Friday marks the annual observance of World Water Day, during which issues around freshwater management come to the forefront. One of the major threats to the quality of freshwater resources is pollution from the land. In the past 50 years, use of synthetic nitrogen and phosphorous fertilizers have risen substantially (9 and 3 fold, respectively), and the upward trend is expected to continue. And yet, over 80% of nitrogen and up to 75% of phosphorous used is in fact lost to the environment through runoff, erosion, and greenhouse gas emissions. While the impacts are not relegated to water, nutrient overload does cause dead zones at the mouths of rivers and can contaminate aquifers and surface water used for drinking, irrigation, and wildlife habitat.
Obviously this is a major threat to address. In response a Global Partnership on Nutrient Management, led by the United Nations Environment Programme, has formed to provide a multi-stakeholder platform for governments, UN agencies, scientists, and the private sector to collaborate and coordinate about best practices and assessments needed to “nutrient-proof” policy and investments. A product of this alliance, the report Our Nutrient World was released in mid-February and serves as a global overview of nutrient management.
It’s all about balance. The report is founded on the premise that in order to feed a growing global population, external sources of nitrogen, phosphorous, and other nutrients will be necessary. Too little, and land degrades and harvests begin to fail. Too much, and we’ve created a global web of pollution. 50 experts, led by Mark Sutton at the UK’s Centre for Ecology and Hydrology, carried out research on the state of nutrient use and (and perhaps misuse). Specifically, the researchers propose a package of ten key actions across sectors and including personal behavior to reduce these pollution threats, and makes recommendations for shared action by governments, business and citizens. Specifically with regards to agriculture, improving nutrient use efficiency in crop and animal production, and increasing the fertilizer equivalence value of animal manure, are proposed as key objectives.
But nutrient management is more complex than sector-based solutions. Because of the nature of nutrient cycling in the environment, taking a ‘trans-boundary’ perspective to nutrient management came through as a particularly important theme. According to the report, “such inter-connections require consensus on an international approach that takes account of local and regional conditions, while addressing the necessary improvement in nutrient use efficiency at the global scale.” Moreover, issues of nutrient pollution are often addressed in a very sector or impact-specific, without accounting for the many links. The report calls for an intergovernmental framework to address these issues, and proposes a road map of how such an agreement would look.
Finally, the authors suggest key actions for ‘integration and optimization’, in particular optimizing for spatial and temporal components of nutrient flows. For example, this might mean bringing together animal and crop agriculture to make better use of the animal manures. Planning decisions at different scales can play a role in siting certain activities and landscape elements to achieve the most efficient outcomes, reducing pollution and maintaining production.
Of course, the report outlines major barriers to developing and implementing national policies and an inter-governmental framework to address these imminent challenges. On Friday, a guest post will highlight one mechanism to address the issue of water quality degradation, payment for watershed services (PWS), operating at the local level rather than these larger scales.
Sutton, M.A., et al. 2013. Our Nutrient World: The Challenge to Produce More Food and Energy with Less Pollution. Global Overview of Nutrient Management. Centre for Ecology and Hydrology, Edinburgh on behalf of the Global Partnership on Nutrient Management and the International Nitrogen Initiative.
Related article on Ensia – Nitrates on Tap