OOS 50-4
Harvard Forest LTER program: The role of historical studies in ecological research and conservation planning
The guiding question of the Harvard Forest LTER program: What will be the multiple and interactive effects of climate change, natural disturbances, biotic interactions, human land-use, and forest dynamics on landscape-scale ecosystem dynamics, processes, and services over the next 50 years? How do these insights inform and motivate conservation action in the face of future land-use and environmental change?
Paleoecological, archaeological, and historical research provide a unique long-term perspective that inform this and related questions concerning human-ecosystem-environment interactions, explicitly: (1) were past environmental and ecological transitions smooth or abrupt and what were their drivers; (2) how do abrupt transitions in one ecosystem relate (in timing and rate) to those in other ecosystems regionally; and (3) how do human actions and land-use regimes shape and/or respond to episodes of rapid changes in climate and vegetation? In turn, the resulting data sets inform our efforts to forecast future dynamics and scenarios and they play a major role in inspiring and guiding our work in conservation policy, land protection, and management.
Results/Conclusions
Integrated studies reveal strong evidence for cultural continuity in hunter-gatherer-collector subsistence patterns during pre-history and a negligible role for humans and limited role for fire in shaping vegetation patterns. Conversely, there is strong evidence that climate exerted a controlling influence structuring biotic assemblages and dynamics; human populations were responsive to these environmental and vegetation changes. Slow progressive changes in climate and plant assemblages were punctuated by abrupt transitions in forest ecosystems associated with rapid changes in temperature and precipitation interacting with extreme droughts.
Historical land-use (deforestation, agriculture and abandonment, reforestation) conditions most ecosystems today through biotic, structural, and chemical legacies and the inertia of lengthy processes such as soil and forest development, plant dispersal, and animal migration.
Emerging perspectives for conservation include: recognition that history has provided the region with a remarkable second chance to conserve its forests; motivation to advance forest and agricultural land protection to cope with looming land-use and climate impacts; advocacy for employing historically consistent approaches to land management, especially diversified agriculture rather than fire in maintaining culturally-derived biodiversity; hubris regarding the human capacity to manage environmental disturbances; and a healthy regard for the capacity of natural ecosystems to cope with stress and disturbance.