.05 mm in diameter) 3. Sand is the largest (>0.05mm in diameter) Clay particles are the smallest. Silk is the intermediate and sand is the largest with particles that are greater than.05 millimeters in diameter. Slide #: 26 Slide Title: 4. Loam: Mixture of all three particle sizes: - 40% Sand - 40% Silt - 20% Clay A loam soil is a mixture of all three particle sizes. An example of a loam soil is one that is 40 percent sand, 40 percent silt and 20 percent clay. Slide #: 27 Slide Title: Soil Triangle [Diagram of soil texture triangle] A soil texture triangle is used to categorize the texture class of a soil. The sides of the soil triangle are scaled for the percentages of sand, silt and clay. Clay percentages are read from bottom left to the top of the triangle. Silt is read from the top to the lower right of the triangle and sand, from right to left across the bottom of the triangle. The intersection of the three sizes on the triangle gives the texture class of the particular soil. So, for example, if you take our soil from the previous slide, which was 20 percent clay, 40 percent silt and 40 percent sand, it falls in the loam class on this soil texture triangle. Slide #: 28 Slide Title: Slide Course: main component: sand 2. Medium: main component: silt (Sandy loams, silty clay loams)

8 3. Fine: main component: clay If you have a course soil, the main component is sand. For a medium soil, the main component is silt and a fine textured soil is composed mainly of clay particles. Slide #: 29 Slide Title: The Importance of Particle Size [Diagram depicting water and air movement through sand particles] [Diagram depicting water and air movement through clay particles] The particle size has a large impact on water flow through the soil. Water and air flow runs freely through the sand particles on the left. It is much more difficult for water to flow through the small clay particles however on the right hand side. Slide #: 30 Slide Title: Slide 30 a. Sand has large pore spaces, so water runs through it rapidly. b. Clay has very small pores, so water won t penetrate; runs off of the surface. Once wet, clay retains excessive amounts of water. c. Silt has intermediate water retention, but it isn t as good as a loam. Sand has large pore spaces, so water runs through it rapidly. Clay has very small pores, so water won t penetrate; instead it runs off of the surface. However, once wet, the clay soil retains excessive amounts of water, which could be problematic in a field situation. Silt has intermediate water retention, but it isn t as good as a loam. Slide #: 31 Slide Title: Soil Texture Influences Water intake (infiltration) rates Water storage Drainage Ease of tillage Aeration (gas exchange) Nutrient retention and soil fertility It is important to know and understand the soil texture of your field or garden soil because it influences water infiltration rates, water storage, drainage, ease of tillage, aeration, and nutrient retention and soil fertility. Slide #: 32 Slide Title: Texture and key physical properties in soil A loam soil is optimum because it has characteristics of each particle size without being

9 dominated by one [Table of five different soil types ranking them on their plant available water, gas exchange and drainage capacities] If we look at some of these characteristics in five different soil types, a sandy soil, sandy loam soil, silt loam, clay loam and clay soil, we see that a loam soil is optimum because it has characteristics of each particle size without being dominated by one. The silt loam will have adequate amount of water, gas exchange and drainage. A sandy loam would allow for increased gas exchange and drainage, but would lack plant available water. In contrast, a clay soil would have high water holding capacity for the plant, but allow for little gas exchange or drainage. Slide #: 33 Slide Title: E. Soil structure The combination of sand, silt and clay (with organic matter) into secondary particles called aggregates [Diagram of soil structure] Soil structure is a combination of sand, silt and clay with organic matter into secondary particles called aggregates. Slide #: 34 Slide Title: Structure [Image of good structured loam soil] [Image of clay soil with no structure] The soil at the top of this slide has good structure and adequate amounts of organic matter. The soil pictured on the lower right has poor soil structure. Slide #: 35 Slide Title: Soil structure results from: a. Climate: Weathers the soil b. Plants: Add roots and residue that decompose and glue soil particles together. Soil structure results from climate weathering the soil over time. The plants supply the roots and residue that decompose and glue soil particles together. Slide #: 36 Slide Title: 1. Type of structural aggregates in soil affects: a. Soil pore size b. Water-holding capacity c. Water-infiltration rate

10 d. Soil permeability to water and air e. Soil compaction The type of structural aggregates in soil affects its pore size, water holding capacity, water infiltration rate, soil permeability to water and air and soil compaction. Slide #: 37 Slide Title: 2. Unlike soil texture, soil structure can be changed by manipulating the soil. Unlike soil texture, soil structure can be changed by manipulating the soil. Slide #: 38 Slide Title: Slide 38 a. Amendments: Materials incorporated into the soil: grass clippings, manure b. Disruption: Plowing, compaction with equipment, tillage These changes in soil structures may the results of amendments such as grass clipping or manure or disrupting the soil by plowing, compaction with equipment or tillage. Slide #: 39 Slide Title: Compaction Destroys soil structure Seals off soil surface o Water runs off instead of into soil drought o Air can t enter or escape soil suffocation o Roots can t penetrate the soil physical barrier Stress death of plants [Image of a pathway through grass] Compaction destroys soil structure by sealing off the soil surface. When this occurs, water runs off instead of into the soil causing drought. Air cannot enter or escape the soil so plants suffocate and roots cannot penetrate the soil producing a physical barrier. All of these problems cause plant stress and eventually death of the plant.

