Soil surface roughness modelling with the bidirectional autocorrelation function

Surface roughness is a major part of soil surface condition. It results from tillage operations and weathering. parameterisation still scientific lock the object many studies. An efficient parametrisation by modelling bidirectional autocorrelation function estimated 2.5D digital elevation models surfaces introduced. not only provides geostatistical parameters that can be related to other characteristics, but let us emphasise it reproduces with very good accuracy. The often modelled three parameters, height variance, single correlation length, exponent. We added two in order take into account anisotropy align coordinate system direction maximum length. propose way estimate show its robustness for using laboratory tests repeated rainfall events. One evolves isotropy anisotropy, undergoes reduction initial anisotropy. improvement brought second length thus highlighted. Under impact, variation lengths more marked than usual parameter root mean squared heights. Both are complementary, capturing horizontal or vertical respectively. evolution exponent showed slight increasing trend, which smoothing.