Opening address: An outside view of environmental biogeochemistry.- Early biogeochemical systems: keynote address.- Precambrian genetics.- The universe of porphyrins.- Antiquity of photosynthesis: possible constraints from Archaean carbon isotope record.- Oxygen and ozone evolution in palaeoatmospheres.- Past oxygen levels; some evidence from uranium deposits.- Timing and relationships among Precambrian crustal and atmospheric evolution and banded iron-formations.- Chemical conditions for the precipitation of banded iron-formations.- Environmental biogeochemistry: keynote address.- Lake sediments: chemical composition and some aspects of their formation and diagenesis.- Lake sediments: algal availability of Lake Burley Griffin sediment phosphorus.- Bacterial populations in two saline Antarctic lakes.- Measurement of bacterial biomass in sandy sediments.- Carbon flow within the southwest arm of Port Hacking, N.S.W..- In situ experimentation with anaerobic sediments: some biogeochemical applications.- Sedimentological and geobiological studies of intertidal cyanobacterial mats in north-eastern Spencer Gulf, South Australia.- The microbial geochemistry of Solar Lake, Sinai.- Comparative organic geochemical studies of recent algal mats and sediments of algal origin.- Comparative analysis of stromatolitic and other microbial kerogens by pyrolysis — hydrogenation — gas chromatography (PHGC).- Lipid productivity of a high Andean lake.- The contribution of the chlorophyll-carotenoid protein complexes of brown seaweeds to the petrogenic silt of the oceans.- Biological methanogenesis in sediments and sanitary landfills.- Role of methane-producing and sulfate-reducing bacteria in the destruction of organic matter.- Methane in a saline Antarctic lake.- The production of methylated sulfur compounds by marine phytoplankton.- Influence of selenium compounds on the reduction of sulfur compounds and associated sulfur isotope fraction in Clostridium pasteurianum.- Microbiological nitrous-oxide production: implications for the global nitrogen cycle.- Mechanisms of nitrous oxide production in soils.- The measurement of denitrification in soil using 13NO3.- Nitrogen diagenesis in marine sediments: evidence for suboxic and anoxic conversion of organic N to N2 gas.- Regional nitrogen mass balance model for the Florida peninsula.- Process controlling the nitrogen cycle in the atmosphere over Australia.- Different forms of microbial manganese oxidations and reductions and their environmental significance.- The role of surface attachment in manganese oxidation by freshwater hyphomicrobia.- Electron transfer coupled to Mn(II) oxidation in two deep-sea Pacific Ocean isolates.- Electron microscopic analysis of metal-depositing microorganisms in surface layers of Baltic Sea ferromanganese concretions.- Mineralogical, geochemical, and microbiological aspects of iron deposition from ground water.- Consequences of anaerobiosis on metal-organic interactions in two ponds of the southeastern United States.- Physico-chemical models for heavy metal transport in streams.- Man’s effect on stratospheric ozone.- The trace composition of the atmosphere and the global atmospheric ozone content.- Effects on the carbon cycle due to human impact on forest ecosystems.- Sewage sludge fertilization in pine forests: ecological effects on soil and vegetation.- Polychlorinated biphenyls in sediments and mussels from Port Philip Bay, Victoria, Australia.- Water pollution as a consequence of land disturbance in south-west of Western Australia.- Interpretation of soil water quality for agricultural production.- Facultative thermophilic Thiobacillus-like bacteria in metal leaching.- The leaching of sulfide ores by a thermophilic bacterium.- A scanning electron microscopy study of the colony morphology of Thiobacillus ferrooxidans.- A micro-calorimetric study of U(IV)-oxidation by Thiobacillus ferrooxidans and ferric iron.- A micro-calorimetric study of the metabolic activity of several Thiobacillus species.- Leaching of copper-bearing mineral substrates with wild microflora and with laboratory-bred strains of Thiobacillus ferrooxidans.- Isolation of iron- and sulfur-oxidising bacteria from mine water in Japan and some investigations on the leaching of sulfide ores.- The microbial role in pyrite oxidation at alkaline pH.- The effect of chemical and biological redox reactions on the growth of Thiobacillus thiooxidans.- Inhibition by pyrite of bacterial iron oxidation activity.- Sulfur and hydrogen ion buffering in pyritic strip-mine spoil.- Liquid dispersion in trickle flow through ore dumps.- The comparison of biological and chemical leaching: Heap leaching using Thiobacillus thiooxidans.- A reactor system for mineral leaching investigations.- A multi-company sponsored research program to study the biologically assisted ferric iron leaching of uranium minerals.- Bacterial leaching of a carbonate-bearing uranium ore.- Influence of attrition grinding on the recovery of copper from a high-grade chalcopyrite concentrate by the BSE-process.- Laboratory studies on mineral leaching.- An efficient method for the production of leaching medium.- Bacterial leaching of manganese ores.- Bacterial leaching of antimony and bismuth-containing ores and sewage utilization.- Water movement caused by monsoonal rainfall in an overburden dump undergoing pyritic oxidation.- Temperature distribution in an overburden dump undergoing pyritic oxidation.- Environmental studies of flooded opencuts.- Factors in metal leachate toxicity.- Biological methods to remove selected inorganic pollutants from uranium mine waste water.- Biochemical beneficiation of mining industry effluents.- Control of environmental pollution from mining wastes(metalliferous muds, Red Sea).- Desulfurization of coal by Thiobacillus ferrooxidans.- Mine waste pollution control at Captains Flat.- The revegetation of mine spoil.