Lab 1 Soil Characterization Parent Material

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Following the retreat of the Wisconsin glaciers from this area a 980 foot deep. glacial lake Glacial Lake Ithaca was formed Lake Ithaca encompassed all of. the main Cornell campus and parts of Ithaca Newfield and Caroline von. Engeln 1961 von Engeln 1960 Sediments accumulated at the bottom of the. lake and beaches and deltas developed at its shoreline About 70000 years ago. the lake drained and the silt and clay sediments deposited at the bottom of. Glacial Lake Ithaca over glacial till and outwash were exposed The parent. material of soil developed from this lake deposited material is called lacustrine. Streams that fed the lake formed deltas consisting of coarser material that was. deposited as fast moving water slowed upon entering the glacial lake Coarse. material is also found along what were the beaches of Glacial Lake Ithaca Much. later after the lake had drained new streams formed cutting down through. existing sediments and bedrock As the streams flooded in spring they built. terraces of coarse sediments In general sediments deposited by moving water. are known as alluvium As the earth surface continued to rebound from the. glacial period these streams cut further down thus abandoning their old terraces. and forming new younger alluvial terraces, Each of these parent materials influences soil properties differently Glacial till. deposits are poorly sorted and heterogeneous mixtures of clay sand gravel and. boulders with varying texture and mineralogy Glacial outwash materials are. coarse textured and better sorted due to the influence of water and lacustrine. sediments are even more sorted and finer textured As you characterize soils. formed from these different parent materials look for variations in color texture. structure pH and in soil horizons, Figure 1 View from West Hill of Glacial Lake Ithaca. From Cornell Plantations When icebergs were floating over the Cornell. Plantations by O D von Engeln,Soil Properties Color Structure and Texture. Color is the most obvious of soil properties and it provides important clues about. organic matter drainage and other soil conditions A darker color can indicate. more organic matter is present compared to soil of a lighter color Often the. surface horizon called the epipedon has a darker color than the subsoil due to. higher organic matter content, How do we characterize soil color With the aid of the Munsell Soil Color Chart. we can distinguish a soil s color according to its hue chroma and value Soil. hues range from red to yellow red YR to yellow Y and sometimes green. yellow GY or even green G Hue is subdivided by prefixes from 0 to 10 and. all Munsell soil color books have pages 1 OR 2 5R 5YR 7 5YR 10YR 2 5Y. and 5Y Temperate region soils tend to have a 10YR hue whereas warmer. climates have both redder soils 10R and yellower 2 5Y 5Y soils Color value. for soil ranges from 0 for absolute black and 10 for absolute white gray has a. number 5 The chroma scale for soil ranges from 0 for neutral or gray colors to 8. for bright colors, To use the Munsell Color Book take a soil sample and locate the appropriate.
hue page The hue notation is listed on the upper right hand corner of the page. Next hold the soil near the color chips and locate the appropriate value left hand. side and chroma bottom of page The same soil when dry tends to have a. higher value and chroma than when wet This is why both wet and dry soil color. are often determined Also color determination is best done during the middle of. the day The sample may appear redder early or late in the day when the sun is. low in the sky, Another easily observable property of soil is soil structure There are six basic. types of soil structure platy prismatic blocky granular loose structureless and. compacted structureless Bare in mind these are idealized types structure in. the field will generally resemble one of these types but don t get frustrated if you. don t see these exact forms in the field The more profiles you observe the. easier determining structure becomes, Texture is the relative proportion of sand silt and clay particles that make up soil. Soils having a moderate amount of sand silt and clay are called loams There. are 12 soil texture classes sand S loamy sand LS sandy loam SL loam. L silt loam SiL silt Si sandy clay loam SCL clay loam CL silty clay loam. SiCL sandy clay SC silty clay SiC and clay C Staff 1993. In the field the texture by feel method is used to determine soil texture See Soil. Guide in Field Kit A small soil sample is gradually wetted and kneaded to. determine textural class Since this is a tactile evaluation experience is. essential Don t expect to get this on the first try Throughout the first four labs. there will be ample opportunities to perfect your methodology. Soil pH is a measure of how acid pH 7 or basic pH 7 the soil is A method. of measuring soil pH in the field is to place soil in a spot plate and add an. indicator dye until the soil is saturated The soil is mixed with the indicator dye. which changes color depending on the soil pH This color is then compared to a. reference color card to determine the pH,Soil Horizons O A E B C. Color structure and texture are used to distinguish soil horizons There are five. master soil horizons O A E B and C that can be found above regolith A. profile may have all or some of these horizons, The O horizon is the uppermost layer and is usually fond only in areas that have. some sort of permanent vegetation It is a layer of plant litter lying on the surface. of the mineral soil Considerable decomposition or organic matter takes place in. this horizon giving the O horizon its characteristic dark color. The A horizon if present lies beneath the O horizon and is darker than the. underlying horizons although not as dark as the O due to accumulation of. organic matter in the soil surface Leaching is most intense in the soil surface. and causes solutes to move down the profile to the underlying horizons. Some soils have an E horizon below the A horizon An E horizon does not. accumulate organic matter yet is subject to leaching resulting in a lighter color. than the A or B horizon, Underlying these horizons is the B horizon This layer accumulates materials.
