Deuterium Content in Organic Material of Hosts and Their Parasites

Abstract

The basic source for the deuterium in the organic material of an autotrophic plant (using water as a hydrogen source) is the medium water, and in terrestrial plants this means the soil water. The deuterium content of this soil water again depends normally mainly on its concentration in precipitation. Condensate from the water vapor is enriched in deuterium relative to the vapor with the result that the remaining vapor will be increasingly depleted in deuterium as moisture is removed from the air. Since the absolute water content of the atmosphere is temperature-dependent, an increasing depletion of deuterium in precipitation will result as a consequence of decreasing temperature. This is termed the “climatic effect” (cf. Schiegl 1970). The variations in deuterium content of natural waters caused by condensation and evaporation lie between +100‰ and −400‰ with respect to the deuterium content of the ocean [standard mean ocean water (SMOW)].