AGRICULTURE AND WATER CONSUMPTION.
I read with great interest and shared on my social networks, because I
agree with most, an article in the November 24 appeared in the French newspaper
La Croix, on the division of water.
At the beginning of the article, a first question is asked, important
and I join verbatim, on the main uses of water in France.
"What
are the uses of water?
Three groups of actors draw water
into the natural environment, communities to supply drinking water to homes,
the nuclear industry to cool power plants, and farmers in irrigated areas. The
first two uses are almost neutral in the natural environment. Indeed, the water
used by homes or by power plants is discharged into rivers after use and
depollution. It is quite different for agricultural use: irrigation water is
completely "consumed" by the plant. In net consumption, farmers draw
50% of the volumes, a proportion that reaches 70% during the summer months.”
I want to make a comment about it. The article clearly states that
domestic and industrial uses are neutral to the natural environment, but not
agricultural use.
I do not agree with this view.
Water consumption does not exist. The water does not disappear. The
amount of water available on Earth is virtually the same today than it was a
thousand years ago.
The water is not consumed, it is used for drinking, washing, for
irrigation, for the needs of industry, for the energy production, to make gas
(oxygen and hydrogen), for dissolve all sorts of things.
Agriculture uses water for basic needs of plants and animals, but does
not consume it.
Plants use water for their physiological needs, then reject it, either
as evaporation or within the food product.
Water in excess reaches the water tables feeding them, or water courses
participating maintain a sufficient level, even in summer.
The evaporated water joins the atmosphere as water vapor, feeding the air
humidity and clouds, thus precipitation.
Water "exported" in food, ends up being consumed to be, as it
says in the article, "discharged
into rivers after use and depollution."
In short, this water is not consumed, it changes state. It is very
different.
Water resources may change locally, but not globally.
Yet there is a form of water consumption. But here we only talk about
fresh water and drinking water. Because the problem is there. Here we talk
about something else. Terrestrial living organisms need, in their vast
majority, freshwater and drinking.
But
let's be clear, without fresh water, there cannot be any food production. In
other words, we cannot produce food without water. Agriculture is, and will
always be a freshwater demanding activity.
However, it would be wrong to deny the problem of water waste in
agriculture. This is due to poor management of water available at a given time
and a given place.
Indeed, agriculture needs fresh water, not necessarily drinking, but
soft. Drinking water is especially necessary in the washing of the harvested
product, before its marketing process, in order not to risk contaminating it,
with unfit for human consumption water. In areas where fresh water is scarce,
there may be competition in the use of the available water between the vital
human needs (drinking), household (washing, bathing, watering gardens),
industrial, energy and agriculture needs.
Here we enter a much more delicate zone, politics. Because the division
of water is primarily a political problem. What are the activities that a given
territorial community wants to focus on? At what point in local politics the
debate intervenes? Are there secret interests?
Water is a political weapon, and even geopolitical. Some countries know
this very well, when they built large dams on rivers that provide water to
other neighboring countries, located downstream. Today, in developed countries,
water is an important object of attention, and it is a powerful means of
political pressure.
Whatever the political pressure, a local community must know how to
balance the economic activities it accommodates.
Why
must agriculture save water? Primarily to balance water availability across all
uses. Agriculture is the largest consumer of fresh water in the world, and it's
because it must make a special effort in this direction.
And here, there are several considerations that come into play.
- To save water in agriculture, it is necessary to have efficient
irrigation systems. All these systems require energy, and a heavy investment in
irrigation infrastructure. Everyone cannot afford to make this investment.
- Infrastructure investments must be accompanied by energy investments.
The water pumps for irrigation do not run alone. Therefore, an electrical
availability is needed, with necessary production and distribution networks, or
heat engines, greedy and pollutants.
- Lots of areas or regions, have a water policy which does not encourage
the farmer to make this investment. Only the water pricing by used volume will
be motivating, because farmers will be encouraged to make the necessary
investments in order to lower the water bill. Billing per hectare is still very
(too much) prevalent, that is a fixed payment regardless of actual consumption.
- Traditional flood irrigation has the disadvantage of its high water
consumption, but it keeps some ecosystems assets, around the water courses fed
by water in excess. The reduction in water consumption can have very serious
consequences for the survival of local plant and animal species.
- Reducing the amount of water used in agriculture also requires the
creation of training networks, advice and monitoring, because it requires a
significant technical change in the farms.
Outflow of a coton plot, with flood irrigation
In short, the irrigation management in order to save fresh water is not
neutral, nor on the cost of food, nor on the environmental impact of caused
changes.
Agriculture
has not only an indisputable role in food production, it also has a major role
in maintaining ecosystems.
All
reforms on agricultural production methods, systematically affect, not always
in a well measured level, the surrounding ecosystems.
Many people tend to look at agriculture, primarily as a major source of
pollution. It has been true, it is much less today. Not all is perfect, far
from it. But beware of hasty political decisions without in-depth studies of
the potential impacts at all levels, particularly in relation to water.
Never
forget that without water, there cannot be agricultural production, so no food
production.
Eat and drink will always
remain the first basic needs of all living beings.
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