Details
| Original language | English |
|---|---|
| Pages (from-to) | 441-450 |
| Number of pages | 10 |
| Journal | Journal of Plant Nutrition and Soil Science |
| Volume | 165 |
| Issue number | 4 |
| Publication status | Published - 1 Aug 2002 |
Abstract
The objective of this study was to experimentally investigate net N mineralization in sandy arable soils and to derive adequate N mineralization parameters for simulation purposes. Long-term incubations at 35°C were done for at least 200 days with 147 sandy arable soils from Northwest Germany. To cumulative net N mineralization curves the simultaneous two-pool first-order kinetic equation was fitted in order to differentiate between N mineralization from an easily decomposable, fresh organic matter pool (Nfast) and from a slowly decomposable pool (Nslow) of more humified OM. North German loess soils served as a reference, since available model parameters were mainly derived from those soils. Although curve patterns in sandy soils often somewhat deviated from typical double-exponential patterns, the mineralization equation generally could be fitted. Two pools were clearly revealed, but a transfer of the standard parameters was found to be not appropriate - except maybe for the pool size of the fast decomposable N pool. The mean k fast at 35°C (0.1263 d-1) is about 46% higher than the known 'standard' loess value, indicating better conditions for decomposition of fresh residues at this temperature. The mean kslow at 35°C (0.0023 d-1), which is 60% lower than reported earlier from loess soils, and much lower mineralization rates of the slowly decomposable N pool give reason to the presence of generally more resistant organic material in these sandy soils. The relation between Nslow and total N was found to be not close enough to derive the pool size of slowly decomposable N just from total N as done for loess soils. Reducing the variability is necessary, promising approaches exist. The eight reference loess soils revealed - on an average - the known N mineralization parameters.
Keywords
- Curve-splitting, Long-term incubation, Model parameters, Net N mineralization, Sandy arable soils
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)
- Soil Science
- Agricultural and Biological Sciences(all)
- Plant Science
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In: Journal of Plant Nutrition and Soil Science, Vol. 165, No. 4, 01.08.2002, p. 441-450.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - N mineralization parameters of sandy arable soils
AU - Heumann, Sabine
AU - Böttcher, Jürgen
AU - Springob, Günther
N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2002/8/1
Y1 - 2002/8/1
N2 - The objective of this study was to experimentally investigate net N mineralization in sandy arable soils and to derive adequate N mineralization parameters for simulation purposes. Long-term incubations at 35°C were done for at least 200 days with 147 sandy arable soils from Northwest Germany. To cumulative net N mineralization curves the simultaneous two-pool first-order kinetic equation was fitted in order to differentiate between N mineralization from an easily decomposable, fresh organic matter pool (Nfast) and from a slowly decomposable pool (Nslow) of more humified OM. North German loess soils served as a reference, since available model parameters were mainly derived from those soils. Although curve patterns in sandy soils often somewhat deviated from typical double-exponential patterns, the mineralization equation generally could be fitted. Two pools were clearly revealed, but a transfer of the standard parameters was found to be not appropriate - except maybe for the pool size of the fast decomposable N pool. The mean k fast at 35°C (0.1263 d-1) is about 46% higher than the known 'standard' loess value, indicating better conditions for decomposition of fresh residues at this temperature. The mean kslow at 35°C (0.0023 d-1), which is 60% lower than reported earlier from loess soils, and much lower mineralization rates of the slowly decomposable N pool give reason to the presence of generally more resistant organic material in these sandy soils. The relation between Nslow and total N was found to be not close enough to derive the pool size of slowly decomposable N just from total N as done for loess soils. Reducing the variability is necessary, promising approaches exist. The eight reference loess soils revealed - on an average - the known N mineralization parameters.
AB - The objective of this study was to experimentally investigate net N mineralization in sandy arable soils and to derive adequate N mineralization parameters for simulation purposes. Long-term incubations at 35°C were done for at least 200 days with 147 sandy arable soils from Northwest Germany. To cumulative net N mineralization curves the simultaneous two-pool first-order kinetic equation was fitted in order to differentiate between N mineralization from an easily decomposable, fresh organic matter pool (Nfast) and from a slowly decomposable pool (Nslow) of more humified OM. North German loess soils served as a reference, since available model parameters were mainly derived from those soils. Although curve patterns in sandy soils often somewhat deviated from typical double-exponential patterns, the mineralization equation generally could be fitted. Two pools were clearly revealed, but a transfer of the standard parameters was found to be not appropriate - except maybe for the pool size of the fast decomposable N pool. The mean k fast at 35°C (0.1263 d-1) is about 46% higher than the known 'standard' loess value, indicating better conditions for decomposition of fresh residues at this temperature. The mean kslow at 35°C (0.0023 d-1), which is 60% lower than reported earlier from loess soils, and much lower mineralization rates of the slowly decomposable N pool give reason to the presence of generally more resistant organic material in these sandy soils. The relation between Nslow and total N was found to be not close enough to derive the pool size of slowly decomposable N just from total N as done for loess soils. Reducing the variability is necessary, promising approaches exist. The eight reference loess soils revealed - on an average - the known N mineralization parameters.
KW - Curve-splitting
KW - Long-term incubation
KW - Model parameters
KW - Net N mineralization
KW - Sandy arable soils
UR - http://www.scopus.com/inward/record.url?scp=0141941032&partnerID=8YFLogxK
U2 - 10.1002/1522-2624(200208)165:4<441::AID-JPLN441>3.0.CO;2-F
DO - 10.1002/1522-2624(200208)165:4<441::AID-JPLN441>3.0.CO;2-F
M3 - Article
AN - SCOPUS:0141941032
VL - 165
SP - 441
EP - 450
JO - Journal of Plant Nutrition and Soil Science
JF - Journal of Plant Nutrition and Soil Science
SN - 1436-8730
IS - 4
ER -