@article{fdi:010036698,
  title = {{I}mpact of {DEM} mesh size and soil map scale on {SWAT} runoff, sediment, and {NO}3-{N} loads predictions},
  author = {{C}haplot, {V}incent},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he accuracy of agricultural nonpoint source pollution models depends to a great extent on how well model input spatial parameters describe the relevant characteristics of the watershed. {I}t is assumed that reducing the precision of spatial input parameters affects the simulation results of runoff and sediment yield from the entire watershed. {H}owever, there may be no significant increase in the accuracy of models, as a result of more precise topographic or soil information, which increase the input data collection and preparation. {T}he objective of this study was to determine the impact of the mesh size of the digital elevation model, {DEM} (from 20 to 500 m) and the soil map scale (1/25,000; 1/250,000 and; 1/500,000 scale) within the {S}oil and {W}ater {A}nalysis {T}ool ({SWAT}) to simulate runoff, sediment, and {NO}3-{N} loads at the outlet of an agricultural watershed. {R}esults of the {L}ower {W}alnut {C}reek (21.8 km(2), central {I}owa) showed that an upper limit to {DEM} mesh size of 50 m is required to simulate watershed loads. {D}ecreasing the mesh size beyond this threshold does not substantially affect the computed runoff flux but generated prediction errors for nitrogen and sediment yields. {W}hatever the {DEM} mesh size considered, a detailed soil map has to be considered to accurately estimate the loads. {F}inally, the impacts of {DEM} mesh size and soil map scale on the modeling results are discussed in respect of the relevant characteristics of the watershed and included in {SWAT}. (c) 2005 {E}lsevier {B}.{V}. {A}ll rights reserved.},
  keywords = {hydrologic modeling ; {SWAT} ; spatial input data ; {DEM} ; soil map},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {312},
  numero = {1-4},
  pages = {207--222},
  ISSN = {0022-1694},
  year = {2005},
  DOI = {10.1016/j.jhydrol.2005.02.017},
  URL = {https://www.documentation.ird.fr/hor/fdi:010036698},
}