The ability to inventory soil C on landscapes is limited by the rapidly measure C. Diffuse reflectance spectroscopic analysis in near‐infrared (NIR, 400–2500 nm) and mid‐infrared (MIR, 2500–25000 regions provides means for measurement of To assess utility spectroscopy analysis, we compared obtain information from these spectral quantify total, organic, inorganic samples representing 14 series collected over a large region west central United States. soils temperature regimes ranged thermic...

We performed mid‐infrared (MidIR) spectral interpretation of fractionated fresh and incubated soils to determine changes in soil organic matter (SOM) chemistry during incubation. Soils from four sites three depths were processed obtain the light fraction (LF), particulate (POM), silt‐sized (silt), clay‐sized (clay) fractions. Our results show that LF clay fractions have distinct features regardless site. The is characterized by absorbance at 3400 cm −1 , as well between 1750 1350...

The objective of this work was to investigate the usefulness near infrared (NIR) reflectance spectroscopy in determining: (i) various constituents (total N, total C, active biomass and mineralisable pH), (ii) parameters (soil source, depth from which sample obtained, type tillage used) (iii) rate application NH 4 NO 3 fertiliser) low organic matter soils. A NIRSystems model 6250 spectrometer used scan soil samples ( n = 179) obtained experimental plots at two locations with three replicate...

Soil samples were analyzed conventionally and by mid-infrared diffuse reflectance spectroscopy for total C, N, pH, measures of biological activity. Ground, non KBr diluted, (n = 180) from experimental plots (two locations, three replicate plots, under plow no-till practices, rates N fertilizer, five depths) scanned 4000 to 400 cm-1 (4-cm-1 resolution, 64 co-added scans) on a DigiLab FTS-60 Fourier transform spectrometer using custom-made linear sample transport (50 2 mm area scanned)....

ABSTRACT Rapid and nondestructive methods such as diffuse reflectance infrared spectroscopy provide potentially useful alternatives to time‐consuming chemical of soil metal analysis. To assess the utility near‐infrared (NIRS) mid‐infrared (DRIFTS) for determination, 70 samples from mining region Tarnowskie Gory (Upper Silesia, Poland) were analyzed by both spectroscopic methods. Soils represented a wide range pH (4.0–8.0), total carbon (5.1–73.2 g kg −1 ), textural classes (from sand silty...

Abstract Current estimates of plant availability manure N are highly variable. A study was conducted to examine C and mineralization characteristics components from feeds (immature mature alfalfa orchardgrass, soybean meal, roasted meal), forage cell walls (acid detergent fiber [ADF] neutral [NDFI), simple compounds (urea, amino acids peptides), nondietary metabolic (ruminal bacteria colonic cells). Nitrogen were determined by aerobic incubation sample‐amended soil. Changes in NH + 4 NO − 3...

The ability to inventory soil C on landscapes is limited by the rapidly measure C. Diffuse reflectance spectroscopic analysis in near-infrared (NIR, 400–2500 nm) and mid-infrared (MIR, 2500–25000 regions provides means for measurement of To assess utility spectroscopy analysis, we compared obtain information from these spectral quantify total, organic, inorganic samples representing 14 series collected over a large region west central United States. soils temperature regimes ranged thermic...

Data-intensive technologies such as precision agriculture require new approaches for acquisition of soil data on landscapes. We compared the ability near infrared (NIR; 400-2500 nm) and mid (MIR; 2,500-25,000 spectroscopy field-scale fertility parameters. Samples were obtained in a grid pattern (25 m spacing) from surface (0-10 cm) sub-surface (10-30 samples collected at 272 locations. analyzed organic C total N, texture (clay, silt, sand), pH, Mehlich I extractable Ca, K, Mg, P. found that...

Soil hyperspectral reflectance imagery was obtained for six tilled (soil) agricultural fields using an airborne imaging spectrometer (400–2450 nm,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>∼</mml:mo></mml:math>10 nm resolution, 2.5 m spatial resolution). Surface soil samples (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>315</mml:mn></mml:mrow></mml:math>) were analyzed carbon content, particle size...

Denitrification N losses during manure net mineralizable assays may lead to miscalculation of the manure's N‐supplying capacity. In this study we measured denitrification, properties, gas fluxes, nutrient pools, and laboratory incubation manured soil. Different dairy manures ( n = 107) were added soil at a rate 0.1 mg g −1 Manured control soils incubated sampled weekly for mineral N, CO 2 flux, O flux. The denitrification enzyme activity (DEA) was end experiment. Weekly production increased...

Abstract The objective of this study was to compare mid‐infrared (MIR) an near‐infrared (NIR) spectroscopy (MIRS and NIRS, respectively) not only measure soil carbon content, but also key organic C (SOC) fractions the δ13C in a highly diverse set soils while assessing feasibility establishing regional diffuse reflectance calibrations for these fractions. Two hundred thirty‐seven samples were collected from 14 sites 10 western states (CO, IA, MN, MO, MT, ND, NE, NM, OK, TX). subsets examined...

The lack of predictability in litter‐mix studies may result from the low correlation between species number and traits that drive processes under observation. From standpoint litter‐quality‐dependent ecological processes, we propose litter chemical qualities are functional introduce a multivariate index diversity (CD Q ) based on Rao's quadratic entropy to describe compositional heterogeneity foliar mixtures. Using published data temperate tropical forest systems illustrate relationship...

Remotely sensed estimates of crop residue cover (fR) are required to assess the extent conservation tillage over large areas; impact decay processes on is unknown. Changes in wheat straw composition and spectral reflectance were measured during process their fR assessed. Proportions cellulose hemicellulose declined, while lignin increased. Spectral features associated with diminished decomposition. Narrow-band indices robustly estimated fR, broad-band inconsistent. Advanced multi-spectral...

Lankford , C. E. (The University of Texas, Austin), James R. Walker, B. Reeves, N. H. Nabbut, Byers, and J. Jones . Inoculum-dependent division lag Bacillus cultures its relation to an endogenous factor(s) (“schizokinen”). Bacteriol. 91: 1070–1079. 1966.—When cells megaterium grown on Brain Heart Infusion Agar, were inoculated into a chemically defined medium, they exhibited which was inverse function inoculum size. The addition filtrates from the same medium eliminated inoculum-dependent...

The objective of this work was to investigate the usefulness near infrared (NIR) reflectance spectroscopy in conjunction with a fibre-optic probe for determining various constituents (total N, organic C, active biomass and mineralisable N pH) agricultural soils. A NIRSystems model 6500 spectrometer equipped used scan soil samples ( n = 180) obtained from experimental plots at two locations three replicate under plow no till practices each location rates NH 4 NO 3 plot (2 × 2 36). For these,...