Soil Texture
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Basic Soil Science W
Basic Soil Science W. Lee Daniels See http://pubs.ext.vt.edu/430/430-350/430-350_pdf.pdf for more information on basic soils! [email protected]; 540-231-7175 http://www.cses.vt.edu/revegetation/ Well weathered A Horizon -- Topsoil (red, clayey) soil from the Piedmont of Virginia. This soil has formed from B Horizon - Subsoil long term weathering of granite into soil like materials. C Horizon (deeper) Native Forest Soil Leaf litter and roots (> 5 T/Ac/year are “bio- processed” to form humus, which is the dark black material seen in this topsoil layer. In the process, nutrients and energy are released to plant uptake and the higher food chain. These are the “natural soil cycles” that we attempt to manage today. Soil Profiles Soil profiles are two-dimensional slices or exposures of soils like we can view from a road cut or a soil pit. Soil profiles reveal soil horizons, which are fundamental genetic layers, weathered into underlying parent materials, in response to leaching and organic matter decomposition. Fig. 1.12 -- Soils develop horizons due to the combined process of (1) organic matter deposition and decomposition and (2) illuviation of clays, oxides and other mobile compounds downward with the wetting front. In moist environments (e.g. Virginia) free salts (Cl and SO4 ) are leached completely out of the profile, but they accumulate in desert soils. Master Horizons O A • O horizon E • A horizon • E horizon B • B horizon • C horizon C • R horizon R Master Horizons • O horizon o predominantly organic matter (litter and humus) • A horizon o organic carbon accumulation, some removal of clay • E horizon o zone of maximum removal (loss of OC, Fe, Mn, Al, clay…) • B horizon o forms below O, A, and E horizons o zone of maximum accumulation (clay, Fe, Al, CaC03, salts…) o most developed part of subsoil (structure, texture, color) o < 50% rock structure or thin bedding from water deposition Master Horizons • C horizon o little or no pedogenic alteration o unconsolidated parent material or soft bedrock o < 50% soil structure • R horizon o hard, continuous bedrock A vs. -
Port Silt Loam Oklahoma State Soil
PORT SILT LOAM Oklahoma State Soil SOIL SCIENCE SOCIETY OF AMERICA Introduction Many states have a designated state bird, flower, fish, tree, rock, etc. And, many states also have a state soil – one that has significance or is important to the state. The Port Silt Loam is the official state soil of Oklahoma. Let’s explore how the Port Silt Loam is important to Oklahoma. History Soils are often named after an early pioneer, town, county, community or stream in the vicinity where they are first found. The name “Port” comes from the small com- munity of Port located in Washita County, Oklahoma. The name “silt loam” is the texture of the topsoil. This texture consists mostly of silt size particles (.05 to .002 mm), and when the moist soil is rubbed between the thumb and forefinger, it is loamy to the feel, thus the term silt loam. In 1987, recognizing the importance of soil as a resource, the Governor and Oklahoma Legislature selected Port Silt Loam as the of- ficial State Soil of Oklahoma. What is Port Silt Loam Soil? Every soil can be separated into three separate size fractions called sand, silt, and clay, which makes up the soil texture. They are present in all soils in different propor- tions and say a lot about the character of the soil. Port Silt Loam has a silt loam tex- ture and is usually reddish in color, varying from dark brown to dark reddish brown. The color is derived from upland soil materials weathered from reddish sandstones, siltstones, and shales of the Permian Geologic Era. -
Determination of Geotechnical Properties of Clayey Soil From
DETERMINATION OF GEOTECHNICAL PROPERTIES OF CLAYEY SOIL FROM RESISTIVITY IMAGING (RI) by GOLAM KIBRIA Presented to the Faculty of the Graduate School of The University of Texas at Arlington in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE IN CIVIL ENGINEERING THE UNIVERSITY OF TEXAS AT ARLINGTON August 2011 Copyright © by Golam Kibria 2011 All Rights Reserved ACKNOWLEDGEMENTS I would like express my sincere gratitude to my supervising professor Dr. Sahadat Hos- sain for the accomplishment of this work. It was always motivating for me to work under his sin- cere guidance and advice. The completion of this work would not have been possible without his constant inspiration and feedback. I would also like to express my appreciation to Dr. Laureano R. Hoyos and Dr. Moham- mad Najafi for accepting to serve in my committee. I would also like to thank for their valuable time, suggestions and advice. I wish to acknowledge Dr. Harold Rowe of Earth and Environmental Science Department in the University of Texas at Arlington for giving me the opportunity to work in his laboratory. Special thanks goes to Jubair Hossain, Mohammad Sadik Khan, Tashfeena Taufiq, Huda Shihada, Shahed R Manzur, Sonia Samir,. Noor E Alam Siddique, Andrez Cruz,,Ferdous Intaj, Mostafijur Rahman and all of my friends for their cooperation and assistance throughout my Mas- ter’s study and accomplishment of this work. I wish to acknowledge the encouragement of my parents and sisters during my Master’s study. Without their constant inspiration, support and cooperation, it would not be possible to complete the work. -
