Relating to energy, one of the coming issues we will need to solve is fertilizer supply. Modern agriculture heavily depends on natural gas (via Haber-Bosch) to juice yields alongside genetic engineering. This isn't great for long-term soil health either, we just haven't been doing it long enough to see the effects of soil depletion.
From the wikipedia:
> Scott then asserts that the reason why hunter-gatherer societies transformed into agro-pastoral societies was due to coercion by the state. He cites research on an archaeological site in Mesopotamia named Abu Hureyra. Scott concurs with other scholars in the field that "'[n]o hunter-gatherers occupying a productive locality with a range of wild foods able to provide for all seasons are likely to have started cultivating their caloric staples willingly.'"
https://en.wikipedia.org/wiki/Against_the_Grain:_A_Deep_Hist...
In the modern world, it also means that cities have lower ecological footprint. Moving people around is much more energy intensive than moving food. Makes more sense to do farming across the country and concentrate the produce onto a small place packed with people.
Not necessarily saying this is a great tradeoff for individuals (who wouldn't want a backyard with an apple tree?) but in a sense, the fact that we're picturing a backyard with an apple tree instead of backbreaking work in the rice paddies throughout summer is a testament to how brutally efficient the modern agriculture is.