importance of soil for life on the planet and soil security

2. Why aren’t we talking about soils
and soil security?
Bijay Singh
Punjab Agricultural University
Ludhiana

3. Simple definition of environment
• Permeable membrane that shapes life into the
form in which it exists, with an inherent
capacity and resilience to function and
respond to stimuli
• The Earth’s permeable membrane or skin of
soil, water and air is the environment of man
and all living things.

4. Soil in the man’s environment
• It is the environment that provides water, oxygen,
food and shelter; the necessities of life to man and
all living beings.
• The three interacting phases of the environment - -
solid, liquid and gases driven by energy from the
sun give rise to soil and terrestrial life as we know it

5. Soil in the man’s environment
Conceptual diagram of the physical environment

6. • It is in the holistic sense that life on earth is
dependent on soil.
• The soil is the environmental integrator as it is
the terrestrial reactor of the planet and
exchanger of minerals, air, water and energy.
• Soil is the earth’s fragile skin that anchors all
life on Earth. It is comprised of countless
species that create a dynamic and complex
ecosystem and is among the most precious
resources to humans.
Soil in the man’s environment

8. ‘Man, despite his artistic pretensions, his sophistication, and his many accomplishments,
owes his existence to a 15 cm layer of topsoil and the fact that it rains.’
‘A soil is an entity – an object in nature which has characteristics that
distinguish it from all other objects in nature’
“Essentially, all life depends upon the soil ... There can be no life
without soil and no soil without life; they have evolved together.”
Soil provides us grains for our food, cotton for our clothes and timber
for our homes. It is one of the most important resources for mankind
The affairs of the soil touch our daily lives most intimately.
“Upon this handful of soil our survival depends. Husband it and it will
grow our food, our fuel, and our shelter and surround us with beauty.
Abuse it and the soil will collapse and die, taking humanity with it”

9. Make distinction between LAND and SOIL
in our language and policies
• For many people the word ‘soil’ is
interchangeable with the word ‘land’. This lack of
distinction in terminology results in an oversight
of the underpinning role of soil within
landscapes.
• Soil is a distinct living entity that is one of the
core building blocks of land. Land consists of
soils, rocks, rivers and vegetation (Lal, 2010).

10. Soil contributes five principal
functions within a landscape
1. Nutrient cycling
2. Water retention
3. Biodiversity and habitat
4. Storing, filtering, buffering and
transforming compounds and
5. Provision of physical stability and support

11. SOIL IS A LIFE SUSTAINING NATURAL RESOURCE
• Everything that lives on the earth depends on
soil. More than 99.7 percent of human food
(calories) comes from the terrestrial environment
(FAO Food Balance Sheet)
• We have a limited supply of fertile soils. Of the
total of 13 B ha of land area on Earth, cropland
accounts for 11%.
• We not only need to conserve and protect our
soils but also ensure that these remain healthy

12. It takes about 500 years for
1 inch of topsoil to form.
Soils are not merely an
accumulation of debris
resulting from decay of rock
and organic materials ..
These are developed as
rocks are weathered and
covered with organic
materials

13. Soil erosion by water, wind and tillage
affects both agriculture and the
natural environment. Soil loss, and its
associated impacts, is one of the most
important (yet probably the least well-
known) of today's environmental
problems (BBC 2000; Guardian 2004).

14. • The effects of soil erosion go beyond the loss of
fertile land.
• It has led to increased pollution and
sedimentation in streams and rivers, clogging
these waterways and causing declines in fish and
other species.
• And degraded lands are also often less able to
hold onto water, which can worsen flooding.
• Sustainable land use can help to reduce the
impacts of agriculture and livestock, preventing
soil degradation and erosion and the loss of
valuable land to desertification.

16. • Half of the topsoil on the planet has been lost
in the last 150 years.
• In addition to erosion, soil health is affected
by other aspects of agriculture.
• These impacts include compaction, loss of soil
structure, nutrient degradation, and soil
salinity. These are very real and at times
severe issues.

18. Healthy Soil: The Foundation of Life
• The birth right of all living things is health
• It is equally true for SOIL, plant, animal and
humans, and the health of these four is a one
connected chain.
• Healthy soil makes healthy crops, healthy
people and a healthy society
Albert Howard (1940)

19. Defining Soil health
• An integrative property reflecting the capacity of soil to
respond to agricultural intervention, so that it continues
to support both the agricultural production and the
provision of other ecosystem services.
• A healthy agricultural soil is one that is capable of
supporting the production of food and fibre, to a level
and with a quality sufficient to meet human
requirements, together with continued delivery of
other ecosystem services that are essential for
maintenance of the quality of life for humans and the
conservation of biodiversity

21. Why recent emphasis on soil health?
• Soil management is fundamental to all agricultural
systems
• There is evidence for generally slow but
widespread degradation of agricultural soils - - as
erosion, loss of organic matter, nutrient imbalance,
contamination, compaction, increased salinity and
other harms
• Thus, in recent years research is being directed to
devise measures of the health of soil and inform its
management so that degradation is avoided

22. The key to good soil health is
Soil Organic Matter (SOM)
• Organic C transformations, soil structure maintenance,
nutrient cycling and biological population regulation – all
controlled or influenced by SOM
• Two crucial characteristics of a healthy soil are the rich
diversity of its biota and the high content of SOM
• SOM influences numbers, kinds and diversity of
organisms in the soil as it is their basic energy source
• If the SOM is increased or maintained at a satisfactory
level for productive crop growth, it can reasonably be
assumed that a soil is healthy

24. Conservation Agriculture systems – the three
key elements
• No or minimal mechanical soil disturbance,
• Permanent organic soil cover specially by crop
residues and
• Cover crops, and diversified crop rotations in
the case of annual crops or crop associations
in case of perennial crops, including legumes.

25. Fertilizers improve soil health if
• These are applied to supply to the plants
adequate amount of nutrients and in a
balanced proportion
• Their long-term use does not lead to reduced
soil organic matter levels
• Their application does not lead to generation
of excessive acidity in the soil
• Application of N fertilizers does not lead to
large N deposition

26. SOIL SECURITY
Maintenance and improvement of the
world’s soil resources so that they can
continue to provide food, fibre and fresh
water, make major contributions to energy
and climate sustainability, and help
maintain biodiversity and the overall
protection of ecosystem goods and services
(Koch et al., 2012).

27. Soil Security
• History stands as a warning to our modern
societies. Whole civilizations have fallen and
collapsed when their stock of fertile soils washed
or blew away.
• Many clarion calls to preserve our soil stocks
have been made; we can no more afford to
ignore these

28. “Upon this handful of soil our survival depends.
Husband it and it will grow our food, our fuel,
and our shelter and surround us with beauty.
Abuse it and the soil will collapse and die, taking
humanity with it”
Atharava Veda, the Sanskrit Scripture, 1500 BC
It is the farming inefficiency arising from deterioration of soil health
due to misuse of soil, which is at the root of non-sustainable
agriculture and associated degradation of environment.

30. Resolution adopted by the UN General Assembly on
20 December 2013 to designate 5 December as World
Soil Day and to declare 2015 the International Year of
Soils
The sustainability of soils is key to addressing the
pressures of a growing population and that
recognition, advocacy and support for promoting
sustainable management of soils can contribute
to healthy soils and thus to food-secure world and
to stable and sustainably used ecosystems

31. "The multiple roles of soils often go
unnoticed. Soils don’t have a voice,
and few people speak out for
them. They are our silent ally in
food production."