soil.mep
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SUSTAINABLE SOIL MANAGEMENT
because of continued progress in cropping systems. However, the trend towards reduced fertilizer use in European agriculture needs to be monitored closely, since in the longer term, nutrient deficiencies may affect the health and quality of crops as soils become exhausted.
On mined or abandoned areas, where there is often less plant cover and, as a result, less protection for the surface of the soil, soil fertility and soil structure may suffer further. Soil degradation and erosion problems could increase, especially in those southern European regions where it is less easy to achieve plant cover to protect the soil.
Using advanced techniques such as fertigation Drip irrigation, a technique that provides crops with water through special pipes at a high frequency but with a low volume of water (drips), can be combined with fertilizer a p p l i c a t i o n , t o o ff e r f e r t i g a t i o n . I t i s a t e c h n i q u e t h a t i s p a r t i c u l a r l y a p p ro p r i a t e i n d r y z o n e s , f o r e x a m p l e i n t h e Mediterranean region. Fertigation enables the farmer to meet the specific water and nutrient needs of the crops with great precision, thus minimising losses of both precious water and nutrients.
A beneficial side effect of fertigation is the avoidance of soil erosion and soil degradation, in that it eliminates the use of heavy machinery that can cause soil compaction. In addition, less water is needed to produce 1 kg of dry matter, since the water supply can be adapted to the speed of infiltration, thereby avoiding surface runoff and erosion. Fertigation allows cover crops or spontaneous vegetation to be grown in between rows of trees, with
positive
e ff e c t s
on
soil
conservation.
M o re o v e r,
this
technique facilitates the growing of trees on slopes, thereby making a further contribution to the prevention of erosion.
▲ Fertigation in Spain (water and nutrients are applied drip-wise through pipes).
In humid regions and areas with high rainfall, farmers work actively to maintain or improve the soil’s ability to ‘digest‘ water. Forming canals and installing drainage pipes to remove surplus
water are common technical solutions in northern Europe. In the dry regions of southern Europe, making use of irrigation and fertigation (i.e. combined irrigation and fertilizer application), improving water storage capacity, and covering the surface of the soil are techniques used to achieve efficient water management.
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