[T]he problem of fertility in agriculture is deeply unnatural. Nature has inspired many good ideas, like crop rotations and recycling of nutrients [and] these practices, along with reductions in food waste and meat consumption, will be imporant parts of efforts to mitigate the “growing pollution web.” That said, nature does not take an interest in the well-being of humankind, so it seems unwise to expect it to solve the problems that we have created for ourselves. Too much synthetic nitrogen fertilizer causes problems, but that doesn’t mean the solution is to use none at all.

—An unlikely fix: nitrogen fertilizer and organic agriculture - Inexact Change