Unit 1 Lesson 5 Soil Formation. Copyright Houghton Mifflin Harcourt Publishing Company

Unit 1 Lesson 5 Soil Formation. Copyright Houghton Mifflin Harcourt Publishing Company The Dirt on Soil What causes soil to form? Soil is a loose mixture of rock fragments, organic matter, water, and air that can support the growth of vegetation. The first step in soil formation is the weathering

More information

5.1 Introduction to Soil Systems IB ESS Mrs. Page

5.1 Introduction to Soil Systems IB ESS Mrs. Page 5.1 Introduction to Soil Systems IB ESS Mrs. Page 2015-2016 I Am Soil Thinking Routine: See, Think, Wonder Look at the following images. For each image write down what you see Then write down what you

More information

Soil characteristics that influence nitrogen and water management

Soil characteristics that influence nitrogen and water management Section C Soil characteristics that influence nitrogen and water management Soil characteristics vary across the landscape Soils vary from one field to another, and often within the same field. Soil differences

More information

Soil Resources. Soil Horizons

Soil Resources. Soil Horizons Soil Resources Soil Uppermost layer of earth s crust that supports plants, animals and microbes Soil Forming Factors Parent Material Time Climate Organisms Topography Soil Composition Mineral Particles

More information

Soil Texture and Structure. Chris Thoreau February 24, 2012

Soil Texture and Structure. Chris Thoreau February 24, 2012 Soil Texture and Structure Chris Thoreau February 24, 2012 Soil texture refers to the relative amount of sand, silt, and clay found in a soil The mixture of these components affects the feel of the soil

More information

Loam: About 40% sand, 40% silt, 20% clay. Mixture of pore sizes to balance water retention and aeration. Considered the best soil for growing crops.

Loam: About 40% sand, 40% silt, 20% clay. Mixture of pore sizes to balance water retention and aeration. Considered the best soil for growing crops. Soil Characteristics Soil is formed from a combination of two Primary sources: Weathering of Parent Rock ( ) = material introduced by plants, animals, and decomposers Minor sources: Nutrients incorporated

More information

Why do soils differ across the landscape?

Why do soils differ across the landscape? Today s Objectives: Elements of soil formation Describe important soil physical & chemical properties Describe the ability to use and interpret soil survey information (printed and digital) List some site

More information

1. The Nature of Soils and Soil Fertility

1. The Nature of Soils and Soil Fertility 1. The Nature of Soils and Soil Fertility The Ontario Soil Fertility Handbook contains information on the fundamental concepts of soil fertility. If you have ever wondered how nutrients make their way

More information

Soil is. Pieces of rock Minerals Decaying organic matter Water Air Living organisms All mixed together!

Soil is. Pieces of rock Minerals Decaying organic matter Water Air Living organisms All mixed together! Soil is. Pieces of rock Minerals Decaying organic matter Water Air Living organisms All mixed together! Soil Horizons the layers of soil O-horizon: the surface litter. Mainly black or brown A-horizon:

More information

4/23/2018. Soil John Wiley & Sons, Inc. All rights reserved. Lecture 14

4/23/2018. Soil John Wiley & Sons, Inc. All rights reserved. Lecture 14 Lecture 14 Soil Lecture 14 1. The Soil System 2. Soil Properties and Major Soil Types 3. Environmental Problems Related to Soil 4. Soil Conservation and Regeneration 1 The Soil System Soil Uppermost layer

More information

The Nature of Soil Soil Conservation Sustainable Ag.

The Nature of Soil Soil Conservation Sustainable Ag. Chapter 6 & 7 The Nature of Soil Soil Conservation Sustainable Ag. Climate Soil Forming Factors Parent material Organisms Topography Time Value of Soil Soil is under appreciated Condition of soil affects

More information

Class 1: Introduction to Soil Formation, Texture and Structure. Chris Thoreau February 11, 2012

Class 1: Introduction to Soil Formation, Texture and Structure. Chris Thoreau February 11, 2012 Class 1: Introduction to Soil Formation, Texture and Structure Chris Thoreau February 11, 2012 Soil is a dynamic composition of: Minerals Water and its solutions Organic matter (detritus) Air and other

More information

Basic Soil Science. Fundamentals of Nutrient Management. Melissa L. Wilson

Basic Soil Science. Fundamentals of Nutrient Management. Melissa L. Wilson Basic Soil Science Fundamentals of Nutrient Management Melissa L. Wilson Department of Environmental Science & Technology Ag Nutrient Management Program University of Maryland, College Park Photo credit:

More information

Soil Management: the basis of sustainable agriculture

Soil Management: the basis of sustainable agriculture Soil Management: the basis of sustainable agriculture FAB-465 Lecture 11 Lecture Outline Soil Formation Soil Structure/Texture Indicators of Soil Health or Fertility Soil Conservation Practices 1 Soil

