Historical landscape domestication in ancestral forests with nutrient-poor soils in northwestern Amazonia

Pre-Columbian soil fertilization and current management maintain food resource availability in old-growth Amazonian forests

“…Although all archaeological sites mapped in both regions contain ADE sites with ceramics, which indicate sedentary pre-Columbian occupation (Neves et al 2003), the ancient histories of the regions differ. Archaeological sites of the lower Tapajós River basin are mainly associated with the Tapajó or Santarém pottery, which is affiliated with the Incised and Punctate tradition (Stenborg 2016;Figueiredo 2019), while many sites in the middle-upper Madeira River basin are multi-componential, with the most recent layer containing the Fig. 1 a) The location of the protected areas studied in the Brazilian Amazon, b) the Tapajós National Forest in the lower Tapajós River basin, and c) the Humaitá National Forest and Jiahui Indigenous Land in the upper-middle Madeira River basin.…”

“…Altitude varies among forest plots in the Madeira River basin (80-110 m) and in the Tapajós River basin (150-200 m), and this variation was detected using SRTM (Shuttle Radar Topography Mission) images available at http://www.dsr.inpe.br/topodata/ Polychrome pottery tradition (Moraes and Neves 2012;Barreto et al 2016). Before this study, 148 archaeological sites had been recorded in the lower Tapajós River basin, in an area of 10,000 km 2 , including 13 sites inside the FLONA Tapajós (e.g., Schaan et al 2015;Stenborg, 2016;Stenborg et al 2018;Figueiredo 2019). Almost 70% of these archaeological sites are located on the interfluve (away from major Amazonian rivers), 6% are located on hillsides, and only 24% are located along the Tapajós River, secondary rivers and lakes (Stenborg et al 2018).…”

“…Due to lack of funding we could not date the charcoal found in our samples, but as suggested in the literature we assumed that charcoal above 20 cm is more likely to be associated with modern fires and below this layer is more likely to be associated with pre-Columbian fires (McMichael et al 2012). ADE sites in the Flona Tapajós were dated between 3362 and 3160 cal BP to 666-622 and 612-559 cal BP (Figueiredo 2019), and 530-450 cal BP (Maezumi et al 2018a). Also, ADE sites across Amazonia are likely older than 350 years BP according to the literature review of de Souza et al (2019).…”

“…Signs of landscape domestication can also be detected by assessing the distribution and abundance of useful, managed and/or domesticated species (Clement and Cassino 2018), as observed in Central Amazonia (Levis et al 2012;Ferreira et al 2019), Western Amazonia (Franco- Moraes et al 2019) and across the Amazon basin (Levis et al 2017). At least 85 arboreal species, mostly used for food, have populations domesticated to some degree by pre-Columbian peoples in Amazonia (Levis et al 2017), and they are concentrated in and around settlements due to numerous historical management practices (Levis et al 2018).…”

Edaphic Factors and Flooding Periodicity Determining Forest Types in a Topographic Gradient in the Northern Brazilian Amazonia

“…Its predominant covering is defined as dense and open ombrophilous forests [2][3], but throughout the Amazonian biome there are many different forest types that may be distinguished by their floristic composition and structure due to the large environmental heterogeneity [4][5]. In general, the factors modeling the different forest types are attributed mainly to the climatic variations, hydroedaphic conditions, topography, and anthropogenic interferences, all interacting and acting at different spatial scales [6][7][8][9]. This congregation of factors generates different structural and floristic shades with different ecosystem values, but generally information on the weight of each one, in the local and regional context, is little known due to the gigantism of the Amazonia, which makes sampling in peripheral areas a difficult process [3,10].…”