A bright fresh form of ammonium phosphate plant food has been field - tested by University of Illinois Urbana - Champaign researchers . The fertilizer , struvite , tender a triple win for sustainability and crop production , as it recycles nutrients from effluent stream , reduces percolate of phosphorus and atomic number 7 in agricultural soils , and maintains or improves soybean yield compared to schematic phosphorus fertilizer .
" There have been some research lab and glasshouse labor show the potential of struvite , but this is the first landing field - scale of measurement judgment of alimentary loss and grant benefits together , " say principal investigator Andrew Margenot , associate professor and faculty Extension specialist in the Department of Crop Sciences , part of the College of Agricultural , Consumer and Environmental Sciences ( ACES ) at U. of I. " We observe that struvite can be a full substitute for monoammonium inorganic phosphate ( MAP ) or diammonium inorganic phosphate ( DAP ) for soybeans yield - wise , and it reduces nonpoint origin nutrient losses comparative to conventional fertilizer choice . "
His team ’s results are put out in the Journal of Environmental Quality .
Applying MAP or DAP in the fall as a germ of phosphorus for crop is common pattern for corn and soy output in much of the Midwest . But , because the Lucifer in MAP and DAP is highly water system soluble , much of the nutrient is lost during the ensuing winter and early spring months . Not only can this contribute to downstream nutritive contamination , but it also means there may be less P uncommitted in the soil by the time crop are implant in bound .
Importantly , MAP and DAP also curb soluble forms of N , an overlooked fact that Margenot read is contributing to the problem of nitrate expiration across the Midwest .
" There is a major blind blot in the nitrogen cycle , " Margenot said . " In the U.S. and the Midwest specifically , the overwhelming majority of our P fertilizers are ammoniate . When farmers grease one’s palms a atomic number 15 root to apply in the downslope , their options are generally limited to MAP or DAP , so they ca n’t avoid co - applying nitrogen . "
He did the math in a associate paper and incur DAP applied at the distinctive charge per unit ( 200 pounds per Akka ) adds 36 pounds of nitrogen per acre that most farmers — and Edwin Herbert Land Duncan Grant passport — do n’t describe for . bestow it up across Illinois , Margenot forecast that 198 million quid of nitrogen are supply every declination in the form of MAP or DAP .
" That identification number is 11 % more than our statewide nitrate loss reduction target of 178 million pounds , " he said . " Managing this unmarked fall - lend oneself nitrogen is low - hanging fruit that could make a large dent in nitrate loss in Illinois and other Mississippi River Basin states , and we could do it without interchange phosphorus covering rate . "
Struvite also contains nitrogen , but struvite is less water soluble than MAP . That explains why Margenot ’s team receive phosphorus and nitrogen leaching were importantly lower under struvite than MAP , corresponding to instinctive leach measured in unimpregnated soils .
But if the food are less soluble , does that mean plants have a hard prison term get at them ? Not concord to the Journal of Environmental Quality subject . Soybean output were n’t importantly unlike under either fertiliser . And in the study ’s southern Illinois site , struvite — but not MAP — actually increase soybean fruit compare to no - fertilizer ascendence secret plan . Margenot thinks the payoff bump could have ensue from the magnesium in struvite .
Struvite ( atomic number 12 ammonium phosphate , a 5 - 22 - 0 [ 10 Mg ] reservoir ) forms when magnesium is add to effluent , where it react with phosphorus and atomic number 7 and pull those nutrients out of the waste current . Chicago and St. Louis have leased portions of their sewer water stream to a ship’s company to manufacture the recycled plant food , but Margenot allege the struvite manufacturing industry is currently too small to satisfy the Lucifer needs of the entire Corn Belt .
" Struvite is n’t scalable right now , but we ’re prove the efficacy of a root that will be on the shelf one day . Our results point to the benefits of scaling up struvite product and use on the farm , " he say .
Although struvite decreased nourishing red ink relative to MAP , Margenot note that nutrient passing find even without added fertilizer , and recommends hatch crop to mitigate these " ground " losses that fall out regardless of fertilization .
" When we added no plant food , be it MAP or struvite , we still ascertain substantial exit , especially in the higher constitutional affair Mollisols [ black prairie ground ] of our Central Illinois site , " he enjoin . " Our soils are so productive ; they hold a lot of organic nitrogen and morning star . If it ’s affectionate enough , these food will mineralize and become nitrate and phosphate . If there ’s no crop there to grab it , like a cover crop or wheat , then those nutrient will be leached . "
rootage : aces.illinois.edu
