Charles R. Clement

1492 and the loss of amazonian crop genetic resources. I. The relation between domestication and human population decline

There may have been 4–5 million people in Amazonia at the time of European contact. These people cultivated or managed at least 138 plant species in 1492. Many of these crop genetic resources were human artifacts that required human intervention for their maintenance, i.e., they were in an advanced state of domestication. Consequently, there was a relationship between the decline of Amazonian Amerindian populations and the loss of their crop genetic heritage after contact. This relationship was influenced by the crop’s degree of domestication, its life history, the degree of landscape domestication where it was grown, the number of human societies that used it, and its importance to these societies. Amazonian crop genetic erosion probably reflects an order of magnitude loss and the losses continue today.RésuméA Amazônia poderia ter tido de 4 a 5 milhÕes de habitantes quando os Europeus chegaram. Estes povos cultivaram ou manejaram pelo menos 138 espécies vegetais em 1492. Muitos destes recursos genéticos eram artefatos humanos que requeriam a intervenção humana para sua manutenção, ou seja, estavam num estado avançado de domesticação. Conseqiientemente, existiu uma relaçao entre o declínio das populaçÕes indigenas da Amazônia e a perda de seus recursos genéticos apòs o contato. Esta relaç00E3o foi influenciada pelo grau de domesticação do cultivo, sua história de vida, o grau de domesticação da paisagem em que foi cultivada, o número de sociedades indigenas que o utilizou, e sua importância a estas sociedades. A erosão dos recursos genéticos indigenas da Amazônia provavelmente reflete uma perda de um ordern de magnitude e as perdas continuam hoje.

The domestication of Amazonia before European conquest.

During the twentieth century, Amazonia was widely regarded as relatively pristine nature, little impacted by human history. This view remains popular despite mounting evidence of substantial human influence over millennial scales across the region. Here, we review the evidence of an anthropogenic Amazonia in response to claims of sparse populations across broad portions of the region. Amazonia was a major centre of crop domestication, with at least 83 native species containing populations domesticated to some degree. Plant domestication occurs in domesticated landscapes, including highly modified Amazonian dark earths (ADEs) associated with large settled populations and that may cover greater than 0.1% of the region. Populations and food production expanded rapidly within land management systems in the mid-Holocene, and complex societies expanded in resource-rich areas creating domesticated landscapes with profound impacts on local and regional ecology. ADE food production projections support estimates of at least eight million people in 1492. By this time, highly diverse regional systems had developed across Amazonia where subsistence resources were created with plant and landscape domestication, including earthworks. This review argues that the Amazonian anthrome was no less socio-culturally diverse or populous than other tropical forested areas of the world prior to European conquest.

1492 and the loss of amazonian crop genetic resources. ii. crop Biogeography at contact

Fifty seven percent of the 138 cultivated plant species present in Amazonia at contact probably originated in the Amazon Basin and another 27% originated in lowland northern South America. The relationship between probable indigenous human population density and resultant agricultural intensification and crop diversity is used to propose the existence of a mosaic of crop genetic resource concentrations in Amazonia at contact, including two centers of diversity, four outlying minor centers, and five regions of diversity. This methodology is extrapolated to present a synthesis of South American crop genetic biogeography at contact.RésuméCinquenta e sete por cento das 138 espécies cultivadas na Amazônia no momento do contato provavelmente originaram na bacia amazônica e mais 27% originaram nas terras baixas do norte de América do Sul. A relação entre a densidade populacional indigena hipotética e a intensificação agrícola e a diversidade genética dos cultivos resultantes é usada para propor a existência de um mosaico de concentraçÕes de recursos genéticos na Amazônia no momento de contato, incluindo dois centros de diversidade, quatro centros per-iféricos menores, e cinco regiÕes de diversidade. A mesma metodologia é extrapolada para apresentar uma síntese da biogeografia da diversidade genética dos cultivos na America do Sul no momento de contato.

Pejibaye palm (Bactris gasipaes, Arecaceae): Multi-use potential for the lowland humid tropics

Pejibaye (Bactris gasipaes) was domesticated and widely used in the lowland humid neotropics during pre-Colombian times. Several research programs are underway to study and improve the species for use by farmers in ecologically suitable regions. Five breeding programs are outlined, each for a use to which the pejibaye may be put: (1) palmito (heart of palm), (2) whole fruit for human consumption, (3) flour and meal production, (4) oil production, and (5) animal ration from residues or purposefully bred varieties. Yield estimates and breeding problems are discussed. It is certain that the pejibaye can again become an important crop for the humid tropics.

