Famous scholars from Kiel:
Eilhard Alfred Mitscherlich
Throughout the world researchers today still use the "Mitscherlich containers" to investigate nutrient absorption by plants. The career of the agricultural scientist started at Kiel University.
He probably could not follow any career other than that of a scientist: the agricultural scientist and soil scientist Eilhard Alfred Mitscherlich, who was born in Berlin in 1874, grew up as the son of a well-known academic family partly in Berlin and partly on the estates in the Kurmark and Lower Silesia, which belonged to his maternal grandfather. His other grandfather was Professor of Chemistry and Mineralogy, his father was Professor of Surgery. Mitscherlich later made a name for himself worldwide because he substantially expanded the knowledge about growth and crop yields to a large extent.
However, initially Mitscherlich began to study physics in Kiel in 1895. After only one term he changed subject. He had found his true vocation: agriculture. In 1898 he was awarded his doctorate on „The evaluation of the physical properties of the soil by means of the heat of wetting". Later he worked as a scientific assistant to Hermann Rodewald, the head of the Agricultural Institute of Kiel University at that time which was still then located on Niemannsweg. In 1901 Mitscherlich was promoted to professor and received the Liebig award for his "Investigations on the physical properties of soil" from the Bavarian Academy. He remained a private lecturer until 1906 at the Agricultural Institute and that year moved to become full professor at the University of Königsberg.
Professor Hans-Peter Blume from the Agricultural Sciences Faculty is holding one of Mitscherlich’s most important achievements in his hands, which was already completed in Kiel. It is the textbook "Soil science for agriculture and forestry". It has been used on academic courses for decades. On one of the first few pages the dedication to Mitscherlich’s »revered teacher Hermann Rodewald« stands out. When this edition was published, Mitscherlich himself had already been in Königsberg for a long time, »but obviously still felt attached to his old university and the Professor«, says Blume.
Mitscherlich was one of the first researchers, who recognised that the physical-chemical properties of the soil were particularly important for growing crops. He studied the nutrition of these plants in laboratory trials and incorporated his findings on increasing yields in 1909 in a mathematical formula, the "Effect law of growth factors". This was received with interest throughout the world and became the basis for new questions and research.
Mitscherlich was a founder member of the International Soil Association established in 1924 and was Chairman of the „Committee for soil fertility and plant nutrition“ for many years. Later he became an honorary member and was already so renowned in 1946 that the Soviet army of occupation „rather exaggeratedly, brought him to Berlin in a saloon car”, reports Blume. There in the former DDR, Mitscherlich became full Professor for Agricultural Engineering at the Agricultural-Horticultural Faculty of the Humboldt University in Berlin. Four years later he started work as Director of the Institute to Increase Crop Yields at the German Academy for Sciences in Berlin, to which he devoted himself until his death in 1956. Mitscherlich was greatly revered for his achievements, several universities awarded him honorary doctorates, including the CAU. Since 1964 Gießen University has awarded a prize to agricultural scientists bearing his name.
Jana E. Seidel
Pots with a double bottom
Image: pur.pur © Kiel University
Eilhard Alfred Mitscherlich invented special plant containers for manure trials. The so-called "Mitscherlich containers" have a double bottom, into which excess liquid fertiliser flows. This means that the amount of nutrients provided to the plants can be measured accurately. »Manure is added to up to ten kilos of soil in the containers in the manner prescribed in order to be able to find out how much nutrient wheat or potatoes for example absorb«, explains Professor Hans-Peter Blume from the Institute for Plant Nutrition and Soil Science.
The "Effect law of the growth factors", which was first published in 1909, is probably Mitscherlich’s most significant contribution to research. Before him Carl Sprengel and Justus von Liebig had assumed in their "Minimum law" that amongst all the nutrients the one that has a decisive factor on the growth of a plant is the one which is available in the smallest quantity. However, Mitscherlich proved that the yield is dependent on every individual nutrient and it can be increased by intensifying each one individually.