Abstract
Studying the rill link characteristics and statistical laws of geomorphology of rill networks in fields is essential to clarify the effect of rill networks upon sediment yield from fields with rill networks and to construct a model for predicting the sediment yield. We investigated the rill link characteristics of study rill networks developed in sloping fields using the concept of link for drainage network. Furthermore, we investigated the relationships between the total rill link length, the rill link slope and link magnitude on the basis of link magnitude theories. We obtained several fi ndings:(1) The exterior and interior rill link lengths had gamma distributions, and the slope lengths of the source basins were nearly uniform for half the study rill networks.(2) The link magnitude theories were useful in predicting the number of rill links of any link magnitude within each of the study rill networks.(3) The average of the total link lengths within sub-basins whose outlets are at the upper ends of rill links with magnitude was accurately predicted by linear functions of magnitude for each study rill network.(4) The average gradient of rill links with magnitude was approximated by an elementary function of magnitude for some of the study rill networks.
