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Use of tracers and computer simulation techniques to assess mineralization and immobilization of soil nitrogen
Contributor:Paul, Eldor A.; Juma, N. G.
The objectives of this investigation were to develop and test concepts of microbial growtth and decay in soil and to study the mineralization and inmobilization of soil N using tracer and computer simulation techniques.
Measuring and monitoring soil organic carbon stocks in agricultural lands for climate mitigation
Contributor:Paul, Eldor A.; Ogle, Stephen M.; Conant, Richard; Paustian, Keith
Policies that encourage greenhouse-gas emitters to mitigate emissions through terrestrial carbon (C) offsets – C sequestration in soils or biomass – will promote practices that reduce erosion and build soil fertility, while ...
Effect of soil moisture stress on uptake and recovery of tagged nitrogen by wheat
Contributor:Paul, E. A.; Myers, R. J. K.
Labelled 15NH4NO3 was used in a growth chamber to study the effect of moisture stress on the utilization of nitrogen by wheat. This made it possible to determine the recovery of nitrogen (N) in the soil-plant system of two ...
Estimation of slow- and fast-cycling soil organic carbon pools from 6N HCI hydrolysis
Contributor:Leavitt, S. W.; Follett, R. F.; Paul, E. A.
Acid hydrolysis is used to fractionate the soil organic carbon pool into relatively slow- and fast-cycling compartments on soils from Arizona, the Great Plains states and Michigan collected for carbon isotope tracer studies ...
Diffuse-reflectance Fourier-transform mid-infrared spectroscopy as a method of characterizing changes in soil organic matter
Contributor:Haddix, Michelle; Margrini-Bair, Kimberly; Conant, Richard; Calderón, Francisco; Paul, Eldor A.
Diffuse-reflectance Fourier-transform mid-infrared spectroscopy (MidIR) can identify the presence of important organic functional groups in soil organic matter (SOM); however, spectral interpretation needs to be validated ...
Effects of agronomic treatments on structure and function of ammonia-oxidizing communities
Contributor:Phillips, Carol J.; Paul, Eldor A.; Prosser, James I.; Gross, Katherine L.; Dollhopf, Sherry L.; Harris, Dave
The aim of this study was to determine the effects of different agricultural treatments and plant communities on the diversity of ammonia oxidizer populations in soil. Denaturing gradient gel electrophoresis (DGGE), coupled ...
Extraction and charaterization of humus with reference to clay-associated humus
Contributor:Anderson, D. W.; Paul, E. A.; St. Arnaud, R. J.
An extraction-fractionation method was developed with which it is possible to isolate 60–67% of the humus of Chernozemic and Luvisolic soils. Two humic acid fractions were obtained: (1) a conventional alkali-pyrophosphate ...
Response of mycorrhizal and P-fertilized soybeans to nodulation by Bradyrhizobium or ammonium nitrate
Contributor:Paul, Eldor A.; Pacovsky, R. S.; Bethlenfalvay, G. J.
Management of N2-fixing bacteria or P-scavenging endomycorrhizae may lead to decreased fertilizer use on extensively cropped lands. To measure the effectiveness of these microsymbionts, soybean [Glycine max (L.) Merr. cv. ...
Spectrophotometric measurement of soil color and its relationship to moisture and organic matter
Contributor:Paul, E. A.; Shields, J. A.; Head, W. K.; St. Arnaud, R. J.
The color of soil samples taken from the Ap horizons of Chernozemic and Gray Wooded (Podzolic) soils was measured spectrophotometrically at moisture levels ranging from air-dryness to field capacity. The Munsell re-notations ...
Investigations of the dynamics of soil humus utilizing carbon dating techniques
Contributor:Rennie, D. A.; Campbell, C. A.; Paul, Eldor A.; McCallum, K. J.
The radioactivity of naturally occurring C14 in soil humus when compared to the C14 activity of a standard of recent origin (carbon dating) can be used to estimate the mean residence time of the soil humus in studying ...