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Abstract: SNV 1 [1] Netherlands Development Organisation. is supporting the implementation of market-based domestic biogas programmes in different countries in Asia and Africa with a view to establish a commercially viable biogas sector. Till the end of 2009, some 300,000 fixed-dome biogas plants of sizes ranging from 4 m3 to 15 m3 have been installed. These plants produce about 600,000 m3 of biogas each day which supplements more than 3000 tonnes of fuel wood. Benefits of biogas plants have positive impacts on basic livelihood indicators as well as rural economic development. The key to success has been the multi-stakeholder sector development approach in optimising organisational and institutional capacities within national contexts. This paper highlights approaches, achievements, lessons learnt and other relevant aspects of domestic biogas programmes in developing countries. [Copyright &y& Elsevier]

Abstract: The phosphorus (P) cycle has been significantly altered by human activities. For this paper, we explored the sustainability of current P flows in terms of resource depletion and the ultimate fate of these flows. The analysis shows that rapid depletion of extractable phosphate rock is not very likely, in the near term. Under best estimates, depletion would be around 20–35%. In worst case scenarios, about 40–60% of the current resource base would be extracted by 2100. At the same time, production will concentrate in Asia, Africa and West Asia, and production costs will likely have increased. As there are no substitutes for phosphorus plant nutrients in agriculture, arguably even partial depletion of P resources may in the long run be relevant for the sustainability of agriculture. Consumption trends lead to large flows of phosphorus to surface water and a considerable build-up of phosphorus in agricultural soils in arable lands. This may allow a reduction in future P fertiliser application rates in crop production. Results also indicate a global depletion of P pools in soils under grassland, which may be a threat to ruminant production. [ABSTRACT FROM AUTHOR]