Suchergebnisse

Cities have the capacity to play a key role in resource and pollution management through their decisions about organic waste. Often overlooked, but nevertheless essential, is the role that cities can play in increasing phosphorus (P) recycling because cities are consumers of large amounts of P-dense food and producers of vast amounts of P-rich waste. Most cities do not take advantage of this potential, seeing P as simply another part of organic waste to be disposed of elsewhere. For example, in Montreal, Canada, only 6% of P in waste is currently recycled. We used semi-structured interviews with key stakeholders (19), participant observation (over 1.5 years), and document review to identify key barriers and facilitators for Montreal to achieve a high level of organic waste recycling through composting. We found that a provincial law mandating 100% recycling of organic matter has great potential to facilitate increased P recycling. However, lack of a shared vision about the role of government, private sector, and citizens in producing high quality compost from waste products is a barrier that inhibits this potential. Cultural inertia, lack of knowledge, and lack of infrastructure also act as barriers to increasing composting in Montreal. Urban agriculture could be a means to overcome some of these barriers as it currently benefits from strong citizen support and is both a consumer and producer of compost. However limited access to potential garden space and training and diversity in desired fertilizer qualities among gardeners somewhat limit this potential. Investing in increasing social capital, and specifically in connecting urban agriculture to waste management objectives, and in linking key stakeholders to co-create shared visions about how to produce high quality compost may act as a stepping stone towards increasing Montreal citizens' knowledge about, and support for, increasing organic waste and thus P recycling.

International audience ; Phosphorus (P) is subject to global management challenges due to its importance to both food security and water quality. The European Union (EU) has promoted policies to limit fertiliser over-application and protect water quality for more than 20 years, helping to reduce European P use. Over this time period, the EU has, however, become more reliant on imported agricultural products. These imported products require fertiliser to be used in distant countries to grow crops that will ultimately feed European people and livestock. As such, these imports represent a displacement of European P demand, possibly allowing Europe to decrease its apparent P footprint by moving P use to locations outside the EU. We investigated the effect of EU imports on the European P fertiliser footprint to better understand whether the EU's decrease in fertiliser use over time resulted from P demand being 'outsourced' to other countries or whether it truly represented a decline in P demand. To do this, we quantified the 'virtual P flow' defined as the amount of mineral P fertiliser applied to agricultural soils in non-EU countries to support agricultural product imports to the EU. We found that the EU imported a virtual P flow of 0.55 Tg P/yr in 1995 that, surprisingly, decreased to 0.50 Tg P/yr in 2009. These results were contrary to our hypothesis that trade increases would be used to help the EU reduce its domestic P fertiliser use by outsourcing its P footprint abroad. Still, the contribution of virtual P flows to the total P footprint of the EU has increased by 40% from 1995 to 2009 due to a dramatic decrease in domestic P fertiliser use in Europe: in 1995, virtual P was equivalent to 32% of the P used as fertiliser domestically to support domestic consumption but jumped to 53% in 2009. Soybean and palm tree products from South America and South East Asia contributed most to the virtual P flow. These results demonstrate that, although policies in the EU have successfully decreased the domestic dependence on ...

Phosphorus (P) is subject to global management challenges due to its importance to both food security and water quality. The European Union (EU) has promoted policies to limit fertiliser over-application and protect water quality for more than 20 years, helping to reduce European P use. Over this time period, the EU has, however, become more reliant on imported agricultural products. These imported products require fertiliser to be used in distant countries to grow crops that will ultimately feed European people and livestock. As such, these imports represent a displacement of European P demand, possibly allowing Europe to decrease its apparent P footprint by moving P use to locations outside the EU. We investigated the effect of EU imports on the European P fertiliser footprint to better understand whether the EU's decrease in fertiliser use over time resulted from P demand being 'outsourced' to other countries or whether it truly represented a decline in P demand. To do this, we quantified the 'virtual P flow' defined as the amount of mineral P fertiliser applied to agricultural soils in non-EU countries to support agricultural product imports to the EU. We found that the EU imported a virtual P flow of 0.55 Tg P/yr in 1995 that, surprisingly, decreased to 0.50 Tg P/yr in 2009. These results were contrary to our hypothesis that trade increases would be used to help the EU reduce its domestic P fertiliser use by outsourcing its P footprint abroad. Still, the contribution of virtual P flows to the total P footprint of the EU has increased by 40% from 1995 to 2009 due to a dramatic decrease in domestic P fertiliser use in Europe: in 1995, virtual P was equivalent to 32% of the P used as fertiliser domestically to support domestic consumption but jumped to 53% in 2009. Soybean and palm tree products from South America and South East Asia contributed most to the virtual P flow. These results demonstrate that, although policies in the EU have successfully decreased the domestic dependence on mineral P fertiliser, in order to continue to limit global potential mineral P supply depletion and consequences of P losses to waterways the EU may have to think about its trading partners.