Measurement of the nitrogen supply via mineralization in field-grown spinach
- The mineralization of soil organic nitrogen (N) and crop residues can significantly contribute to the N supply of vegetable crops. However, short-term mineralization dynamics are difficult to predict. On the other hand, fast-growing crops like spinach are highly sensitive to N shortage. Therefore, in situ soil columns have been tested to estimate the actual N supply via mineralization in field-grown spinach. In ten fertilization trials covered soil columns (20 cm in diameter) were driven into the soil to a depth of 30 cm at the start of the cultivation. Eight columns were repeated in three blocks within a total trial area of 0.10 to 0.25 ha. Net N mineralization was derived by subtracting the soil mineral N concentration (Nmin) in the upper 30 cm before installation from the concentration inside the columns at harvest. For comparison, a balance sheet was calculated for spinach plots receiving no N fertilization (zero plots) as well as fertilized plots and used as a proxy for net N mineralization. In this approach the initial Nmin concentration in the upper 30 cm of the soil, the N supply via irrigation, and fertilization as well as the total aboveground N uptake by spinach and the Nmin residue were considered. By using soil columns, N mineralization was determined with a mean coefficient of variation of 18%. A higher spatial variability of up to 43% was observed when spinach was grown as a second crop. The average net N mineralization rate ranged between 2 kg ha‑1 week‑1 (0-30 cm) in winter-grown spinach and 3-7 kg ha‑1 week‑1 (0-30 cm) in the other seasons. Nitrogen mineralization measured by the soil columns was qualitatively confirmed with the data obtained by the balance sheet. Soil columns enable repeated samplings during the spinach cultivation. In this way, top dressing rates can be adjusted to the actual N supply.
Author: | Christian FrerichsORCiD, Diemo DaumORCiD |
---|---|
Title (English): | Measurement of the nitrogen supply via mineralization in field-grown spinach |
DOI: | https://doi.org/10.17660/ActaHortic.2023.1375.13 |
ISBN: | 978-94-62613-74-4 |
Parent Title (English): | Proceedings of the International Symposium on Plant Nutrition, Fertilization, Soil Management |
Publisher: | International Society for Horticultural Science (ISHS) |
Document Type: | Part of a Book |
Language: | English |
Year of Completion: | 2023 |
Release Date: | 2024/01/22 |
Tag: | Balance sheet; Crop residues; N recovery; Soil columns; Spinach (Spinacia oleracea L.); Top dressing; Zero plots |
First Page: | 97 |
Last Page: | 104 |
Note: | XXXI International Horticultural Congress (IHC2022): International Symposium on Plant Nutrition, Fertilization, Soil Management, 14.08. - 20.02.2022, Angers (France) |
Faculties: | Fakultät AuL |
DDC classes: | 600 Technik, Medizin, angewandte Wissenschaften / 630 Landwirtschaft, Veterinärmedizin |
Review Status: | Veröffentlichte Fassung/Verlagsversion |