To Bolivia again

Hi everybody,

I have the flight to Bolivia in few hours and I will spend there the next month. No scientific post for the next weeks, but I will try to post a lot of photos, you will feel like you are there too :-)

Stay tuned!

Roadmap for amazonists to INQUA 2011

Next week (21-27 July 2011) The XVIII INQUA-Congress will take place in Bern, Switzerland.
As expected, very few contributions will deal with the Amazon Basin during the Holocene. I went through the program and I spotted the following presentations and posters that could be of interest to those who follow this blog. If I have missed something let me know and I will update the list. By the way, the first oral presentation on this list is mine :-) If you come to INQUA it would be great to meet up and have a good Swiss beer together!! Hope to see you there!!

ORAL PRESENTATIONS:

• Human occupation and environmental change in south-western Amazonia during the Holocene.

• Palaeobotanical evidences of pre-Columbian agriculture in black soils (Terra Preta do indio) in western Amazonia

• Ecological response on environmental change in tropical South America during the late Quaternary

POSTERS:

• Human occupation and paleoenvironment during the Holocene of southern Brazil: Sangão and Garivaldino sites

• Source-bordering dunes in the eastern Bolivian lowlands – geomorphic variety and paleoenvironmental significance

• Tropical Wetland Formation in Belize: Ancient Maya and Natural Interactions in the Late Holocene

• Vegetation, climate, and fire history of the Páramo of Jimbura, southern Ecuador

• Pre-Columbian human land-use and impact in the Bolivian Amazon

• Early to Late Holocene climate, vegetation and fire history in the upland savannas of Guayana, SE Venezuela: fire regimes and community structure in a savanna-dominated area

• Landscape transformation and crop cultivation in two contrasting environments in Colombia: evidences of ancient agricultural raised fields

• Palaeohydrological variability of the Bolivian Amazon throughout the Holocene

• Paleoecological study of a Gran Sabana lake (SE Venezuela) during the last millennia: implications for Mauritia colonization and human settlement

• Late Holocene environmental changes based on diatom and pollen records from lake sediments of Laguna Encantada, in the Neotropical Gran Sabana (Venezuelan Guayana)

• Rapid paleohydrogical Holocene changes in the Amazon river and its implications on the carbon accumulation in floodplain lakes

• Paleoenvironmental trends in Venezuela during the last glacial cycle

Less than 1% of Amazonia is made of Terra Preta. Is that enough?

I’ve just read a review written by William Balée (2010) about the book ‘Amazonian Dark Earths: Origins, Properties, Management’. Balée considers that the discovery of Terra Preta is proof that people in pre-Columbian Amazonia, rather than adapting to environmental conditions, ‘created’ the environment they inhabited. This allowed the development of complex societies in the region regardless of environmental constraints (such as poor soils, floods, lack of protein...). People overcame all these problems by creating Terra Preta. This is an extract from Balée’s introduction: “This contribution refutes, in essence, the adaptationist view of Amazonian indigenous societies […]. It is intriguing that this refutation takes place in light of what constitutes less than 1% of the forested part of the region’s surface soils (Woods and Denevan 3.1:1). That small fraction, nevertheless, like the difference in DNA between humans and chimpanzees, takes on profound significance in terms of understanding […] agriculture, population, and settlement in the prehistory of the region.”

Can we really consider this 1% like the difference in the DNA between humans and chimpanzees?

An answer to this question is given by Bush and Silman (2007): “The hypothesis of widespread Amazonian landscape management is based on analyses of archaeological sites and the assumption that there was a large pre-contact Amazonian population (> 10 million people). A caveat must be applied to these data, and indeed all of the data that we have to date about human disturbance in the Amazon, which is that they are derived from just a few locations, and do not represent either a systematic or a randomized sampling design. There is no ecological component predicting which forest was most likely to be occupied. Was disturbance spread evenly across all of Amazonia or concentrated near human habitation? Is it safe to extrapolate results from sites where we know human habitation occurred to the rest of Amazonia? Ecologists are familiar with problems of scale. […] extrapolating observations from dot maps can be dangerous, especially when the dots represent discrete activities of limited spatial extent (eg terra preta formation).”

It is striking how scholars can have such differing views at such a basic methodological level! (-:

Another interesting point is where that 1% is found: terra preta sites (the “dots” Bush and Silman are talking about) are found along the courses of the major Amazon rivers (fig. 1).

Figure 1 Terra preta sites. From Glaser (2007)

The preference for settling along rivers would seem to indicate that environmental conditions (in this case closeness to fish protein and waterways) did in fact condition the development of pre-Columbian societies. If we consider terra preta as evidence of the existence of large permanent settlements established by complex societies, then its spatial distribution along major rivers would suggest precisely that social complexity developed where environmental conditions were good. And, as so many archaeologists and anthropologists have stressed before me, there is no basis to infer that large permanent settlements were also established in other areas further away from rivers, where environmental conditions would have been tougher. 

P.S.

I have just discovered a new post in the Blog of Neves about the same issue. have a look (in Portuguese): http://arqueologiadaflorestatropical.blogspot.com/

William Balée (2010). Amazonian Dark Earths Tipití: Journal of the Society for the Anthropology of Lowland South America


Bush, M., & Silman, M. (2007). Amazonian exploitation revisited: ecological asymmetry and the policy pendulum Frontiers in Ecology and the Environment, 5 (9), 457-465 DOI: 10.1890/070018


Glaser, B. (2007). Prehistorically modified soils of central Amazonia: a model for sustainable agriculture in the twenty-first century Philosophical Transactions of the Royal Society B: Biological Sciences, 362 (1478), 187-196 DOI: 10.1098/rstb.2006.1978