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Analyzes the carbon and oxygen isotopic composition of seventy-nine samples of biogenic carbonates from the Mainz Basin Tertiary. salinity trends derived from isotope data; Salinity cycle ranging from fresh water-brackish towards marine and brackish-fresh water.

The article focuses on the carbon-nitrogen relationship of soils in particular relation to the coniferous forests of the Himalaya Mountains Region. It describes the geography and geology of two areas in the Himalayan Range, the Kulu Forest Division and the Kashmir Valley. It mentions that the soil profiles of the Kulu area belong to the podsol and brown earth groups and states the soil characteristics of two important geological formations of the Kashmir Valley. It informs that a fair divergence in the carbon : nitrogen ratio exists between the soil profiles belonging to the different groups like podsol and brown earth, and discusses the various methods used in comparing the carbon : nitrogen ratio of the soil profiles.

Published and unpublished data on the amounts of organic matter and nitrogen in the surface soils of the West African savanna are reviewed. In general, amounts are small; the mean carbon content of soils from 605 well-drained sites was 0.68 per cent. Two important factors governing amounts of organic matter in well-drained soils appear to be the clay content and a moisture factor related to the length of the wet season and represented here by mean annual rainfall. Multiple linear regression on soil clay content and rainfall accounted for 46.5 per cent and 57.2 per cent, respectively, of the observed variability of soil carbon and nitrogen contents. These findings suggest that the low levels of organic matter in savanna soils arise from their predominantly sandy nature and from the relatively low rainfall. In poorly drained soils organic matter levels are higher but are less significantly related to clay content and rainfall. The influence of human interference and of parent material and altitude on organic matter is demonstrated in the context of geographically limited areas within the savanna for which more detailed information was available. [ABSTRACT FROM AUTHOR]