The alternative systems of agricultural production that agree with the environment are called on one hand ecological, biological, organic and biodynamical, and on the other one natural.

Terms like ecological, biological, organic agriculture, biodynamic or biological - dynamical define an agrarian system, which main goal is to obtain products with high quality, respecting the environment and preserving the land fertility, by means of the ideal resources utilization and without employment of chemical products of synthesis (Regulatory Council of the Ecological Agriculture, 1990). This way there remains legally definite the agriculture which generic denomination will be ECOLOGICAL.

There exist a series of resultant problems for using chemical fertilizers, like nutrients loss for lixiviation, waters pollution, biological activity reduction in our land, etc. The last point is the main one if we are trying to preserve our lands and produce as much as possible, or what the same thing is: lands alive in good conditions (physical and chemical).

The ecological agriculture offers a logical solution and with scientific foundation, which takes root in the active nourishment of the soil across the supply of organic matter (humus) in his different configurations, without forgetting the mineral contributions in the shape of mineral pulverized rocks. In this way, the main sources for humus that appear in the Regulatory Council of the Ecological Agriculture are:

- Manure separated into its elements (decomposed) by fermentation in heap, in hole or in the surface.
- Residues of crops.
- Green credits.
- Straw and quilted others.
- Compost done from organic residues.
- Humus of worm.