Four New Colloquia Posts
After a long hiatus (been working on a paper) we are pleased to announce the posting of four new works in our Colloquia:
Nataraja: India’s Cycle of Fire by Stephen J. Pyne may be found [here]. Dr. Pyne’s essay on the history of fire on the Indian subcontinent is a chapter from World Fire: The Culture of Fire on Earth (Pyne S.J., 1997, Univ of WA Press). He graciously sent it to W.I.S.E. as a companion piece to Roger Underwood’s Baden-Powell and Australian Bushfire Policy [Part 1 here, Part 2 here]. An extracted gem of a quote:
India’s biota, like Shiva, dances to their peculiar rhythm while fire turns the timeless wheel of the world. Perhaps nowhere else have the natural and the cultural parameters of fire converged so closely and so clearly. Human society and Indian biota resemble one other with uncanny fidelity. They share common origins, display a similar syncretism, organize themselves along related principles. Such has been their interaction over millennia that the geography of one reveals the geography of the other. The mosaic of peoples is interdependent with the mosaic of landscapes, not only as a reflection of those lands but as an active shaper of them (emphasis added). Indian geography is thus an expression of Indian history, but that history has a distinctive character, of which the nataraja is synecdoche, a timeless cycle that begins and ends with fire.
Stand Reconstruction and 200 Years of Forest Development on Selected Sites in the Upper South Umpqua Watershed, W.I.S.E. White Paper 2010-5 by yours truly (and the cause of the recent hiatus), examines the forest development pathways over the last 200 years in an Oregon Cascades watershed:
Several lines of evidence suggest that the prairies, savannas, and open forests have been persistent vegetation types in the Upper South Umpqua Watershed for the last few thousand years, at least. Precontact forest development pathways were mediated by frequent, purposeful, anthropogenic fires deliberately set by skilled practitioners, informed by long cultural experience and traditional ecological knowledge in order to achieve specific land management objectives. At a landscape scale the result was maintenance of an (ancient) anthropogenic mosaic of agro-ecological patches. In the absence, over the last 150 years, of purposeful anthropogenic fires, the anthropogenic mosaic has been invaded and obscured by (principally) Douglas-fir. As a result, the Upper South Umpqua Watershed is now at risk from a-historical, catastrophic stand-replacing fires.
In Pre-Columbian agricultural landscapes, ecosystem engineers, and self-organized patchiness in Amazonia by Doyle McKey, Stephen Rostain, Jose Iriarte, Bruno Glaser, Jago Jonathan Birk, Irene Holst, and Delphine Renard, the authors examine the manner in which arthropods and other critters have maintained nutrient-rich soils long after the pre-Columbian human residents created said soils:
Combining archeology, archeobotany, paleoecology, soil science, ecology, and aerial imagery, we show that pre-Columbian farmers of the Guianas coast constructed large raised-field complexes, growing on them crops including maize, manioc, and squash. Farmers created physical and biogeochemical heterogeneity in flat, marshy environments by constructing raised fields. When these fields were later abandoned, the mosaic of well-drained islands in the flooded matrix set in motion self-organizing processes driven by ecosystem engineers (ants, termites, earthworms, and woody plants) that occur preferentially on abandoned raised fields.
In The Columbian Encounter and the Little Ice Age: Abrupt Land Use Change, Fire, and Greenhouse Forcing by Robert A. Dull, Richard J. Nevle, William I. Woods, Dennis K. Bird, Shiri Avnery, and William M. Denevan, the (accomplished and distinguished) authors posit that Old World disease epidemics in the 1500’s eliminated anthropogenic fire along with the human population of Amazonia. The decline in human-driven carbon cycling was at a continental scale, and the reduction in emitted CO2 may have induced the Little Ice Age:
Pre-Columbian farmers of the Neotropical lowlands numbered an estimated 25 million by 1492, with at least 80 percent living within forest biomes. It is now well established that significant areas of Neotropical forests were cleared and burned to facilitate agricultural activities before the arrival of Europeans. Paleoecological and archaeological evidence shows that demographic pressure on forest resources—facilitated by anthropogenic burning—increased steadily throughout the Late Holocene, peaking when Europeans arrived in the late fifteenth century. The introduction of Old World diseases led to recurrent epidemics and resulted in an unprecedented population crash throughout the Neotropics. The rapid demographic collapse was mostly complete by 1650, by which time it is estimated that about 95 percent of all indigenous inhabitants of the region had perished. We review fire history records from throughout the Neotropical lowlands and report new high-resolution charcoal records and demographic estimates that together support the idea that the Neotropical lowlands went from being a net source of CO2 to the atmosphere before Columbus to a net carbon sink for several centuries following the Columbian encounter. We argue that the regrowth of Neotropical forests following the Columbian encounter led to terrestrial biospheric carbon sequestration on the order of 2 to 5 Pg C, thereby contributing to the well-documented decrease in atmospheric CO2 recorded in Antarctic ice cores from about 1500 through 1750, a trend previously attributed exclusively to decreases in solar irradiance and an increase in global volcanic activity. We conclude that the post-Columbian carbon sequestration event was a significant forcing mechanism.
It’s a hypothesis that is very difficult to test, but one that recognizes the historical impact of human beings on the environment. That theme permeates all four new Colloquia postings.
Our protocol with Colloquia postings is that comments there must be scholarly, commensurate with the scientific efforts of the authors. Less than scholarly comments on any of the postings are welcome, but should be placed here (see the leave a comment aplet below).
We endeavor to post the best, cutting-edge research papers, and all of these meet our stringent criteria. They are not too technical for the lay audience, though. I hope you enjoy them.
