Blue Green Algae hits ND again

[1bigfokker]

Tile drains. They're going to fuck up every lake and river. Just watch.

 

[Rowdie]

Where do you think fertilizer and chemicals are over applied? A farmers field or a lawn in town. Then ask yourself which would be more susceptible to run off of said chemicals and fertilizer.

That would be an interesting study. The amount of acres not considered in a town would dwarf acres in towns and cities. When compared to AG land, acres fertilized in towns is probably a lot lot less than you think. The amounts used per acre in towns would be much higher, but it would be interesting to compare the amounts sold and used in towns vs AG.

Just a guess but I'm betting AG dwarfs the town usage and run off.

 

[Bacon]

That would be an interesting study. The amount of acres not considered in a town would dwarf acres in towns and cities. When compared to AG land, acres fertilized in towns is probably a lot lot less than you think. The amounts used per acre in towns would be much higher, but it would be interesting to compare the amounts sold and used in towns vs AG.

Just a guess but I'm betting AG dwarfs the town usage and run off.

Of course ag uses more total tons but I can tell you we are not over applying fertilizer or chemical. The margins are way too tight.

 

[Bacon]

Tile drains. They're going to fuck up every lake and river. Just watch.

Not really if you understand how tile works. It’s buried 3 feet in the ground so the chemical and fertilizer has 3 feet of filtration before it runs out of the field. It would be way worse without tile than with in regards to chemical and fertilizer getting into lakes and rivers. And I’m not a huge fan of tile. We have non and couldn’t because of rocks and easements.

 

[Davy Crockett]

I read DL was bad today , does it get better in the fall or will it be the same till freeze up ?

 

[Allen]

Not really if you understand how tile works. It’s buried 3 feet in the ground so the chemical and fertilizer has 3 feet of filtration before it runs out of the field. It would be way worse without tile than with in regards to chemical and fertilizer getting into lakes and rivers. And I’m not a huge fan of tile. We have non and couldn’t because of rocks and easements.

I'm sorry that I didn't see this earlier, because the highlighted part is incorrect. Nitrogen in the fertilizer is generally in the NO3 (nitrate) form once dissolved in water and available to plants. I studied this fairly extensively for my Master's thesis and once it gets down to the water table as NO3, it doesn't last very long before our relatively young geologic materials react with organic carbon and pyrite in biologically mediated chemical reactions to remove the NO3 by converting it to N2 (nitrogen gas). By intercepting this fertilizer contaminated water prematurely through tile drains, it places that water back in a surface drain, which preserves the NO3 because it is thermodynamically second place more stable in an oxygenated environment.

In general, everywhere I looked at the water chemistry at the top of the water table, it was highly contaminated with NO3. It didn't/doesn't last long though in the water column as once the oxygen disappeared, the NO3 takes over as the most available and energetic oxidant while anaerobic bacteria become more and more prevalent with depth.

Basically, tile drains reduce the resident times for NO3 contaminated groundwater and prevent its full removal by our geologically young sediments in our aquifers. The primary components soils that contain enough organic carbon and pyrite to help remove the NO3. There are drawbacks to this though. One of the biggest heavy metal contaminants associated with the organic carbon and pyrite is arsenic. Hence, the chemical reactions also tend to increase heavy metal content of the groundwater. There are huge swaths of ND where arsenic is a major concern in drinking water wells.

At one time, ND investigated the potential for an arsenic based superfund site down in the Hankinson area. It was thought that poor storage and spills of grasshopper baits during the Dirty 30s were the source of the problem. As it turns out a mass balance of how much arsenic is contained in the groundwater vastly exceeds what was reasonably used as grasshopper poisons.

I too am not necessarily a big fan of tile drain use as we have developed over the past 30+ years, but am also of the opinion that it has a place in agriculture.

The bottom line is that through groundwater sampling, it's very easy to demonstrate ND farmers over apply nitrogen and phosphorus based fertilizers. Their saving's grace is that our soils are far more reactive being the sands are based off of sedimentary rocks, versus the primarily igneous rock derived sands and gravels of our communist neighbor to the east. That's why MN has much tighter controls on fertilizer application than ND. Farmers are shown by fertilizer salespeople their yield potential versus application rates of fertilizer. They are not shown how much escapes the root zone and makes it into the groundwater, because doing so would reduce the sales of fertilizer. Basically, if no fertilizer escaped the root zone, the plants would be nitrogen limited...and that means they would be leaving some production on the table. Balancing yield with lost nitrogen is something very few farmers do. While good business, they just don't have the skillset to really sharpen their pencils on this one. They would need to know exactly how much NO3 is getting to the water table, and that's a labor intensive and financially expensive thing to measure.