%0 Journal Article
%T Predicting Mineral N Release during Decomposition of Organic Wastes in Soil by Use of the SOILN_NO Model
%A Trine A. Sogn
%A Lars Egil Haugen
%J Applied and Environmental Soil Science
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/161079
%X In order to predict the mineral N release associated with the use of organic waste as fertilizer in agricultural plant production, the adequacy of the SOILN_NO model has been evaluated. The original thought was that the model calibrated to data from simple incubation experiments could predict the mineral N release from organic waste products used as N fertilizer on agricultural land. First, the model was calibrated to mineral N data achieved in a laboratory experiment where different organic wastes were added to soil and incubated at 15¡ãC for 8 weeks. Secondly, the calibrated model was tested by use of NO3£¿£¿ leaching data from soil columns with barley growing in 4 different soil types, added organic waste and exposed to natural climatic conditions during three growing seasons. The SOILN_NO model reproduced relatively well the NO3£¿£¿ leaching from some of the soils included in the outdoor experiment, but failed to reproduce others. Use of the calibrated model often induced underestimation of the observed NO3£¿£¿ leaching. To achieve a satisfactory simulation of the NO3£¿£¿ leaching, recalibration of the model had to be carried out. Thus, SOILN_NO calibrated to data from simple incubation experiments in the laboratory could not directly be used as a tool to predict the N-leaching following organic waste application in more natural agronomic plant production systems. The results emphasised the need for site- and system-specific data for model calibration before using a model for predictive purposes related to fertilizer N value of organic wastes applied to agricultural land. 1. Introduction In order to achieve sustainable food production there is a high focus on recycling of nutrients by utilisation of organic waste as a fertilizer in agricultural plant production. Effective and safe use of organic wastes in agricultural plant production requires risks and benefits to be weighed and documented. Heavy metal and organic contaminant accumulation, as well as transmission of pathogenic bacteria, are among the identified risks. These risks are continuously managed by advances in the waste processing technology. On the other hand, obvious positive effects of organic waste application on soil structure, porosity, water retention capability, cation exchange capacity, and biological activity have been identified, for example [1, 2]. The nutrient value of organic waste has shown to be dependent of type of waste, both origin and processing method [3]. A general condition for using organic wastes as fertilizers is the ability to predict their mineralization dynamics during
%U http://www.hindawi.com/journals/aess/2011/161079/