[Terrapreta] Nitrate Threatening the Nation's Watersheds

[David Hirst .com]

Science has a short article on the risks to water quality from nitrates. Extract below.
They also reference a Nitrate Primer by the EPA, which looks useful and helpful.

My understanding is that a lot of the nitrate problem is due to "artificial" fertiliser,
although some is due to the combining of oxygen and nitrogen that occurs in combustion,
particularly of fossil fuels.

I also understand that there is a path from excess nitrates to addition NO (and N2O?),
and that NO is a very potent greenhouse gas.

However, I also understand that Tera Preta and / or BioChar is very effective in binding
nitrates in the soil, so reducing leaching and the nitrate water and eutrophication
problem. And that this substantially reduces NO also.

So there do seem to be several benefits of value to society from the Biochar and TP:

1.	Carbon is captured from the atmosphere and sequestered in a safe form for a long
time - half life well in excess of 500 years?
2.	Soil fertility and so food (or biofuel) value is enhanced
3.	Nitrate pollution of water sources is reduced
4.	NO is reduced, so avoiding GHG effects

Clearly different practises in different places will have different balances among these
(and perhaps others), and the values may change over time.

So the challenge seems to be to ensure that each of these brings a revenue stream to the
people on the land and making the biochar and TP, and the combined revenue stream should
provide "right livelihoods" to a large number of people. At times, one feels that this is
only distantly related to the "profitability" sought for by corporates, and that
governments will have to play a significant role in making the relationship closer.

At present, there are very limited markets in all these value chains. All our trading
systems are geared to emissions reductions - not making the problem worse - and few
reward active contributions to solving the problems.

So quite a challenge.

Cheers

David

 

http://sciencenow.sciencemag.org/cgi/content/full/2008/312/2?etoc


Nitrate Threatening the Nation's Watersheds


By Phil Berardelli
ScienceNOW Daily News
12 March 2008

There's mixed news about how the country's streams and rivers are handling increased
loads of nitrate from human activities. The ecosystems are normally highly tolerant of
the chemical, which is good. But new research shows that nitrate absorption can reach a
limit, and that's what is happening in many areas. Worse, the budding biofuels industry
figures to release even more nitrate into watersheds in the coming years.

..

 

http://www.epa.gov/OGWDW/contaminants/dw_contamfs/nitrates.html

 

David Hirst

Mobile:  +44 7831 405443

Direct:   +44 1273 570113

email:     <mailto:david at davidhirst.com> david at davidhirst.com

 

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