Mitscherlich is everywhere – mistake or food for thought?

O. Nestroy, Institute for Applied Geosciences at the Graz University of Technology
The previous presentations on the life and work of Professor Max Eilhard Alfred Mitscherlich in the original Russian version and in the German translation provided the proofreader with food for thought to pursue the ingenious findings of E. A. Mitscherlich expressed in mathematical formulas and to project them into current everyday life. In this epilogue, based on this presentation and therefore proceeding from plant physiological parameters, in a further step the validity and topicality of the Mitscherlich law in the everyday life of high-performance societies in industrialized and developing countries will be shown. In the author’s opinion, bridging the gap between the knowledge of E. A. Mitscherlich derived from soil science and plant cultivation and the present is not as difficult as it might first appear. This “border crossing” of a natural law to political economy will be explained using some examples taken from pulsating life. Two passages from the previous presentation should make this easier. First the note that the results of Mitscherlich’s research “have not lost their relevance” to this day, as well as that the law represents a “basic law of life” and “one of the laws of agriculture and ecology, according to which all living systems orientate themselves on different levels of their organization”. These quotations, taken from the above-mentioned essay about E. A. Mitscherlich, were for a closer study of the regularities recognized by Mitscherlich and at the same time an encouragement to trace them using a few examples from today’s everyday life. But first back to the roots and to E. A. Mitscherlich’s “Law of Action of Growth Factors”. E. A. Mitscherlich used the findings of Gregor Mendel with regard to crossing different individuals and their division into dominant and recessive properties and hybrids as a stimulus for the investigation of the “inner growth factors of the plant”. He applied these percentages to the increase in yield when a growth factor was increased (E. A. Mitscherlich, 1948). This results in a logarithmic function as “a general law of nature, which should appear wherever a quantity ‘y’ gradually approaches a finite maximum value with the increase of a quantity ‘x’” (E. A. Mitscherlich, 1954). E. A. Mitscherlich put the law of action of growth factors into the formula

log (A – y) = log A – c (x + b),

where A denotes the maximum yield, b the amount of nutrients already present in the soil, c the action factor (= action value) of the relevant growth factor or nutrient, x the amount applied as fertilization and y the current yield. From this it can be deduced that “namely the increase in yield brought about by increasing a growth factor is proportional to the yield missing from a maximum yield. This clearly shows that the increase in yield has to decrease the larger the amount of x is already available ”(E. A. Mitscherlich, 1954). In the ideal case, the increases in the first unit of a growth factor are 50% of the possible maximum yield, but only 25% for the second unit, 12.5% for the third, 6.25% for the fourth and 3.125% for the fifth: The Increases decrease significantly as the respective maximum yield is approached. It should not go unmentioned that even E.A. Mitscherlich had to recognize that the economists who dealt with this law wrongly called these facts the “law of decreasing land yield” and not the “law of decreasing increase in yield” (E.A. Mitscherlich, 1948). The following examples should contribute to the thematic attunement.

Example No. 1: Almost every healthy person is able, especially in their youth, to continuously cover an appropriate test distance in a certain period of time. Depending on the general physical condition and some training hours, it will be possible to cover this given distance in an ever shorter period of time, depending on the time spent and the intensity of these preparations, whereby the level of initial success in the further training hours is no longer so clear. For peak times in Olympic competitions or a full marathon, however, every athlete needs a significantly higher amount of training, endurance and patience in order to gain a small amount of time. Ultimately, only a very small amount of time can be saved through an enormously increased training effort. The first marathon runner, who beat the two-hour mark for a full marathon (42.195 km) in Vienna for the first time in autumn 2019, trained hard mentally and physically for this run for years.

Example No. 2: A feeling for rhythm and interpretation as well as a certain vocal ability is given to almost everyone. In order to get into the high spheres of a perfect art of singing, besides talent and a well-founded training, you need to practice for several hours a day. Nevertheless, only a few are allowed to reach the highest levels of artistic creativity, and this only thanks to a very high level of effort, such as constant and intensive practice under the guidance of excellent music teachers.

