The difference in erosion rates between the organic and conventional
farms was most probably due to their different crop
rotation systems. Only the organic farm included a green manure
legume crop in the third year of rotation, and it had fewer tillage
operations. Comparisons of erosion rates for monoculture plots
or non-legume-based crop rotation plots (typical of many conventional
farming systems) versus legume-based crop rotation
plots (typical of organic farming systems) have indicated a
significant reduction in soil erosion due to legume-based crop
rotations 23-25• The benefits from green-manuring with a legume
crop and reducing tillage operations could be included in the
conventional farming system as well as a reduced level of commercial
fertilizers. If conventional farming methods are not
modified, the loss of valuable Naff topsoil will continue.