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| Volume 106(2) 2006, pages: 75-85. | | Anita Veihe, Niels H. Jensen, Eva Boegh, Peter Frederiksen & Michael W. Pedersen: | Sensitivity of DaisyGIS to LAI: Implications for land use based modelling of nitrate leaching | | Scaling is an important issue when measuring, modelling and understanding
coupled socio-environmental terrestrial systems. Scaling
may be enhanced through the incorporation of remotely sensed
data. This paper assesses the sensitivity of DaisyGIS to changes in
the Leaf Area Index (LAI) and discusses the implications for land
use based modelling of nitrate leaching using remote sensing based
LAI estimates. It is shown how DaisyGIS simulates nitrate leaching
quite well over the period 2001 to 2004 except for one plot during
a season with winter rape. It was found that the model is sensitive
to changes in LAI with increases of up to 262% on nitrate leaching
rates when reducing LAI by 15%. At the same time, the nitrate
leaching rates at the field level vary considerably due to local
changes in the water balance determined by soil profile characteristics.
DaisyGIS is already an important tool for aiding decision
makers and this study has shown how remote sensing based LAI estimates
may be a valuable tool for model parameterisation and potentially
for model validation. | | >> download as pdf |
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