We return here to the longignored problem of fertilizer management and the phosphorus issue. We are saying here that phosphorous reservesare plausibly reaching their limits. Ifwe continue to use them as we have been, then that is true.
My counter to is that we are enteringthe age of soil reconstruction through application of biochar methods. In this protocol, one increases soil elementalcarbon content through application of biochar to the soil each season until thesoil content approaches ten percent.
The elemental carbon grabs allfree ions including nutrients such as phosphorous wherever it comes from andwhenever it is released. It retains themuntil a root arrives and extracts what it needs. Thus solution losses are ended.
Once a particular soil has optimizedits nutrient content, and we mean virtually any soil, then adding additionalnutrients should be a case of simply tilling the waste back in. The Amazon has reported such soils producingheavily for sixty years without any fertilizers in tropical conditions.
Present practice is anomalous andunsustainable and generally toxic somewhere or the other. The practice of biochar promises to make allsoils rich and sweet, while also eliminating ‘patchiness’
World phosphorous use crosses critical threshold
February 14, 2011 by Terry Devitt
(PhysOrg.com) -- Recalculating the global use of phosphorous, afertilizer linchpin of modern agriculture, a team of researchers warns that theworld's stocks may soon be in short supply and that overuse in theindustrialized world has become a leading cause of the pollution of lakes,rivers and streams.
Writing in the Feb. 14 edition of the journal EnvironmentalResearch Letters, Stephen Carpenter of the University of Wisconsin-Madison andElena Bennett of McGill University report that the human use of phosphorous, primarily inthe industrialized world, is causing the widespread eutrophication of freshsurface water. What's more, the minable global stocks of phosphorous areconcentrated in just a few countries and are in decline, posing the risk ofglobal shortages within the next 20 years.
"There is a finite amount of phosphorous in the world,"says Carpenter, a UW-Madison professor of limnology and one of the world'sleading authorities on lakes and streams. "This is a material that'sbecoming more rare and we need to use it more efficiently."
Phosphorous is an essential element for life. Living organisms,including humans, have small amounts and the element is crucial for driving theenergetic processes of cells. In agriculture, phosphorous mined from ancientmarine deposits is widely used to boost crop yields. The elementalso has other industrial uses.
But excess phosphorous from fertilizer that washes from farm fieldsand suburban lawns into lakes and streams is the primary cause of the algaeblooms that throw freshwater ecosystems out of kilter and degrade water quality.Phosphorous pollution poses a risk to fish and other aquatic life as wellas to the animals and humans who depend on clean fresh water. In someinstances, excess phosphorous sparks blooms of toxic algae, which pose adirect threat to human and animal life.
"If you have too much phosphorous, you get eutrophication,"explains Carpenter of the cycle of excessive plant and algae growth thatsignificantly degrades bodies of fresh water. "Phosphorous stimulates thegrowth of algae and weeds near shore and some of the algae can containcyanobacteria, which are toxic. You lose fish. You lose water quality fordrinking."
The fertilizer-fueled algae blooms themselvesamplify the problem as the algae die and release accumulated phosphorous backinto the water.
Carpenter and Bennett write in their Environmental Research Lettersreport that the "planetary boundary for freshwater eutrophication has beencrossed while potential boundaries for ocean anoxic events and depletion ofphosphate rock reserves loom in the future."
Complicating the problem, says Carpenter, is the fact that excessphosphorous in the environment is a problem primarily in the industrialized world,mainly Europe, North America and parts of Asia. In other parts of the world,notably Africa and Australia North America , where fertilizerswith phosphorous are most commonly applied, are already loaded with theelement.
"Some soils have plenty of phosphorous, and some soils do not andyou need to add phosphorous to grow crops on them," Carpenter notes."It's this patchiness that makes the problem tricky."
Bennett and Carpenter argue that agricultural practices to betterconserve phosphate within agricultural ecosystems are necessary to avert thewidespread pollution of surface waters. Phosphorous from parts of the worldwhere the element is abundant, they say, can be moved to phosphorous deficientregions of the world by extracting phosphorous from manure, for example, usingmanure digesters.
Deposits of phosphate, the form of the element that is mined foragriculture and other purposes, take many millions of years to form. Thenations with the largest reserves of the element are the United States , China and Morocco
World Phosphorus Use Crosses Critical Threshold
by Staff Writers
Recalculating the global use of phosphorus, a fertilizer linchpin of modernagriculture, a team of researchers warns that the world's stocks may soon be inshort supply and that overuse in the industrialized world has become a leadingcause of the pollution oflakes, rivers and streams.
Writing in the Feb. 14 edition of the journal Environmental ResearchLetters, Stephen Carpenter of the University of Wisconsin-Madison and ElenaBennett of McGill University report that the human use of phosphorus, primarilyin the industrialized world, is causing the widespread eutrophication of freshsurface water. What's more, the minable global stocks of phosphorus areconcentrated in just a few countries and are in decline, posing the risk ofglobal shortages within the next 20 years.
"There is a finite amount of phosphorus in the world," saysCarpenter, a UW-Madison professor of limnology and one of the world's leadingauthorities on lakes and streams. "This is a material that's becoming morerare and we need to use it more efficiently."
Phosphorus is an essential element for life. Living organisms,including humans, have small amounts and the element is crucial for driving theenergetic processes of cells. In agriculture, phosphorus mined from ancientmarine deposits is widely used to boost crop yields. The element also has otherindustrial uses.
But excess phosphorus from fertilizer that washes from farmfields and suburban lawns into lakes and streams is the primary cause of thealgae blooms that throw freshwater ecosystems out of kilter and degrade waterquality. Phosphorus pollution poses a risk to fish and other aquatic life aswell as to the animals and humans who depend on clean fresh water. In someinstances, excess phosphorus sparks blooms of toxic algae,which pose a direct threat to human and animal life.
"If you have too much phosphorus, you get eutrophication,"explains Carpenter of the cycle of excessive plant and algae growth thatsignificantly degrades bodies of fresh water. "Phosphorus stimulates thegrowth of algae and weeds near shore and some of the algae can containcyanobacteria, which are toxic. You lose fish. You lose water quality fordrinking."
The fertilizer-fueled algae blooms themselves amplify the problem asthe algae die and release accumulated phosphorus back into the water.
Carpenter and Bennett write in their Environmental ResearchLetters report that the "planetary boundary for freshwater eutrophicationhas been crossed while potential boundaries for ocean anoxic events anddepletion of phosphate rock reserves loom in the future."
Complicating the problem, says Carpenter, is the fact that excessphosphorus in the environment is a problem primarily in the industrializedworld, mainly Europe, North America and parts of Asia. In other parts of theworld, notably Africa and Australia North America , where fertilizerswith phosphorus are most commonly applied, are already loaded with the element.
"Some soils have plenty of phosphorus, and some soils do not andyou need to add phosphorus to grow crops on them," Carpenter notes."It's this patchiness that makes the problem tricky."
Bennett and Carpenter argue that agricultural practicesto better conserve phosphate within agricultural ecosystems are necessary toavert the widespread pollution of surface waters. Phosphorus from parts of theworld where the element is abundant, they say, can be moved to phosphorusdeficient regions of the world by extracting phosphorus from manure, forexample, using manure digesters.
Deposits of phosphate, the form of the element that is mined foragriculture and other purposes, take many millions of years to form. Thenations with the largest reserves of the element are the United States , China and Morocco
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