@article {2612,
	title = {Climate variability and cultural eutrophication at Walden Pond (Massachusetts, USA) during the last 1800 years},
	journal = {PLOS ONE},
	volume = {131786944304936355638925103443261363251824210727417625108525645371825392233490545519069849653235772249},
	year = {2018},
	month = {Apr-04-2018},
	pages = {e0191755},
	abstract = {Recent shifts in the ecological condition of Walden Pond, MA, are of
potentially wide interest due to the lake{\textquoteright}s importance as a cultural,
historical, and recreational resource in addition to its scientific
value as an indicator of local and global environmental change. Algal
microfossils in six sediment cores document changes in hydroclimate and
trophic status of the lake during the last 1800 years and extend two
previous sediment core records of shorter length. Low percentages of
planktonic diatoms in the longest cores (WAL-3, WAL-15) indicate
shallowing and/or greater water clarity associated with a relatively
arid interval during the Medieval Climate Anomaly, ca. A.D. 1150-1300,
Cultural eutrophication of the lake since the A.D. 1920s caused diatoms
in the genera Asterionella and Synedra to increase in relative abundance
at the expense of Cyclotella, Discostella, and the chrysophyte alga
Mallomonas allorgel. Percentages of Asterionella and Synedra have
remained fairly stable since A.D. 2000 when a previous sediment core
study was conducted, but scaled chrysophytes have become more numerous.
These findings suggest that, although mitigation efforts have curtailed
anthropogenic nutrient inputs to Walden Pond, the lake has not returned
to the pre-impact condition described by Henry David Thoreau and may
become increasingly vulnerable to further changes in water quality in a
warmer and possibly wetter future.},
	keywords = {BOREAL LAKES, canada, CRAWFORD LAKE, DEPTH MODELS, ENVIRONMENTAL-CHANGE, ice-age, new-england, NORTH-AMERICA, NORTHEASTERN UNITED-STATES, organic-matter},
	doi = {10.1371/journal.pone.0191755},
	url = {https://www.sciencedaily.com/releases/2018/04/180404143418.htm},
	author = {Stager, J. Curt and Wiltse, Brendan and Hubeny, J. Bradford and Yankowsky, Eric and Nardelli, David and Primack, Richard},
	editor = {Doi, Hideyuki}
}
