Lab Report 5 Soil Analysis

Lab Report 5 Soil analysis Abstract: This report is based on the analysis of two soil types in East Sussex with the intention to evaluate soil fertility and erodibility. Objectives are to describe and identify the horizons of two soils, using scaled drawing. To determine physical and chemical properties of samples from both soils. The methods used are found in the module handbook. The results show a clear distinction between soil types 1 and 2. Soil 1 is a freely draining slightly acidic soil (sandstone), soil 2 is Shallow lime-rich soil (Chalk) Introduction “Soil testing is defined as “rapid chemical analyses to assess the plant available nutrient status, salinity, and elemental toxicity of a soil “(Peek and Soltanpour, 1990) [cited by (Huang, et al., 2012)]. This report is based on the analysis of properties of two soil types i n East Sussex to evaluate soil fertility and erodibility. Field scientists are interested in soil analysis for land use management, crop production, protection of human health and, or the environment. ( Huang, et al., 2012). The main objectives are to describe and identify the horizons of two soils, using scaled drawing of two soil profiles. To determine some physical and chemical properties of samples from both soils. Methods See handbook for methods. Results Figure 1 illustrates a scaled drawing of two soil profiles in East Sussex. The profiles have been divided into horizons/layers and labelled according to the soil horizon designatio n for British soils. The two profiles have also been scaled to size. Profile 1 is approximately 2m and profile 2 is approximately 1.2m.The capital letters in the first horizon represents the surface accumulation of organic matter Soil profile 1 L= little decompose litter. Soil 2 H= a thoroughly decomposed organic layer, often with some mineral particles. Both profiles in horizon 1 consist of a mineral topsoil which is unploughed (Ah). Profile 1 Horizon 2 demonstrates a subsoil horizon depleted of clay (Eb). Profile 2 horizon 2 however jumps to a bedrock too hard to dig with a spade when moist (R). Horizon 3 and 4 of Soil profile 1 is an altered subsoil horizon (Ba) and at the very bottom is bedrock too hard to dig with a spade when moist (R). Table 1 provides the data for the soil properties taken in the laboratory for soils 1 and 2. The table shows a clear distinction between the soil types. Soil Properties Munsell colour Particle size Organic content (%) Organic carbon (%) Carbonate content (%) Moisture content (%) Water-stable aggregates (%) Potassium (ppm) Phosphate (%) (ml) Nitrate (%) (ml) pH Suggested soil type Suggested substrate type Soil #1 Dark Brown 7.5YR/3V/3C Silty Loam 0.002-0.019mm 2.39 1.78 1.39 21.90 3.12 295ppm 4mg/l 22.7 5.5 Freely draining slightly acidic soil (sandy) Sandstone Soil #2 Greyish Brown 10YR/5V/2C Clay Loams <0.002mm 28.04 16.26 34.12 20.16 2.7 150ppm 25mg/l 21.5 6.4 Shallow lime-rich soil (Loamy) Chalk Discussion/interpretation 1. Soil horizon identification and description. “A soil profile is the vertical section that includes all layers that have been chemically altered ” (Velde & Meunier , 2008 ) Figure 1, Profile 1, and Horizon 1 (L) (Ah) layer is formed from organic material on the surface layer and decomposing debris. This horizon is thin suggesting little decomposition (schaetzl & Thompson, 2015). Horizon 2(Ah). Is darker in colour proposing further decomposition of organic material indicating carbon rich material. Horizon 3 (Ba) is light brown perhaps from a change in chemical composition from oxidised iron. The final Horizon 4 (R) solidity suggests long timescale and subjection to heat and pressure. Profile 2 has only 2 horizons. Horizon 1 (H), (Ah). Appears softer darker than profile 1 indicating it is more carbon rich. It also appears s moist. Horizon 2 (R) however is very solid. The jump between the two horizons suggests there are horizons missing. Table 1 2. Soil Colour. Hue is “the attribute of a colour by