ABOUT
Phosphorus is an essential macronutrient alongside nitrogen and potassium. It is an indispensable nutrient required by all living organisms, including humans. Excess phosphorus, like the other key nutrient, nitrogen, depletes soils of their richness and pollutes lakes, rivers and the ocean in a process known as eutrophication.
Phosphorus pollution also contributes to biodiversity loss and the degradation of ecosystems on which humanity depends. There is a great need for sustainable management of phosphorus to reduce nutrient loss and ecosystem disturbances and promote phosphorus recovery and reuse.
ECOLOGICAL STATUS AND TRENDS
Phosphate rock is the main source of easily accessible phosphorus for manufacturing synthetic fertilizer and has been produced in large quantities since World War II. When phosphorus is not adequately managed, it leads to an imbalance in nutrient ratios.
Too much phosphorus cause problems, but too little phosphorus can also be detrimental. The global cost of phosphorus pollution is estimated to be US$265 billion per year. Changes to the phosphorous cycle and the rate that phosphorus is moving through parts of this cycle has now reached a point where there is a high risk of fundamental changes to the earth’s systems.
WHY DOES IT MATTER
A deficiency of phosphorus can cause health problems for humans, animals, and plants. Plants need phosphorus to photosynthesize. Crops that do not have enough phosphorus will not grow to their fullest extent, take longer to mature, and have lower yields. Equitable access to phosphorus and its appropriate use is an important part of achieving long-term food security.
Pollution from excess phosphorus is one of the main direct drivers of biodiversity loss. It undermines ecosystem function and ecosystem services in soils, lakes, rivers streams and coasts, disrupting the balance of nutrient availability, leading to eutrophication. In freshwater and coastal ecosystems, this causes a rapid acceleration of algal growth which can block light and deplete oxygen. In extreme cases, it can result in areas known as dead zones.
In the Caribbean, eutrophication has been linked to vast quantities of sargassum washing up on the beaches, causing social, environmental, and economic problems. The response of ecosystems to pollution can be compounded by the impacts of climate change and the other way around. Warmer water carries less oxygen; it can augment algal blooms and/or amplify the toxic cocktail of pollutants.
WHAT WE DO
The management of phosphorus is vital for achieving several of the Sustainable Development Goals (SDGs), in particular SDG-2 (Zero hunger), SDG-6 (Clean water and sanitation) and SDG-14 (Life underwater).
UNEP hosts the Global Partnership on Nutrient Management, launched in 2009. It promotes effective nutrient management, particularly of nitrogen and phosphorus, to both achieve food security and protect the environment.
UNEP’s efforts to control the environmental fallout of phosphorus come amid a wider global effort to rein in pollution, which received a boost last year with the landmark Global Framework on Chemicals. Based around 28 targets, the framework sets out a roadmap for protecting people and the planet from harmful chemicals and waste. UNEP will manage a trust fund that will help implement the agreement.
As the leading global authority on the environment, UNEP is also helping countries implement the Kunming-Montreal Global Biodiversity Framework, including Target 7, which addresses phosphorus. The framework calls for a 50 per cent reduction in excess nutrients lost to the environment by 2030 and for the risk from pesticides to be reduced by at least half.
FACTS
- Phosphorus compounds come from phosphate-containing rock.
- Phosphorus is a nutrient found in and required by all living things, including humans.
- Plants require phosphorus for photosynthesis and growth.
- The natural cycle of phosphorus is slow, playing out over millions of years.
- Phosphorus is an essential macronutrient alongside nitrogen and potassium.
- Phosphorus underpins global food systems and food security. Food production is undermined by the lack of available and accessible phosphorus.
AGREEMENTS AND CONVENTIONS RELATED TO UNEP’S MANDATE ON PHOSPHORUS
- Nutrient management has been the subject of previous commitments for environmental action by the United Nations Environment Assembly, including two specific resolutions adopted to address sustainable nitrogen management (UNEA Resolutions 4/14 and 5/2).
- The Kunming-Montreal Global Biodiversity Framework (GBF) tackles phosphorus in Target 7, which addresses reducing excess nutrients lost to the environment as well as reducing the risk from pesticides.
RELATED PUBLICATIONS
Facts about sustainable phosphorus management | UNEP - UN Environment Programme
Understanding phosphorus: global challenges and solutions
What is Sustainable Phosphorus Management and why do we need it?
