In:
Soil Science Society of America Journal, Wiley, Vol. 68, No. 2 ( 2004-03), p. 644-653
Kurzfassung:
Fertilizer and manure P applications together with cropping practices can have a lasting effect on soil fertility and can result in pollution of waterways. This study was aimed at providing a general model for the long‐term changes in soil P extracted with conventional tests. The model maintains three active pools of soil P: extractable soil P (X), absorbed P that is not extractable but interchanges reversibly with X (Y), and mineral P that provides solubility‐product type buffering of X (P buffer ). There is also an input for the net P addition. Equations derived from the model define most of the published patterns of response of X found in long‐term field experiments. They underpin a dynamic version of the model that permits annual inputs and calculates the time‐course of the various P pools. A method was devised for calibrating the dynamic version from measurements that are usually made in long‐term experiments. Models calibrated in this way gave good fits to the data from six soils from four countries. Values of the coefficients indicated that solubility product buffering had a decisive influence on the P economy of some but not all soils. The model gave predictions of X that were in good agreement with measurements in three long‐term experiments that were entirely independent of those used for calibrating the model. Other possible methods of calibration are discussed. The model concisely represents key factors affecting the dynamics of X over the long term and has both interpretative and predictive value.
Materialart:
Online-Ressource
ISSN:
0361-5995
,
1435-0661
DOI:
10.2136/sssaj2004.6440
Sprache:
Englisch
Verlag:
Wiley
Publikationsdatum:
2004
ZDB Id:
241415-6
ZDB Id:
2239747-4
ZDB Id:
196788-5
ZDB Id:
1481691-X
SSG:
13
SSG:
21