More information

Overview of Chapter 14

Overview of Chapter 14 14 Soil Resources Overview of Chapter 14 The Soil System Soil Properties and Major Soil Types Environmental Problems Related to Soil Soil Conservation and Regeneration Soil Uppermost layer of earth s crust

More information

2012 FINAL SOILS AREA 2 Envirothon Questions Answer KEY

2012 FINAL SOILS AREA 2 Envirothon Questions Answer KEY 2012 FINAL SOILS AREA 2 Envirothon Questions Answer KEY Questions 1-6 to be answered at the soil pit: 1. Soil scientists categorize soils by drainage classes. What is the drainage class of the soil at

More information

Soil 1/18/2012. Soils, Nutrients and Fertilizers Part I. Soil Profile

Soil 1/18/2012. Soils, Nutrients and Fertilizers Part I. Soil Profile Soils, Nutrients and Fertilizers Part I Handouts: Soil Texture Triangle ph Nutrient Availability Soil Diverse combination of weathered rock fragments and minerals, with decaying remains of plants and animals

More information

EXAMPLE Point A: Sandy Loam: 65% Sand _ 20% Silt _ 15% Clay. Point B: %Sand % Silt % Clay. Point C: %Sand % Silt % Clay. Point D: %Sand % Silt % Clay

EXAMPLE Point A: Sandy Loam: 65% Sand _ 20% Silt _ 15% Clay. Point B: %Sand % Silt % Clay. Point C: %Sand % Silt % Clay. Point D: %Sand % Silt % Clay SOIL TEXTURE Refers to proportions of sand, silt and clay size particles. These proportions determine water infiltration rates, permeability rates, and water holding rates. Using a soil texture triangle.

More information

Eco new farmers. Module 2 Soil and Nutrient Cycling. Section 1 Soils and soil fertility

Eco new farmers. Module 2 Soil and Nutrient Cycling. Section 1 Soils and soil fertility Eco new farmers Module 2 Soil and Nutrient Cycling Section 1 Soils and soil fertility Module 2 Soil and Nutrient Cycling Section 1 - Soils and soil fertility www.econewfarmers.eu 1. Introduction You will

More information

There are different types of weathering weathering and weathering. Both types work together to change Earth s surface.

There are different types of weathering weathering and weathering. Both types work together to change Earth s surface. Weathering effects Classifying Sediment The surface processes that break down rock are called. Weathering breaks rock into smaller and smaller pieces. Tiny moss plants, earthworms, wind, rain, and even

More information

Chapter 15 Soil Resources

Chapter 15 Soil Resources Chapter 15 Soil Resources Overview of Chapter 15 What is Soil? Soil Horizons Nutrient Cycling Soil Properties and Major Soil Types Soil Problems Soil Conservation and Regeneration Soil Uppermost layer

More information

WEATHERING AND SOIL FORMATION. 8th Grade- Mr. Stelma

WEATHERING AND SOIL FORMATION. 8th Grade- Mr. Stelma WEATHERING AND SOIL FORMATION 8th Grade- Mr. Stelma WEATHERING EFFECTS The surface processes that break down rock are called weathering. Weathering breaks rock into smaller and smaller pieces. Tiny moss

More information

Unit 5: Soil - Stages of Soil formation

Unit 5: Soil - Stages of Soil formation Biology Form 3 Page 68 Ms. R. Buttigieg Unit 5: Soil - Stages of Soil formation Soil is the layer of material covering parts of the land, the home of many organisms and the area from which land plants

More information

EDULABZ. Ans. (b) 7. The soft, porous layer with a good water-retaining capacity forms the

EDULABZ. Ans. (b) 7. The soft, porous layer with a good water-retaining capacity forms the 3 SOIL I. Multiple choice questions: Tick ( ) the correct choice. 1. The process of soil formation is called (a) conservation (b) weathering (c) erosion (d) none Ans. (b) 2. Soil profile consists of (a)

More information

Introduction to Environmental Science. Soil Characteristics. Chapter 11 Soil

Introduction to Environmental Science. Soil Characteristics. Chapter 11 Soil Chapter 11 Soil Soil Characteristics It s more than dirt Most soils are 100s of years old Weathering breaks down parent rock Soil Separates (particle types) Sand (largest) Silt Clay (smallest) Plants contribute

More information

2014 Iowa FFA Soil Judging CDE Exam

2014 Iowa FFA Soil Judging CDE Exam 2014 Iowa FFA Soil Judging CDE Exam 1. Landscape position is one aspect of evaluating the surface features of a certain tract of land. Identifying the correct landscape position will indicate: a. If the

More information

Objectives: Students will learn about the types and textures of soil within a soil profile.

Objectives: Students will learn about the types and textures of soil within a soil profile. Objectives: Students will learn about the types and textures of soil within a soil profile. Materials: Soil profile pictures with description (mounted with Velcro) Soil profile poster board Soil Word Scramble

More information

27/01/2017. This event is being run by SAC Consulting. What is Soil?

