The German metal industry is confronted with an enforcing international competition,rising prices of energy and commodities, the increasing relevance of sustainable economy,political demands and incentives such as emission trading. To meet these challenges it isessential for companies to further improve resource and energy efficiency and to reduceCO2 emissions. Usually, efforts concerning these objectives focus on new orimproved single processes. In contrast, the presented approach extends the considerationsto the inter-company perspective and considers multiple processes from ferrous andnon-ferrous metals industry which are linked by material flows. Our considerations focuson residue flows in the iron and steel as well as the zinc industry. Steel production inintegrated steelworks or electric steel plants involves the formation of large amounts ofby-products, e.g. dusts, sludges or slags. These contain valuable substances such as ironor zinc and can be further processed by internal re-feeding or external recycling, e.g. byspecialized companies, particularly Waelz kiln plants or the DK process. The latterproduce zinc concentrates for the zinc industry. Changes in the modes of operation of oneor more process can therefore affect the connected processes. We investigate strategies tofurther reduce landfilling and to efficiently allocate by-products to internal andexternal recycling options within the scope of the sketched network. We develop flowsheetmodels for representative processes within the regarded industries in Germany. With anElectric Arc Furnace (EAF), an integrated steelworks, two recycling companies, and ahydrometallurgical zinc plant the major processes of the German iron, steel and zincindustries are considered. We derive linear input-output functions for each of theprocesses by means of multiple linear regression analysis which we apply on results ofsystematically varied flowsheet simulation runs. These functions are used in a system oflinear equations, forming a material and energy flow model of the regarded network. Themodel is applied to identify and assess strategies and measures to enhance resource andenergy efficiency and to reduce climate relevant CO2 emissions by scenario andsensitivity analyses. Thus, technical and economical barriers of inter-company measurescan be overcome by identifying strategies which are technologically feasible and favorablewith regard to the named objectives.

Agroecology is the development and application of ecological theory to the management of agricultural systems, according to the specific land and other resources available. Beyond the biological and climatic dimensions of agriculture and ecology, there is growing appreciation of the influence of social, economic, and political factors on the structure and success of farming systems. This broader field is becoming known as “agroecology and sustainable development.” Expansion of the conventional curriculum to include integrative themes is essential because of the need for students to appreciate a whole farm focus for analysis, to understand the impact of socio-economic factors, and to further develop their abilities to link people and environment. Two courses are proposed and described in detail “Biology of Agroecosystems” includes study of system structure and function, cycles and interactions among components, system development and performance, and the importance of resource conservation and use. “Agroecology and Sustainable Agricultural Development” includes a survey of systems around the world, an evaluation of resources and their use, the environmental impact of agriculture, the relationships between society and agriculture, the applications of agroecology to rural development, and some projections of alternative future strategies for food production. Future agricultural professionals need to understand how improvement of agroecosystems is closely linked to economic, cultural, and political systems, and how they are both enhanced and constrained by factors beyond biology and climate.