A perspective on the current status of approaches for early detection of microalgal grazing
- PDF / 340,776 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 66 Downloads / 161 Views
A perspective on the current status of approaches for early detection of microalgal grazing Pranali Deore 1,2,3 & John Beardall 2 & Santosh Noronha 3 Received: 19 June 2020 / Revised and accepted: 18 August 2020 # Springer Nature B.V. 2020
Abstract Consumption of microalgae, as prey, by predatory zooplankton is a major ecological process in aquatic environments. The presence of predators in large-scale cultivation, such as in open ponds, results in a devastating loss of microalgal biomass, often referred to as a “pond crash.” Reported biomass losses of 20–30% due to predator invasion in open cultivation systems is one of the bottlenecks in achieving a desired economically viable system. Many commercial scale algal cultivation setups have reported clearance of prey within 2–5 days after detection of predators. Knowledge of how to monitor and manage algal pests is limited. Research to date is largely driven towards the development of predator mitigation strategies, whereas monitoring is mainly limited to traditional (direct) methods such as microscopy- and oligonucleotide-based screening. Use of online and real-time measures for in situ estimation of microalgal grazing is sparsely reported. We suggest that more knowledge about microalgal grazing at the pond level is required for the development of indirect screening measures, based on unique features of microalgal prey and predator interactions, to enable online monitoring. This article systematically reviews the current status of available methods, both at laboratory and field level, for early detection of microalgal grazing. Keywords Pond crash . Early detection . Algal pest monitoring . On-line methods . Microalgal predators
Introduction Microalgae have emerged as one of the most desirable clean feedstocks due to their ability to produced versatile commodity products while adapting to climate change. Commercial microalgae cultivation is estimated to be capable of fixing 513 t of carbon dioxide and producing up to 120 t of dry biomass per hectare annually (Bilanovic et al. 2009). However, the production costs of microalgal biomass are at least fivefold higher than those of plant-based feedstock. The desirable yield of microalgal biomass for economically feasible cultivation in open ponds (for biofuels) has been estimated to be 25 g m−2 day−1 to be produced at the projected minimum biomass selling price (MBSP) 330–385 US$ per tonne (Davis et al. 2016). Both productivity and MBSP are, however, * Santosh Noronha [email protected] 1
IITB-Monash Research Academy, Mumbai 400076, India
2
School of Biological Sciences, Monash University, Clayton 3800, Australia
3
Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
mainly dependent on the type of cultivation setup. Closed photobioreactors and open raceway ponds are widely used for large-scale microalgal cultivation. Closed photobioreactor cultivation favors higher productivity, albeit at higher cost (Borowitzka 1999), due to increased capital and operational expenditures
Data Loading...
