Answer:
It reduced the amount of farmable land.
It led to the development of new forms of irrigation.
It caused people to change the types of crops they planted.
Shrinking farms were unable to support large cities.
Step-by-step explanation:
As you may already know the establishment and maintenance of populations in the most varied regions, it depends a lot on the success of agriculture. Agriculture, in turn, is only effective when the region has adequate environmental resources for the growth of crops. Generally, these resources are associated with the presence of water, fertile soil and a hot, humid climate.
However, regions like the Vale do Rio Indo often lacked some resources, such as the weather for example. The Indo River valley had a cold and dry climate, which made it impossible to establish easy and powerful agriculture, but it was possible to adapt to that climate and still produce. In the case of the population in the valley of the river going, it was necessary to create alternative irrigation methods to adapt to the lack of rainwater, it was also necessary to plant crops that were better adapted to this climate. In addition, it was necessary to reduce agricultural land.