The supplemental stores of food and nutrition that you brought with you to Irata begins to run out and you need to produce more local food to offset the decreased nutritional supplements that you brought from home.
Same thing when people were originally "colonizing" the New World....settlers would use up their stores of food that they had brought with them and then they would require a greater output from local sources to survive and thrive.
Also, as the size of each person's holdings increase, they would need an increase in the food energy required to work all of their plots - which may be a way to slightly alter the food requirements curve....less plots, less energy needed to work them so then perhaps a player with 7 plots would only need 3 food while a person with 9 may need 4 or 5 as they willl utilize more nutritional energy in order to complete the increased work load of the extra plots.....
As always, it is great fun when the community develops these "stories" ie - Where Do the Freed Mules GO? and I look forward to reading many possible answers to this question.
PS - data2008 - being laid up for a little while, you should have LOTS of time to think up the answers.
Hope you are out soon
