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Managing soil carbon and nitrogen for productivity and environmental quality
Author(s):Robertson, G. Philip; Knezek, Bernard D.; Paul, Eldor A.; Parker, Elaine; Smeenk, Jeffrey; Kizilkaya, Kadir; Willson, Thomas C.; Harwood, Richard R.; Jose E., Sanchez
Date Issued:2004-05
Format:born digital; articles
In this study, we investigated the impact of cropping system management on C and N pools, crop yield, and N leaching in a long-term agronomic experiment in Southwest Michigan. Four management types, conventional (CO), ...
Behavior of free amino acids in soil
Author(s):Putnam, H. D.; Schmidt, E. L.; Paul, Eldor A.
Date Issued:1960-03
Format:born digital; articles
The behavior of a mixture of amino acids in a soil environment was studied. Extractions were made with 80% ethanol. The extract was concentrated and then was analyzed for amino acids by gradient elution chromatography. ...
14C Allocation in tree–soil systems
Author(s):Paul, Eldor A.; Pregitzer, Kurt S.; Horwath, William R.
Date Issued:1994
Format:born digital; articles
We studied whole-tree C allocation with special emphasis on the quantification of C allocation to roots and root respiration. To document seasonal patterns of C allocation, 2-year-old hybrid poplar trees greater than 3 m ...
Fate of legume and fertilizer nitrogen-15 in a long-term cropping systems experiment
Author(s):Janke, Rhonda R.; Peters, Steven E.; Paul, Eldor A.; Hesterman, Oran B.; Harris, Glendon H.
Date Issued:1994-09
Format:born digital; articles
Relying more on biological N2 fixation has been suggested as a way to meet one of the major challenges of agricultural sustainability. A 15N study was conducted to compare the fate of applied legume and fertilizer N in a ...
Injection of nitrogen-15 into trees to study nitrogen cycling in soil
Author(s):Pregitzer, Kurt S.; Paul, Eldor A.; Horwath, William R.
Date Issued:1992-01
Format:born digital; articles
Most 15N dilution techniques disturb either the soil or N-pool size. The objective of this study was to develop a method of labeling the roots of Populus trees with 15N without physically disturbing the soil. Such a method ...
Visions of a more precise soil biology
Author(s):Coleman, D. C.; Paul, Eldor A.; Magid, J.; Kätterer, T.; Kirchmann, H.; Andrén, O.
Date Issued:2008-04
Format:born digital; articles
Soils have often been viewed as a black box. Soil biology is difficult to study with the precision we would wish, due to the presence of considerable soil heterogeneity, a huge diversity of organisms, and a plethora of ...
Gaseous nitrogen losses from soils under zero-till as compared with conventional-till management systems
Author(s):Paul, Eldor A.; Rennie, D. A.; Aulakh, M. S.
Date Issued:1984-01
Format:born digital; articles
The gaseous losses of N from conventional-till (CT) and zero-till (ZT) crop fields were 3 to 7 and 12 to 16 kg N ha−1 y−1, respectively. In contrast, losses from CT and ZT fallow were severalfold higher, namely, 12 to 14 ...
Organo-mineral complexes and their study by radiocarbon dating
Author(s):Paul, Eldor A.; Anderson, D. W.
Date Issued:1984-03
Format:born digital; articles
The objective of this study was to investigate the long-term cycling of organic C in cultivated soils by radiocarbon dating. Samples from a clayey Haploboroll soil (Indian Head) taken in 1963 and 1978 showed a general ...
Influence of plant residues on denitrification rates in conventional and zero tilled soils, The
Author(s):Paul, Eldor A.; Rennie, D. A.; Aulakh, M. S.
Date Issued:1984-07
Format:born digital; articles
A field study was conducted with treatments consisting of a factorial combination of N (0 or 100 kg N ha−1 as (NH4)2SO4, straw (0 or 3000 kg ha−1), and two tillage treatments. Ground straw was mixed with the plow layer of ...
Corn root effects on the nitrogen-supplying capacity of a conditioned soil
Author(s):Harwood, Richard R.; Smeenk, Jeffrey; Willson, Thomas C.; Paul, Eldor A.; Sanchez, Jose E.
Date Issued:2002-05
Format:born digital; articles
The design of sustainable N management strategies requires a better understanding of the processes influencing the ability of soils to supply N to a growing crop. Although commonly ignored, the release of C by plant roots ...