27/01/2017. This event is being run by SAC Consulting. What is Soil? This event is being run by SAC Consulting What is Soil? 1 Soil Texture It describes the physical composition of the soil % of sand, silt and clay Refers to the mineral fragments of the soil only water

More information

Bell Ringer. d) Erosion e) Decomposition of organic compounds

Bell Ringer. d) Erosion e) Decomposition of organic compounds Bell Ringer 1) A rock exposed to high winds, over a long period of time, loses half of its original size. This is an example of a) Physical weathering b) Chemical weathering c) Biological weathering d)

More information

Soil Notes. General Soil Information

Soil Notes. General Soil Information Soil Notes General Soil Information Definition Soil relatively thin surface layer of the Earth s crust consisting of mineral and organic matter that is affected by agents such as weather, wind, water,

More information

Factoids on SC soils. Soils. What is Soil? Variability of soils in your yard. Soil Components. Soil Tilth 6/23/14

Factoids on SC soils. Soils. What is Soil? Variability of soils in your yard. Soil Components. Soil Tilth 6/23/14 Factoids on SC soils Soils Managing Soils Over 100 different soil types Soil type covering largest areas 7.0% Ben Lomond Complex 50-70% slope 5.6% Lompoc Felton Complex 50-75% slope 5.8% Lompoc Felton

More information

Lecture 3: Soil Microclimatology

Lecture 3: Soil Microclimatology Lecture 3: Soil Microclimatology Introduction to Soils Heat Transfer Through Soils Water Transfer Through Soils What is a Soil? Soil is a complex mixture of mineral matter, organic matter and living organisms

More information

Soil Geography Notes JC-Learn. JC-Learn. Geography Notes Soil. 1 P a g e

Soil Geography Notes JC-Learn. JC-Learn. Geography Notes Soil. 1 P a g e JC-Learn Geography Notes Soil 1 P a g e Soil Soil is the thin covering of loose material that makes up the outermost layer of our planet. It is a living thing and a rich natural resource. Plants need soil

More information

Soil Damage From Compaction

Soil Damage From Compaction Soil Damage From Compaction by Dr. Kim D. Coder, University of Georgia July 000 Having reviewed the primary means by which soils become compacted, the results of compaction can be estimated for tree and

More information

CCA Exam Prep Intro to Soil & Water

CCA Exam Prep Intro to Soil & Water CCA Exam Prep Intro to Soil & Water Franz Niederholzer, UCCE Farm Advisor Colusa/Sutter/Yuba Counties fjniederholzer@ucanr.edu and Sharon Benes, Professor CSU, Fresno Physical soil properties Texture Structure

More information

The GEOGRAPHY of SOILS. Physical Geography (Geog. 300) Prof. Hugh Howard American River College

The GEOGRAPHY of SOILS. Physical Geography (Geog. 300) Prof. Hugh Howard American River College The GEOGRAPHY of SOILS Physical Geography (Geog. 300) Prof. Hugh Howard American River College SOIL and SOIL- FORMING FACTORS SOIL and FORMING FACTORS Soil Natural surface layer of Earth Composed of mineral

More information

Alluvium Bedrock Chemical Weathering Climate Glacial Till Loess Native Vegetation

Alluvium Bedrock Chemical Weathering Climate Glacial Till Loess Native Vegetation 1 Alluvium Bedrock Chemical Weathering Climate Glacial Till Loess Native Vegetation Organic Matter Outwash Parent Material Physical Weathering Prairie Soils Timber Soils Topography 2 There are five primary

More information

Secondary Consumer (Carnivore or Omnivore)

Secondary Consumer (Carnivore or Omnivore) Chapter 8 - Water and Soil Conservation Benefits of Living Organisms for Water and Soil 1. plants break fall of rain and reduce damage to the soil 2. plant materials on the soil provide a rain absorbing

More information

TEXTBOOK QUESTIONS AND THEIR ANSWERS. Q.1. Can the soil from a field be used to make toys?

TEXTBOOK QUESTIONS AND THEIR ANSWERS. Q.1. Can the soil from a field be used to make toys? 9 SOIL TEXTBOOK QUESTIONS AND THEIR ANSWERS Q.1. Can the soil from a field be used to make toys? Ans. No, soil from a field cannot be used to make toys. In order to make toys the soil should be clayey.

More information

2016 Iowa FFA Soils Evaluation CDE Exam

2016 Iowa FFA Soils Evaluation CDE Exam 2016 Iowa FFA Soils Evaluation CDE Exam 1. Which of the following is true regarding soil horizons? a. A horizon is darker in color and has more organic matter b. B horizon is darker in color and has more

More information

2018 Iowa FFA Soil Judging CDE Exam 1. Landscape positions characterizes the location of the soil on the landscape and identifies potential risks.

2018 Iowa FFA Soil Judging CDE Exam 1. Landscape positions characterizes the location of the soil on the landscape and identifies potential risks. 2018 Iowa FFA Soil Judging CDE Exam 1. Landscape positions characterizes the location of the soil on the landscape and identifies potential risks. Which landscape position is considered the floodplain

More information

List of Equipment, Tools, Supplies, and Facilities:

List of Equipment, Tools, Supplies, and Facilities: Unit A: Principles of Soil Lesson 2: Overview of Soil Science Student Learning Objectives: Instruction in this lesson should result in the students achieving the following objectives: 1. Understand the

More information

Soil. Guiding Question: What is soil?

