Is small-scale agriculture really the main driver of deforestation in the Peruvian Amazon? Moving beyond the prevailing narrative

A key premise underlying discussion about deforestation in Amazonian Peru is that small-scale or so-called migratory agriculture is the main driver of deforestation. This premise has been expressed in government documents and public outreach events. How the Peruvian government understands drivers of deforestation in the Amazon has profound implications for how it will confront the problem. It is therefore important to critically revisit assumptions under-lying this narrative. We find that the narrative is based on remote sensing of deforestation patch sizes but not on field data, potentially conflating distinct drivers of deforestation under the umbrella of “migratory,” “small-scale,” or “subsistence” agriculture. In fact, small patches of deforested land may indicate any number of processes, including sustainable fallow management and agroforestry. Moreover, the data underlying the narrative tell us little about the actors driving these processes or their motivations. Different pro-cesses have distinct implications for environmental sustainability and require targeted policy responses. We unpack these diverse actors, geographies, and motivations of small-patch deforestation in the Peruvian Amazon and argue that differentiating among these drivers is necessary to develop appropriate policy responses. We call for researchers to revisit assumptions and critically assess the motivations of observed deforestation to appropriately target policy action

A Comparison of the Length of Two Distinct Rest Periods in Interval Training as Methods of Increasing Cardio-respiratory Efficiency

The purpose of this investigation was to determine the effects of holding the work load constant and changing the rest periods between work intervals, upon the improvement of cardio respiratory efficiency of track men. During the spring semester of the 1965-66 school year, 27 freshmen students enrolled in the basic instruction program at South Dakota State University, who had indicated by questionnaire they had lettered in track in high school, volunteered for the program. The subjects were randomly placed into two experimental groups and one control group. After the completion of the testing period and statistical procedure employed, the study indicated the methods of training used in this experiment improved cardio-respiratory efficiency of the experimental groups significantly in comparison to the control group. The study also indicated that the unknown rest period group seems to be superior to the three minute rest period group in the recovery of the heart after exercise. (see more in text

The Native Population of Amazonia in 1492 Reconsidered

Since 1965 I have made several attempts to estimate the native population of Amazonia in 1492. My method was to determine rough habitat densities, which project to totals for Greater Amazonia of from 5.1 to 6.8 million. I now reject this method, given that the denser populations were mostly clustered rather than evenly dispersed. I nevertheless still believe that a total of at least 5 to 6 million is reasonable.Desde 1965 he realizado distintas estimaciones sobre la población nativa de la Amazonía en 1492. Mi método fue determinar la densidad de población aproximada, que suponía un total entre 5,1 y 6,8 millones para la Gran Amazonía. Actualmente cuestiono este método, dado que las comunidades que tenían mayor densidad de población, estaban concentradas en núcleos más densos, y no tan dispersos como antes pensaba. De todos modos, creo que manejar una cantidad de población entre 5 y 6 millones sigue siendo razonable

An improved methodology for the recovery of Zea mays and other large crop pollen, with implications for environmental archaeology in the Neotropics

We present a simple sieving methodology to aid the recovery of large cultigen pollen grains, such as maize (Zea mays L.), manioc (Manihot esculenta Crantz), and sweet potato (Ipomoea batatas L.), among others, for the detection of food production using fossil pollen analysis of lake sediments in the tropical Americas. The new methodology was tested on three large study lakes located next to known and/or excavated pre-Columbian archaeological sites in South and Central America. Five paired samples, one treated by sieving, the other prepared using standard methodology, were compared for each of the three sites. Using the new methodology, chemically digested sediment samples were passed through a 53 µm sieve, and the residue was retained, mounted in silicone oil, and counted for large cultigen pollen grains. The filtrate was mounted and analysed for pollen according to standard palynological procedures. Zea mays (L.) was recovered from the sediments of all three study lakes using the sieving technique, where no cultigen pollen had been previously recorded using the standard methodology. Confidence intervals demonstrate there is no significant difference in pollen assemblages between the sieved versus unsieved samples. Equal numbers of exotic Lycopodium spores added to both the filtrate and residue of the sieved samples allow for direct comparison of cultigen pollen abundance with the standard terrestrial pollen count. Our technique enables the isolation and rapid scanning for maize and other cultigen pollen in lake sediments, which, in conjunction with charcoal and pollen records, is key to determining land-use patterns and the environmental impact of pre-Columbian societies

