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Updated: May 24, 2026
06:27
Simulating Impacts of Ice Storms on Forest Ecosystems
Published on: June 30, 2020
Complex response of the forest nitrogen cycle to climate change
Susana Bernal1, Lars O Hedin, Gene E Likens
1Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08542, USA. sbernal@ceab.csic.es
Summary
Historic forest cutting, not climate change, significantly reduced watershed nitrate export over 46 years. Long-term data reveal past disturbances obscure modern climate impacts on forest nitrogen cycling.
Area of Science:
- Ecology
- Biogeochemistry
- Environmental Science
Background:
- Climate change impacts on ecosystem nutrient cycling are poorly understood.
- Long-term ecological records are crucial for distinguishing climate effects from other anthropogenic influences.
- The Hubbard Brook Experimental Forest provides a unique, extensive dataset for studying watershed dynamics.
Purpose of the Study:
- To investigate the drivers of a significant decline in watershed nitrate export over 46 years.
- To differentiate the impacts of climate change from historical land use on the forest nitrogen cycle.
- To assess the influence of past perturbations on interpreting modern ecological trends.
Main Methods:
- Analysis of the longest available global record of watershed nutrient and climate dynamics.
- Empirical analyses and model calculations to separate climate effects from historical perturbations.
- Quantification of the contribution of climate factors versus past forest cutting to nitrogen export changes.
Main Results:
- Climate change alone could not account for the >90% drop in nitrate export.
- Increased soil temperature and altered water flow explained at most 40% of the nitrate decline.
- Historical forest cutting explained 50-60% of the observed reduction in nitrogen export.
Conclusions:
- Long-lasting effects of historical land use can mask the influence of contemporary climate change on forest nitrogen cycling.
- Interpreting long-term ecological trends requires careful consideration of past disturbances.
- Ecosystem responses to climate change may be obscured by legacies of historical perturbations.
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