Soil. Guiding Question: What is soil? LESSON 1 Soil Guiding Question: What is soil? Explain three processes by which soil forms. Describe the horizons that make up a soil profile. List the four characteristics used to classify soil. Reading

More information

Soil Interpretations Erosion and Sedimentation Control Planning and Design Workshop

Soil Interpretations Erosion and Sedimentation Control Planning and Design Workshop Soil Interpretations Erosion and Sedimentation Control Planning and Design Workshop Presented by Richard Brooks Presentation prepared by Kristin May Resource Soil Scientists USDA-Natural Resources Conservation

More information

SOIL SCIENCE 101. By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2015

SOIL SCIENCE 101. By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2015 SOIL SCIENCE 101 By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2015 dawn.pettinelli@uconn.edu Soil is the collection of natural bodies in the earth s surface, in places modified

More information

Soil Texture = %Sand, Silt & Clay in a soil.

Soil Texture = %Sand, Silt & Clay in a soil. Soils Soil Texture = %Sand, Silt & Clay in a soil. Soil texture is the single most important physical property of the soil. Knowing the soil texture alone will provide information about: 1) water flow

More information

2016 Area 3 Envirothon Muskingum County Soils Test ANSWER KEY

2016 Area 3 Envirothon Muskingum County Soils Test ANSWER KEY 2016 Area 3 Envirothon Muskingum County Soils Test ANSWER KEY 1. The majority of the bedrock in Muskingum County is. a. sedimentary bedrock b. glacial bedrock c. igneous bedrock d. metamorphic bedrock

More information

Iowa FFA Soil Career Development Event 2008

Iowa FFA Soil Career Development Event 2008 Iowa FFA Soil Career Development Event 2008 1. In Iowa, corn suitability ratings for soil mapping units specifies a. natural weather conditions b. surface and subsurface drainage installed where needed

More information

EARTH SCIENCE CONCEPTS -Geologic time scale

EARTH SCIENCE CONCEPTS -Geologic time scale EARTH SCIENCE CONCEPTS -Geologic time scale -Plate Tectonics -Earthquakes *result of vibrations (often due to plate movement) deep in the Earth that release energy *often occur at transform boundaries

More information

Name. There are three main types of soils called textures. They are: sand, silt, and clay. Sand has the largest particles and clay has the smallest.

Name. There are three main types of soils called textures. They are: sand, silt, and clay. Sand has the largest particles and clay has the smallest. Introduction Name What Soil is: Soil is a natural body made up of minerals (rock), organic (living and dead) materials, air, and water. Soil has living and dead parts in it. There are three main types

More information

ASTOUNDING as it may seem, a shovelful of soil

ASTOUNDING as it may seem, a shovelful of soil The Nature of Soil ASTOUNDING as it may seem, a shovelful of soil holds more living things than all the humans that have ever been born. Living things are just one component of soil, a material undervalued

More information

1 Describe the concept of soil texture and its importance. 2 Determine the texture of a soil sample.

1 Describe the concept of soil texture and its importance. 2 Determine the texture of a soil sample. Interest Approach Provide students with various samples of soil. One sample should be nearly all sand, one nearly all clay, and one nearly all silt. Ask students to determine how the samples differ. Would

More information

List of Equipment, Tools, Supplies, and Facilities:

List of Equipment, Tools, Supplies, and Facilities: Unit A: Principles of Soil Lesson 4: Formation of Soil Student Learning Objectives: Instruction in this lesson should result in the students achieving the following objectives: 1. Identify 5 factors involved

More information

Special Assignment for Wednesday: Watch video on soil texture analysis https://youtu.be/ioyabxj767s

Special Assignment for Wednesday: Watch video on soil texture analysis https://youtu.be/ioyabxj767s Special Assignment for Wednesday: Watch video on soil texture analysis https://youtu.be/ioyabxj767s Lecture 3: Soil Physical Properties Important Physical Properties Soil Color: Most obvious physical property;

More information

2014 Envirothon Georgia Soil Study Guide

2014 Envirothon Georgia Soil Study Guide 2014 Envirothon Georgia Soil Study Guide In addition to materials in this document, 2014 Georgia Envirothon contestants are responsible for materials found in the following documents: From The Surface

More information

SOIL SCIENCE 101. By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2016

SOIL SCIENCE 101. By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2016 SOIL SCIENCE 101 By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2016 dawn.pettinelli@uconn.edu Soil is the collection of natural bodies in the earth s surface, in places modified

More information

Infiltration. Keep Water Where it Falls. Frank Franciosi Novozymes

Infiltration. Keep Water Where it Falls. Frank Franciosi Novozymes Keep Water Where it Falls Frank Franciosi Novozymes Defined refers to the movement of water into the soil layer. The rate of this movement is called the infiltration rate. If rainfall intensity is greater