from the overlying layers and like the E horizon is low in organic matter although. not as light in color The B horizon is often identified by its structure usually. blocky or prismatic, Finally there is the C horizon This layer of parent material is least affected by. the soil forming processes, Exercise A Three Field Characterization Methodologies. Familiarization of the field methods of hand texturing color identification and pH. Soil samples from TAs,Water bottle,Munsell Color books. Cornell pH test kits, 1 Determine texture by feel method for each of the samples and record. 2 Determine field color using Munsell Color Book, 3 Determine field pH using the Cornell pH Test Kit.
Exercise B Profile Description,measuring tape,water bottle. Munsell color chart,muffin tin, 1 Make a preliminary differentiation of the soil horizons based on color and. structure and record in Table 1, 2 Measure the depth from the surface to the top and bottom of each horizon. 3 Record presence or absence of roots in each horizon. 4 Take a sample of each horizon and place in muffin tin. 5 Moisten some soil from each horizon and determine the wet soil color of. each horizon using the Munsell color chart Record results. 6 Use the texture by feel method to determine the soil texture of each. horizon Record results,7 Determine soil pH according to instructions. 8 Based on your analysis of soil color structure and texture decide whether. to accept or revise your determination of soil horizons. 9 Make a sketch of the soil horizons to scale and indicate the variability in. depth that you see across the face of the profile, 10 Describe the landscape topography in which the soil pit is found.
11 Determine the parent material of this soil see exercise C. Exercise C Maps this exercise will help you determine nature and sources of. parent materials, Materials Soil survey of Cornell University property and adjacent areas. 1 Check the,location of the soil,pit on the Cornell Bradfield Hall. University Property,map Figure 2 pg,2 Determine the. parent material from,Figure 1 Parent,materials of soils of. the area pg 5 and,compare that to,your field,assessment of.
parent material for,3 Determine which,of the 6 soil maps. A1 A2 B1 B2,C1 C2 you need to,refer to in order to. determine the soil,pit location Find,this map locate the. soil pit and,determine the map,symbol for that Approx. location Then location,check the Map of Soil Pit,legend pg 24 25.
to determine the,soil series name for,that symbol,4 Once you have. determined the soil name this is the Soil Series read the descriptions of the. corresponding soil series and soil phases pg 8 22 and compare these to your. descriptions,Assignment,Answer the following questions. 1 What is the name of the Soil Series, 2 A sketch of the soil with horizons identified and drawn to scale Include. this on a separate page and it should be large enough to identify horizon. descriptions, 3 A profile description Table 1 including depth of horizons color texture. and presence of roots,Table 1 Profile Description Site 1.
