Prospects and constraints in studying the biodiversity of agriculturally important microalgae and cyanobacteria and useful statistical tools

Microalgal and cyanobacterial communities have a key role in sustaining the fertility of aquatic and terrestrial habitats. Thus, understanding the actual biodiversity of these communities is a task of utmost importance. However, this particular task suffers from several technical constraints and challenges. Sampling procedures and criteria for counting individuals of various microalgal and cyanobacterial species in such systems have not been standardized. Biodiversity indices are considered promising; however, ambiguity in respect of species concept and characterization criteria of microalgal and cyanobacterial forms makes the determination of biodiversity indices a complicated task. Recently, DNA barcoding was employed for the identification of microalgal and cyanobacterial species. However, it needs sufficient experimental validation. The functional diversity and zeta diversity, which are helpful in ecosystem process assessment, are largely unexplored for microalgal and cyanobacterial communities. Adequate knowledge of sampling designs, methods for detecting outliers and errors, and data transformation in biodiversity studies are crucial. Several analytical tools, such as analysis of variance (ANOVA), analysis of similarity (ANOSIM), multidimensional scaling (MDS) and cluster analysis are obligatory for understanding the compositional differences of different microbial communities. Regression and multiple correlations are important in realizing the relationships of different environmental factors. Principal component analysis (PCA) and canonical correspondence analysis (CCA) are effective in interpreting the influence of environmental factors on the distribution of microalgal and cyanobacterial species in a geographical region or a land patch. Nevertheless, statistical software packages are the backbone of research activities these days. So, development of new biodiversity software packages specific to microalgae and cyanobacteria is required.

Automated summary

Microalgal and cyanobacterial communities play a crucial role in maintaining the fertility of aquatic and terrestrial habitats. However, understanding the biodiversity of these communities faces technical constraints and challenges, such as standardized sampling procedures and criteria. DNA barcoding has been used for species identification, but it requires experimental validation. Functional and zeta diversity, important for ecosystem process assessment, are largely unexplored in these communities.