32 research outputs found

    Modelagem de crescimento e produção usando o modelo Simflora.

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    Importância da modelagem de dinâmica florestal na Amazônia Brasileira; Modelagem de crescimento e produção usando o Simflora; Outros documentos disponíveis; Instalação; Simulações únicas; Dados; Começando; Janelas de exibição; Rodando o modelo; Resultados; Simulando silvicultura; A escolha de módulos e valores dos parâmetros; Exemplo; Simulações múltiplas; Começando uma simulação múltipla; Criando um arquivo de dados de saída; Rodando simulações múltiplas; Examinando e analisando os resultados; Experiências de uso do Simflora e suas implicações para políticas públicas; Indonésia; Guiana Inglesa; Brasil; Padrões observados em relação à exploração madeireira e às lacunas de conhecimento de dinâmica florestal de diferentes países tropicais

    Modeling the Effects of Climate Variability and Climate Change on a Pastoral Farming System

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    A simulation model was used to investigate the pasture and animal production and gross margins of a typical all sheep permanent pasture farm in South Canterbury, New Zealand, using 60 years of current climate data, and also a climate change scenario. The model was run on a fixed management system at different stocking rates with and without destocking during feed shortages. Mean annual pasture production was 8060 kg/ha, with a coefficient of variation of 22%. Destocking enabled more stock to be carried on average, with higher, but rh.ore variable, returns. A climate change scenario of a 75% increase in CO2\u27 1.8°C rise in mean temperature, a 5% decrease in rainfall and an 8% increase in solar radiation produced 46% higher but more variable pasture yields, resulting in optimum stocking rates, costs1 returns and gross margins all being increased 25-50%

    Spatial and temporal dimensions of landscape fragmentation across the Brazilian Amazon

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    The Brazilian Amazon in the past decades has been suffering severe landscape alteration, mainly due to anthropogenic activities, such as road building and land clearing for agriculture. Using a high-resolution time series of land cover maps (classified as mature forest, non-forest, secondary forest) spanning from 1984 through 2011, and four uncorrelated fragmentation metrics (edge density, clumpiness index, area-weighted mean patch size and shape index), we examined the temporal and spatial dynamics of forest fragmentation in three study areas across the Brazilian Amazon (Manaus, Santarém and Machadinho d’Oeste), inside and outside conservation units. Moreover, we compared the impacts on the landscape of: (1) different land uses (e.g. cattle ranching, crop production), (2) occupation processes (spontaneous vs. planned settlements) and (3) implementation of conservation units. By 2010/2011, municipalities located along the Arc of Deforestation had more than 55% of the remaining mature forest strictly confined to conservation units. Further, the planned settlement showed a higher rate of forest loss, a more persistent increase in deforested areas and a higher relative incidence of deforestation inside conservation units. Distinct agricultural activities did not lead to significantly different landscape structures; the accessibility of the municipality showed greater influence in the degree of degradation of the landscapes. Even with a high proportion of the landscapes covered by conservation units, which showed a strong inhibitory effect on forest fragmentation, we show that dynamic agriculturally driven economic activities, in municipalities with extensive road development, led to more regularly shaped, heavily fragmented landscapes, with higher densities of forest edge
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