2 resultados para Mu Us sandy land
Resumo:
Accelerated soil erosion is an aspect of dryland degradation that is affected by repeated intense drought events and land management activities such as commercial livestock grazing. A soil stability index (SSI) that detects the erosion status and susceptibility of a landscape at the pixel level, i.e., stable, erosional, or depositional pixels, was derived from the spectral properties of an archived time series (from 1972 to 1997) of Landsat satellite data of a commercial ranch in northeastern Utah. The SSI was retrospectively validated with contemporary field measures of soil organic matter and erosion status that was surveyed by US federal land management agencies. Catastrophe theory provided the conceptual framework for retrospective assessment of the impact of commercial grazing and soil water availability on the SSI. The overall SSI trend was from an eroding landscape in the early drier 1970s towards stable conditions in the wetter mid-1980s and late 1990s. The landscape catastrophically shifted towards an extreme eroding state that was coincident with the “The Great North American Drought of 1988”. Periods of landscape stability and trajectories toward stability were coincident with extremely wet El Niño events. Commercial grazing had less correlation with soil stability than drought conditions. However, the landscape became more susceptible to erosion events under multiple droughts and grazing. Land managers now have nearly a year warning of El Niño and La Niña events and can adjust their management decisions according to predicted landscape erosion conditions.
Resumo:
A recent issue of EuroChoices (7:1) was devoted to a discussion of comparative US-EU rural development policies. This article discusses the concept of growth coalitions, well developed in urban literature but less so in rural literature. Some light is shed on the different positions of rural and environmental issues in EU and US policies. The agricultural lobby is the dominant actor in agricultural growth coalitions because it perceives land in terms of its exchange value. Environmental and rural development actors perceive land in terms of its use value and its contributions to quality of life: they form a rural development coalition, seeing the need to balance growth with quality of life, but they have less political power than the agricultural growth coalition. In the European context, rural and environmental agendas are linked to a multi-functional agricultural agenda allowing common ground between these two coalitions and greater visibility in the policy arena. In the US, rural interests and environmental groups are more often in opposition to agriculture. This reduces their political visibility and clout. The challenge is how to link the power of the agricultural growth coalitions with rural development coalitions to achieve a broader balance of concerns and a more effective rural development policy.