2.3.23 (HL)—Haber process

The Haber process makes ammonia from nitrogen and hydrogen, increasing plant-available nitrogen but carrying energy and pollution costs.

Fertilizer can raise yields where nitrogen limits growth. Energy use and excess application can add emissions, leaching, runoff and eutrophication, so evaluate the whole balance.

Applying 100 kg N raises yield only if crop uptake increases; the unused fraction can leave the field and harm water quality.

No. Include production energy, nitrogen-use efficiency and downstream losses.

‘Synthetic’ is not the same as ‘always harmful’; judge dose, efficiency, source energy and receiving ecosystem.