Biosolids, Manure, and Micronutrients Robert Mullen & Nick Basta Nutrient Management/Soil Fertility Specialist Ohio State University February 21, 2008

Overview Essential micronutrients Deficiency/toxicity Biosolids/manure micronutrient content Micronutrient soil availability 11/15/2018 MWEA 2008

Essential Nutrients Thirteen essential nutrients Nitrogen, phosphorus, potassium, calcium, magnesium, sulfur (macros) Iron, manganese, boron, molybdenum, copper, zinc, and chlorine (micros) Nickel has recently been added Micros are needed in much lower concentrations to ensure adequate supply 11/15/2018 MWEA 2008

Plant concentration, mg/kg Essential Nutrients Necessary micronutrient concentrations for plant growth Nutrient Plant concentration, mg/kg Iron 50-200 Manganese 20 Boron 10-50 Chlorine 100 Zinc 20-50 Copper Molybdenum 0.1-0.2 11/15/2018 MWEA 2008

Essential Nutrients Micronutrients can be toxic when supplied at levels higher than plant nutrient need University of Hawaii 11/15/2018 MWEA 2008

Biosolids/Manures It stands to reason that human and animal waste contain the macro-/micronutrients needed for higher plant nutrition Everything we consume is plant based Thus, logically any animal waste material likely contains some level of micronutrient nutrition 11/15/2018 MWEA 2008

----------------mg/kg----------------- Biosolids/Manures Typical biosolid micronutrient content Nutrient Range Median Mean ----------------mg/kg----------------- Iron 1,000-153,000 11,000 13,000 Manganese 18-7,100 260 380 Boron 4-760 33 77 Zinc 101-27,800 1740 2790 Copper 84-10,400 850 1210 Molybdenum 5-39 30 28 Sommers (1997) – Journal of Environmental Quality 6:225-232. 11/15/2018 MWEA 2008

Biosolids/Manures Average animal manure micronutrient content of different animal sources Manure source Iron Manganese Boron Zinc Copper -----------------lb/wet ton--------------------- Dairy solid 0.5 0.06 0.01 0.03 Swine solid 19.0 1.09 0.04 0.79 0.50 Poultry 3.0 0.61 0.08 0.48 0.66 -----------------lb/1000 gal--------------------- Dairy liquid 0.9 0.11 0.12 Swine liquid 2.5 0.23 1.03 0.62 Micronutrient Status of Manure, University of Wisconsin, 2001 11/15/2018 MWEA 2008

Biosolids/Manures Biosolids/manures can be good sources of plant essential micronutrients Let’s calculate just how much we add based upon a single application rate 11/15/2018 MWEA 2008

Application rate (lb/acre) Biosolids/Manures Suppose we are applying 3 tons of biosolids per acre (dry basis), how much iron, manganese, boron, zinc, copper, and molybdenum have we supplied? Nutrient Application rate (lb/acre) Iron 78 Manganese 2.3 Boron 0.5 Zinc 16.8 Copper 7.3 Molybdenum 0.2 11/15/2018 MWEA 2008

Biosolids/Manure Do not assume that application will necessarily result in higher plant uptakes We have ample evidence that shows levels will increase if the nutrient was deficient But non-deficient sites will not necessarily show increases in crop uptake 11/15/2018 MWEA 2008

Biosolids/Manure Remember, biosolids/manure do not supply a salt form analogous to commercial forms Availability may not necessarily be comparable to commercial forms (at least short-term) Predicated on biosolid/manure application rate 11/15/2018 MWEA 2008

Biosolids/Manure Application rates and availability Long-term application of biosolids (13 years) on micronutrient availability (DTPA extractable) Study conducted at Oklahoma State University Biosolids application rate ranged from 3,500 – 10,000 lbs/acre (depending upon nitrogen analysis of material) 11/15/2018 MWEA 2008

Biosolids/Manure Total micronutrient analysis of soil PAN rate (kg/ha) Fe B Cu Zn -----------------mg/kg------------------ -----------------Biosolids------------------ 25.4 0.53 1.23 0.77 45 34.7 0.36 2.10 2.00 90 31.0 0.58 2.30 2.27 180 55.0 0.44 5.60 7.17 269 58.6 0.60 7.13 9.77 539 92.5 0.80 11.0 15.5 -----------Ammonium nitrate------------ 31.5 0.52 1.43 43.8 0.56 1.63 1.07 60.9 0.33 1.60 57.1 0.32 1.67 63.4 0.26 1.83 0.73 Schroeder et al. (2008) Soil Science Society of America Journal 72:73-82. 11/15/2018 MWEA 2008

Micronutrient Soil Availability Even though we may be supplementing micronutrient nutrition through biosolid/manure application their availability is dictated by soil pH More of a concern as it relates to toxicity from long-term application of biosolids/manures 11/15/2018 MWEA 2008

Micronutrient Availability 11/15/2018 MWEA 2008

Micronutrient Availability More acid soils have better (?) micronutrient availability (this goes for most of the heavy metals) Exception being molybdenum More acid soils also have greater risk of micronutrient toxicity (especially if the soil has a history of biosolids/manure applications) 11/15/2018 MWEA 2008

Micronutrient Availability To minimize risk of toxicity maintain soil pH in optimum range for crop production (6.0-7.0) Soils that have high soil pH levels are more likely to exhibit micronutrient deficiencies, thus application of biosolids/manure on these soils can be very beneficial 11/15/2018 MWEA 2008

Summary Biosolids/manure can be excellent sources of micronutrient nutrition for higher plants Soils with application histories can show higher micronutrient availability levels than those receiving commercial fertilization Maintaining adequate soil pH for crop production should ensure good micronutrient availability 11/15/2018 MWEA 2008

Questions?? Thanks! http://agcrops.osu.edu/fertility/ Robert W. Mullen Mullen.91@osu.edu 11/15/2018 MWEA 2008