Hi,
I am having problems to understand for what exactly the aspect threshold stands for in the RUSLE modul.
First of all, why is the aspect important and influencing soil erosion?
Secondly, since the aspect describes the direction of slope it can have any value from 0.1-360° but how do I determine a threshold value, if my area is having slopes extending in various directions?
Thanks.
Briefly, as stated in the Help system, the slope and aspect thresholds are used for partitioning the topographic surface into homogeneous patches. Since the number of patches has a limitation of 32,000, the threshold for slope and aspect should be chosen carefully. If they are given too small, the number of patches might be greater than 32,000, which is not allowed.
Please refer to the TerrSet Help system and the references listed at the end of the RUSLE help section for more information.
Best,
Clark Labs
Well, it is more the aspect that is unclear for me. Especially since the aspect threshold is not mentioned in any of the references.