How Representatively Can We Sample Soil Mineral Nitrogen

Spatial distribution of soil mineral nitrogen content (Nmin) is a scale variant process. Precision farming assumes knowledge about the spatial distribution of mineral soil nitrogen content. Moreover sampling in management zones is based on the assumption of spatial dependence between sampling points. In the present study, variabilit structure of Nmin and the source of variability were investigated. Within an agricultural landscape, Nmin was investigated across a field in a nested design over four consecutive years. Temporally unstable structure of individual nests require a sampling with several nets in the field. In the investigated field, 35-49% of the total variability derived from small-scale variability observed at spatial distances of less than 5m and from sampling and analytical errors. Differences between 10 and 29 kg N ha-1 for the soil depth increment 0-60 cm can be expected. Uncertainty due to analytical errors were in order of 5-10 kg N ha-1 for a 0-60 cm layer.

WENDROTH Ole;  REUTER Hannes Isaak; 

2006-12-06

WILEY-V C H VERLAG GMBH

JRC32363

https://publications.jrc.ec.europa.eu/repository/handle/JRC32363,   

10.1002/jpln.200521755,