Historical Ecology - Applied Historical Ecology

Applied Historical Ecology

Historical ecology involves an understanding of multiple fields of study such as archaeology and cultural history as well as ecological processes, species diversity, natural variability, and the impact of human-mediated disturbances. Having a broad understanding of landscapes allows historical ecology to be applied to various disciplines. Studying past relationships between humans and landscapes can successfully aid land managers by helping develop holistic, environmentally rational, and historically accurate plans of action. As summarized in the postulates of historical ecology, humans play significant roles in the creation and destruction of landscapes as well as in ecosystem function. Through experience, many indigenous societies learned how to effectively alter their landscapes and biotic distributions. Modern societies, seeking to curtail the magnitude of their effects on the landscape, can use historical ecology to promote sustainability by learning from the past. Farmers in the Amazonian region, for example, now utilize nutrient-rich terra preta to increase crop yields much like the indigenous societies that lived long before them.

Historical ecology can also aid in the goals of other fields of study. Conservation Biology recognizes different types of land management processes, each attempting to maintain the landscape and biota in their present form. Restoration ecology restores sites to their original function, structure, and components of biological diversity through active modification of the landscapes. Reclamation deals with shifting a degraded ecosystem back toward a higher value or use, but not necessarily to its original state. Replacement of an ecosystem would create an entirely new one. Revegetation involves new additions of biota into a landscape, not limited to the original inhabitants of an area. Each method can be enriched by the application of historical ecology and the past knowledge it supplies. The interdisciplinary nature of historical ecology would permit conservation biologists to create more effective and efficient landscape improvements. Reclamation and revegetation can use a historical perspective to determine what biota will be able to sustain large populations without threatening native biota of the landscape.

A tropical forest in particular needs to be studied extensively because it is a highly diverse, heterogeneous setting. Historical ecology can use archaeological sites within this setting to study past successes and failures of indigenous peoples. The use of swidden fires in Laos is an example of historical ecology as used by current land managers in policy-making. Swidden fires were originally considered a source of habitat degradation. This conclusion led the Laos government to discourage farmers from using swidden fires as a farming technique. However, recent research has found that swidden fires were practiced historically in Laos and were not, in fact, the source of degradation. Similar research revealed that habitat degradation originated from a population increase after the Vietnam War. The greater volume of people compelled the government to put pressure on farmers for increased agricultural production. Land managers no longer automatically eliminate the use of swidden fires, but rather the number of swidden fires that are set for government-sponsored agricultural purposes.

The San Francisco Estuary Institute also uses historical ecology to study human impacts on the California landscape to guide environmental management. A study of the wetlands of Elkhorn Slough near Monterey, California, sought to enhance conservation and restoration activities. By using historical data such as maps, charts, and aerial photographs, researchers were able to trace habitat change to built structures that had negatively altered the tidal flow into the estuaries dating from the early 1900s. The study further suggested using techniques that "imitate the complex structure of natural tidal wetlands and maintain connectivity with intact wetland habitats as well as with adjoining subtidal and upland habitats."