Pre-Columbian land use in the ring-ditch region of the Bolivian Amazon

The nature and extent of pre-Columbian (pre-1492 AD) human impact in Amazonia is a contentious issue. The Bolivian Amazon has yielded some of the most impressive evidence for large and complex pre-Columbian societies in the Amazon basin, yet there remains relatively little data concerning the land use of these societies over time. Palaeoecology, when integrated with archaeological data, has the potential to fill these gaps in our knowledge. We present a 6,000-year record of anthropogenic burning, agriculture and vegetation change, from an oxbow lake located adjacent to a pre-Columbian ring-ditch in north-east Bolivia (13°15’44” S, 63°42’37” W). Human occupation around the lake site is inferred from pollen and phytoliths of maize (Zea mays L.) and macroscopic charcoal evidence of anthropogenic burning. First occupation around the lake was radiocarbon dated to ~2500 years BP. The persistence of maize in the record from ~1850 BP suggests that it was an important crop grown in the ringditch region in pre-Columbian times, and abundant macroscopic charcoal suggests that pre-Columbian land management entailed more extensive burning of the landscape than the slash-and-burn agriculture practised around the site today. The site was occupied continuously until near-modern times, although there is evidence for a decline in agricultural intensity or change in land use strategy, and possible population decline, from ~600-500 BP. The long and continuous occupation, which predates the establishment of rainforest in the region, suggests that pre-Columbian land use may have had a significant influence on ecosystem development at this site over the last ~2000 years

Interdisciplinary progress in approaches to address social-ecological and ecocultural systems

SUMMARYThe emergent human cultures have shaped, and in turn been shaped by, local ecosystems. Yet humanity's intense modification of the environment has resulted in dramatic worldwide declines in natural and cultural capital. Social-ecological systems are becoming more vulnerable through the disruption of livelihoods, governance, institutions, resources and cultural traditions. This paper reviews the environmental sub-disciplines that have emerged to seek solutions for conservation and maintenance of the resilience of social-ecological systems. It shows that a central component is engagement with the knowledges of people within their contexts. Local knowledges of nature (traditional, indigenous, local ecological knowledge and ecoliteracy) are used by place-based cultures to guide actions towards nature. The importance of new engagements between different knowledges is now becoming more widely recognized by scientific institutions. Yet there still exist many false dualisms (for example local knowledge versus science) which tend to emphasize a superiority of one over the other. Ecocultures retain or strive to regain their connections with the environment, and thus improve their own resilience. Revitalization projects offer ways to connect knowledge with action to produce optimal outcomes for both nature and culture, suggesting that systems can be redesigned by emphasis on incorporation of local and traditional knowledge systems.</jats:p

Coastal risk mitigation by green infrastructure in Latin America

This paper aims to highlight the prevailing experiences of Latin America and to clarify what ‘green infrastructure’ entails in addition to describing seven case studies from a range of coastal ecosystems (wetlands, coastal dunes, beaches and coral reefs) at scales varying from local to regional. The case studies are categorised according to their degree of naturalness (nature-based, engineered ecosystems, soft engineering, ecologically enhanced hard infrastructure and de-engineering). Generally, the implementation of green infrastructure projects aims to increase resilience, enhance the provision of ecosystem services, recover biodiversity, reduce the negative effects of hard infrastructure and implement corrective measures. The greatest benefits of these projects relate to the creation of multi-functional spaces, which often combine the above advantages with improved opportunities for recreation and/or economic activities. It is hoped that this paper will disseminate the experience in green infrastructure among academics and practitioners and stimulate wider adoption of green infrastructure projects and good practices

Historical ecology, human niche construction and landscape in pre-Columbian Amazonia: a case study of the geoglyph builders of Acre, Brazil

This paper applies concepts from the fields of historical ecology and human niche construction theory to interpret archaeological and palaeoecological data from the Brazilian state of Acre, southwest Amazonia, where modern deforestation has revealed hundreds of pre-Columbian monumental earthworks called 'geoglyphs', largely built between ca. 2000–650 cal. BP (calibrated years before present). Our main objective was to move away from the debate which currently dominates Amazonian archaeology over large- vs. small-scale pre-Columbian environmental impacts, and instead offer a more nuanced interpretation of human-environment interactions in our specific study area. Despite the difficulties presented by working with an incomplete regional archaeological dataset, interpreting our findings in light of these theoretical frameworks allowed us to re-think landscape history and ask new questions about a possible relationship between anthropogenic forests, symbolic capital and monument building in our particular study area

MACHADOS DE PEDRA VERSUS MACHADOS DE METAL: A AMBIGUIDADE DA AGRICULTURA DE COIVARA NA AMAZÔNIA PRÉ-HISTÓRICA

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