Why is active transport needed to take mineral ions into the cytoplasm of the root hair cell?

In plants, they need to move mineral ions from the soil into the roots. Mineral ions are more concentrated in the cytoplasm of plant cells than in soil water or dillute.

Explanation:

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.