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The soil ecosystem
Published in Stephen R. Gliessman, V. Ernesto Méndez, Victor M. Izzo, Eric W. Engles, Andrew Gerlicz, Agroecology, 2023
Stephen R. Gliessman, V. Ernesto Méndez, Victor M. Izzo, Eric W. Engles, Andrew Gerlicz
Soil color plays its most important role in the identification of soil types, but at the same time it can tell us much about the history of a soil’s development and management. Dark-colored soils, for example, are generally an indication of high organic matter content, especially in temperate regions. Red and yellow soils generally indicate high levels of iron oxides, formed under conditions of good aeration and drainage; gray or yellow-brown colors can be indicators of poor drainage. Hence, a soil’s color can be an indicator of certain kinds of soil conditions that a farmer might want to look for or avoid, depending on the cropping systems that might be used. In addition, soil color influences the interaction of the soil with sunlight. A lighter-colored soil better reflects the sun’s rays and keeps the soil cooler; conversely, a darker soil absorbs more heat from the sun.
Weathering and Soils
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Soil color is one of the easiest ways to tell soils apart and is also the easiest way to see soil horizons (Fig. 11.44). Although color is not a good indicator of all soil attributes, it does provide information about soil composition and moisture content, and about the nature of the parent material. Usually, soil color reflects the presence of different iron oxides, carbonates or other salts, or eluviated humus. Figure 11.44 shows some examples of different colored soils. Highly leached soils, like the North Carolina soil, may have a very red color due to concentration of iron oxides, especially hematite, and absence of other mineral matter. The South Dakota soil is dark colored due to high organic content. The Texas soil contains nodules of caliche (white calcium carbonate). The Rhode Island soil is yellowish due to high goethite (an iron hydroxide) content.
Spectral Sensing from Ground to Space in Soil Science: State of the Art, Applications, Potential, and Perspectives
Published in Prasad S. Thenkabail, Land Resources Monitoring, Modeling, and Mapping with Remote Sensing, 2015
José A. M. Demattê, Cristine L.S. Morgan, Sabine Chabrillat, Rodnei Rizzo, Marston H.D. Franceschini, Fabrício da S. Terra, Gustavo M. Vasques, Johanna Wetterlind
Why do we need to use geotechnologies for soil mapping? During the ¤eldwork, the pedologist starts to create a mental picture of the soil boundaries envisioning a soil class map. In this task, several tools can be used, including RS. Aerial photographs have been extensively used in the past (and still today). Vink (1964) proved that the use of aerial photographs added e¶ciency to soil mapping, requiring less ¤eldwork compared to mapping procedures done without this product. Later on, Campos and Demattê (2004) highlighted the importance of using a colorimeter to quantify soil color in substitution to the visual comparison with Munsell soil color charts. ey compared data from ¤ve pedologists that performed soil color for the same sample using the Munsell color chart approach. ey observed a 17.5% and 8.7% agreement among pedologists for dried and moist samples, respectively. All pedologists superestimated the hue, with consequences for soil classi¤cation. Given that ¤eld light conditions are highly variable, and the eye sensitivity changes by person and with age, among other factors, we argue that automatic systems should be used for color determination. Bazaglia
Evaluating the status of phytochemicals within Catharanthus roseus due to higher metal stress
Published in International Journal of Phytoremediation, 2021
V. Soumya, A. Sowjanya, P. Kiranmayi
Soil color is produced by the presence of minerals and organic matter content. Yellow or red soil indicates the presence of ferric iron oxides. Dark brown or black color in soil indicates that the soil has a high organic matter content. Also, soils having greater moisture content appear darker than dry soil. The color of the soil samples was assessed based on Munsell color system (Cochrane 2014). The system depends on three components viz. hue, value and chroma. Hue is the quality by which we distinguish one color from another like red (R), yellow(Y), green(G), yellow-red (YR) etc. Value is the lightness and darkness of the color ranging from 0 (black) to 10 (white). Chroma is the saturation of the color where brighter colors have higher numbers. The color notation is thereby indicated as “Hue Value/Chroma.”
Inactivation of Fusarium oxysporum Conidia in Soil with Gaseous Ozone – Preliminary Studies
Published in Ozone: Science & Engineering, 2020
Jhon Harley Muñoz Romero, Cindy Alejandra Sepúlveda Cadavid, Natalie Cortés, Julián Esteban López Correa, Juan David Correa Estrada
The collected soil was exposed to a preliminary preparation process for physicochemical testing (NTC 11464), except structure and bulk density samples. All samples were air-dried; afterward, gravel, roots, and any other material different from soil was removed. Lastly, the soil was triturated until grain size smaller than 2 mm. Bulk density was determined by the cylinder method (Jaramillo 2014). To determine aggregates distribution, 200 g of dry soil was screened through sieves of 5–2–1–0.5–0.25 & 0.1 mm of diameter (NTC 1522). OM quantity in soil was determined through calcination method (Jaramillo 2014). To determine soil texture, Bouyoucos method was used (Bouyoucos 1962). The soil color was determined through the Munsell color chart (Jaramillo and Daniel 2002). A soil suspension of 1:2 and 1:5 soil:distilled water (weight/volume) was used to measure pH (pH Bench Meter ST3100; OHAUS Corporation USA) and electric conductivity (Conductivity Meter HI 8033; HANNAH Instruments), respectively (NTC 5264; NTC 5596). Finally, to determine water retention capacity (WRC), 10 g of soil was dried at 70°C for 24 h to be hydrated with distilled water until saturation (Tello and Vega 2015). Physicochemical parameters are shown in Table 1.
Mycological assisted phytoremediation enhancement of bioenergy crops Zea mays and Helianthus annuus in heavy metal contaminated lithospheric zone
Published in Soil and Sediment Contamination: An International Journal, 2019
Shazia Iram, Rabia Basri, Khuram Shahzad Ahmad, Shaan Bibi Jaffri
Selected soils were characterized for different physical (color, texture, pH, electrical conductivity) and chemical (HM extent) parameters. Munsell soil color chart was used for the determination of soil color. Soil texture was determined by the accurate calculation of the different fractions of gravel, sand, silt and clay obtained from digital electronic octagon sieve shaker after 60 min shaking. Soil pH was determined by using Crison MM 40 pH in 1:2 soil water suspensions. The soil electrical conductivity (EC) was verified by using Crison MM 40 EC meter in 1:2 soil water solution. Heavy metal analysis of soil sample before and after phytoremediation experiment was done by soil digestion. The analysis for different heavy metals i.e. Ni, Cu, Cd, Pd and Cr, atomic absorption spectrophotometer (AAS model 220 Spectra AA Varian) was used.