Historical Human Footprint on Modern Tree Species Composition in the Purus-Madeira Interfluve, Central Amazonia

Background Native Amazonian populations managed forest resources in numerous ways, often creating oligarchic forests dominated by useful trees. The scale and spatial distribution of forest modification beyond pre-Columbian settlements is still unknown, although recent studies propose that human impact away from rivers was minimal. We tested the hypothesis that past human management of the useful tree community decreases with distance from rivers. Methodology/Principal Findings In six sites, we inventoried trees and palms with DBH≥10 cm and collected soil for charcoal analysis; we also mapped archaeological evidence around the sites. To quantify forest manipulation, we measured the relative abundance, richness and basal area of useful trees and palms. We found a strong negative exponential relationship between forest manipulation and distance to large rivers. Plots located from 10 to 20 km from a main river had 20–40% useful arboreal species, plots between 20 and 40 km had 12–23%, plots more than 40 km had less than 15%. Soil charcoal abundance was high in the two sites closest to secondary rivers, suggesting past agricultural practices. The shortest distance between archaeological evidence and plots was found in sites near rivers. Conclusions/Significance These results strongly suggest that past forest manipulation was not limited to the pre-Columbian settlements along major rivers, but extended over interfluvial areas considered to be primary forest today. The sustainable use of Amazonian forests will be most effective if it considers the degree of past landscape domestication, as human-modified landscapes concentrate useful plants for human sustainable use and management today.

Influence of Market Orientation on Food Plant Diversity of Farms Located on Amazonian Dark Earth in the Region of Manaus, Amazonas, Brazil

Homegardens may serve as reservoirs of agro-biodiversity on highly fertile, anthropogenic Amazonian Dark Earth (ADE) soils of the Amazon basin. However, as these soils are used more intensively for market-oriented agriculture, we suspected a decrease in their agro-biodiversity. We present data obtained from surveys on 16 farms where ADE was present in the region of Manaus, Amazonas, Brazil. When farms were separated into two groups by market orientation, species richness on the farms was not significantly influenced by market orientation, but there was less dominance (i.e., more diversity) for homegardens in the low-market orientation group (P < 0.1). The proportion of native species was not affected by market orientation. Hence, while the most market-oriented farms retained high species richness, homegardens located on them contained higher proportions of commercially interesting species.

Molecular marker-mediated validation of morphologically defined landraces of Pejibaye (Bactris gasipaes) and their phylogenetic relationships

RAPD markers were used to evaluate the genetic variability and structure of seven morphologically defined landraces of pejibaye (Bactris gasipaes Kunth, Palmae) to determine their validity and phylogenetic relationships. Two hundred and twenty plants of four Amazonian and three Central American landraces of var.gasipaes (the domesticate) and 30 plants of var.chichagui (H. Karsten) Henderson (the crop ancestor) maintained at the National Research Institute for Amazonia, Manaus, Amazonas, Brazil, were utilized. Eight RAPD primers yielded 113 markers, with good reproducibility, of which 97 were polymorphic. The four Amazonian landraces had an average heterozygosity of 0.30, with 86% polymorphism, greater than the Central American landraces (0.25; 74.3%) and var.chichagui (0.27; 80%). Among landrace genetic diversity (GST) was 15%, while within (Hs) was 85%, essentially equivalent to the AMOVA within (82.2%) and among (17.8%) variances. The Jaccard similarities, PCA, gene flow coefficients and Exact tests suggested that only one landrace exists in Central America, called Utilis after the first taxon described there, and that the Solimões landrace is part of the Putumayo landrace, rather than a separate entity. The Pará and Pampa Hermosa landraces were validated in accordance with their morphometric interpretations. The dendrogram of Nei’s genetic distances among valid landraces and var.chichagui supported the hypothesis of a single origin for pejibaye in southwestern Amazonia, with two migration routes: one to the northeast, becoming the Pará landrace, and another to the northwest along the Andes, spreading into western Amazonia (Pampa Hermosa and Putumayo landraces) and across the Andes, reaching Central America (Utilis landrace).

Dark Earths and manioc cultivation in Central Amazonia: a window on pre-Columbian agricultural systems?

Many commentators highlight the fertility of Anthropogenic Dark Earths (ADE), emphasizing their potential for sustainable agriculture. Some scholars believe that terra mulata (the less fertile, more extensive form of ADE) was created by means of agricultural practices used by large settled populations of pre-Columbian farmers. But what was it that these Amerindian farmers were growing? Until recently, scholarly consensus held that manioc does not perform well on ADE. New research on the middle Madeira River is showing, however, that this consensus was premature. In this region, the most common crop in ADE fields is bitter manioc. Farmers there have various landraces of manioc that they believe yield particularly well on ADE, and logically plant more of these varieties on ADE. Aspects of the behaviour and perception of manioc cultivation among 52 farmers at the community of Barro Alto were measured quantitatively on four terra firme soil types (Terra Preta, Terra Mulata, Oxisols and Ultisols). These farmers plant different configurations of landraces in different soils, according to their perception of the suitability of particular landraces and their characteristics to certain soil types and successional processes. This, in turn, shapes selective pressures on these varieties, as new genetic material incorporated from volunteer seedlings is more likely to contain traits present in the most prevalent landrace(s) in each soil type. Owing to localized population pressure at Barro Alto, manioc is under more intensive cultivation systems, with shorter cropping periods (5-10 months) and shorter fallow periods (1-2 years). The outcome of these processes is different co-evolutionary dynamics on ADE as opposed to non-anthropogenic soils. Further anthropological study of manioc swiddening in one of the richest agricultural environments in Amazonia can fill a gap in the literature, thus opening an additional window on the pre-Columbian period.

