|Collins, Harold - Hal|
|KIMURA, E - Texas Agrilife Extension|
|FREAR, C - Washington State University|
|KRUGER, C - Washington State University|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2016
Publication Date: 9/8/2016
Publication URL: http://handle.nal.usda.gov/10113/63339
Citation: Collins, H.P., Kimura, E., Frear, C.S., Kruger, C.E. 2016. Phosphorus uptake by potato from fertilizers recovered from anaerobic digestion. Agronomy Journal. 108(5):2036-2049.
Interpretive Summary: The long-term sustainability of crop production systems depends, not only on balancing the physiological production requirements, but also on overcoming constraints to system productivity and profitability. The increasing price of fertilizers, along with high fuel costs, has caused financial hardship to many farmers and has stimulated an industry to develop fertilizers from localized agricultural waste streams. With the rising costs of fertilizers the use of these natural products, including nutrients recovered from dairy, cattle, swine and poultry operations is appealing. There is a significant opportunity in the Pacific Northwest (PNW) and across the U.S. to recover nutrients from animal wastes and use them as fertilizers without the need for composting. The recent use of anaerobic digesters (AD) on PNW dairies to mitigate environmental impacts from manure storage and produce energy can also produce substantial amounts of nutrient rich materials after digestion. Of the major plant nutrients, world resources of P are the smallest, and peak P is predicted to be reached globally by 2030. Because of potential shortfalls in P availability, P should be used as efficiently as possible in order to conserve the resource base and to maintain agricultural productivity. A variety of promising P-enriched products recovered from AD are now emerging as commercially viable. These include traditional products such as digested liquid manure and bio-solids from dairy anaerobic digesters and newer products such as recovered ammonium sulfate and P enriched fine solids from AD and ammonium and phosphorus containing struvite crystals from AD dairy operations. Our results indicate that all P fertilizer sources used, performed similarly to commercial available fertilizers when equal rates were applied and method of application was comparable.
Technical Abstract: Field experiments were conducted in the Columbia Basin of South Central Washington to assess the yield of potato (Solanum tuberosum) in response to application of phosphorus enriched materials recovered from anaerobic digestion of manure. The treatments were comprised of four rates (0, 56, 112 and 168 kg P2O5 ha-1) of P from five sources, three recovered from anaerobic digesters (AD); AD-dairy P-enriched fine solids (ADD); AD centrifuged poultry solids (ADP); and AD dairy derived struvite-P (ADS) compared to a commercial poultry fertilizer (PBP); commercial mono-ammonium phosphate (MAP) and a non-amended control (No-P). Over the two years of study, all P fertilizer treatments had higher total yields than the No-P treatment. Increasing the application rate of the P amendments did not affect tuber yield. Phosphorus P source and application rate of fertilizers had significant effects on petiole P concentrations. Incremental increases in petiole P concentrations averaged 300 – 500 mg kg-1 tissue with each application rate increase for MAP and ADS. However, there were only minor differences among increasing application rates for ADD, ADP, and PBP. Tuber yields among P fertilizers and rates of P application were not significantly different but were different between years and greater than the No-P treatment, averaging 2 Mg ha-1 and 10 Mg ha-1 fresh weight higher than the No-P treatment. The significant differences in yield between years also affected the tuber size distribution. Tuber size distribution in 2014 showed a significant shift from smaller tubers < 170 g to the 285+ g tuber classes. The P recovery efficiency averaged 42% among treatments recieving 56 kg P2O5 ha-1 and declined to 22% for higher rates of ADS, ADD, and MAP. Recoveries were lowest for the poultry derived materials (ADP, PBP), ranging 20 to 30%. Our results indicate that all P fertilizer sources used, performed similarly when equal rates were applied and method of application was comparable.