Farmers have found an ally in a new report from the International Sustainable Development Institute (IISD), which says the responsibility for better phosphorus management cannot be carried by agriculture alone.
The report shifts the focus from phosphorus as a noxious nutrient that must be regulated to prevent it from damaging the environment, to phosphorus as a precious – and dwindling – non-renewable resource that must be used sparingly and carefully recycled from all aspects of the food chain.
The report even raises the spectre of unusual sources of supply for agriculture, including the cities, which could incorporate technology to recapture phosphorus from sewage to sell as fertilizer.
“Phosphorous is an indispensible resource that has been mismanaged to the point that we are jeopardizing our long-term food and water security. We need not look any further than Lake Winnipeg to see the consequences of that,” said IISD’s Vivek Voora, co-author of Peak Phosphorus: Opportunity in the making – why the phosphorus challenge presents a new paradigm for food security and water quality in the Lake Winnipeg Basin.
Lake Winnipeg, which receives most of the water draining from the Rockies to Lake Superior, is facing severe pollution from giant algae blooms stimulated by excess phosphorus from urban and agricultural sources.
Seventy-three per cent of Manitoba’s soils are deficient in phosphorus, which makes it second only to Saskatchewan for having the highest rate of deficient soils in North America.
The report from the Winnipegbased IISD suggests both the fertility and pollution problem could be reduced by capturing the valuable resource rather than flushing it into rivers and lakes.
The report says the looming reality of “Peak Phosphorus,” when consumption exceeds the capacity of dwindling reserves, requires a wholesale shift in how the nutrient is viewed across all sectors of society.
An essential nutrient for plant growth, global consumption has grown steadily since the early 1960s from 28 million tonnes to 160 million tonnes.
The cost has been rising too. In recent years, price shocks pushed the cost of the nutrient to $1,200 per tonne in 2008, up from $200 a tonne in 2002. Although prices have since fallen to around $850 per tonne, they are unlikely to drop to levels of the past.
While Canada prides itself on being a resource-rich nation, it is not well endowed with phosphorus reserves, a reality that threatens its status as an export agricultural powerhouse, and even a food-secure nation.
Canada is not only dependent upon importing the resource, its economy is currently driven by exporting it in the form of food.
“Current practice in many industrialized countries is unsustainable in peak phosphorus scenarios,” the report says. “Changes must include substantial shifts in production and consumption patterns.”
The report’s authors, Voora, Andrea Ulrich and Diane Malley, are calling for a broadly based reassessment of current policies and management strategies to prepare for phosphorus deficiencies. “An economic evaluation of the vulnerability of agriculture confronted with declining phosphorus availability could accelerate this process.”
“The responsibility for developing a phosphorus-secure future cannot be solely imposed on agriculture,” the report says. “Regulatory approaches such as proposed application thresholds can only do so much to optimize phosphorus management.”
The report notes that although modern agricultural methods and production practices are a contributor to phosphorus loading in waterways, they are in response to demands of industry, policy and society.
“They frame the system within which agriculture operates,” it says. “Responsibility must be shared by all stakeholders. This amounts to adopting a life cycle, cradle-to-grave approach to phosphorus-based products, which include fertilizers, food and fibre.”
Once phosphorus is lost to the sea, it takes millions of years for it to be mineralized back into a form that can be mined, the report says.