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Land-use change occurs nowhere more rapidly than in the tropics, where the imbalance between deforestation and forest regrowth has large consequences for the global carbon cycle. However, considerable uncertainty remains about the rate of biomass recovery in secondary forests, and how these rates are influenced by climate, landscape, and prior land use. Here we analyse aboveground biomass recovery during secondary succession in 45 forest sites and about 1,500 forest plots covering the major environmental gradients in the Neotropics. The studied secondary forests are highly productive and resilient. Aboveground biomass recovery after 20 years was on average 122 megagrams per hectare (Mg ha(-1)), corresponding to a net carbon uptake of 3.05 Mg C ha(-1) yr(-1), 11 times the uptake rate of old-growth forests. Aboveground biomass stocks took a median time of 66 years to recover to 90% of old-growth values. Aboveground biomass recovery after 20 years varied 11.3-fold (from 20 to 225 Mg ha(-1)) across sites, and this recovery increased with water availability (higher local rainfall and lower climatic water deficit). We present a biomass recovery map of Latin America, which illustrates geographical and climatic variation in carbon sequestration potential during forest regrowth. The map will support policies to minimize forest loss in areas where biomass resilience is naturally low (such as seasonally dry forest regions) and promote forest regeneration and restoration in humid tropical lowland areas with high biomass resilience.

Critical analysis of the Latin American bibliographical production over the last 10 years regarding the adherence/non-adherence to treatment of people with chronic health problems: leprosy, tuberculosis, hypertension, diabetes and AIDS. Thirty six articles were analyzed identifying the variables: year of publication, publication area and kind of study. Most of the articles (27) were produced by professionals of the medical area, in epidemiological studies, and of the nursing area (7) in qualitative and quanti-qualitative studies. The scientific production on the subject increased until 2002, when it began to drop. The authors repeatedly defended the idea that the role of the patient is to follow the recommendations of the health professional and that the patient is free to follow or not the treatment, the professional however being exempt from the responsibility for the consequences of this decision. The greater part of factors pointed out by the authors as contributing to non-adherence relates to the patient, showing that the major responsibility for the adherence / non-adherence to treatment is conferred upon him. The measures the authors indicate for solving the problem point to responsibility of professionals, health services, governments and teaching institutions.