Question

Why are modern farming techniques and a reduction of biodiversity a problem?

Answer 1

Modern farming techniques emphasize a sort of factory mentality; meaning usually only one type of crop is grown (low biodiversity), accompanied with high fertilizer/pesticide usage. Fertilizer and nitrates in it easily washes into bodies of water and can result in eutrophication, and possibly infect public water supplies and groundwater systems.

Biodiversity is important because organisms in their environments are like bricks in a tower - taking out one can be threatening because so many others may depend on it as a source of food/symbiosis/etc. And a world without diversity is boring, asides.

Hope that helps.