There are even weirder systemic effects that happen.
There has been a longstanding, drastic decline in seabird numbers, along with a decline in the upper trophic levels in the ocean, for the last fifty years or so. A few years back, it was determined that at least in the case of seabirds, the limiting factor for their populations appeared to be B-vitamin deficiency of all things—large numbers of birds were dying of it. What could be suddenly causing that was a mystery, with all sorts of dire ideas thrown about regarding collapses in ocean productivity or zooplankton populations.
Turns out that the most likely reason for it is actually nitrogen fertilizer pollution. The algae that bloom in the ocean dead zones where fertilizer runoff hits it turn out to be largely B-vitamin auxotrophs—they cannot make it and take it up from the local ecosystem. And then when the algae bloom dies and the water goes anoxic, they sink to the ocean floor and are buried with the B vitamins they took up, efficiently sucking it out of the ecosystem and burying it in the seafloor.
There are even weirder systemic effects that happen.
There has been a longstanding, drastic decline in seabird numbers, along with a decline in the upper trophic levels in the ocean, for the last fifty years or so. A few years back, it was determined that at least in the case of seabirds, the limiting factor for their populations appeared to be B-vitamin deficiency of all things—large numbers of birds were dying of it. What could be suddenly causing that was a mystery, with all sorts of dire ideas thrown about regarding collapses in ocean productivity or zooplankton populations.
Turns out that the most likely reason for it is actually nitrogen fertilizer pollution. The algae that bloom in the ocean dead zones where fertilizer runoff hits it turn out to be largely B-vitamin auxotrophs—they cannot make it and take it up from the local ecosystem. And then when the algae bloom dies and the water goes anoxic, they sink to the ocean floor and are buried with the B vitamins they took up, efficiently sucking it out of the ecosystem and burying it in the seafloor.
These systems react in strange, nonlinear ways...