Agriculture Reference
In-Depth Information
soil security. This improved soil management resulted in distinctly differ-
ent phenoforms of the given genoform, associated with different forms of
management. Distinction of phenoforms offers a more specific possibility
to extrapolate management expertise to nonstudied locations with the same
soil type: the classic procedure in land evaluation.
5. Smallholder agriculture has to be considered in a broad societal context,
with a focus to the future. Rockstrom et al. (2009) have defined planetary
boundaries for nine issues, among them land use. Feeding 9 billion people
in 2050 will require a 50% increase of agricultural production. The mar-
ginal character of many smallholders at this time does not allow such an
increase, although case studies reviewed show that significant improve-
ments can be made by improving management practices. Larger production
units, using modern production techniques, are needed and this develop-
ment occurs in the developed world. The two Dutch case studies show the
potential of intermediate sizes of farms, providing satisfactory incomes and
a range of ecosystem services, creating soil security.
ACKNOWLEDGMENT
The authors gratefully acknowledge valuable comments by Dr. K.E. Giller, professor
of plant production systems at Wageningen University, the Netherlands.
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