Why soil matters?

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12 Why soils matters - A european perspective
soil organisms and partially decomposed plant and animal
residues.
Besides, Dr. Watson highlighted that there is clearly a
climate impact on the capacity of soil to store carbon.
Globally, twice as much carbon is stored in soils as is
present in the atmosphere. This is both a threat and an
opportunity. The threat is land use change. The opportu-
nity is She also noted that organic matter
turns at a slower rate when it is wet and cold.
Dr Watson reminded us that the world’s cultivated soils
have lost 50 to 70 percent of their original carbon stock.
Nearly 50% of European soils contain very low levels
of organic matter (0-2%), which have been caused by
agricultural intensification. (Quinton, J., et al. Soils and
food security briefing. (2012)).
Soil is home to a quarter of our planet’s biodiversity,
which is essential for food security and nutrition.
A single gram of soil may contain millions of individual
bacteria,belonging to several thousand different species.
In other terms, soil is alive and it is the diversity of soil
organisms that is the engine keeping it alive.
Given such amazing diversity, we do not k
of all microorganisms in the soil. Now, th
of science is to identify what is in the s
the role of these microorganisms in the soil, to be able
to manage it. The example of the tardigrade, more com-
monly known as the water bear, illustrates exactly this situ-
ation: it is omnipresent in the soil, found in all geographical
areas and able to resist extreme weather conditions, but
science has not yet discovered the exact role of this micro-
organism.
There are many ways to manipulate what happens in the
soil through different management practices, whether it
be monoculture, drainage, crop diversity, crop rotation,
tillage, agrochemicals, fertilisers and manure - all of these
practices are key factors in determining what happens in
the soil, for soil biodiversity and soil carbon levels. This is
why it is important to understand more about how all these
management practices interact to give us what we need.
Dr Watson detailed the
, based on a recent study, and explained that
monoculture (e.g a continuous culture of maize) maintains
a baseline level of soil carbon, while, with rotation of 2
crops, there is already an increase in soil carbon of 3.6%
and an increase in nitrogen in the soil of 5.3%. Eventually,
with crop rotation management combined with cover
crops we can improve soil carbon by 8.5%. Crop rota-
tion also increases the soil microbial biomass by 20.7%.
Therefore, soil has the ability to store carbon, but this
ability depends on its texture. This texture can be im-
proved via certain agricultural management practic-
es. Evidence shows that techniques based on mimicking
nature contribute to more carbon storage in the soil.
Dr Watson also drew our attention to the challenges
ecurity. These challenges
s to soil protection and
are also related to better
use of food waste and sewage in urban as well as rural
areas. Precision technologies, which aim to use material
more efficiently, should also be explored. Eventually, our
ability to make dietary choices and adapt to changes
is key to surmounting these challenges.
Proceedings of the Conference