Geoscience Reference
In-Depth Information
had not already caused a return to ploughing, the objections to straw burning would
probably have produced the same result. Straw incorporation is now becoming com-
mon practice, and the implications are being thoroughly studied so that farmers can
adopt the best agronomic measures.
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OSTSCRIPT
The theme of this chapter has been soil productivity for agriculture. It has not con-
sidered the much broader issues of landscape, farm subsidies, nature conservation or
the balancing of national needs. These issues have been variously addressed by oth-
er writers, such as Nan Fairbrother in
New Lives New Landscapes
, Marion Shoard in
The Theft of the Countryside
, and Kenneth Mellanby in
Farming and Wildlife.
Even within the narrower theme of productivity per unit of land, one must re-
member that good soil management and fertility are only part of agronomy; the im-
portant roles of plant breeding and crop protection have not been dealt with. We now
know that high input agriculture can be much more productive than was thought pos-
sible 20 years ago when G.W. Cooke discussed the question of food production in
Britain. Furthermore, fears that the soil structure was being fatally damaged, and its
inherent fertility was being destroyed, have not been fulfilled. In agricultural terms,
the soil structure has actually been improved in many cases, as increased crop yields
have been accompanied by greater crop residues ploughed back.
Of course, these improvements have been bought through increased dependence
on agrochemicals and through the simplification of ecological systems. In concentrat-
ing on production for human consumption, less energy is dispersed through alternat-
ive pathways, and this must be reflected in reduced diversity of plants and animals.
The next chapter considers some of the problems and indirect costs of intensive farm-
ing, including the effects of farming practices on the soil fauna, and the capability of
the microflora for dealing with pesticide residues in the soil. It also reviews the risks
of soil erosion and the pollution of ground water by nitrates.
