PLoS ONE (Jan 2016)

Impact of Spatial Soil and Climate Input Data Aggregation on Regional Yield Simulations.

  • Holger Hoffmann,
  • Gang Zhao,
  • Senthold Asseng,
  • Marco Bindi,
  • Christian Biernath,
  • Julie Constantin,
  • Elsa Coucheney,
  • Rene Dechow,
  • Luca Doro,
  • Henrik Eckersten,
  • Thomas Gaiser,
  • Balázs Grosz,
  • Florian Heinlein,
  • Belay T Kassie,
  • Kurt-Christian Kersebaum,
  • Christian Klein,
  • Matthias Kuhnert,
  • Elisabet Lewan,
  • Marco Moriondo,
  • Claas Nendel,
  • Eckart Priesack,
  • Helene Raynal,
  • Pier P Roggero,
  • Reimund P Rötter,
  • Stefan Siebert,
  • Xenia Specka,
  • Fulu Tao,
  • Edmar Teixeira,
  • Giacomo Trombi,
  • Daniel Wallach,
  • Lutz Weihermüller,
  • Jagadeesh Yeluripati,
  • Frank Ewert

DOI
https://doi.org/10.1371/journal.pone.0151782
Journal volume & issue
Vol. 11, no. 4
p. e0151782

Abstract

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We show the error in water-limited yields simulated by crop models which is associated with spatially aggregated soil and climate input data. Crop simulations at large scales (regional, national, continental) frequently use input data of low resolution. Therefore, climate and soil data are often generated via averaging and sampling by area majority. This may bias simulated yields at large scales, varying largely across models. Thus, we evaluated the error associated with spatially aggregated soil and climate data for 14 crop models. Yields of winter wheat and silage maize were simulated under water-limited production conditions. We calculated this error from crop yields simulated at spatial resolutions from 1 to 100 km for the state of North Rhine-Westphalia, Germany. Most models showed yields biased by <15% when aggregating only soil data. The relative mean absolute error (rMAE) of most models using aggregated soil data was in the range or larger than the inter-annual or inter-model variability in yields. This error increased further when both climate and soil data were aggregated. Distinct error patterns indicate that the rMAE may be estimated from few soil variables. Illustrating the range of these aggregation effects across models, this study is a first step towards an ex-ante assessment of aggregation errors in large-scale simulations.