A Study of Unstable Slopes in Permafrost Areas: Alaskan Case Studies Used As a Training Tool
A Study of Unstable Slopes in Permafrost Areas: Alaskan Case Studies Used as a Training Tool Item Type Report Authors Darrow, Margaret M.; Huang, Scott L.; Obermiller, Kyle Publisher Alaska University Transportation Center Download date 26/09/2021 04:55:55 Link to Item http://hdl.handle.net/11122/7546 A Study of Unstable Slopes in Permafrost Areas: Alaskan Case Studies Used as a Training Tool Final Report December 2011 Prepared by PI: Margaret M. Darrow, Ph.D. Co-PI: Scott L. Huang, Ph.D. Co-author: Kyle Obermiller Institute of Northern Engineering for Alaska University Transportation Center REPORT CONTENTS TABLE OF CONTENTS 1.0 INTRODUCTION ................................................................................................................ 1 2.0 REVIEW OF UNSTABLE SOIL SLOPES IN PERMAFROST AREAS ............................... 1 3.0 THE NELCHINA SLIDE ..................................................................................................... 2 4.0 THE RICH113 SLIDE ......................................................................................................... 5 5.0 THE CHITINA DUMP SLIDE .............................................................................................. 6 6.0 SUMMARY ......................................................................................................................... 9 7.0 REFERENCES ................................................................................................................. 10 i A STUDY OF UNSTABLE SLOPES IN PERMAFROST AREAS 1.0 INTRODUCTION -
Frequency and Magnitude of Selected Historical Landslide Events in The
Chapter 9 Frequency and Magnitude of Selected Historical Landslide Events in the Southern Appalachian Highlands of North Carolina and Virginia: Relationships to Rainfall, Geological and Ecohydrological Controls, and Effects Richard M. Wooten , Anne C. Witt , Chelcy F. Miniat , Tristram C. Hales , and Jennifer L. Aldred Abstract Landsliding is a recurring process in the southern Appalachian Highlands (SAH) region of the Central Hardwood Region. Debris fl ows, dominant among landslide processes in the SAH, are triggered when rainfall increases pore-water pressures in steep, soil-mantled slopes. Storms that trigger hundreds of debris fl ows occur about every 9 years and those that generate thousands occur about every 25 years. Rainfall from cyclonic storms triggered hundreds to thousands of debris R. M. Wooten (*) Geohazards and Engineering Geology , North Carolina Geological Survey , 2090 US Highway 70 , Swannanoa , NC 28778 , USA e-mail: [email protected] A. C. Witt Virginia Department of Mines, Minerals and Energy , Division of Geology and Mineral Resources , 900 Natural Resources Drive, Suite 500 , Charlottesville , VA 22903 , USA e-mail: [email protected] C. F. Miniat Coweeta Hydrologic Lab , Center for Forest Watershed Research, USDA Forest Service, Southern Research Station , 3160 Coweeta Lab Road , Otto , NC 28763 , USA e-mail: [email protected] T. C. Hales Hillslope Geomorphology , School of Earth and Ocean Sciences, Cardiff University , Main Building, Park Place , Cardiff CF10 3AT , UK e-mail: [email protected] J. L. Aldred Department of Geography and Earth Sciences , University of North Carolina at Charlotte , 9201 University City Blvd. , Charlotte , NC 28223 , USA e-mail: [email protected] © Springer International Publishing Switzerland 2016 203 C.H. -
Choosing a Soil Amendment Fact Sheet No
Choosing a Soil Amendment Fact Sheet No. 7.235 Gardening Series|Basics by J.G. Davis and D. Whiting* A soil amendment is any material added not be used as a soil amendment. Don’t add Quick Facts to a soil to improve its physical properties, sand to clay soil — this creates a soil structure such as water retention, permeability, water similar to concrete. • On clayey soils, soil infiltration, drainage, aeration and structure. Organic amendments increase soil amendments improve the The goal is to provide a better environment organic matter content and offer many soil aggregation, increase for roots. benefits. Over time, organic matter improves porosity and permeability, and To do its work, an amendment must be soil aeration, water infiltration, and both improve aeration, drainage, thoroughly mixed into the soil. If it is merely water- and nutrient-holding capacity. Many and rooting depth. buried, its effectiveness is reduced, and it will organic amendments contain plant nutrients interfere with water and air movement and and act as organic fertilizers. Organic matter • On sandy soils, soil root growth. also is an important energy source for amendments increase the Amending a soil is not the same thing bacteria, fungi and earthworms that live in water and nutrient holding as mulching, although many mulches also the soil. capacity. are used as amendments. A mulch is left on the soil surface. Its purpose is to reduce Application Rates • A variety of products are available bagged or bulk for evaporation and runoff, inhibit weed growth, Ideally, the landscape and garden soils and create an attractive appearance. -
