Soil Algae in field and forest environments [Hutcheson Memorial Forest, New Jersey]

The prokaryotic and eukaryotic algal components of soil were quantified and identified generically over a 17-mo period in 2 successional fields and a climax forest. A correlation of the quantitative and qualitative changes was sought with other biological components (bacteria, actinomycetes and fungi) and major chemical and physical parameters. The highest counts obtained for the eukaryotic algae were 3.3 x 10^7, 2.2 x 10^7, and 1.2 x 10^5 cells/g soil for a 1-yr old field, an 11-yr old field and the forest, respectively. The highest counts obtained for the prokaryotic (bluegreen) algae were 8.2 x 10^5, 2.3 x 10^5 and 1.6 x 10^4 cells/g soil for the same sites. The total number of algae in all 3 sites declined during the summer. There was no further decline in winter. The greatest number algal genera was found in the 1-yr old field, 28 of a total 35 isolated or 80%; fewer were observed in the 11-yr old field and the forest, 57% and 63%, respectively. A predictive model for numbers of soil algae was formed by multiple regression analysis. The significant factors that showed a relationship with the bluegreen algae were pH, time, Mg, precipitation and the eukaryotic algae, R^2 = 45%; significant factors with the eukaryotic algae were time, Mg and the bluegreen algae, R^2 = 37%. Prediction equations were tested against additional data with success.