Unlike oil, which is lost once it is used, phosphorus can be recovered and used over and over again if present in sufficient concentrations. Between the phosphate rock mine and the food in our stomachs, up to 80% of P is lost in the process from fertilizer production, application on fields, uptake by crops, food processing and retailing and final consumption. This tells us that in addition to increasing efficiency in the entire process we can look for opportunities to increase recovery of P in crop residues, food waste in supermarket dumpsters and household bins, manure, human excreta, struvite and other sources such as bone meal, ash and algae.
A key opportunity to meeting the goal of global food security lies in the often overlooked link between addressing hunger and sanitation. Phosphorus (P) is a critical nutrient input in agriculture and its global reserves are being rapidly depleted. It is also a constant nutrient stream in sewage emerging from human settlements that is often considered an environmental pollutant. Each year, we produce 3 million tonnes of P in our urine and faeces globally. If displaced nutrients (like P) are recirculated back to agriculture from where they first came, we can sustain food production into the future and decouple communities’ dependence on globalised and increasingly inaccessible P fertilizer markets.
excerpts from:
Cordell (2008), The Story of Phosphorus, poster presented at Food Security and Environmental Change Linking Science, Development and Policy for Adaptation, Session 18: Institutional and policy challenges for agro-ecosystem management in relation to food security. 2 - 4 April 2008, University of Oxford, UK. http://www.gecafs.org/FoodConferencePresentations.htm
more Phosphorus Recovery content to come |
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Last Updated on Wednesday, 07 October 2009 00:07 |
Phosphorus recovery