the population was increasing, the causes for population increase were there was food, Japanese people had shelters, there was agriculture destiny which meant a lot of farming but then epidemic had made everyone sick, this was the effect of the lack of fresh water. the water had some bacteria
the epidemic soon turned into a pandemic and then this made everyone else sick which then to led disease diffusion.
disease diffusion lead to many things to go down. negative growth started happening and with that the infant mortality rate was very and the fertility rate was going down.