Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH
Sewage sludge ash (SSA) as a secondary phosphorus (P) source may help to conserve global rock phosphate deposits if used in the base fertilization of soilless growing media. Plant availability of SSA-P was studied in a pot experiment with marigolds in a peat-based growing medium of contrasting pH (4...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Agronomy |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4395/12/11/2610 |
| _version_ | 1797469511517995008 |
|---|---|
| author | Daniel Hauck Dieter Lohr Elke Meinken Urs Schmidhalter |
| author_facet | Daniel Hauck Dieter Lohr Elke Meinken Urs Schmidhalter |
| author_sort | Daniel Hauck |
| collection | DOAJ |
| description | Sewage sludge ash (SSA) as a secondary phosphorus (P) source may help to conserve global rock phosphate deposits if used in the base fertilization of soilless growing media. Plant availability of SSA-P was studied in a pot experiment with marigolds in a peat-based growing medium of contrasting pH (4.5, 6.0). Six SSAs were included in the study and compared to water-soluble monocalcium phosphate (MCP) and rock phosphate (RockP). In addition to the efficacy of SSA-P, calcium chloride + diethylenetriaminepentaacetate (CAT) and calcium-acetate-lactate (CAL), as commonly used extractants in Germany to analyze plant-available P in growing media, were tested in terms of their ability to predict plant P uptake. No SSA reached the relative P use efficiency (rPUE) observed for MCP. However, at a growing medium pH of 4.5, the average rPUE for SSA was 70% of the MCP rPUE. Compared to RockP, at a growing medium pH of 6.0, SSAs resulted in an rPUE of nearly the same low level. In contrast, at pH 4.5, the rPUE from SSAs was mostly lower than that from RockP, and there were differences in rPUE among SSA origins. Therefore, in addition to a variation in particle size distribution, there might be differences in the P-bearing phase. Sewage sludge ashes represent a promising substitute for primary P sources only in crops requiring a low pH in the growing medium. The extractants CAT and CAL, on their own or in combination, did not reflect plant P uptake from SSA. To improve the prediction of plant-available SSA-P, solvent modifications or additional extractants might be promising and should be subjected to further research. |
| first_indexed | 2024-03-09T19:22:25Z |
| format | Article |
| id | doaj.art-e2c78a41e9624d97802aa8698f67ced4 |
| institution | Directory Open Access Journal |
| issn | 2073-4395 |
| language | English |
| last_indexed | 2024-03-09T19:22:25Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Agronomy |
| spelling | doaj.art-e2c78a41e9624d97802aa8698f67ced42023-11-24T03:19:13ZengMDPI AGAgronomy2073-43952022-10-011211261010.3390/agronomy12112610Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pHDaniel Hauck0Dieter Lohr1Elke Meinken2Urs Schmidhalter3Institute of Horticulture, Weihenstephan-Triesdorf University of Applied Sciences, Am Staudengarten 14, 85354 Freising, GermanyInstitute of Horticulture, Weihenstephan-Triesdorf University of Applied Sciences, Am Staudengarten 14, 85354 Freising, GermanyInstitute of Horticulture, Weihenstephan-Triesdorf University of Applied Sciences, Am Staudengarten 14, 85354 Freising, GermanyChair of Plant Nutrition, Technical University Munich, Emil-Ramann-Straße 2, 85354 Freising, GermanySewage sludge ash (SSA) as a secondary phosphorus (P) source may help to conserve global rock phosphate deposits if used in the base fertilization of soilless growing media. Plant availability of SSA-P was studied in a pot experiment with marigolds in a peat-based growing medium of contrasting pH (4.5, 6.0). Six SSAs were included in the study and compared to water-soluble monocalcium phosphate (MCP) and rock phosphate (RockP). In addition to the efficacy of SSA-P, calcium chloride + diethylenetriaminepentaacetate (CAT) and calcium-acetate-lactate (CAL), as commonly used extractants in Germany to analyze plant-available P in growing media, were tested in terms of their ability to predict plant P uptake. No SSA reached the relative P use efficiency (rPUE) observed for MCP. However, at a growing medium pH of 4.5, the average rPUE for SSA was 70% of the MCP rPUE. Compared to RockP, at a growing medium pH of 6.0, SSAs resulted in an rPUE of nearly the same low level. In contrast, at pH 4.5, the rPUE from SSAs was mostly lower than that from RockP, and there were differences in rPUE among SSA origins. Therefore, in addition to a variation in particle size distribution, there might be differences in the P-bearing phase. Sewage sludge ashes represent a promising substitute for primary P sources only in crops requiring a low pH in the growing medium. The extractants CAT and CAL, on their own or in combination, did not reflect plant P uptake from SSA. To improve the prediction of plant-available SSA-P, solvent modifications or additional extractants might be promising and should be subjected to further research.https://www.mdpi.com/2073-4395/12/11/2610fertilizationhorticulturephosphorus recyclingmonoincineration ashpH effectsecondary P source |
| spellingShingle | Daniel Hauck Dieter Lohr Elke Meinken Urs Schmidhalter Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH Agronomy fertilization horticulture phosphorus recycling monoincineration ash pH effect secondary P source |
| title | Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH |
| title_full | Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH |
| title_fullStr | Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH |
| title_full_unstemmed | Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH |
| title_short | Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH |
| title_sort | phosphorus availability from german sewage sludge ashes to plants cultivated in soilless growing media of contrasting ph |
| topic | fertilization horticulture phosphorus recycling monoincineration ash pH effect secondary P source |
| url | https://www.mdpi.com/2073-4395/12/11/2610 |
| work_keys_str_mv | AT danielhauck phosphorusavailabilityfromgermansewagesludgeashestoplantscultivatedinsoillessgrowingmediaofcontrastingph AT dieterlohr phosphorusavailabilityfromgermansewagesludgeashestoplantscultivatedinsoillessgrowingmediaofcontrastingph AT elkemeinken phosphorusavailabilityfromgermansewagesludgeashestoplantscultivatedinsoillessgrowingmediaofcontrastingph AT ursschmidhalter phosphorusavailabilityfromgermansewagesludgeashestoplantscultivatedinsoillessgrowingmediaofcontrastingph |