Significant changes are occurring in European agriculture today. They relate to agricultural exports and agricultural structures, agricultural and livestock farming systems and production technologies. They have a profound and certainly irreversible impact on the entire sector. They do not have the only incentive in seeking maximum profit, but come more deeply from the coordinated policy of state bodies, namely because of the desire to provide the population with a plentiful and varied supply of food at the best possible price while protecting the ratio of agricultural income to other professions.
These two goals in foreign agricultural service cannot be achieved simultaneously without the optimal development of soil and labor and the intensification of production processes. If these technological changes are both inevitable and justified at the socio-economic level, the fact remains that they can affect the quality of the environment and its resources in the short, medium and long term. Since they cover large areas of agricultural space, they also give this problem an exceptional dimension.
Therefore, it is important to ask questions about the agricultural trade account and analyze the facts and mechanisms involved in long-term thinking. This need becomes even more urgent, as the mutations of modern agriculture occur at a time when modern society assigns new and multiple functions to campaigns, namely the hydrological function (conservation of aquifer resources), biological function (conservation). wildlife), the living function (primary and secondary residences) and even the recreational function (outdoor activities) and cultural (protecting peasant crops), which are now added to the main production function and require more integrated concepts for the use of rural space.
Significant changes affect agriculture supplies and traditional farming systems today. In fact, we are witnessing the specialization of farms, which combines agriculture and livestock. In large grain and sugar beet farms that operate without livestock, conventional crop rotations with fodder and green manure and the use of farm manure cease. Consequently, cultural continuities are simplified, leading to standardization of rotation; this process leads to the formation of vast surfaces occupied by the same plant or the same variety, and sometimes to a sequence of the same growth on itself. This is the phenomenon of “monocultures.”
In addition to these modifications of farming systems, it can be seen that agricultural work, from plowing to harvesting, is increasingly carried out on combined or large-sized machines that pull more and more powerful tractors. Transportation of these heavy vehicles on land can lead to compaction of the soil, which will affect its structural qualities and, therefore, its production potential.
Numerous agricultural exports experiments that have used simplified successions, such as beets or cereals, have led to crop loss after several years of crop loss, sometimes due to chemical depletion of the soil, sometimes a deviation from its biological properties (soil fatigue) or physical properties ( structural regression). An analysis of the results, however, leads us to conclude that the main obstacle to simplified successions is the phytopathological (propagation of diseases or pests) and phytosociological (propagation of weeds), the use of agricultural biocides of which allows only temporary control.
The rejection of organic manure and green manure, as well as some practices such as burning straw and stalls, which characterize agriculture without livestock, lead to a decrease in the medium-term content of organic matter in soils. However, it has been found that this content is stabilized in the long run due to roots and plant debris left on the ground. In ideally textured soils (silts), apparently, this decrease in organic matter does not significantly affect the structural quality of the soil even after ten years. Indeed, modern methods of assessing the structural state do not indicate a noticeable deterioration, even when the yield really decreases for other reasons (cryptogamous diseases, competition with weeds). However, sandy and heavy clay soils are a priori apparently more sensitive to a decrease in the amount of organic matter, and more careful monitoring should be carried out in this regard.