| Title |
Plant availability of secondary phosphates depending on pH in a peat -based growing medium |
| ID_Doc |
23965 |
| Authors |
Hauck, D; Lohr, D; Meinken, E; Schmidhalter, U |
| Title |
Plant availability of secondary phosphates depending on pH in a peat -based growing medium |
| Year |
2021 |
| Published |
|
| DOI |
10.17660/ActaHortic.2021.1305.57 |
| Abstract |
Phosphorus (P) fertilizer consumption will deplete global reserves of rock phosphate within the next few centuries. Several technologies have been developed within the last decade to recover phosphate from P-rich waste streams. Recycling P fertilizers (secondary phosphates) is gaining increasing interest but little is known about the possible use of such products in soilless plant production systems. In this study, a greenhouse experiment with Tagetes patula x T erecta 'Fi Zenith Red' as P sensitive model plant was conducted to determine the plant availability of three secondary phosphates: precipitated magnesia ammonium phosphate (Struvite), sewage sludge ash (SSA) and metallurgic granulate (Mephrec). Water soluble monocalcium phosphate (CaP) and rock phosphate (rock-P) were included as controls. The growing medium was peat limed to two pH levels (4.5-5.0, 5.5-6.0). Calcium chloride/DTPA (CAT) and calcium -acetate -lactate (CAL) soluble P was extracted at the beginning of the experiment to test if these solvents were suitable to predict plant availability of the P fertilizers. After 6 weeks of cultivation, dry matter and P uptake of the plants were determined. Ranking of dry weight at pH 4.5-5.5 was CaP = Struvite = SSA = rock-P >> Mephrec and at pH 5.5-6.0 CaP = Struvite > SSA > rock-P > Mephrec. Ranking of plant P uptake was Struvite > CaP > SSA=rock-P >> Mephrec at pH 4.5-5.5 and Struvite > CaP >> SSA=rock-P > Mephrec at pH 5.5-6.0. Among plants fertilized with SSA or rock-P, a significant increase in dry weight and P uptake was found by decreasing the pH from 5.5 to 6.0 to 4.5-5.5 in the growing medium. In comparison to CAL, CAT extracted a slightly lower amount of P from the growing medium. Neither CAT nor CAL was able to predict the increased P uptake from SSA and rock-P at pH 4.5-5.0. |
| Author Keywords |
circular economy; fertilization; waste streams; ornamentals rock-P |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Conference Proceedings Citation Index - Science (CPCI-S) |
| EID |
WOS:000711411200057 |
| WoS Category |
Agronomy; Horticulture; Soil Science |
| Research Area |
Agriculture |
| PDF |
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