Demographic Threats to the Sustainability of Brazil Nut Exploitation

• DOI: 10.1126/science.1091698
• Publication Date: 2003-12-18T22:57:53Z
• Authors: Carlos A. Peres; Claudia Baider; Pieter A. Zuidema; Lúcia H. O. Wadt; Karen A. Kainer; Daisy A. P. Gomes...; Rafael P. Salomão; Luciana L. Simões; Eduardo R. N. Fra...; Fernando Cornejo ...; Rogério Gribel; Glenn H. Shepard; Milton Kanashiro; Peter Coventry; Douglas W. Yu; Andrew R. Watkinson; Robert P. Freckleton
• Keywords: 0301 basic medicine; Time Factors; Trees; Soil; Biologie/Milieukunde (BIOL); Models; Peru; Nuts; Conservation Of Natural Resources; Plant biology (Botany); Principal Component Analysis; Forestry; Biodiversity; Sustainable Development; Statistical; Life sciences; Crop Production; Sustainability; Priority Journal; Regression Analysis; Brazil Nut; Tree; Brazil; Crops, Agricultural; Bolivia; Conservation of Natural Resources; 330; Crops; Exploitation; Senescence; 03 medical and health sciences; Amazonia; Harvesting; Computer Simulation; Forest; Bertholletia Excelsa; Ecosystem; Demography; Nut; Population Density; Agricultural; Models, Statistical; Brasil; South America; 15. Life on land; Nonhuman; Economic Aspect; Bertholletia; Population Statistics; Environmental Sustainability; Nutrient

A comparative analysis of 23 populations of the Brazil nut tree ( Bertholletia excelsa ) across the Brazilian, Peruvian, and Bolivian Amazon shows that the history and intensity of Brazil nut exploitation are major determinants of population size structure. Populations subjected to persistent levels of harvest lack juvenile trees less than 60 centimeters in diameter at breast height; only populations with a history of either light or recent exploitation contain large numbers of juvenile trees. A harvesting model confirms that intensive exploitation levels over the past century are such that juvenile recruitment is insufficient to maintain populations over the long term. Without management, intensively harvested populations will succumb to a process of senescence and demographic collapse, threatening this cornerstone of the Amazonian extractive economy.