Just in time to tug at your patriotic heartstrings, newly published research shows that the American icons Walden Pond and Yellowstone National Park are losing treasured plant and animal life to climate change and fungus.

Two studies in this week’s Proceedings of the National Academy of Sciences document the disappearance of species in and around Massachusetts’ Walden Pond – made famous by naturalist Henry David Thoreau 156 years ago – and in Yellowstone in Wyoming.

Flowers vulnerable to rising temperatures, including buttercups, dogwoods, lilies, orchids, roses and violets, are dying out on Walden Pond, according to one of the studies, which is part of an ongoing effort to monitor the species first recorded by Thoreau. Some 25 percent, or 120 of the 473 species Thoreau documented, have vanished, and 34 percent, or 156, may face imminent extinction, says study author Charles Davis, a Ph.D. candidate in organismic and evolutionary biology at Harvard. Temperatures near Walden have risen 4.3 degrees Fahrenheit (2.4 degrees Celsius) over the past century and are expected to go up between 2 degrees and 11.5 degrees Fahrenheit (1.1 degrees and 6.4 degrees Celsius) over the next 100 years, according to the study.

"Species that can't cue in to erratic seasonality are having a harder time — it's an inability to synch your flowering time with temperature changes," Davis tells us.

In just 16 years, the number of permanently dry ponds in Yellowstone has quadrupled, the second study says: 19 of 49 that were full in 1992 and 1993 were dry last year, Discovery News notes. During that same time, more than half of the amphibian populations that rely on the ponds disappeared. Two frog species -- the boreal chorus frog (Pseudacris triseriata maculata) and the Columbia spotted frog (Rana luteiventris) – the boreal toad (Bufo boreas boreas), and the blotched tiger salamander (Ambystoma tigrinum melanostictum) were affected, BBC News reports.

Previous research showed that amphibians are disappearing faster than any other organisms. Changes in their habitat pose the biggest threat; the parasitic fungus amphibian chytrid has also been blamed. 

"This is really catastrophic to the local amphibian population, because obviously they need these environments to breed and exist as larvae," Sarah McMenamin, a Stanford University biology doctoral candidate and author of the second study, told Discovery News. Add fungus to that mix, she said, and "It's a triple whammy on the amphibians."

(Image of lone water lilly on Walden Pond via Flickr/Sage, https://www.flickr.com/photos/vickispix/)