Water at the Heart of Science
12
Water
in the Fields
Irrigation
has made man less dependent on unpredictable rainfall to grow crops.
But with the intensification of farming today, care must be taken not to deplete
water resources.
Producing more
Managing sustainably
Saving water
To deal with population growth,
agricultural production needs
to increase, become less
haphazard, remain affordable,
and generate sufficient income
for farmers. This will naturally
imply a growing demand for
irrigation water.
It is therefore important to
promote technologies and
institutional frameworks for
practices that not only use
less water, but are also less
demanding of energy and
farming land. However, it is
important to make sure that
such innovations, which are
often costly, do not generate
social inequalities.
Agronomists are looking at
methods to produce more
crops, less infrequently, with
a given amount of water, for
instance through drip irrigation
or micro-sprinkler. Human and
social sciences are studying the
effectiveness of technological,
economical or institutional
innovations and their costs
and benefits for different
social categories. They are
also analysing the impact that
people’s behaviour, standards
and values have on the future
of innovations, and in return,
how the latter influence social
relationships.
1 Small dams help to store part of
a river’s flow to provide drinking
water for livestock, as well as
water for irrigation and household
use. Dams play a vital part in the
economic and social development
of rural areas.
2
1
4 According to most experts,
the only way to increase farming
production without augmenting the
surface area of irrigated land is to
develop rain-fed crops.
5 The drip irrigation and the microsprinkler are characterized by the
application of small quantities of
water as directly as possible to the
plant root.
2 Only 18% of all farmlands in the
world are irrigated, but alone they
represent half of the water supply
destined for human use.
6 Drip irrigation, if well controlled,
enables to save 10 to 20% of water
compared to sprinkling and 40
to 60% compared to irrigation
in furrows for the same output
objective.
3 In many semi-arid regions,
irrigation is challenged by shrinking
groundwater levels, rivers running
dry, and dams that are filled
insufficiently. A dry El Haouareb
dam in the Merguellil valley in
Tunisia.
4
5
3
6
Water at the Heart of Science
13
A Tricky
Equation
Morocco’s Saiss basin
is an important farming region. For the past thirty years, wells and drill holes have given
access to groundwater and encouraged farmers to irrigate their crops, in particular vegetables
and fruits.
In the Saiss basin, where
rivers are scarce, individual
access to groundwater
has supported the rapid
development of agriculture and
improved the lives of thousands
of farmers. Such activities
quickly led to the overuse of
groundwater. Scientists are
now looking at economically,
environmentally and socially
sustainable solutions to irrigate
crops in the region without
using up the water table.
Researchers have
demonstrated that access to
groundwater in the Saiss basin
is far from common. Nearly
50% of all farmers are deprived
of it for technical (shrinking
water table), economic (cost
of making a drill hole) or
institutional reasons (conditions
that restrict access). In
addition to the environmental
issues (overuse of groundwater,
intensive use of fertilisers
and pesticides), some farmers
are therefore also becoming
marginalised.
The ARENA project (SIRMA network)
implemented in Morocco, Algeria and Tunisia
includes research and higher education
institutes for agronomics in the Maghreb
(INA of Alger, IAV Hassan II in Rabat, ENA in
Meknes, INA of Tunis and INRGREF of Tunis),
as well as French research institutes: Irstea,
Cirad and IRD.
Scientists have been
studying these matters, and
recommend participative
methods to build development
scenarios. All stakeholders must
be involved in discussing ways
to ensure the economically,
environmentally and socially
sustainable development of
irrigated farming and manage
the water resources on which
it depends.
Saiss basin
1 Fruit and vegetables for the
national market make up the
majority of farming produce in
the Saiss. These are all dependent
on irrigation, and drop-irrigation
systems are widely used.
4 Since 2000, the level of
groundwater in the Saiss aquifer
has been decreasing by an average
1m each year. Drilling sometimes
has to go deeper than 120m before
it hits water.
2 Saiss is known for its onions,
here lying in wait for higher market
prices.
5 Farmers in a participative
workshop discuss changes in
their production systems and the
implications for irrigation needs
in the Mitidja plain (Algeria).
Workshops of this kind are now also
held in Morocco’s Saiss region.
3 Only farmers who have regular
and sufficient access to water are
able to find a place in the high
value-added sectors (milk, fruit and
vegetables).
6 Pipe for a drip irrigation system.
Though it saves water and helps
to increase productivity, drop
irrigation requires considerable
investment.
3
4
1
2
5
6
Water at the Heart of Science
14