Final answer:
In response to the importance of agriculture in the Yangzi River valley, indigenous people developed advanced irrigation systems and practiced terrace farming, which allowed for more efficient land use and increased food production.
Step-by-step explanation:
As agriculture became increasingly important in the Yangzi River valley of southern China, the indigenous people responded through various forms of agricultural innovation and adaptation.
One such response included the development of advanced irrigation systems that turned unused hillsides into arable land. Additionally, they practiced terrace farming on hillsides, as evidenced by archeological discoveries similar to those of the Banaue Rice Terraces, which allowed them to create flat, submerged fields suitable for rice cultivation in mountainous regions. These adaptations allowed for an increase in food production and contributed to the growth of Chinese civilization.
While the Song dynasty focused on internal economic development, aiding such advancements by stabilizing agricultural markets, promoting technological improvements, and maintaining irrigation systems. These innovations resulted in higher crop yields and a surplus of food, fueling an increase in population and the expansion of urban centers. It was a transformation from mere subsistence farming to a more prosperous and complex society.