General Soil Information and Specs
Extension Education Center 423 Griffing Avenue, Suite 100 Riverhead, New York 11901-3071 t. 631.727.7850 f. 631.727.7130 General Soil Information and Specs Is there an easy way I can tell what kind of soil I am working with? Yes. Use the following ribbon test. 1. Place 2 teaspoons of the soil in your palm and drip water onto it, kneading until it forms a ball. 2. Does the soil remain in a ball when squeezed? If not, you have mostly sand. 3. If the ball forms, squeeze it between your thumb and forefinger into a ribbon of sorts. Loam: Weak ribbon less than 1 inch before breaking. If the ribbon holds together and appears to be “ruffled” or has cracks it, you probably have a silty loam. Clay Loam: Medium ribbon 1 to 2 inches before breaking. Clay: Strong Ribbon 2 inches or longer before breaking, which could explain some of the drainage problems you have been having. Is there a formal definition for sand? Many of the sand materials I have looked at seem completely different from each other. Sand doesn’t have to be 100% sand, and in fact it is any soil material with 85 or more percent of sand. Taken backwards, a sand is any soil material where the percentage of silt PLUS 1.5 times the percentage of clay does not exceed 15. 85 plus 15 equals 100. The official abbreviation is Sa. My specs call for coarse sand. What is that? How does it differ from fine sand? Coarse sand is defined as 25% or more very coarse and coarse sand and less than 50% of any other single grade of sand. -
Geotechnical Manual 2013 (PDF)
2013 Geotechnical Engineering Manual Geotechnical Engineering Section Minnesota Department of Transportation 12/11/13 MnDOT Geotechnical Manual ii 2013 GEOTECHNICAL ENGINEERING MANUAL ..................................................................................................... I GEOTECHNICAL ENGINEERING SECTION ............................................................................................................... I MINNESOTA DEPARTMENT OF TRANSPORTATION ............................................................................................... I 1 PURPOSE & OVERVIEW OF MANUAL ........................................................................................................ 8 1.1 PURPOSE ............................................................................................................................................................ 8 1.2 GEOTECHNICAL ENGINEERING ................................................................................................................................. 8 1.3 OVERVIEW OF THE GEOTECHNICAL SECTION .............................................................................................................. 8 1.4 MANUAL DESCRIPTION AND DEVELOPMENT .............................................................................................................. 9 2 GEOTECHNICAL PLANNING ....................................................................................................................... 11 2.1 PURPOSE, SCOPE, RESPONSIBILITY ........................................................................................................................ -
Silt Fence (1056)
Silt Fence (1056) Wisconsin Department of Natural Resources Technical Standard I. Definition IV. Federal, State, and Local Laws Silt fence is a temporary sediment barrier of Users of this standard shall be aware of entrenched permeable geotextile fabric designed applicable federal, state, and local laws, rules, to intercept and slow the flow of sediment-laden regulations, or permit requirements governing sheet flow runoff from small areas of disturbed the use and placement of silt fence. This soil. standard does not contain the text of federal, state, or local laws. II. Purpose V. Criteria The purpose of this practice is to reduce slope length of the disturbed area and to intercept and This section establishes the minimum standards retain transported sediment from disturbed areas. for design, installation and performance requirements. III. Conditions Where Practice Applies A. Placement A. This standard applies to the following applications: 1. When installed as a stand-alone practice on a slope, silt fence shall be placed on 1. Erosion occurs in the form of sheet and the contour. The parallel spacing shall rill erosion1. There is no concentration not exceed the maximum slope lengths of water flowing to the barrier (channel for the appropriate slope as specified in erosion). Table 1. 2. Where adjacent areas need protection Table 1. from sediment-laden runoff. Slope Fence Spacing 3. Where effectiveness is required for one < 2% 100 feet year or less. 2 to 5% 75 feet 5 to 10% 50 feet 4. Where conditions allow for silt fence to 10 to 33% 25 feet be properly entrenched and staked as > 33% 20 feet outlined in the Criteria Section V. -
Types of Landslides.Indd
