Tuesday, May 20, 2008

James Galloway on Nitrogen

This article has just been published by James Galloway and rings a loud alarm over the unheralded failure of the agricultural environment to sponge up all the soluble nitrogen that is been dumped on the land every year to maximize crop yield. This is not a new problem, but it is certainly an ignored problem.

I will make a brave conjecture however and that is that the application of biochar will halt this ongoing nitrogen leachate problem. The evidence available as well as prior work on zeolites conforms to this conjecture. The mere fact that terra preta retains fertility in a rainforest environment additionally supports this conjecture. What we lack is a good scientific work up that can be used by all proponents.

The reason that this mechanism works is the existence of solid crystalline acids throughout the biochar matrix caused by the heating process. These immobile acids grab mobile free ions such as nitrogen ions and other fertilizer ions and holds them until a living organism plucks them free.

That is why I am quite happy to have the commercial fertilizer industry produce powdered coked coal as a fertilizer media to deliver the nutrients to the soil. If every free fertilizer ion arrived in the soil bound to charcoal, then there would be little escapement of the fertilizer into the ground water.

I suspect that if we had a true understanding of soil nutrient dynamics, a carbon protocol would have been mandated decades ago.

The corollary of this conjecture is that the amount of applied fertilizer can be cut dramatically. Again we simply do not have the science worked up as yet. Perhaps we need to convince the fertilizer industry that they can make as much money shipping carbon as shipping fertilizer.

To be fair, the industry surely works to a price point based on a dollar price per treated acre. That will not change at all. The question is then about the costs of additives and fillers. Displacing ten percent of the filler with powdered coked coal is no trick at all. If that then leads to a fifty percent drop in the actual chemical percentage with the same agricultural result, we may even have a net drop in costs.

It would be a sweet irony if the advent of a proper carbon buffered fertilizer protocol succeeded in been more profitable than all previous protocols.


Public release date: 15-May-2008

Contact: James Galloway

Addressing the 'nitrogen cascade'

Papers in Science discuss incessant cycling of reactive nitrogen in environment

While human-caused global climate change has long been a concern for environmental scientists and is a well-known public policy issue, the problem of excessive reactive nitrogen in the environment is little-known beyond a growing circle of environmental scientists who study how the element cycles through the environment and negatively alters local and global ecosystems and potentially harms human health.

Two new papers by leading environmental scientists bring the problem to the forefront in the May 16 issue of the journal Science. The researchers discuss how food and energy production are causing reactive nitrogen to accumulate in soil, water, the atmosphere and coastal oceanic waters, contributing to the greenhouse effect, smog, haze, acid rain, coastal "dead zones" and stratospheric ozone depletion.

"The public does not yet know much about nitrogen, but in many ways it is as big an issue as carbon, and due to the interactions of nitrogen and carbon, makes the challenge of providing food and energy to the world's peoples without harming the global environment a tremendous challenge," said University of Virginia environmental sciences professor James Galloway, the lead author of one of the Science papers and a co-author on the other. "We are accumulating reactive nitrogen in the environment at alarming rates, and this may prove to be as serious as putting carbon dioxide in the atmosphere."

Galloway, the founding chair of the International Nitrogen Initiative, and a co-winner of the 2008 Tyler Prize for environmental science, is a longtime contributor to the growing understanding of how nitrogen cycles endlessly through the environment. In numerous studies over the years he has come to the realization of the "nitrogen cascade," and has created with his colleagues a flow chart demonstrating the pervasive and persistent effects of reactive nitrogen on Earth's environment (
www.initrogen.org).

In its inert form, nitrogen is harmless and abundant, making up 78 percent of the Earth's atmosphere. But in the past century, with the mass production of nitrogen-based fertilizers and the large-scale burning of fossil fuels, massive amounts of reactive nitrogen compounds, such as ammonia, have entered the environment.

"A unique and troublesome aspect of nitrogen is that a single atom released to the environment can cause a cascading sequence of events, resulting ultimately in harm to the natural balance of our ecosystems and to our very health," Galloway said.

A nitrogen atom that starts out as part of a smog-forming compound may be deposited in lakes and forests as nitric acid, which can kill fish and insects. Carried out to the coast, the same nitrogen atom may contribute to red tides and dead zones. Finally, the nitrogen will be put back into the atmosphere as part of the greenhouse gas nitrous oxide, which destroys atmospheric ozone.

Galloway and his colleagues suggest possible approaches to minimizing nitrogen use, such as optimizing its uptake by plants and animals, recovering and reusing nitrogen from manure and sewage, and decreasing nitrogen emissions from fossil fuel combustion.

"Nitrogen is needed to grow food," Galloway says, "but because of the inefficiencies of nitrogen uptake by plants and animals, only about 10 to 15 percent of reactive nitrogen ever enters a human mouth as food. The rest is lost to the environment and injected into the atmosphere by combustion.

"We must soon begin to manage nitrogen use in an integrated manner by decreasing our rate of creation of reactive nitrogen while continuing to produce enough food and energy to sustain a growing world population.”

Galloway's next effort is to create a "nitrogen footprint" calculator that people can access on the Internet, very similar to current "carbon footprint" calculators.

He says people can reduce their nitrogen footprints by reducing energy consumption at home, traveling less, and changing diet to locally grown vegetables (preferably organic) and fish and consuming less meat.

Galloway is quick to point out that along with the problems of excess reactive nitrogen in many areas of the world, there also are large regions, such as Africa, with too little nitrogen to grow enough food for rapidly growing populations. In those regions, the challenge is find ways to increase the availability of nitrogen while minimizing the negative environmental effects of too much nitrogen.

I copied this out of a post by Ron Larson. An industrial fertilizer should thus easily avoid almost any nitrogen losses.

“My knowledge on the relationship between nitrogen and biochar mostly comes from a visit to one nitrogen researcher in Australia last year (Dr. Lukas van Zweiten at IAI conference) who claims 80% reduction in nitrous oxide release in field trials with biochar (see towards end of

http://pubs.acs.org/subscribe/journals/esthag-w/2007/aug/tech/rr_biochar.html?sa_campaign=rss/cen_mag/estnews/2007-08-01/rr_biochar ).

Note that most nitrous oxide comes from agriculture, so 80% is potentially a big deal - and N2O is much worse than CO2 for climate impacts.”

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