Question

(f) Soil erosion.
(vi) Formation of soil
(g) Frozen fresh water (vii) CFCS
(h) Oxides of nitrogen (viii) Ice caps at poles
(i) Nitrogen fixing bacteria
(ix) Deforestation
Short questions (2x3=6)
Q1.Fertile soil has lots of humus Why?
Q2.There is mass mortality of fishes in a pond. What may b​

Answer 1

Answer:

1 Ans

Fertile soil has lots of humus because it contains microorganisms that decompose dead organic matter present in soil and help in the formation of humus. Humus is a sources of mineral, absorbs water and makes the soil porous for easy passage of plant roots

Explanation:

2ans.

There may be several reasons for the mass mortality of fishes in a pond: Domestic sewage − It mainly contains organic matter, which is biodegradable. Microorganisms involved in theirdegradation consume a lot of oxygen and the BOD of the water body increases leading to the death offishes