PHOTO: Phil Roeder, Flickr CC
Northern Minnesota is no stranger to cattails. These common reeds grow seed pods that look like corn dogs, but are, in fact, filled with downy fluff. (You only make that mistake once). In fact, during World War II Northern Minnesotans earned money harvesting cattails to replace cotton in pillows, furniture, life vests, seat cushions and more.
But one scientific study warns that too many cattails could create a dangerous self-fulfilling prophecy when it comes to global climate change.
Phenologists like John Latimer at Northern Community Radio and even loggers in the woods note the changing Northern Minnesota biome. The growing season lasts longer. Winter freezes less deeply. Species more common to the south thrive here as never before.
Matt McGrath at the BBC reports that scientists have studied the expansion of cattails into more northern lakes. This hazard of climate change could dramatically increase the amount of naturally-produced methane in the atmosphere.
Incubated in the lab for 150 days the scientists found that cattails produced over 400 times the level of methane compared to conifers. The researchers believe that chemicals in both coniferous and deciduous trees restrict the ability of the microbes to produce the gas.
“The cattails don’t have the same chemicals and so they are no longer inhibiting the microbes from producing methane,” senior author Dr Andrew Tanentzap, from the University of Cambridge, told BBC News,
“By now comparing what’s happening in the reed beds to what’s might happening beneath a forest – wow, it’s a massive difference!”
The researchers believe they have discovered a new mechanism that has the potential to cause substantially more greenhouse gases to be produced by freshwater lakes. They say the warming climate that promotes the growth of aquatic plants has the potential to trigger a damaging feedback loop in natural ecosystems.
In other words, a warmer climate means more cattails, and more methane, and then an even warmer climate.
So, cattails grow in wetlands and conifers, other than black spruce, tamarack, and cedar don’t. Does this mean we should be draining wetlands and planting pine trees?
No, the problem isn’t cattails or wetlands, it’s that the retreat of the boreal forest produces more methane naturally, which causes more warming. Something we would need to prepare for — especially if we make our living in the woods.
This is interesting but I think people are going to be confused as to what is the cause and what is the effect.
The title of the underlying article is actually clearer in a wonkish way: “Climate-driven shifts in sediment chemistry enhance methane production in northern lakes.” (https://www.nature.com/articles/s41467-018-04236-2)
Looks like we broke the terrarium. Question is can it be fixed from the inside ? For the sake of everybody’s grandkids we better get on it.