Among the goals of environmentally sound waste treatment is the recycling of organic wastes. The most practiced options are composting and anaerobic digestion, both processes being carried out by microorganisms. This book provides an overview of the various ways microbes are doing their job and gives the reader an impression of their potential. The sixteen chapters of this book summarize the advantages and disadvantages of treatment processes, whether they are aerobic like composting or work without oxygen like anaerobic digestion for biogas (methane) production. These chapters show the potential of microorganisms to create valuable resources from otherwise wasted materials. These resources include profitable organic, humus-like soil conditioners or fertilizer components which are often suppressive to plant diseases. Composts may thus improve soil carbon sequestration, or support sustainable agriculture by reducing the need for mineral fertilizers or pesticides. If anaerobic digestion is used, the biogas produced may replace fossil fuels. Thus, proper biological waste treatment with the help of microorganisms should contribute to a reduction of anthropogenic greenhouse gas production.

The use of renewable bioenergy is increasing, and so is the production of associated wastes: biomass ashes. This book presents eleven chapters on the options for recycling such biomass ashes, ranging from their use as fertilizer in agriculture and forestry to their application as a supplement for the production of cement-based materials or bricks. The book also examines the pros and cons for each of the different uses of biomass ashes.

Research on decomposer communities of terrestrial ecosystems for a long time has focussed on microbial biomass and gross turnover parameters. Recently, more and more attempts are made to look beyond the biomass, and more specifically determine functions and populations on a smaller scale-in time and space. A multitude of techniques is being improved and developed. Garland and Mills (1991) triggered a series of publications on substrate utilization tests in the field of microbial ecology. Despite several promising results for different applications in different laboratories, many problems concerning the assay and the interpretation of results became evident. After individual discussions on the approach with colleagues from various laboratories we started to plan a workshop on the matter. The response on our first circular was extraordinary, and instead of a small workshop it became a meeting with almost 150 participants. The meeting was named 'Substrate use for characterization of microbial communities in terrestrial ecosystems' (SUBMECO) and was held in Innsbruck, Austria, from Oct. 16-18, 1996. The very focussed scope attracted enthusiastic advocates of the approach, and also serious critics. Some of the topics concerned improvements of current inoculation and incubation techniques, ranging from sample pre-treatment, inoculum density and incubation temperature to statistical data handling. New methods for calculating microbial diversity were proposed, as well as bootstrap methods that allow statistics with many variables on a relatively low number of replicates.

The use of renewable bioenergy is increasing, and so is the production of associated wastes: biomass ashes. This book presents eleven chapters on the options for recycling such biomass ashes, ranging from their use as fertilizer in agriculture and forestry to their application as a supplement for the production of cement-based materials or bricks. The book also examines the pros and cons for each of the different uses of biomass ashes.

Composting is increasingly used as a recycling technology for organic wastes. Knowledge on the composition and activities of compost microbial communities has so far been based on traditional methods. New molecular and physiological tools now offer new insights into the "black box" of decaying material. An unforeseen diversity of microorganisms are involved in composting, opening up an enormous potential for future process and product improvements. In this book, the views of scientists, engineers and end-users on compost production, process optimisation, standardisation and product application are presented.

Composting is increasingly used as a recycling technology for organic wastes. Knowledge on the composition and activities of compost microbial communities has so far been based on traditional methods. New molecular and physiological tools now offer new insights into the "black box" of decaying material. An unforeseen diversity of microorganisms are involved in composting, opening up an enormous potential for future process and product improvements. In this book, the views of scientists, engineers and end-users on compost production, process optimisation, standardisation and product application are presented.