RESUMO
The Amazon rainforests have been undergoing unprecedented levels of human-induced disturbances. In addition to local impacts, such changes are likely to cascade following the eastern-western atmospheric flow generated by trade winds. We propose a model of spatial and temporal interactions created by this flow to estimate the spread of effects from local disturbances to downwind locations along atmospheric trajectories. The spatial component captures cascading effects propagated by neighboring regions, while the temporal component captures the persistence of local disturbances. Importantly, all these network effects can be described by a single matrix, acting as a spatial multiplier that amplifies local forest disturbances. This matrix holds practical implications for policymakers as they can use it to easily map where the damage of an initial forest disturbance is amplified and propagated to. We identify regions that are likely to cause the largest impact throughout the basin and those that are the most vulnerable to shocks caused by remote deforestation. On average, the presence of cascading effects mediated by winds in the Amazon doubles the impact of an initial damage. However, there is heterogeneity in this impact. While damage in some regions does not propagate, in others, amplification can reach 250%. Since we only account for spillovers mediated by winds, our multiplier of 2 should be seen as a lower bound.
Assuntos
Conservação dos Recursos Naturais , Florestas , Humanos , Floresta Úmida , VentoRESUMO
Innovation and improved practices in the livestock sector represent key opportunities tomeet global climate goals. This paper provides evidence that extension services can pro-mote pasture restoration in cattle ranching in Brazil. We use a randomized controlledtrial implemented in the context of the ABC Cerrado (a large-scale program launched in2014 aimed at fostering technology adoption through a combination of training andtechnical assistance) to examine the effects of different types of extension on agriculturalpractices, input use, and productivity. Providing technical assistance to previously trainedproducers promoted pasture restoration, induced farmers to use inputs more intensively,helped them to improve their management and soil conservation practices, and substan-tially increased revenues. A costbenefit calculation indicates that US$1 invested in theABC Cerrado program increased profits by US$1.08 to $1.45. Incorporating carbonsavings amplifies this return considerably.
Assuntos
Carbono , Gases de Efeito Estufa , Agricultura , Animais , Brasil , Carbono/análise , Sequestro de Carbono , Bovinos , Gases de Efeito Estufa/análiseRESUMO
Mílio colóide é doença degenerativa relativamente rara, de etiologia desconhecida. São descritos três tipos de degeneração colóide da pele: mílio colóide tipo adulto, mílio colóide juvenil e degeneração nodular colóide, Na variante do adulto a luz solar é fator importante, havendo casos desencadeados por bronzeamento artificial, na histologia observa-se lesão dérmica contendo material eosinofilico. Os autores relatam dois casos de mílio colóide tipo adulto e dazem uma revisão breve sobre a possível etiologia, a clínica e os achados histopatológicos, bem como sobre as modalidades terapêuticas para a doença