Laboratory Methods for Soil Health Analysis, Volume 2. Группа авторов. Читать онлайн. Newlib. NEWLIB.NET

Автор: Группа авторов
Издательство: John Wiley & Sons Limited
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Жанр произведения: Биология
Год издания: 0
isbn: 9780891189862
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specified by the individual researcher as needed for the goals of the research and as constrained by the research budget.

Indicator Method Reference
Soil pH 1:2 soil:water, standard pH electrode system Thomas, 1996
Soil Electrical Conductivity (EC) 1:2 soil:water, standard electrical conductivity meter system Rhoades, 1996
Cation Exchange Capacity (CEC) Sum of cations: Soil pH ≥ 7.2: use ammonium acetate extractant; Soil pH < 7.2: use Mehlich 3 extractant Knudsen et al., 1982 Sikora and Moore, 2014
% Base Saturation (BS) Calculation: For soil pH ≥ 7.2: use ammonium acetate extractant; for soil pH < 7.2: use Mehlich 3 extractant Knudsen et al., 1982 Sikora and Moore, 2014
Extractable Phosphorus Soil pH ≥ 7.2: use sodium bicarbonate extractant; Soil pH < 7.2: use Mehlich 3 extractant Olsen and Sommers, 1982 Sikora and Moore, 2014
Extractable Potassium, Calcium, Magnesium, Sodium pH ≥ 7.2: use ammonium acetate extractant; Soil pH < 7.2: use Mehlich 3 extractant Knudsen et al., 1982 Sikora and Moore, 2014
Extractable Iron, Zinc, Manganese, Copper DTPA extractant derivatives Lindsay and Norvell, 1978
Total Nitrogen Dry combustion Nelson and Sommers, 1996
Soil Organic Carbon (SOC) Dry combustion; corrected for inorganic C, if present, using pressure calcimeter Nelson and Sommers, 1996 Sherrod et al., 2002
Soil Texture Pipette method with a minimum of 3 size classes. Weight/volume measurements Gee and Bauder, 1986
Aggregate Stability Wet sieve procedure. Weight measurement Water slaking image recognition Kemper and Roseneau, 1986 Mikha and Rice, 2004 Fajardo et al., 2016
Available Water Holding Capacity Ceramic plate method measured at –33 kPa (–10 kPa for sandy soils) and –1500 kPa Klute, 1986
Bulk Density (BD) Core method: diameter to be determined, (most likely 2‐inch or 5.08 cm) Blake and Hartge, 1986
Saturated Hydraulic Conductivity Two‐ponding head method in field with Saturo Reynolds and Elrick, 1990
Crop Yield Obtained from historical and current plot yield data provided by site manager
Short‐Term Carbon Mineralization 4‐d incubation followed by CO2–C evolution and capture at 50% water‐filled pore space. Zibilske, 1994
Potentially Mineralizable Nitrogen Short‐term anaerobic incubation with ammonium and nitrate measured colorimetrically pre‐ and post‐incubation Bundy and Meisinger, 1994

      Service labs must maintain consistent quality of data if they are to remain in business. A farmer must have confidence that analyses conducted in different years or on different parts of the farm reflect real properties of the soil, and if changes in a measurement are occurring, that these really do reflect changes in soil on the farm. Service labs may strive to achieve this reliability through associations with organizations that provide independent testing and verification of laboratory results.

Indicator Method Reference
Sodium Adsorption Ratio (SAR) Saturated paste extract followed by atomic absorption or inductively coupled plasma spectroscopy Miller et al., 2013
Soil Stability Index Combination of wet and dry sieving at multiple sieve sizes Franzluebbers et al., 2000
Active Carbon Permanganate oxidizable carbon (POXC). Digestion followed by colorimetric measurement Weil et al., 2003
Soil Protein Index Autoclaved citrate extractable Schindelbeck

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