Example No. 3: In the age of the automobile, almost every citizen in industrialized countries has a driver’s license and also drives a car. How well or how badly an individual drives is only up for discussion here, but the steep, exhausting and also costly path from an average driver to a place in the cockpit of a Formula 1 car only very few people reach. All physical and mental abilities of the pilot are required here. If you follow the training before every Grand Prix run, you can see not only the high technology of a car, but also the enormously increased effort required to achieve a (even) higher speed. It would be an interesting study to calculate how expensive it is to gain a second per lap, especially when top teams win tenths or hundredths of a second.

Example No. 4:
The Mitscherlich law can be clearly seen in pioneering projects and work of any kind. At the beginning, the initial stages of a project are quickly overcome by those who have a pioneering spirit and are almost skipped over by the initial successes. But the vigor of the first few hours soon waned, as you had to recognize that the additional yield per unit of effort is lower and can no longer be seen as clearly. As a result, the desire for further commitment also decreases. This situation often occurs where a low starting level was assumed. In this context, a further confirmation of the law by A. E. Mitscherlich should be mentioned with the information on income and, above all, income growth. Above all, it must be noted from which (yield) level the growth rates are shown. If a very low starting level is the basis, then high growth rates should come as no surprise. However, if the starting level is already high, then even low growth rates often document a high level of effort, combined with high productivity. These facts should be borne in mind when comparing growth rates in each industry in developed and developing countries.

Example No. 5:
A noteworthy contribution to the question of maximization can be found in the review of a lecture that A. Haiger gave with the title “Optimizing nature, maximizing man” (A. Burgstaller, 2020). A. Haiger’s key statements begin with the question of why a cow that delivers 12,000 liters of milk per year and has eaten 3,000 kg of food for it receives an award, since the cow’s profitability is measured by the maximum milk yield with high energy density per lactation, however, the useful life is of secondary importance. This averages 3.8 years for a cow in Austria. Furthermore, the incentive to achieve high lactation performance with high energy density – that is, to produce concentrated feed (often imported from overseas) – displaces the natural food source grass and thus creates food competition with humans. It is questionable whether and how in the future around 10 billion people and cows, who eat 2000 to 3000 kg of grain per year, can be fed. Wouldn’t it be forward-looking – according to A. Haiger’s final statement – to aim for an optimum of eight calves with an annual output of 6000 l milk per year in animal breeding and husbandry instead of a cow with 8,000 l milk per year and six calves as a maximum? We live in a time in which in certain sectors (only) perfectionism is asked for, demanded and also paid (correspondingly high). Considerations not to strive for the maximum through enormous effort, but only to be satisfied with an optimum with a reasonable effort (“Mastery shows the master”), are hardly heard, even less applied. Reaching for doping agents is often used as an excessive increase in achieving a new maximum yield (= “increased” maximum output), the side effects of which are usually concealed and one is only dependent on vague indications in the course of investigations in (the few) uncovered cases. Is burnout the logical consequence of a performance spiral that has gotten out of control? Are not all of these human-initiated activities and their results based on E. A. Mitscherlich’s law of diminishing surplus yield – or should this be a mistake? Perhaps the author of these lines has succeeded not only in recalling the brilliant insights of E. A. Mitscherlich, but in interpreting them in a new and expanded manner. They could initiate a rethink in our everyday actions.
literature Burgstaller, A. (2020): Nature optimized, man maximized. Blick ins Land, No. 1, January 2020, Vienna. Mitscherlich, E. A. (1948): The laws of earnings. German Academy of Sciences in Berlin, lectures and writings, no.31, Akademie-Verlang, Berlin. Mitscherlich, E. A. (1954): Soil science for farmers, foresters and gardeners in plant-physiological orientation and evaluation. Ed. P. Parey, Berlin and Hamburg.