virtue of which it is discernible as red, green, etc., and which is dependent on its dominant wavelength and independent of intensity or lightnes s” (Oxford Dictionary, 2016). Soil 1 is Yellow, Red. The Value is 7.5 the relative amount of black versus white. And the Chroma indicating the saturation of the Colour is 3. The result is a dark brown soil. The soil colour suggests the soil has been oxidised by iron it also suggests presence of “relatively large crystals of goethite giving the ubiquitous yellow pigment of aerobic soils” (United Stated Department of Agriculture, 2000). Soil 2 Lack of colour suggests an anaerobic environment whereby perhaps there is an abundance of water, as a result iron is reduced to colourless and turns into water soluble ferrous iron the loss of pigment turning the soil grey. 3. Qualitative Particle size. The particle size of soils tends to be strongly influenced the underlying bedrock or superficial deposits in which a soil is developed. In the case of Soil 1, silt it may have perhaps been deposited by wind however the underlying bedrock may have been eroded to form silt. Soil 2 resembles clay, clay minerals are hydrophilic which suggests soil 2 is found in an area which is abundant in water. 4. Organic content, organic carbon and carbonate content and PH organic carbon provides a food source for micro-organisms which help improve soil stability by micro-organisms binding soil particles together into aggregates, the results demonstrate soil 1 suggests the soil is not stable. Carbonate content relates to soil PH due to its neutralising potential for example soil 1 has a PH of 5.5 which is acidic therefor the carbonate has a low neutralising potential (1.39%). Soil 2 results suggests good stability, and its PH of 6.4 suggests the carbonate has a good neutralising potential which is close to 7 (neutral). 5. Soil Moisture content and water-stable aggregates Soil 1 has 3.12% of moisture and Soil 2 has 2.7. This suggests soil 1 is more resistant to soil disintegration by rainfall and saturation compared to soil 2. It also indicates that soil 1 is more likely to disintegrate due to erosion than soil 2. The organic content also suggests that soil 2 (28.04%) is more stable in comparison to soil 1 (2.39%). 6. SOIL CHEMICAL ANALYSIS / FERTILITY TESTS Soil 1 results suggests it is good at regulating CO2 uptake, regulating water cycle, and reproduction. However the low phosphate level suggests this soil is not good for blooming or root growth despite this the Nitrate is sufficient for photosynthesis. Soil 2 outcomes suggest it is a good soil for root growth and blooming and has a sufficient amount of nutrients for photosynthesis, carbon dioxide uptake and water cycle regulation. Conclusion There is a clear difference between the soil types soil 1 is susceptible to erosion and has a low fertility. In contrast soil 2 is very fertile and not as susceptible to erosion. Soil 1 is freely draining slightly acidic soil (Sandstone) Soil 2 is Shallow lime-rich soil (Chalk). References Hua ng , P. M., Li , Y. & Sumner , M. E., 2012. Handbook Of Soil Sciences: Resource Management and Environmental Impacts. 2nd ed. s .l.:CRC Press. Oxford Di ctionary, 2016. Hue. [Onli ne] Ava ilable at: http://www.oxforddictionaries.com/definition/english/hue [Acces sed 14 Ja nuary 2016]. schaetzl, R. J. & Thompson, M. L., 2015. Soils Genesis and Geomorphology. 2nd ed. United States Of America : Ca mbridge University Press. Soil Survey Sta ff , 1999. Soil Taxonomy: A Basic System Of Soil Classification For Making and Interpretating Soil Surveys. 2nd ed. Washington DC: U.S Department of Agriculture Handbook 436. Natural Resources Conserva tion Service. United Stated Department of Agriculture, 2000. The Colour Of Soil. [Onl ine] Ava ilable at: http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/edu/?cid=nrcs142p2_054286 [Acces sed 14 Ja nuary 2016]. Velde , B. & Meunier , A., 2008 . The Origins of Clay minerals and weathered Rocks. Berlin : Springer .