Chemical composition of the fruit mesocarp of three peach palm (Bactris gasipaes) populations grown in central Amazonia, Brazil.

The percent composition, soluble and insoluble food fibers, oil fatty acids and minerals were determined in the mesocarp of fruits of three peach palm (Bactris gasipaes Kunth) populations grown in Central Amazonia, Brazil. Amino acids were also determined in one of the populations. The mean protein levels ranged from 1.8 to 2.7%, lipid levels ranged from 3.5 to 11.1%, the nitrogen free fraction ranged from 24.3 to 35%, food fiber ranged from 5.2% to 8.7%, and energy ranged from 179.1 to 207.4 kcal%. All essential, as well as non-essential, amino acids were present, with tryptophan and methionine presenting the lowest mean concentrations. The mono-unsaturated oleic acid predominated in the oil, ranging from 42.8 to 60.8%, and palmitic acid was the most abundant saturated fatty acid, ranging from 24.1 to 42.3%. Among the essential fatty acids, linoleic acid was the most abundant, with a maximum of 5.4% in Pampa-8. The most important mineral elements were potassium, selenium and chromium, respectively corresponding to 12%, 9% and 9% of daily recommended allowances. Considering the nutritional potential of the fruit, we suggest its more frequent incorporation into the diet of the Amazonian population.

Secondary Forests on Anthropogenic Soils of the Middle Madeira River: Valuation, Local Knowledge, and Landscape Domestication in Brazilian Amazonia

Secondary Forests on Anthropogenic Soils of the Middle Madeira River: Valuation, Local Knowledge, and Landscape Domestication in Brazilian Amazonia. Anthropogenic forests and soils are widespread throughout Amazonia and are the product of the landscape domestication process carried out by Amazonian societies since pre-Colombian times. Areas of Terra Preta de Índio (TPI, Amazonian Dark Earths) are recognized by local rural residents and associated with specific forms of use and management of these soils and associated secondary forests. We used a quantitative approach to investigate how secondary forests on TPI are recognized and used by local residents along the middle Madeira River, Central Amazonia. Sixty-two residents were interviewed in three riverside communities and listed the ethnospecies and their uses in secondary forests on TPI and on non-anthropogenic soils (NAS). Local residents mentioned more ethnospecies on TPI (mean ± standard deviation: 19.5 ± 8.9) than on NAS (17.4 ± 8.5), and the use value of the environment to the informants (UVia) was higher on TPI (19 ± 5.7) than on NAS (16.2 ± 6.0). Eleven ethnospecies were classified as anthropogenic soil indicators, among which three intensively used palms are widely recognized as indicators of anthropogenic areas and two are domesticated to some degree. The intimate and lasting interactions between humans and TPI have favored the maintenance of secondary forests in these domesticated landscapes with a diverse assemblage of useful and domesticated species. Rural residents in Amazonia recognize these forests as an important source of food and other resources. The use, management, and traditional knowledge related to these domesticated landscapes may provide useful information for the understanding of Amazonian historical ecology and for the design of more efficient biodiversity management and conservation plans.ResumoFlorestas secundárias sobre solos antrópicos do médio Rio Madeira: valoração, conhecimento local e domesticação da paisagem na Amazônia Brasileira. Florestas e solos antrópicos são amplamente distribuídos na Amazônia e são resultado do processo de domesticação da paisagem pelas sociedades Amazônicas desde tempos pré-Colombianos. Áreas de Terra Preta de Índio (TPI) são reconhecidas por moradores locais e associadas com formas específicas de uso e manejo desses solos e das florestas secundárias associadas a eles. Utilizamos uma abordagem quantitativa para investigar como as florestas secundárias sobre TPI são conhecidas e utilizadas por moradores locais no médio Rio Madeira, Amazônia Central. Sessenta e dois moradores foram entrevistados em três comunidades ribeirinhas e listaram etnoespécies e os seus usos em florestas secundárias em TPI e em solos não-antrópicos (NAS). Os residentes locais mencionaram mais etnoespécies em TPI (média ± desvio padrão: 19,5 ± 8,9) do que em NAS (17,4 ± 8,5), e o valor de uso do ambiente para os informantes (UVia) foi maior em TPI (19 ± 5,7) do que em NAS(16,2 ± 6,0). Onze etnoespécies foram classificadas como indicadoras de solos antrópicos, entre as quais três palmeiras intensivamente utilizadas e amplamente reconhecidas como indicadoras de áreas antropogênicas, duas das quais domesticadas em algum grau. As interações íntimas e duradouras entre humanos e TPI nessas paisagens domesticadas favoreceram a manutenção de florestas secundárias com uma diversa assembléia de espécies úteis e domesticadas. Moradores locais na Amazônia reconhecem essas florestas como uma fonte importante de alimentos e de outros recursos. A utilização, manejo e o conhecimento tradicional relacionados a essas paisagens domesticadas podem fornecer informações úteis para o entendimento da ecologia histórica da Amazônia e para o desenvolvimento de estratégias mais eficientes de manejo e conservação da biodiversidade.