Whenever a business lays off workers, the former make more money.
Let's say you run a tea production company and your production costs, which includes paying your workers, are higher than your earnings. As a consequence, you can not afford paying your employees and, inevitably, you have to fire them so that you have more money to keep running your company.
The fishing, trade, soil, and to expand there country's territory.
Answer:
the increased diversion of water for irrigation