|Title||Alternatives to Slash-And-Burn in Forest-Based Fallow Systems of the Eastern Brazilian Amazon Region: Technology and Policy Options to Halt Ecological Degradation and Improve Rural Welfare. |
|Publication Type||Book Chapter |
|Year of Publication||2007 |
|Authors||Börner J, Denich M, Mendoza-Escalante A, Hedden-Dunkhorst B, Abreu Sá T |
|Book Title||Stability of Tropical Rainforest Margins- Linking Ecological, Economic and Social Constraints of Land Use and Conservation. |
|Pagination||331- 361 |
|City|| Berlin Heidelberg |
|Keywords||ASB, bio-economic modeling, bush chopper, fallow management, mulch, tax, yield insurance |
|Abstract||In many smallholder farming systems in the humid tropics, the slash-and-burn practice is used for land preparation. Increasing land-use intensity by shortening fallow periods often contributes to the degradation of the natural resource base of the fallow system, i.e. the fallow vegetation and soil. In the eastern Amazon region of Brazil, we therefore searched for ways to maintain the sustainability of the traditional fallow system and to adapt it to changing agro-ecological and economic conditions.
We identified two major agro-ecological constraints of the traditional fallow system with slash-and-burn: (1) high losses of nutrients and organic matter during the burn, and (2), if land-use intensity increases, fallow regeneration capacity declines.
As alternatives to slash-and-burn, we studied modifications to those practices recognized to be harmful to the ecological sustainability of the fallow system, i.e. mulching for the management of soil organic matter and fire-free land clearing with bush choppers to transform fallow vegetation into mulch. Mulching allows extending the cropping period, planting crops off-season, and modifying crop rotations. Additionally, biomass and nutrient accumulation of degraded fallow vegetation can be improved by enrichment plantings using fast-growing leguminous tree species.
Our socio-economic analysis focused on the implications of technology change on income and land-cover change at farm and field levels. Based on farm-household data collected from 270 randomly selected households, a farm-household level bio-economic model was developed to analyze the consequences of improved access to mechanized plowing and mechanical mulching for typical smallholdings in the study area.