Potential application of Chlorella sp. biomass cultivated in landfill leachate as agricultural fertilizer

ABSTRACT

This study was to investigate the possibility of nutrient removal from landfill leachate using Chlorella sp. and its potential as agricultural fertilizer. Chlorella sp. was inoculated to a leachate suspension (1:1 ratio). Phosphate, ammonium and nitrate concentrations in the suspension and the dry cell weight of algae were measured at 0, 2, 4, 6 and 8 days of incubation. Then, the harvested microalgae biomass was mixed with a nutrient-poor soil at three levels: 0 (A0), 2 (A2) and 4 (A4) g 100 g⁻¹. The mixtures were incubated for 2 months, and soil biochemical properties, including soil organic carbon (OC), available phosphorus (P_ava), mineral nitrogen (N_min), microbial basal respiration (MBR) and microbial biomass carbon (MBC), were determined in soil at 7, 14, 28, 35, 42, 49 and 56 days of incubation. The dry cell weight of the microalgae increased over time and removed ammonium, phosphate and nitrate from the leachate by 98.7, 92.7 and 56.9%, respectively. The added microalgae biomass to soil caused positive and significant changes in soil OC, P_ava, N_min, MBR and MBC. Therefore, it seems that Chlorella sp. cultivated in landfill leachate can be used as an agricultural fertilizer in soil.

KEYWORDS:

• Ammonium
• microalgae
• organic carbon
• phosphate

Disclosure statement

No potential conflict of interest was reported by the author(s).