Soil algae: A case study of two vegetable farmlands in Lagos and Ogun states, southwest Nigeria

Abstract

Microalgae occur in nearly all terrestrial environments and are invariably encountered both on soil surface and beneath. Also, the importance of algae in soil  formation and soil fertility improvement cannot be over emphasized as the world is working towards food security. Based on this, top soil samples (0-15cm) were collected fortnightly for seven months (October 2012- April 2013) from two different vegetable farms and analyzed for abiotic parameters and algae composition. These vegetables farms were characterized by the same soil types and fertilizers used but differ in their land use history. Four classes of algae were identified, Chlorophyceae, Cyanophyceae, Bacillariophyceae and Euglenophyceae. Higher total organic matter value (6.60%) and more euglenoids were recorded at James farm as compared to Iyana-Iba farm probably due to the pig sty around it. The presence of nitrogen fixing microalgae (Nostoc azollae) in the top soil of both  vegetable farms further establishes the role of blue green algae in soil nutrients for plant growth.

Key words- Soil Fertility, Soil algae, Farmland, Nitrogen fixation, Vegetables