Field-specific simulations of net N mineralization based on digitally available soil and weather data

II. Pedotransfer functions for the pool sizes

verfasst von

Sabine Heumann, Horst Ringe, Jürgen Böttcher

Abstract

Avoiding surplus N fertilization without reducing crop yields could be accomplished by accounting for current net N mineralization in N fertilizer recommendations. N simulation models would allow a quantitative consideration of important factors and could be based upon digitally mapped data. Soil-specific temperature and water functions that were derived in part I of the paper needed a differentiation between only three soil groups and the two allocating criteria were taken from digital soil maps. Here, the objectives were to experimentally determine pedotransfer functions (PTFs) for the pool sizes of two organic N pools (N_fast, N_slow) that could be calculated via digitally available data and need a minimum set of easily accessible management data. Interestingly, most important input data for the PTFs of both pool sizes were mean clay contents of the texture class (German soil classification system). However, the underlying mechanisms might be different, as N_slow could be positively influenced by clay-associated mineralizable SOM, whereas N_fast could be positively related to clay content due to higher yield potential and thus more residues on finer-textured soils. For N_slow including the humus class improved the accuracy of the PTF (r² = 0.60; P < 0.050). For N_fast it was important to include a negative influence of the mean fall temperature of the preceding year (r² = 0.42; P < 0.010), probably due to its influence on residue degradation before winter. Surprisingly, easily accessible management data, e.g. previous crop, did not improve the predictions in this study. Field studies with plant cover will have to further prove the applicability of the derived PTFs.

Organisationseinheit(en)

Institut für Bodenkunde
AG Bodenbiophysik

Externe Organisation(en)

Johann Heinrich von Thünen-Institut, Bundesforschungsinstitut für Ländliche Räume, Wald und Fischerei

Typ

Artikel

Journal

Nutrient cycling in agroecosystems

Band

91

Seiten

339-350

Anzahl der Seiten

12

ISSN

1385-1314

Publikationsdatum

12.2011

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Agronomie und Nutzpflanzenwissenschaften, Bodenkunde

Ziele für nachhaltige Entwicklung

SDG 2 – Kein Hunger

Elektronische Version(en)

https://doi.org/10.1007/s10705-011-9465-x (Zugang: Unbekannt)