More information

SOIL SCIENCE 101 FUNCTIONS OF SOIL SOIL FORMATION

SOIL SCIENCE 101 FUNCTIONS OF SOIL SOIL FORMATION SOIL SCIENCE 101 By Dawn Pettinelli UConn Soil Nutrient Analysis Lab CT Envirothon Training, 2014 dawn.pettinelli@uconn.edu FIVE CRUCIAL ECOLOGICAL ROLES OF SOILS FUNCTIONS OF SOIL Regulate water flow

More information

Soils. Living in the Environment, 15 th Edition, Miller

Soils. Living in the Environment, 15 th Edition, Miller Soils Living in the Environment, 15 th Edition, Miller Soils: Formation Soil horizons Soil profile Humus O horizon soil A horizon B horizon C horizon Regolith Bedrock soil soil Fig. 10.12, p. 220 Soil

More information

3 From Bedrock to Soil

3 From Bedrock to Soil CHAPTER 10 3 From Bedrock to Soil SECTION Weathering and Soil Formation BEFORE YOU READ After you read this section, you should be able to answer these questions: What is soil? How do the features of soil

More information

Soil Health & Assessment

Soil Health & Assessment Soil Health & Assessment National Association of Conservation Districts (NACD) Urban and Community Development Webinar Series Presented by, Eileen Miller, Soil Health Specialist USDA NRCS NJ January 15,

More information

ON LANDSCAPING, SOILS, SOIL AMENDMENTS AND PROPER SEED ESTABLISHMENT (BOTH GRASS LAWNS AND MEADOWS).

ON LANDSCAPING, SOILS, SOIL AMENDMENTS AND PROPER SEED ESTABLISHMENT (BOTH GRASS LAWNS AND MEADOWS). ON LANDSCAPING, SOILS, SOIL AMENDMENTS AND PROPER SEED ESTABLISHMENT (BOTH GRASS LAWNS AND MEADOWS). John D. Chibirka USDA-NRCS Resource Soil Scientist 1238 County Welfare Road, Suite 220 Leesport, PA

More information

Components of Soil. Humus: (a carbon sink) Dark brown or black color indicates high nitrogen content.

Components of Soil. Humus: (a carbon sink) Dark brown or black color indicates high nitrogen content. Components of Soil Humus: (a carbon sink) Dark brown or black color indicates high nitrogen content. Inorganic Soil Components: Particle Size: Clay- Very fine Silt- Fine Sand- Medium Gravel- Large Discuss

More information

OHIO STATE UNIVERSITY EXTENSION. Soil and Nutrients. OSUE Master Gardeners Mahoning County Class of Bill Snyder March 21, 2017

OHIO STATE UNIVERSITY EXTENSION. Soil and Nutrients. OSUE Master Gardeners Mahoning County Class of Bill Snyder March 21, 2017 OHIO STATE UNIVERSITY EXTENSION Soil and Nutrients OSUE Master Gardeners Mahoning County Class of 2017 Bill Snyder March 21, 2017 Soil vs DIRT Ecological Roles of Soil 1. Medium for plant growth 2. Recycling

More information

The relationship between soil (growing

The relationship between soil (growing 4 Plant, Soil and Water Relationships The relationship between soil (growing media), air, and water is one of the least understood aspects in production and maintenance of plants. As a result, a significant

More information

O horizon: the O-horizon is made up of organic material. The horizon is found at the soil surface.

O horizon: the O-horizon is made up of organic material. The horizon is found at the soil surface. A Good Dirty n Soil Lab: References: Wagner & Sanford. Environmental Science. Wiley & Sons, 2005. Molnar. Laboratory Investigations for AP* Env. Science. Peoples Ed, 2005. Soil Porosity & Permeability

More information

Soil Nutrient Management

Soil Nutrient Management 31 st May 2016 Soil Nutrient Management Christopher Johns Research Manager Northern Australia and Land Care Key Points The most basic components of soil are minerals, organic matter, water and air. Mineral

More information

Team number Page 1 of Canon Envirothon Soils Station Test. Soils and Climate Change

Team number Page 1 of Canon Envirothon Soils Station Test. Soils and Climate Change Team number Page 1 of 9 2006 Canon Envirothon Soils Station Test Soils and Climate Change There are many kinds of soil on the surface of the earth. The kind of soil that is present at a given location

More information

Soil Structure and the Physical Fertility of Soil

Soil Structure and the Physical Fertility of Soil 12 17 th December 2015 Soil Structure and the Physical Fertility of Soil Christopher Johns Research Manager Northern Australia Key Points The physical properties of soil are at least as important as the

More information

Soil is formed by various processes and originates from parent material.

Soil is formed by various processes and originates from parent material. Soils and sediments usually contain organic matter from decayed vegetation. A majority of the organic matter is humic substances. o Humic substances are naturally formed from the decomposition of vegetation.

More information

Understanding Soils. 1. What is Soil? 2. What does soil do for us?

Understanding Soils. 1. What is Soil? 2. What does soil do for us? Understanding Soils 1. What is Soil? Soil: (i) The unconsolidated mineral or organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants. (ii) The

More information

Soil Chemistry. Key Terms.

