The factor which decides the type of soil is:

$(a)$ How is soil pollution caused?
$(b)$ Write three ways to prevent soil pollution.

Why is step farming common in hills?

$A$ teacher mentioned organisms that enrich the soil with nutrients. Rahila was curious to know more about them. She searched the internet and learned about $Rhizobium$ bacteria and cyanobacteria.
$(i)$ What are bio-fertilizers?
$(ii)$ Explain how any one of the organisms mentioned above enriches the soil with nutrients.
$(iii)$ Why was Rahila curious to get more information?

Which symbiotic life forms can grow on stones and help in the formation of soil? Write the mode of their action for making soil from rocks.

On what factors do the mineral nutrients that are found in a particular soil depend?