Soil is an intermediate link between alive and lifeless nature and the result of the long-term interaction between them, which is necessary for life to exist on the earth. Soil has to be treated as a natural resource in constant development, where both the mineral and the organic part as well as the soil biota are important. Soil is the only means of production which can improve (i.e. become more fertile) when used correctly. Knowledge about the soil and its connection with the environment is a prerequisite for the use and protection of sustainable natural resources.
As the formation of soil is an extremely slow process and it could take hundreds of years for fertile soil to develop, the soil is regarded as non-renewable natural resource. Of all the land on earth, there is only 1/3 of agricultural fertile land, and only 1/3 of it is formed by the area under cultivation. It would be extremely difficult or even impossible to develop new arable land from the remaining area. In the Estonian Rural Development Programme 2014-2020, the decrease of soil fertility has been mentioned as one of the most significant problem to handle.
In recent decades, catastrophic changes in the use of land have taken place all over the world. The area under cultivation per person is reduced every year due to population increase, desertification, erosion, deflation, incorrect use of land, soil pollution, expansion of cities, mining the mineral resources, etc. The pollution or destruction of soil as the consequence of natural processes or human activity is called degradation.
Soil protection is the application of means to preserve and improve the soul as natural resource and also to restore it in case of damages and to protect the soil from destruction, degradation, and pollution.
Conditionally, soil protection can be divided into three:
- Reduction of the physical destruction of the soil
- Application of measures against the degradation of soil characteristics and the improvement of soil characteristics
- Classical nature protection and protection of nature sciences
From the viewpoint of soil fertility, the main problems in Estonia are the following:
- Lack of organic matter and nutrients in soils
- Leaching of mobile nutrients, which causes the fertility of our soils to reduce
In Estonia, there are favourable conditions for nutrient leaching, because the amount of precipitation exceeds evaporation about 1.5 times. In crop cultivation, the nutrients leach the most in a period where the soil is not covered by crops, i.e. in autumn since harvesting the crops to the land freezing.
Contemporary agricultural production comes hand in hand with environmental sustainability. For the functioning of integrated and environment-friendly agriculture, the minimisation of soil pollution caused by the use of synthetic plant protection products besides the preservation of the reserves of organic matter and nutrients and leaching avoidance.
Humus balance calculator
The balanced humus state of soil receives more and more attention according to agronomical and economical aspects. First and foremost, humus balances depend on the production level, the soil, the cultivated crops, and fertilisation.
A user has to enter the following initial data into the calculator to find out the current state of the humus reserve:
- thickness of humus layer
- organic carbon or humus content
- soil integration