Barley, Alkylresorcinols, Resorcinolic LipidsThis study was carried out to compare grains of barley (Hordeum vulgare L. distichon) regarding contents and compositions of 5-n-alkylresorcinols. Mixtures of resorcinol homologues were isolated from acetone extracts from five barley cultivars. These polyketide metabolites were identified by chromatographic and spectroscopic means. The content and homologue patterns among different varieties were similar. The predominant compounds were 1,3-dihydroxy-5-n-heneicosylbenzene (C 21:0 ), 1,3-dihydroxy-5-n-nonadecylbenzene (C 19:0 ) and 1,3-dihydroxy-5-n-pentacosylbenzene (C 25:0 ). The alkylresorcinol concentrations, in contrast to their compositions, depended on environmental and agricultural factors.

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Summary. Bacterial, enzymatic and chemical analyses pointed to active micro-biological mineralization and transformation of penguin faeces in the maritime Antarctic. About 50% of C and N was volatilized during the flrst three weeks. Most of the N/NH3 contained in percolated water was oxidized to N/N03 in the sub-surface layer of the soil. Uric acid and chitin were degraded totally in the second stage of mineralization. The chemical composition of the water flowing from the penguin rookeries depended on the rookery location and size and the amount of precipitation. Ornithogenic soils that developed around large rookeries of pygoscelid penguins were formed by the action of guano solutions on loams and gravels. The main soil-forming process was phosphatization. A description is given of the sequence of appearance of phosphatic minerals, in relation to changes in the chemical composition of guano leachates, during their soaking and reactions through the soils (struvite, hydroxylapatite, leukophosphite, minyulite, taranakite, viviante). A quantitative estimate was made of the ornithogenic P flow in the penguin rookery at Llano Point. We found that at least 11% of the P brought by penguins from the sea to the land is annually accumulated in the form of phosphatic deposits.

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