366 Ecological Restoration and Design
Biomass
A constraint that can be critical for many of these biologically driven innovations
is the availability of biomass for keeping soil energy and nutrient stocks sufficient
to support higher levels of biological activity. The use of fast-growing leguminous
trees and cover crops presents varied opportunities for increasing biomass and also
enhancing N supplies in the soil. Finding ways and means to grow more abundant
biomass on presently uncultivated land, with techniques that are environmentally
benign and labour-efficient, is one of the most important areas for research in sup-
port of various biologically driven approaches. Complementing this are the pro-
duction and use of bioproducts such as compost and inoculants that enhance the
productivity of organic and other inputs.
As noted above, little thought and little investment have been devoted to
reducing biomass production as a constraint. As long as the returns to making
organic inputs are moderate to low, there is little incentive for researchers or farm-
ers to tackle this problem. But the kind of productivity and profitability gains that
are documented in Uphoff et al (2006) should make this an attractive area for
experimentation, including the design and production of tools and transport
equipment that can enhance labour productivity. The work of CIRAD and its
partners in Brazil and Madagascar has shown, for instance, that there are some
plants that can grow very well in dry or cold seasons and have aggressive rooting
systems that improve soil structure. These can produce large amounts of biomass
when there are no crops being grown. This means that there is little or no oppor-
tunity cost in terms of agricultural output and, instead, a substantial augmentation
of production when these plants are utilized to increase soil organic matter and
improve physical characteristics.
Further, as noted above, inorganic nutrients can often be productively used to
increase biomass output. No opposition or mutual exclusion between organic and
inorganic inputs should be erected that leads to a suboptimization that is not in the
interest of farmers or of sustainable soil systems. Soil and climatic constraints have
been the major physical limitations on agricultural production in the past. Inorganic
inputs that help to increase organic outputs can diminish both constraints. By creat-
ing better soil conditions and root systems, they can even offset some of the con-
straints of rainfall and temperature by holding water and buffering heat or cold.
The production of compost on a commercial basis, and especially of vermi-
compost, is expanding in India and other countries. The production of biofertiliz-
ers and agents for biological control of pests and diseases is being taken down to
the village level, so that employment is created at the same time that farmers using
these bioproducts get higher output and profits. Unlike the production of bio-
mass, manufacturing these products does not require any access to land. The same
is true for production of bacterial or fungal inoculants, which have the effect of
‘producing more land’ by raising the productivity of existing cultivated area. These
are innovations well suited for the 21st century. Biologically based agriculture will,
it appears, be increasingly integrated into commercial production activities at both
large and small scale as part of future agriculture.