It is less costly to prevent the phenomena of desertification
from taking place than to solve the problems it causes. Once the damage
has been done, it has to be repaired, which is a long and costly process.
Despite the severity of land
degradation, it is not necessarily the final stage. By employing good
agricultural practice, the trend can be reversed. To preserve soil productivity,
sustainable long-term practices must be applied.
As the population grows, and with it the demand for agricultural products, traditional farming systems are gradually abandoned and given way to the introduction of monoculture, accelerating the desertification process still further. As a result, an increasing number of productive lands are under pressure, to the point where they become sterile. Farmers and cattle breeders with little or no income seem to have no alternative but to exploit new marginal lands.
It is important to respect the capacity charge for each plot of land. This implies assuring the maximum production of a given resource on the land while preserving its long-term capacity to produce. If the capacity charge is exceeded, productivity declines (agricultural output falls, livestock require more time to fatten). Production methods must therefore be modified by prohibiting cultivation during a certain time period (fallow period) or by decreasing the time livestock spend grazing on the land.
5. Senegal: diversifying agricultural production better employs
land resources and prevents over production of a sole product.
In the drylands and oases, man has had to devise clever ways
to exploit the fragile natural resources in a sustainable way.
© Yann Arthus-Bertrand / Earth from Above / UNESCO
Diversifying crop and animal production enables better use of land resources
and prevents the over-production of a single product. A plot can sustain
different plants and animals over long periods, since their nutritional
needs vary and the resources they remove from the land are complementary.
reduces the loss of agricultural products in the case of a natural catastrophe:
certain production methods are better adapted to counter drought than others.
Each plant species has specific nutritional needs (for example, maize rapidly exhausts the soil compared to other plants). Prolonged monoculture should also be avoided on the same plot of land and a system of rotational crop production should be established to restore soil fertility.
Land degradation is not permanent. To restore degraded lands, crop techniques
should be improved by: stabilizing the soil while enriching them with organic
matter, selecting and associating different crop varieties as in polyculture
and reducing land pressure (labour and irrigation)
(See the case studies from Spain and the Aral
Sea). The slightest water table or source can be used to irrigate small
perimeters that diversify food sources and reduces pressure on non-irrigated
lands. It is also important to combat marked soil salinity
by employing the most effective system of irrigation: evacuate water surplus,
monitor the changes in groundwater
reserves (with a piezometer)
and soil salinity in the problem areas, drain and irrigate and plant trees
whose roots hamper the soil from drifting. Moreover, trees act as a windbreak
and provide supplementary resources (wood, leaves and fruit).
Governments and NGOs can facilitate these activities by offering training courses on the use of new technologies adapted to drought. They can also contribute by reducing inappropriate and ill-adapted exploitation techniques and by promoting community land management.
It is not easy to convince local farmers to adopt the idea of giving land
time in which to recover, while reducing herd numbers. However, improving
cropping techniques in cultivated areas may release land for cattle rearing
therefore possibly reducing pastoral pressure and the degradation that results
from it. In many countries, the size of the herd is a source of pride and
honour for the herder, his family or clan (See
cartoon: The School Where the Magic Tree Grows). Education and public
awareness can contribute to spreading another message, which is otherwise
difficult to grasp: by producing livestock of better quality (and improving
veterinary services), the herder’s income can be maintained or increased
despite the drop in herd numbers. Governments should intervene to resolve
conflicts that may occur because of this.
On a political level, regional, national and international measures should regulate market flows (the importation of cheap meat hampers the sale of local meat).
Dig a large deep hole in the school garden to make a compost heap. Everyone can throw in fruit and vegetable leftovers, dead plants and animal droppings, which should be turned over occasionally. (See cartoon: The School Where the Magic Tree Grows).
Be careful not to add animal bones or milk, as it may get very smelly!
Create a nursery in the garden of your school.
Draw the plans, select the appropriate plants, and use the compost and the windbreak (See cartoon: The School Where the Magic Tree Grows).
Write a letter to the President or the Agricultural Minister of your country telling him /her the reasons behind the creation of the nursery.
Why not ask them, through their Ministries or NGOs who are undertaking work in this field, for financial help to buy young shoots and tools to get started
Underline the following correct phrases:
• The practice of polyculture is favoured over monoculture, which exhausts the soil.
• The charge capacity of land is equal to the maximum amount
of crops that can be harvested.
• Every species of plant has the same nutritional needs.
• Land degradation is definite and irreversible.
• It is better to have fewer well-fed animals than a hungry herd.