Soil Chemistry. Key Terms. Soil Chemistry Key Terms Key Terms in Soil Chemistry Buffering capacity - this is the soil's ability to resist changes in soil ph. Soils with a high buffering capacity require a great deal of amendment

More information

Section 1. Judging the soil pit (questions 1-4)

Section 1. Judging the soil pit (questions 1-4) CONNECTICUT ENVIROTHON 2009 SOILS QUESTIONS Please select the best response to the following questions. There are 25 questions; each question is worth 4 points. Section 1. Judging the soil pit (questions

More information

Homework Activity Jar Test for Soil Texture

Homework Activity Jar Test for Soil Texture Homework Activity Jar Test for Soil Texture Background: 1. What is soil? 2. What natural factors influence the formation of soil? 3. How will the depth of each horizon in your soil profile affect your

More information

Great Soil-Great Gardens I Basic Soil Science Brad Park, Rutgers University Materials developed by: Karen A. Plumley, Ph.D.

Great Soil-Great Gardens I Basic Soil Science Brad Park, Rutgers University Materials developed by: Karen A. Plumley, Ph.D. Great Soil-Great Gardens I Basic Soil Science Brad Park, Rutgers University Materials developed by: Karen A. Plumley, Ph.D. Research Director, Alliance for Low Input Sustainable Turf Soils Instructor,

More information

Soil testing Page 1. Contrary to what is widely believed, the colour of the soil reveals very little about its fertility.

Soil testing Page 1. Contrary to what is widely believed, the colour of the soil reveals very little about its fertility. Soil testing Page 1 Soil The Basics Soil is the uppermost surface of the earth, which has been slowly transformed by decomposition due to the effects of weather, vegetation and human activities. The parent

More information

Lesson 1: Recognizing the Characteristics of Soils and the Soil Requirements for Fruit and Nut Crops

Lesson 1: Recognizing the Characteristics of Soils and the Soil Requirements for Fruit and Nut Crops Lesson 1: Recognizing the Characteristics of Soils and the Soil Requirements for Fruit and Nut Crops 1 Mineral matter Organic matter Pore spaces Tilth Hygroscopic water Soil aeration 22 I. Soil is a layer

More information

Soil Physical Properties

Soil Physical Properties Soil Physical Properties ESRM 311 SEFS 507 Some examples of mineral soil development eg, Rock Weathering Types of Weathering Physical/Mechanical Chemical Biological Photo by D Vogt CO 2 + H 2 O H 2 CO

More information

DIRT! APES Laboratory Activity

DIRT! APES Laboratory Activity Name: Part I: Soil Texture DIRT! APES Laboratory Activity Can one determine the texture of soil by examining the particles found in a particular sample? The purpose of this activity is to determine the

More information

Soil Characteristics. Soil Science 101

Soil Characteristics. Soil Science 101 Craig R. Miller Parks & Open Space Manager www.cpnmd.org Soil Characteristics There are several ways to describe soil. Understanding the characteristics of soil helps the gardener amend soil. Urban soil

More information

Title: Lecture 16 Soil Water and Nutrients Speaker: Teresa Koenig Created by: Teresa Koenig, Kim Kidwell. online.wsu.edu

Title: Lecture 16 Soil Water and Nutrients Speaker: Teresa Koenig Created by: Teresa Koenig, Kim Kidwell. online.wsu.edu Title: Lecture 16 Soil Water and Nutrients Speaker: Teresa Koenig Created by: Teresa Koenig, Kim Kidwell online.wsu.edu Photos courtesy of Rich Koenig Photos courtesy of USDA NRCS Soil Water and Nutrients

More information

Soil Formation. 6.E.2.3 Explain how the formation of soil is related to the parent rock type and the environment in which it develops.

Soil Formation. 6.E.2.3 Explain how the formation of soil is related to the parent rock type and the environment in which it develops. Soil Formation 6.E.2.3 Explain how the formation of soil is related to the parent rock type and the environment in which it develops. What is soil? A loose mixture of weathered rock, organic material,

More information

Soil Horizons cont. Oa- highly decomposed Oi-undecomposed

Soil Horizons cont. Oa- highly decomposed Oi-undecomposed Soils Soil Basics Soil Horizons Soil Horizons cont. O Horizon: Or organic layer Organic layer of decomposing plant and animal tissue. Wooded upland areas have thin O horizons Wetlands may have thick O

More information

Learning Objectives Part 1. Chapter 4 Soil Physical Properties. Soil Physical Properties. Color. Physical properties part 1

Learning Objectives Part 1. Chapter 4 Soil Physical Properties. Soil Physical Properties. Color. Physical properties part 1 Learning Objectives Part 1 Chapter 4 Soil Physical Properties Know what color tells you about a soil Describe the concept of soil texture and its importance Use the textural triangle to determine a soil

More information

DO YOU KNOW YOUR SOILS? (Rev. 10/11)

DO YOU KNOW YOUR SOILS? (Rev. 10/11) DO YOU KNOW YOUR SOILS? (Rev. 10/11) Circle all the correct answers. 1. What is the layer normally present on the surface of the soil in cropped fields? a. O c. Ap e. B g. R b. A d. E f. C 2. Available

More information

Soil Quality / Understanding Soil Health what are we missing?