Landslide Types and Processes andslides in the United States occur in all 50 States. The primary regions of landslide occurrence and potential are the coastal and mountainous areas of California, Oregon, Land Washington, the States comprising the intermountain west, and the mountainous and hilly regions of the Eastern United States. Alaska and Hawaii also experience all types of landslides. Landslides in the United States cause approximately $3.5 billion (year 2001 dollars) in dam- age, and kill between 25 and 50 people annually. Casualties in the United States are primar- ily caused by rockfalls, rock slides, and debris flows. Worldwide, landslides occur and cause thousands of casualties and billions in monetary losses annually. The information in this publication provides an introductory primer on understanding basic scientific facts about landslides—the different types of landslides, how they are initiated, and some basic information about how they can begin to be managed as a hazard. TYPES OF LANDSLIDES porate additional variables, such as the rate of movement and the water, air, or ice content of The term “landslide” describes a wide variety the landslide material. of processes that result in the downward and outward movement of slope-forming materials Although landslides are primarily associ- including rock, soil, artificial fill, or a com- ated with mountainous regions, they can bination of these. The materials may move also occur in areas of generally low relief. In by falling, toppling, sliding, spreading, or low-relief areas, landslides occur as cut-and- La Conchita, coastal area of southern Califor- flowing. Figure 1 shows a graphic illustration fill failures (roadway and building excava- nia. -
Soil Texture Chart Chart the Soil Texture Chart Gives Names Associated with Various Combinations of Sand, Silt and Clay and Is Used to Classify the Texture of a Soil
Name: _________________________________ Soil Texture Directions: Read, highlight, and answer the schoology questions. Until now, we have spent our time defining soil. We know that soil comes from broken down rocks and minerals that have been weathered both mechanically and chemically. We also know that soil contains a variety of parts consisting of sand, soil, clay, and humus. But what is the best soil? I’m sure you are saying loam is the best. You are right, but what exactly is loam? To understand loam, we need to understand how three parts of soil come together. If I were to ask you to draw soil, it would probably look like the image to the right. Most would just draw a pile of dirt. As we are learning though, soil is much more complex than that. Sand, Silt and Clay One of the key ways that we characterize rocks is by texture. Remember that texture refers to how something feels. It can feel grainy, rough, or smooth. Larger particles feel rough while smaller particles feel smooth. For soil, we also use texture to help characterize the type. The texture of soil, just like rocks, refers to the size of the particles that make up the soil. The terms sand, silt, and clay refer to different sizes of the soil particles. Sand, being the larger size of particles, feels gritty. Silt, being moderate in size, has a smooth or floury texture. Clay, being the smaller size of particles, feels sticky. Look at the figure to the right. The size of the circle is relative to each size particle. -
Silt Fences: an Economical Technique for Measuring Hillslope Soil Erosion
United States Department of Agriculture Silt Fences: An Economical Technique Forest Service for Measuring Hillslope Soil Erosion Rocky Mountain Research Station General Technical Peter R. Robichaud Report RMRS-GTR-94 Robert E. Brown August 2002 Robichaud, Peter R.; Brown, Robert E. 2002. Silt fences: an economical technique for measuring hillslope soil erosion. Gen. Tech. Rep. RMRS-GTR-94. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 24 p. Abstract—Measuring hillslope erosion has historically been a costly, time-consuming practice. An easy to install low-cost technique using silt fences (geotextile fabric) and tipping bucket rain gauges to measure onsite hillslope erosion was developed and tested. Equipment requirements, installation procedures, statis- tical design, and analysis methods for measuring hillslope erosion are discussed. The use of silt fences is versatile; various plot sizes can be used to measure hillslope erosion in different settings and to determine effectiveness of various treatments or practices. Silt fences are installed by making a sediment trap facing upslope such that runoff cannot go around the ends of the silt fence. The silt fence is folded to form a pocket for the sediment to settle on and reduce the possibility of sediment undermining the silt fence. Cleaning out and weighing the accumulated sediment in the field can be accomplished with a portable hanging or plat- form scale at various time intervals depending on the necessary degree of detail in the measurement of erosion (that is, after every storm, quarterly, or seasonally). Silt fences combined with a tipping bucket rain gauge provide an easy, low-cost method to quantify precipitation/hillslope erosion relationships.