An ecological analysis of predominant land uses in the Brazilian Amazon
The land uses that now predominate in Brazil's Amazon Region are unlikely to produce sustainable yields. They also tend to close off potentially sustainable alternative uses. Cattle pasture - either productive or abandoned - now occupies most deforested land. Small farmers plant pasture after using...
| Autor principal: | Fearnside, Philip Martin |
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| Grau: | Artigo |
| Idioma: | English |
| Publicado em: |
The Environmentalist
2020
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| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/19600 |
| Resumo: |
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The land uses that now predominate in Brazil's Amazon Region are unlikely to produce sustainable yields. They also tend to close off potentially sustainable alternative uses. Cattle pasture - either productive or abandoned - now occupies most deforested land. Small farmers plant pasture after using the land for a year or two under annual crops, while large cattle ranches plant pasture directly after clearing. The principal motive for planting pasture is often its low cost and high effectiveness as a means of securing speculative land claims - not beef production. Pasture and cattle yields are low and, after use for about a decade, the planted grasses are out-competed by secondary forest species or inedible grasses. Depletion of available phosphorus in the soil is a major cause of yield decline; Brazil's relatively modest phosphorus deposits, virtually all of which are outside of Amazonia, make fertiliser use not feasible for the vast areas now rapidly being converted to pasture. Converting a substantial portion of Amazonia to pasture would have potential climatic effects. Areas that can be planted in annual and perennial crops are restrained by world markets, as well as by soil quality and Brazil's limited stocks of the inputs needed for intensive agriculture. Recent initiatives for "agricultural-ecological in Brazil's Amaoznian states could be a first step toward more rational land use. Immediate measures are needed to slow deforestation, to discourage unsustainable uses and to make sustainable alternatives profitable. © 1988 Science And Technology Letters. |