Soil Quality / Understanding Soil Health what are we missing? Soil Quality / Understanding Soil Health what are we missing? Soil Quality Test Kit Clarence Chavez Soil Scientist The USDA is an Equal Opportunity Provider and Employer Soils are not machines: It s an

More information

Do Now: From which materials do you think soil is made? Are all soils the same? Think of some ways that they are different?

Do Now: From which materials do you think soil is made? Are all soils the same? Think of some ways that they are different? Do Now: From which materials do you think soil is made? Are all soils the same? Think of some ways that they are different? Basics Soil is a major component of the biosphere It contains solids, liquids

More information

Building Healthy Soils. Mary Hagedorn

Building Healthy Soils. Mary Hagedorn Building Healthy Soils Mary Hagedorn Please Silence Cell Phone Thank you! Our Vision: A healthier world through environmental stewardship. Our Mission: To support the University of Maryland Extension

More information

LAB 12: Soils. Name School. Patrich Physical Geography Lab 1

LAB 12: Soils. Name School. Patrich Physical Geography Lab 1 Name School LAB 12: Soils Soil is a mixture of weathered rock & organic matter that usually covers bedrock (solid rock that underlies all soil). Both chemical & mechanical processes are involved in the

More information

Soil compaction Soil Colour

Soil compaction Soil Colour Soil compaction Soil compaction is defined as the method of mechanically increasing the density of soil. In construction, this is a significant part of the building process. If performed improperly, settlement

More information

Science Grade : 9 Term-3/Final Exam Revision Sheet

Science Grade : 9 Term-3/Final Exam Revision Sheet Science Grade : 9 Term-3/Final Exam Revision Sheet Exam Date:Sunday 3/6/2018 CCS:ES.1c,1d,1e,1g,1k Chapter(10): Weathering and soil formation Sections:2,3,4 Textbook pages 284 to 297 Chapter(10):Weathering

More information

Sandy Soils. Sand. Silt. Sandy soils. Silty soils. Wind blown and alluvial parent materials. Low water holding capacity

Sandy Soils. Sand. Silt. Sandy soils. Silty soils. Wind blown and alluvial parent materials. Low water holding capacity Sand Large particles you can see Large spaces between particles Rapid water flow Non cohesive Small surface area Low water holding capacity Susceptible to drought Small surface area Low CEC Infertile Easily

More information

Chapter 2 Section 2 You will learn about the formation of soil.

Chapter 2 Section 2 You will learn about the formation of soil. Chapter 2 Section 2 You will learn about the formation of soil. Soil is found in many places backyards, empty city lots, farm fields, gardens, and forests. What is soil and where does it come from? Soil

More information

Your Logo Here. Recycle with us today! Grow with us tomorrow! Kevin Anderson

Your Logo Here. Recycle with us today! Grow with us tomorrow! Kevin Anderson Your Logo Here Recycle with us today! Grow with us tomorrow! Kevin Anderson www.missouriorganic.com 816-483-0908 A Problem???? 2 What Happens to Soils and Soil Functions as We Turn Forests into Cities?

More information

Unit 6 Lesson 3 What Is Soil? Copyright Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 What Is Soil? Copyright Houghton Mifflin Harcourt Publishing Company Soil Is Not Just Dirt When you are in a forest or garden, what is under your feet? Below the sticks, rocks, and plants, there is soil. Soil Is Not Just Dirt What is soil? What are parts of soil? Soil is

More information

Soils Soil is one of the world's most important natural resources. Together with air and water it is the basis for life on planet earth. Most of our food depends on soil - it is where we find the plants

More information

Soils 101: A practical approach. Kevin Marini UCCE Placer/Nevada Counties

Soils 101: A practical approach. Kevin Marini UCCE Placer/Nevada Counties Soils 101: A practical approach Kevin Marini UCCE Placer/Nevada Counties Soils 101: agenda Soil Basics Soil Fertility (how plants and soil interact) Soil Food Web Fertilizers/Amendments Soils 101: a Quote

More information

2017 Iowa FFA Soil Judging CDE Exam

2017 Iowa FFA Soil Judging CDE Exam 2017 Iowa FFA Soil Judging CDE Exam 1. Landscape positions vary in soil composition and makeup. What landscape position would be characterized by having strata and lenses of different textures in the profile:

More information

URBAN SOILS & SEATTLE EXAMPLES

URBAN SOILS & SEATTLE EXAMPLES Class Results - Mystery Soil #1 14 12 10 8 6 4 2 0 Sandy Clay Loam Sandy Loam Silty Loam Class Results - Mystery Soil #2 6 5 4 3 2 1 0 Silty Clay Clay Loam Sandy Sandy Silty Sandy Silty Loamy Loam Clay

More information

Lawn and Yard Care Choices

Lawn and Yard Care Choices SYSTEM (n) Interacting and interdependent parts that form a whole. Whether you choose an exceptional lawn, low input lawn, conversion of lawn, or a combination of types Lawn and Yard Care Choices Thank

More information