Geoscience Reference
In-Depth Information
about the same speed but with gale force gusts of 44 mph on March 18th and 20th.
“The results of this combination of weather conditions were quite spectacular”; virtu-
ally every field that had been finely cultivated for growing sugar-beet around Holme
and Ramsey St. Mary was on the move. Particles of black peat soil were visible up
to a height of 60 m, and where the wind was channelled by buildings or shelter belts,
visibility was reduced to 10-20 m. Apart from the direct loss of precious topsoil, often
with seeds and fertilizer, there was also the cost of digging out blocked ditches which
amounted altogether to £100 per hectare, according to local estimates.
The measures that can be taken to prevent or minimize erosion are mainly good
husbandry with some help from modern technology. Conspicuous losses due to wind
erosion, such as those described above, have led to a variety of cultural practices for
stabilizing the soil surface and reducing wind speeds at ground level. Where the peat
has already worn thin, deep ploughing can bring up clay which, like marling, is most
effective in holding down the soil. Elsewhere nurse crops, such as spring barley, can
be sown, or lines of straw planted at right angles to the prevailing wind, to provide
temporary wind resistance and shelter. The nurse crop is later removed with a se-
lective herbicide such as 'Fusillade' (fluazifop-p-butyl), a light dose sometimes being
first used to check its growth before a second dose administers the
coup de grace.
In sandy districts, the simplest technique consists of cultivating during wet con-
ditions to create a rough, cloddy surface, into which the crop is drilled. Nowadays, a
crenelated surface can be produced with a 'furrow press' plough, the sugar beet be-
ing sown across the grain. A synthetic latex resin, such as vinyl acetate, is sometimes
sprayed on the surface in bands to protect high quality crops. This technique was used
in the early 1960s to stabilize sand dunes on the Norfolk coast, after they had been
breached by storms. The emulsion bound the sand together until marram grass had
grown through again. The agricultural uses have been developed at the Glead-thorpe
Experimental Husbandry Farm in Nottinghamshire.
O
RGANIC FARMING
It is not possible in this topic to do justice to the topic of organic farming but it de-
serves mention as it has a strong following and implications for soils. Modern intens-
ive agriculture now needs great inputs of nutrients to sustain soil productivity, and an
elaborate spraying programme for weed, pest and disease control to realize it. Pro-
ponents of biological husbandry believe that such high technology agriculture cannot
be maintained indefinitely nor, indeed, is it always appropriate. They consider that
much more use could be made of natural biological processes that are neglected in
conventional modern farming. The controversy has run for at least 25 years, and it
is interesting to compare the changes that have occurred within the movement since
