Seven Years of Biosolids versus Inorganic Nitrogen Applications to Tall Fescue

Abstract

Repeated applications of municipal wastewater biosolids is cost effective for biosolids managers, but may lead to undesirable accumulations of nutrients or contaminants. We evaluated the effects of seven years of biosolids applications on tall fescue (Festuca arundinacea Schreb.) production and nutrient availability. We compared two types of Class A biosolids applied to tall fescue on a sandy loam in western Washington. Mean annual biosolids rates of 290, 580, and 870 kg total N ha(-1) yr(-1) were compared with inorganic N and zero-N controls using a randomized complete block design. We measured yield and N uptake for each forage harvest, plant tissue metals at selected harvests, soil nitrate each fall, diethylenetriaminepentaacetic acid (DTPA)-extractable metals after five years of applications, and soil pH, available P, and organic C after seven years. Forage yields increased with biosolids rate. Apparent nitrogen recovery (ANR) for biosolids averaged 18% in 1993 (Year 1), 35% in 1994, and 46% in 1999. The ANR for inorganic N averaged 62% from 1994-1999. Residual soil nitrate was less than 25 kg ha(-1) for all treatments through 1995, but increased beginning in 1996 for the high biosolids rate. Biosolids increased soil organic C levels by 2 to 5 g kg(-1) and Bray-1 P levels by 300 to 600 mg kg(-1) (0-15 cm depth). Plant tissue Zn increased from 24 to 66 mg kg(-1) at the highest application rate. Nearly all of the DTPA-extractable metals remained in the 0- to 8-cm soil depth.

Effect of poultry litter on silage maize (Zea mays L.) production and nutrient uptake

“…The AENR represents the fraction of N-fertilizer recovered in the harvested part of the plant; the unrecovered N fraction is in the unharvested parts, and the remainder becomes part of the soil biomass or is lost to leaching (Thomsen et al, 1997;Cogger et al, 2001). In this work, the AENR was used to provide an indirect assessment of the amount of plant-available N supplied by the mineral fertilizer and PL.…”

“…This suggest that the N released from PL is an appropriate N supply for silage maize under the conditions in which the crop was grown. In addition, the N from PL becomes available for plant uptake over a long period following its application; this slow release minimizes the potential leaching of NO 3 -N (Cogger et al, 2001;Rees and Castle, 2002).…”

Determination of the Efficiency of Treated Sludge as a Fertilizer

“…The nitrogen concentration in the ST5 plot was the highest at 137.5 mg/L due to theapplication of both treated sludge and chemical fertilizer, had reduced the NUE of the plant and grass yield compared to all the other treatments. Cogger et al (2001) reported that the fertilizer value of sludge was comparable to that of chemical fertilizers because the grain and silage yield of corn obtained for both treatments was not significantly different.…”

Sediment, Nutrient, and Bacterial Runoff from Biosolids and Mineral Fertilizer Applied to a Mixed Cool- and Native Warm-Season Grassland in the Ozark Mountains

“…Among the benefits, biosolids provide recycled nutrients to soils and can serve as an alternative or a substitute to costly mineral fertilizers (MF). In addition to providing nutrients, biosolids provide organic matter to soil [4,5], increase infiltration [6], potentially improve soil quality [5,7,8], and increase agronomic productivity [5,7,[9][10][11][12]. Using biosolids as a substitute for MF also helps reduce energy use which would have been associated with production and transportation of MF.…”