HORTICULTURE

Detailed explanation-1: -Addition of common salt does not increase the fertility of the soil. It increases the salinity, which is not good for plant growth. Addition of water does not have any influence on soil fertility.

Detailed explanation-2: -The amounts of nutrients available in soils depend on interactions between: soil properties-pH, texture and different clay minerals can have an influence on soil fertility. soil biology-organisms living in the soil break down animal and plant matter into nutrient forms that can be used by plants.

Detailed explanation-3: -Manures are the inorganic substances which increase the fertility and water holding capacity of the soil.

Detailed explanation-4: -Overgrazing is the method which is not involved in soil conservation.