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How representatively can we sample soil mineral nitrogen?
Author(s) -
Giebel Antje,
Wendroth Ole,
Isaak Reuter Hannes,
Kersebaum KurtChristian,
Schwarz Jürgen
Publication year - 2006
Publication title -
journal of plant nutrition and soil science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 87
eISSN - 1522-2624
pISSN - 1436-8730
DOI - 10.1002/jpln.200521755
Subject(s) - sampling (signal processing) , spatial variability , soil science , spatial distribution , scale (ratio) , nitrogen , field (mathematics) , environmental science , precision agriculture , mathematics , sampling error , statistics , agriculture , observational error , chemistry , ecology , geography , cartography , computer science , biology , pure mathematics , computer vision , filter (signal processing) , organic chemistry
Spatial distribution of soil mineral‐N content (N min ) is a scale‐variant process. Precision farming assumes knowledge about the spatial distribution of N min . Moreover, sampling in management zones is based on the assumption of spatial dependence between sampling points. In the present study, variability structure of N min and the sources of variability were investigated. Within an agricultural landscape, N min was investigated across a field in a nested design over four consecutive years. Temporally unstable structure of individual nests require a sampling with several nests in the field. In the investigated field, 35%–49% of the total variability derived from small‐scale variability observed at spatial distances of <5 m and from sampling and analytical errors. Differences between 10 and 26 kg N ha –1 for the soil depth increment 0–60 cm can be expected. Uncertainty due to analytical errors were in the order of 5–10 kg N ha –1 for a 0–60 cm layer.