Abstract:
Microalgal biomass is rich source of macro elements such as nitrogen, phosphorus, potassium, and calcium. The
purpose of this study was to investigate the different algae availability as fertilizer in agriculture. Therefore, three
different microalgaes were selected for the experiment. Chlorella spp., Neochloris conjuncta and Botryococcus braunii
cultures were grown in basal medium in the raceway which have the capacity of 1.5 tonnes. Experiment was ended
when the required value of the number of cell was reached. Microalgaes were harvested by a centrifuge in 6000 rpm.
Wet mass of microalgaes were dried in 65˚C at oven. Nitrogen, phosphorus, potassium, calcium, magnesium, iron,
manganese, zinc, copper, boron, and organic matter were measured. Nitrogen values for Chlorella spp, Botryococcus
braunii and Neochloris conjuncta microalgae were measured 5.45, 6.01, and 5.49 %, respectively. Microalgae can be
used as nitrogen sources for plant growth and development due to high nitrogen levels. The concentrations of potassium
were measured as 1.34, 0.94 and 1.05%. Organic matters were measured as 67.24, 64.15, and 64.65% for Chlorella spp,
Botryococcus braunii and Neochloris conjuncta, respectively. Chlorella strain is currently used for fertilization purpose.
However, this study showed that Neochloris conjuncta and Botryococcus braunii can used as fertilizer, as well.