Forest Ecosystems In A Changing World
LTREB Data
Reference Watersheds:
Whole Watershed Acidification Experiment:
Fertilizer History (1989-2019)
Litterfall mass (1988-2015)
Canopy architecture (2011)
Soil Chemistry (2011)
Lysimeter Data (1989-2012)
Root data (1991)
O Horizon root data (2012)
Fine root data (2013)
Soil Moisture (2007-2019)
Leaf decay/soil density fractions (2017-2020)
Long-Term Soil Productivity (LTSP) Experiment:
Tree inventory (2009)
Damage assessment (2011)
Lysimeter Data (1996-2020)
Long-term Monitoring:
Climatological, hydrological, and water chemistry data:
www.fs.usda.gov/rds/efrdata/efr/2
Rain chemistry data since 1978 (NADP site WV18):
Dry deposition data since 1989 (CASTNET site PAR107):
Smart Forest Real-Time Data for WS 4
Other data collected by forest service personnel are available by written request to Frederica Wood (fwood@fs.fed.us) and include vegetation, litter fall, soil, and soil solution measurements.
Major Findings (click on images to enlarge)
There are strong links between precipitation chemistry at the Fernow and human activities – both the bad (industrial pollution) & the good (policies that mitigate air pollution).
Nitrate and sulfate concentrations in rain at the Fernow strongly correlate (R2 = 0.79) with EPA estimates of NOx and SOx emissions for the entire US.
Nitrate concentrations in rain have decreased ~48% since 1997 at the Fernow and reflect a similar decline in US NOx emissions.
The composition of tree species at the Fernow has changed, and the extent of change is related to management practices.
Sugar maple increased despite declining populations at other locations in the northeastern US.
Management practices, or natural changes, which favor certain tree species might delay or accelerate the onset of nitrogen saturation.
Small watersheds with more sugar maple lose more nitrate in stream water. Those with more chestnut oak lose less nitrate in stream water.
Small plots with more sugar maple produce more nitrate. Those with more chestnut oak produce less.
The growth response of trees to N additions is short-lived and species specific.
The growth of trees at the Fernow was initially stimulated by additions of ammonium sulfate. However, this stimulation was short-lived (~7 years) and not observed in plots dominated by red maple & sweet birch.
Increased nitrogen availability is associated with reduced tree species diversity.
In untreated watersheds, more nitrate production is associated with fewer tree species. And experimental additions of ammonium sulfate have reduced the number of tree species from 11 to 9 species in a regenerating forest.
Long-term data from WS 4 contributes to an analysis of trends in stream nitrogen for forested catchments across the United States (see Argerich et al. 2013). (See video)