Suchergebnisse

Land degradation is most likely to affect the well being of people living in marginal regions. Agriculture is one of the major causes of land degradation. Land use decisions by farmers are influenced by the local environment and by external factors related to markets and policies. This thesis aims to develop, implement and evaluate a farm-level methodological approach of land degradation that integrates environmental and socio-economic factors potentially affecting land degradation, on the basis of three case studies in the southern EU. We developed methods combining remote sensing (RS) and GIS data with farm-level socio-economic surveys. We produced a "socio-ecological graph" based on aggregated biophysical and socio-economic metrics of land degradation for a sample of farms in Northern Greece. We explored the association between the financial condition of farms and land degradation. We analysed the fraction of direct subsidies in the standard gross margin of crops and livestock of our sample. It suggested that subsidies provided financial support to land uses associated with land degradation. In another study site, combining RS and farm survey data for a sample of sheep and goat farms in central Crete, we found that stocking rates were not associated with subsidies or land tenure. Rangeland degradation was not linked to stocking rates but with locations characterised by a specific geological substratum. Intensive livestock feeding suggested that farms were disconnected from rangeland vegetation, and were more exposed to market shocks. In a third study site, a typology of land uses in Chieti allowed us to identify possible degradation processes. Cereals were associated with erodible soils; olive farms were more prone to land abandonment; vine was unlikely to be a major source of erosion given the local topography. This study improved our understanding of the dynamics of farming H-E systems leading to land degradation. ; (GEOG 3) -- UCL, 2011

Land degradation is most likely to affect the well being of people living in marginal regions. Agriculture is one of the major causes of land degradation. Land use decisions by farmers are influenced by the local environment and by external factors related to markets and policies. This thesis aims to develop, implement and evaluate a farm-level methodological approach of land degradation that integrates environmental and socio-economic factors potentially affecting land degradation, on the basis of three case studies in the southern EU. We developed methods combining remote sensing (RS) and GIS data with farm-level socio-economic surveys. We produced a "socio-ecological graph" based on aggregated biophysical and socio-economic metrics of land degradation for a sample of farms in Northern Greece. We explored the association between the financial condition of farms and land degradation. We analysed the fraction of direct subsidies in the standard gross margin of crops and livestock of our sample. It suggested that subsidies provided financial support to land uses associated with land degradation. In another study site, combining RS and farm survey data for a sample of sheep and goat farms in central Crete, we found that stocking rates were not associated with subsidies or land tenure. Rangeland degradation was not linked to stocking rates but with locations characterised by a specific geological substratum. Intensive livestock feeding suggested that farms were disconnected from rangeland vegetation, and were more exposed to market shocks. In a third study site, a typology of land uses in Chieti allowed us to identify possible degradation processes. Cereals were associated with erodible soils; olive farms were more prone to land abandonment; vine was unlikely to be a major source of erosion given the local topography. This study improved our understanding of the dynamics of farming H-E systems leading to land degradation. ; (GEOG 3) -- UCL, 2011

Marginal and unstable environmental conditions force stockbreeders in drylands to develop adaptive strategies to ensure stability of production. In intensive market-oriented pastoral systems, the partial substitution of rangeland forage production by external feed increases the influence of commodity prices in stockbreeders' decisions, which become increasingly decoupled from environmental constraints. In Mediterranean countries of the European Union (EU), Common Agricultural Policy (CAP) subsidies also influence agricultural practices, potentially increasing environmental impacts. By modeling subsidy allocation to sheep and goat breeders in Crete, we showed that livestock subsidies for Less Favoured Areas (LFA) stimulated flock growth up to a point. By linking interviews of farmers to remote-sensing data in four village communities in central Crete, we tested statistically alternative hypotheses explaining the links between CAP subsidies, livestock-husbandry practices, and land degradation at the farm level. The flock growth stimulated by livestock subsidies was accompanied by the intensification of herd management, and decreasing yields and profits, with no statistical association to vegetation degradation. Farms with larger flocks became more sensitive to market fluctuations.

Marginal and unstable environmental conditions force stockbreeders in drylands to develop adaptive strategies to ensure stability of production. In intensive market-oriented pastoral systems, the partial substitution of rangeland forage production by external feed increases the influence of commodity prices in stockbreeders' decisions, which become increasingly decoupled from environmental constraints. In Mediterranean countries of the European Union (EU), Common Agricultural Policy (CAP) subsidies also influence agricultural practices, potentially increasing environmental impacts. By modeling subsidy allocation to sheep and goat breeders in Crete, we showed that livestock subsidies for Less Favoured Areas (LFA) stimulated flock growth up to a point. By linking interviews of farmers to remote-sensing data in four village communities in central Crete, we tested statistically alternative hypotheses explaining the links between CAP subsidies, livestock-husbandry practices, and land degradation at the farm level. The flock growth stimulated by livestock subsidies was accompanied by the intensification of herd management, and decreasing yields and profits, with no statistical association to vegetation degradation. Farms with larger flocks became more sensitive to market fluctuations.