Horizon Texture Wet color pH Roots, 4 A description of the nature source and distribution of the soil parent. material s Report on what you found on site we discussed as well as. described in the CU Soil Survey You will be graded on your. completeness not the length your description need not be longer than. 100 to 200 words,Appendix A,ARKPORT SERIES, The Arkport series consist of very deep well drained soils formed in glacio fluvial deposits. having a high content of fine and very fine sand These soils have thin horizontal bands of. loamy material in the subsoil Saturated hydraulic conductivity is high throughout the mineral. soil Slope ranges from 0 to 60 percent The mean annual temperature is 48 degrees F and. the mean precipitation is about 38 inches, TAXONOMIC CLASS Coarse loamy mixed active mesic Lamellic Hapludalfs. TYPICAL PEDON Arkport very fine sandy loam on a 5 percent slope in a cultivated field. Colors are for moist soil unless otherwise noted, Ap 0 to 9 inches brown 7 5YR 4 2 very fine sandy loam weak fine granular structure very. friable few medium and common fine roots 1 percent very fine pebbles moderately acid. abrupt smooth boundary 7 to 12 inches thick, BE1 9 to 15 inches brown 7 5YR 5 4 very fine sandy loam weak fine granular structure.
friable common medium roots many fine pores moderately acid gradual wavy boundary. BE2 15 to 28 inches brown 7 5YR 5 4 loamy very fine sand in intricate pattern with brown. 7 5YR 5 2 clean very fine sand and few reddish brown 5YR 4 3 very fine sandy loam. lamellae 1 16 inch thick and 3 to 6 inches long massive very friable common fine and few. medium roots strongly acid abrupt wavy boundary Combined thickness of the BE horizons is. 0 to 23 inches thick, E and Bt1 28 to 45 inches light reddish brown 5YR 6 3 very fine sand E material massive. very friable reddish brown 5YR 5 4 very fine sandy loam Bt material as lamellae 1 16 to 4. inches thick that total 6 inches in thickness massive firm few medium roots strongly acid. abrupt wavy boundary, E and Bt2 45 to 58 inches light reddish brown 5YR 6 3 loamy fine sand intricately. patterned with reddish brown 5YR 4 4 wavy branching crudely horizontal lamellae 1 16 to. 1 2 inch thick that total 1 1 2 inches in thickness massive very friable lamellae are firm and. slightly plastic few roots strongly acid abrupt wavy boundary. E and Bt3 58 to 92 inches pinkish gray 5YR 6 2 loamy fine sand patterned with dark. reddish brown 5YR 3 4 fine sandy loam thin wavy horizontal branching lamellae that total 1. inch in thickness and by reddish brown 5YR 4 4 very fine sandy loam 1 2 inch thick lamellae. that total 4 inches in thickness massive very friable and friable few roots in upper part. moderately acid clear wavy boundary Combined thickness of the E and Bt horizons is 15 to. C 92 to 106 inches pinkish gray 5YR 6 2 fine sand single grain loose slightly acid. RANGE IN CHARACTERISTICS Solum thickness ranges from 40 to 100 inches Depth to. bedrock is greater than 60 inches Depth to carbonates ranges from 36 to more than 120 inches. Depth to the uppermost lamellae ranges from 9 to 30 inches Very fine sand plus silt ranges from. 30 to 80 percent and fine sand and coarser is greater than 15 percent throughout the soil Rock. fragments are usually absent but can range up to 10 percent. The Ap horizon has hue of 10YR through 7 5YR value of 3 through 5 and chroma of 2 or 3. Texture is loamy fine sand fine sand loamy very fine sand very fine sandy loam fine sandy loam. sandy loam or silt loam It has weak or moderate fine to coarse granular structure and is very. friable or friable Reaction ranges from very strongly acid through neutral Wooded or uncultivated. areas have an A horizon 1 to 4 inches thick with hue of 10YR or 7 5YR value of 2 or 3 and. chroma of 1 or 2, The BE horizon has hue of 10YR through 5YR value of 4 through 6 and chroma of 3 through 8. Texture is loamy fine sand very fine sand loamy very fine sand fine sandy loam or very fine. 2 Measure the depth from the surface to the top and bottom of each horizon 3 Record presence or absence of roots in each horizon 4 Take a sample of each horizon and place in muffin tin 5 Moisten some soil from each horizon and determine the wet soil color of each horizon using the Munsell color chart Record results 6 Use the texture

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