The Nutrient Challenge
Nitrogen and phosphorous are two key nutrients. Together they play an important role in the global and local sustainable development agendas. The use of these nutrients is key to growing crops and thus to the world’s food security. However, in some parts of the world farmers do not have access to enough nutrients to grow crops and feed growing populations. But in many other parts of the world there is an ‘excess’ of nutrients in the environment as a result of industrial and agricultural activity and has profound impacts, from pollution of water supplies to the undermining of important ecosystems and the services and livelihoods they support.
The result is a seeming divide between societal needs for food and energy and a complex web of adverse environmental impacts which undermine the natural resource base and the services and livelihoods it provides. This divide – ‘the nutrient challenge’- is set to intensify, to the cost of countries, as population, food and energy demands increase.
Some key facts may help to visualize the challenge that we are faced with
- Human activities produce around 120 m tonnes of reactive nitrogen each year, much of which (nearly two thirds) ends up polluting air, water, soil marine and coastal areas, and adding harmful gases to the atmosphere;
- Some 20 m tonnes of phosphorous are mined every year and nearly half enters the world’s oceans - 8 times the natural rate of input;
- Between 1960 and 1990 global use of synthetic nitrogen fertilizer increased more than sevenfold, while phosphorus use more than tripled;
- One half of the world’s population is now thought to depend on nitrogen and phosphorous fertilizers for the production of their food – much of the fertilizers is not used by the crops;
- An estimated 90% of wastewater in developing countries is discharged untreated into waterways and coastal areas;
- Worldwide, the number of coastal areas impacted by eutrophication caused by excess nutrients stands at over 500;
- Dead zones in the world’s oceans have increased from 10 cases in 1960 to 405 documented cases in 2008 (169 identified hypoxic areas, 233 areas of concern and 13 systems in recovery);
- Many of the world’s freshwater lakes, streams, and reservoirs suffer from eutrophication – millions of people depend on wells for their water where nitrate levels are well above recommended levels;
- More than 90% of the world's fisheries depend in one way or another on estuarine and near-shore habitats;
- Nitrous oxide is a powerful greenhouse gas –estimated to be responsible on current levels for about 11% of the net anthropogenic global warming potential from such gases.
The accelerated use of nitrogen and phosphorous is at the centre of a complex web of development benefits and environmental problems. They are key to crop production and half of the world’s food security is dependent on nitrogen and phosphorous fertilizer use. But excess nutrients from fertilizers, fossil fuel burning, and wastewater from humans, livestock, aquaculture and industry lead to air, water, soil and marine pollution, with loss of biodiversity and fish, destruction of ozone and additional global warming potential.
The problems will intensify as the demand for food and bio-fuels increase, and growing urban populations produce more wastewater. This will be at a growing economic cost to countries in the undermining of ecosystems, notably in the costal zone, and the services and jobs they provide.
In this backdrop, the key question that needs to be answered is
‘How to promote effective nutrient management, minimising negative impacts on the environment and human health, while maximising their contribution to global sustainable development and poverty reduction?’
The Global Partnership on Nutrient Management (GPNM) has been launched to address this challenge. The GPNM is a global partnership of governments, scientists, policy makers, private sector, NGOs and international organisations. The Partnership recognised the need for strategic advocacy and co-operation at the global level in order to communicate and trigger productive discussion not only on the complexity of the nutrient challenge but also the opportunities for cost effective policy and investment interventions by countries.