Conservation scientists generally agree that many types of protected areas will be needed to protect tropical forests. But little is known of the comparative performance of inhabited and uninhabited reserves in slowing the most extreme form of forest disturbance: conversion to agriculture. We used satellite-based maps of land cover and fire occurrence in the Brazilian Amazon to compare the performance of large (> 10,000 ha) uninhabited (parks) and inhabited (indigenous lands, extractive reserves, and national forests) reserves. Reserves significantly reduced both deforestation and fire. Deforestation was 1.7 (extractive reserves) to 20 (parks) times higher along the outside versus the inside of the reserve perimeters and fire occurrence was 4 (indigenous lands) to 9 (national forests) times higher. No strong difference in the inhibition of deforestation (p = 0. 11) or fire (p = 0.34) was found between parks and indigenous lands. However, uninhabited reserves tended to be located away from areas of high deforestation and burning rates. In contrast, indigenous lands were often created in response to frontier expansion, and many prevented deforestation completely despite high rates of deforestation along their boundaries. The inhibitory effect of indigenous lands on deforestation was strong after centuries of contact with the national society and was not correlated with indigenous population density. Indigenous lands occupy one-fifth of the Brazilian Amazon-five times the area under protection in parks--and are currently the most important barrier to Amazon deforestation. As the protected-area network expands from 36% to 41% of the Brazilian Amazon over the coming years, the greatest challenge will be successful reserve implementation in high-risk areas of frontier expansion as indigenous lands are strengthened. This success will depend on a broad base of political support.

Government commitments and market transitions lay the foundation for an effort to save the forest and reduce carbon emission.

The current annual rates of tropical deforestation from Brazil and Indonesia alone would equal four-fifths of the emissions reductions gained by implementing the Kyoto Protocol in its first commitment period, jeopardizing the goal of Protocol to avoid "dangerous anthropogenic interference" with the climate system. We propose the novel concept of "compensated reduction", whereby countries that elect to reduce national level deforestation to below a previously determined historical level would receive post facto compensation, and commit to stabilize or further reduce deforestation in the future. Such a program could create large-scale incentives to reduce tropical deforestation, as well as for broader developing country participation in the Kyoto Protocol, and leverage support for the continuity of the Protocol beyond the 2008-2012 first commitment period.

According to some conservationists, large, pristine, uninhabited parks are the defining criterion of success in conserving tropical forests. They argue that human residents in tropical forests inevitably deplete populations of large animals through hunting, which triggers a chain reaction of ecological events that greatly diminish the conservation value of these forests. Hence, they believe that removal of people from tropical forests is an essential step in the creation of successful parks and in the conservation of nature in the tropics. This approach can lead to undesirable consequences, however. Forest residents—and rural people generally—are potent political actors in tropical forest regions and an essential component of the environmental political constituencies that are necessary for the long‐term conservation of tropical forests. In Amazonia and elsewhere, rural people are defending far bigger areas of tropical forest from unfettered deforestation and logging than are parks, thereby conserving the ecological services provided by these forests and the majority of their component plant and animal species. Moreover, the data are too sparse to judge the effects of forest peoples on populations of large forest animals. The establishment of pristine, tropical forest parks is an important conservation goal, but the exclusive pursuit of this goal undermines the broader objectives of conservation when it identifies forest residents and other rural people as the enemies of nature.

Ongoing alliances between indigenous peoples and conservation organizations in the BrazilianAmazon have helped achieve the official recognition of ∼1 million km 2 of indigenous lands. The future of Amazonian indigenous reserves is of strategic importance for the fate of biodiversity in the region. We examined the legislation governing resource use on indigenous lands and summarize the history of the Kayapo people's consolidation of their >100,000 km 2 territory. Like many Amazonian indigenous peoples, the Kayapo have halted the expansion of the agricultural frontier on their lands but allow selective logging and gold mining. Prospects for long-term conservation and sustainability in these lands depend on indigenous peoples' understandings of their resource base and on available economic alternatives. Although forest conservation is not guaranteed by either tenure security or indigenous knowledge, (ISA) 15-year partnership with the peoples of the Xingu Indigenous Park, with projects centered on territorial monitoring and control, education, community organization, and economic alternatives. The recent agreement on ecological restoration of the Xingu River headwaters between ranchers and private companies, indigenous peoples, and environmentalists, brokered by ISA, marks the emergence of an indigenous and conservation alliance of sufficient cohesiveness and legitimacy to negotiate effectively at a regional scale. indigenous societies' relatively egalitarian common-property resource management regimes-along with adequate incentives and long-term partnerships with conservation organizations-can achieve this result. Successful initiatives include Conservation International's long-term project with the A'ukre Kayapo village and incipient large-scale territorial monitoring and control in the Kayapo territory, and the Instituto SocioAmbiental Alianzas de Conservación con Indígenas del AmazonasResumen: Las alianzas actuales entre indígenas y organizaciones de conservación en el Amazonas Brasileño han ayudado a obtener el reconocimiento oficial de ∼1 millón de km 2 enáreas indígenas. El futuro del as reservas indígenas amazónicas es de importancia estratégica para el futuro de la biodiversidad en la región. Examinamos la legislación que rige a la utilización de recursos en zonas indígenas y sintetizamos la historia de la consolidación del territorio > 100,000 km 2 de la etnia Kayapo. Como muchos grupos Amazónicos, los Kayapo han detenido la expansión de la frontera agrícola en sus tierras pero permiten actividades madereras y mineras selectivas. Las perspectivas de conservación y sustentabilidad a largo plazo en estas tierras dependen del entendimiento de su base de recursos y de las alternativas económicas disponibles por parte de los grupos indígenas. A pesar de que ni la seguridad en la posesión ni el conocimiento indígena garantizan la conservación de los bosques, los regímenes indígenas de gestión de recursos de propiedad común relativamente igualitarios en conjunto con incentivos adecuados y asociaciones con organiza...