International Association for Lichenology: the early years.
One of the main purposes of the International Association for Lichenology (IAL), inaugurated in 1967, was to establish a Newsletter in order to provide a forum for lichenologists worldwide to communicate with each other. In consequence, the early history of the IAL is in large degree the story of the International Lichenological Newsletter (ILN). Those responsible for organising the IAL at this time were essentially the editors of the Newsletter, hard-working people, collating hundreds of short notes on lichenologists and their current projects and opinions from all over the world, as well as reports of meetings and social events. Although the possibilities of communication have increased enormously in recent years, the function of IAL and its Newsletter remain the same, and the initial enthusiasm for exchanging ideas and results and reporting meetings continues undiminished.
Progress and problems in lichenology in the eighties
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Pyrite multiple-sulfur isotope evidence for rapid expansion and contraction of the early Paleoproterozoic seawater sulfate reservoir
Abstract Earthʼs oxygenation is often described in terms of two unidirectional steps at the beginning and end of the Proterozoic Eon, separated by a long-lived intermediate redox state. Recent work defines a more complicated path to oxygenation, exemplified by an apparent drop in oxidation state following the early Paleoproterozoic Lomagundi carbon isotope excursion. The timing of this proposed drop in oxidation state is not well constrained, and it is not clear how it relates to redox conditions during the remainder of the Proterozoic. Here we present a study of pyrite multiple-sulfur isotopes, supported by Fe speciation and organic carbon isotopes, from early Paleoproterozoic black shales. We find evidence for the rapid expansion of the seawater sulfate reservoir during the Great Oxidation Event at ca. 2.3 Ga followed by a subsequent contraction in the size of the seawater sulfate reservoir at ca. 2.05 Ga. This scenario is consistent with the emerging view of a rise and fall in surface oxidation state during the early Paleoproterozoic. Comparison of our new data to other records of the seawater sulfate reservoir suggests that the elevated sulfate concentrations that characterize the early Paleoproterozoic did not return until the late Neoproterozoic.