We investigated the varying concentrations of bound amino acids in humic acids (HA) extracted from soils under both crop rotation and continuous cropping of rye. The experiment was created in 1957. Since then, winter rye had been grown continuously and also the sequence of the 7 yr rotation had been started: potato, spring barley, alfalfa, alfalfa, oil seed rape, winter rye, and winter rye. Soils were fertilized with NPK and manure. Continuous cropping of rye increased total acidity of soils and the contents of carboxylic and phenolic groups in HA. The total amounts of the bound amino acids in HA from soils under crop rotation were higher than from continuous cropping of rye. Fertilization with NPK increased the contents of bound amino acids more than manure. Neutral amino acids dominated in all samples of HA, and basic amino acids had the lowest concentrations. In both types of cultivation, glutamic acids, glycine, alanine, valine, and lysine dominated. The proline contents in HA from continuous rye cropping were higher than in HA from soils under crop rotation. The concentrations of β‐alanine and lysine were higher in HA from crop rotation indicating a higher microbial biomass since these compounds are typical constituents of bacteria cell walls.

Concentrations of calcium, magnesium, and carbon in inorganic compounds were measured in the groundwater crossing a shelterbelt. The differences among the concentrations of Ca, Mg, and C in inorganic compounds were attributed solely to the width of the shelterbelt. This biogeochemical barrier efficiently decreased the concentrations of chemical substances: the fall in the dry mass was 30-75%, in Ca 20-54%, in Mg 46-72%, and in C in inorganic compounds 58-71%.

Forms of nitrogen , N-NH 4 + , N-org) and phosphorus (P-PO 4 -3 , P-org) were investigated in ground and surface water as well as in precipitation and run-off. The highest concentration of all the investigated compounds was determined in the drain and in run-off. This investigation shows that afforestations and small ponds function as very efficient biogeochemical barriers with regard to N-NO 3 -and P-PO 4 -3 . They do not, however, limit the spread of P-org.

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Handelsübliches β‐Sitosterin (I) wird durch aufeinanderfolgende Acetylierung, katalytische Hydrierung, Hydrolyse und Oxidation in das Keton (II) umgewandelt, das bei Reaktion mit Äthylformiat in Gegenwart von Na‐äthoxid unter N2 und anschließendem Ansäuem in das Hydroxyke‐ ton (III) übergeht.

Umsetzen des Anhydrids (I) mit den Hydrazinen (II) liefert die Pyridazinone (III), die zu den O‐Acetylderivaten‐(IV) acetyliert werden.