(i) State a main constituent of SOM.
A main constituent are decayed plant, non living organic
(ii) Explain with reference to the structure above, how SOM can increase the soil quality, in terms of the following
Provision of nutrients:
It contains amine, amino acid (COOH), it can be interchanged by ions of nutrients, ion exchange of nutrients can occur due to H (COOH)
It has OH.NH polar, as it can create hydrogen bonds with water molecules in the soil
(b) Discuss how irrigation can cause soil degradation
Irrigation contains sodium (Salt) when evaporation happens the salts stay, as there will be more build up in salt, which has an effect on plants. As they do not grow on soil that as high amount of salt, with irrigation, water can remove nutrients. (Ca^2+, K^+, etc).
(c) State the name of one source for each of the following organic soil pollutants.
Polyaromatic hydrocarbons (PAHs)
this link talks about the soil texture of the environment.