Details
Originalsprache | Englisch |
---|---|
Seiten (von - bis) | 155-164 |
Seitenumfang | 10 |
Fachzeitschrift | Journal of Plant Nutrition and Soil Science |
Jahrgang | 178 |
Ausgabenummer | 1 |
Publikationsstatus | Veröffentlicht - 1 Feb. 2015 |
Abstract
Peat is commonly used as the main component of horticultural substrates, but it has a very low buffering capacity for the anionic macronutrient phosphorus (P), which can be increased by the addition of clays. The aim of this study was to characterize the P adsorption capacity of different substrate clays and to evaluate its significance for plant P uptake. Substrate clays were characterized with a single-point batch experiment and adsorption and desorption isotherms. The data were fitted to the Langmuir equation for a calculation of the maximum adsorption capacity. Additionally, the contents of oxalate extractable Fe and Al (ΣFeox + Alox) were determined. The influence of a varying P adsorption capacity of the clays on the P availability to plants in the respective peat-clay substrates and pure peat was investigated in a growth experiment with Impatiens walleriana fertigated with 0, 17, and 35 mgP L-1 solution, respectively. The observed and calculated (Langmuir) P adsorption capacity of the clays could be well-characterized by both the batch experiment and the adsorption isotherms and was highly correlated with the ΣFeox+Alox. A higher P adsorption capacity of the clay amendment in mixed substrates resulted in a lower P concentration in the substrate solution, while the CAT extractable P concentration (PCAT) was the same. Plant growth and shoot P concentrations were enhanced in the substrates, showing a higher P adsorption capacity, since plants were able to take up the whole amount of PCAT, and also part of the non-CAT extractable P. However, the release rate was too low to ensure optimal plant growth, which was in accordance with the result of the desorption experiment. The absolute extent of P release was increased with the increasing P adsorption capacity of the clays and higher degree of P saturation (DPS).
ASJC Scopus Sachgebiete
- Agrar- und Biowissenschaften (insg.)
- Bodenkunde
- Agrar- und Biowissenschaften (insg.)
- Pflanzenkunde
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in: Journal of Plant Nutrition and Soil Science, Jahrgang 178, Nr. 1, 01.02.2015, S. 155-164.
Publikation: Beitrag in Fachzeitschrift › Artikel › Forschung › Peer-Review
}
TY - JOUR
T1 - Phosphorus buffering capacity of substrate clays and its significance for plant cultivation
AU - Binner, Inga
AU - Dultz, Stefan
AU - Schenk, Manfred K.
N1 - Publisher Copyright: © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Copyright: Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2015/2/1
Y1 - 2015/2/1
N2 - Peat is commonly used as the main component of horticultural substrates, but it has a very low buffering capacity for the anionic macronutrient phosphorus (P), which can be increased by the addition of clays. The aim of this study was to characterize the P adsorption capacity of different substrate clays and to evaluate its significance for plant P uptake. Substrate clays were characterized with a single-point batch experiment and adsorption and desorption isotherms. The data were fitted to the Langmuir equation for a calculation of the maximum adsorption capacity. Additionally, the contents of oxalate extractable Fe and Al (ΣFeox + Alox) were determined. The influence of a varying P adsorption capacity of the clays on the P availability to plants in the respective peat-clay substrates and pure peat was investigated in a growth experiment with Impatiens walleriana fertigated with 0, 17, and 35 mgP L-1 solution, respectively. The observed and calculated (Langmuir) P adsorption capacity of the clays could be well-characterized by both the batch experiment and the adsorption isotherms and was highly correlated with the ΣFeox+Alox. A higher P adsorption capacity of the clay amendment in mixed substrates resulted in a lower P concentration in the substrate solution, while the CAT extractable P concentration (PCAT) was the same. Plant growth and shoot P concentrations were enhanced in the substrates, showing a higher P adsorption capacity, since plants were able to take up the whole amount of PCAT, and also part of the non-CAT extractable P. However, the release rate was too low to ensure optimal plant growth, which was in accordance with the result of the desorption experiment. The absolute extent of P release was increased with the increasing P adsorption capacity of the clays and higher degree of P saturation (DPS).
AB - Peat is commonly used as the main component of horticultural substrates, but it has a very low buffering capacity for the anionic macronutrient phosphorus (P), which can be increased by the addition of clays. The aim of this study was to characterize the P adsorption capacity of different substrate clays and to evaluate its significance for plant P uptake. Substrate clays were characterized with a single-point batch experiment and adsorption and desorption isotherms. The data were fitted to the Langmuir equation for a calculation of the maximum adsorption capacity. Additionally, the contents of oxalate extractable Fe and Al (ΣFeox + Alox) were determined. The influence of a varying P adsorption capacity of the clays on the P availability to plants in the respective peat-clay substrates and pure peat was investigated in a growth experiment with Impatiens walleriana fertigated with 0, 17, and 35 mgP L-1 solution, respectively. The observed and calculated (Langmuir) P adsorption capacity of the clays could be well-characterized by both the batch experiment and the adsorption isotherms and was highly correlated with the ΣFeox+Alox. A higher P adsorption capacity of the clay amendment in mixed substrates resulted in a lower P concentration in the substrate solution, while the CAT extractable P concentration (PCAT) was the same. Plant growth and shoot P concentrations were enhanced in the substrates, showing a higher P adsorption capacity, since plants were able to take up the whole amount of PCAT, and also part of the non-CAT extractable P. However, the release rate was too low to ensure optimal plant growth, which was in accordance with the result of the desorption experiment. The absolute extent of P release was increased with the increasing P adsorption capacity of the clays and higher degree of P saturation (DPS).
KW - Batch experiment
KW - CAT extraction
KW - Degree of P saturation
KW - Peat-clay blend
KW - Phosphorus adsorption
UR - http://www.scopus.com/inward/record.url?scp=84922212367&partnerID=8YFLogxK
U2 - 10.1002/jpln.201400523
DO - 10.1002/jpln.201400523
M3 - Article
AN - SCOPUS:84922212367
VL - 178
SP - 155
EP - 164
JO - Journal of Plant Nutrition and Soil Science
JF - Journal of Plant Nutrition and Soil Science
SN - 1436-8730
IS - 1
ER -