<<MY QUESTION IS -- If you wanted a scientist to quantitatively test some
hypothesis about permaculture, what exactly would it be?!
Paul Cereghino, Olympia, WA -- card carrying M.S.
I would recommend the book "Agroforestry for Soil Management" by Anthony
Young to anyone interested in permaculture. He formulates many hypothesis
relevant to Agroforestry. e.g. Trees prevent soil erosion and increase water
infiltration; Trees cycle back nutrients that would be lost otherwise in
runoff; nitrogen-fixing trees can supply enough nitrogen to support to
growth of other crop plants, etc, etc. Young's research shows that many of
the hypotheses are correct under certain conditions, and for some the
experimental data so far is inconclusive. Leucana for example, may not be
suitable for alley cropping in arid climates, because it can compete with
crops for water. Even though it helps to increase water infiltration into
the soil, the net effect can be negative in some situations. A lot of
scientific work has been done by ICRAF in Africa and in other countries to
validate agroforestry methods under different conditions. Unfortunately, a
lot of this is difficult to implement because of economic considerations,
e.g. extra labour required to plant and maintain hedgerows, etc.