[Soil fertility in Latvia in the period 1970-1995 and the prognosis for the nearest future]
1997
Boruks, A. (Latvian State Scientific Research Institute of Agriculture "Agra", Skriveri (Latvia))
The aim of the present research is to clarify soil fertility, its changes in time as well as the tendency of its development in Latvia. The method for expressing soil fertility in crop units per ha of land has been worked out. The annual amount of plant breeding products in the period of 1970-1995 expressed in crop units per year has been calculated. The resulting data have been analysed. The analysis shows that the amount of crop units produced in different years depends on weather conditions, agrotechnical methods, way of management and fertilization
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