What are the main food web roles played by nematodes, and how can we visually (with a microscope) distinguish among nematodes that play these roles? Through appropriate extractions and counting you...

What are the main food web roles played by nematodes, and how can we visually (with a microscope) distinguish among nematodes that play these roles?

Through appropriate extractions and counting you determine that there are 58 nematodes in a 1 g sample of soil. How many nematodes would occur in a 1.0 m²
area of this soil? In 1 hectare? Assume the samples came from the upper 10 cm of soil with a bulk density Mg/m³.