Phytoavailability of biosolids phosphorus.
Efficient utilization of biosolids P for agronomic purposes requires accounting for differences in the phytoavailability of P in various biosolids. Greenhouse studies were conducted with a common pasture grass grown in two P-deficient soils amended with 12 biosolids and a commercial fertilizer (triple superphosphate, TSP) to quantify P uptake and to assess the relative phytoavailabilities of the P sources. Biosolids were grouped into three general categories of phytoavailability relative to TSP: high (> 75% of TSP), moderate (25-75% of TSP), and low (< 25% of TSP). Two biosolids, produced via biological phosphorus removal (BPR) processes, were in the high category, and mimicked fertilizer P with regard to P phytoavailability. Most biosolids produced by conventional wastewater and solids digestion and additional treatments like composting were in the moderate category. Also included in this category was a BPR that had been pelletized and another BPR supplemented with Al. The low category included biosolids containing greater than normal (> 50 g kg(-1)) total Fe and Al concentrations and processed to high (> 60%) solids content.
O'Connor
G A
GA
Soil and Water Science Department, University of Florida, Gainesville, FL 32611, USA. gao@ufl.edu
Sarkar
D
D
Brinton
S R
SR
Elliott
H A
HA
Martin
F G
FG
D000383:Agriculture; D001682:Biological Availability; D005308:Fertilizers; D010758:Phosphorus / Q000493:pharmacokinetics*; D006109:Poaceae / Q000737:chemistry; D012037:Refuse Disposal
D005308:Fertilizers; D010758:Phosphorus