To identify critical sediment sources in large catchments, using easily available terrain information at a regionalscale, a methodology was developed to obtain a qualitative assessment necessary for environmental management.Fargas et al method was employed in the research. The study was carried out in one of the sub-basins of Hableh Roodbasin called Dehnamak in the arid and semiarid climate of ...

This article describes an applicationof small area estimation in a survey conducted in the Rathbun Lake Watershed in Iowa (USA). From a sample of 183 plots in the watershed, erosion from four sources as well as total erosion are estimated for 61 small areas within the study region. Information on land cover and topography from GIS coverages are used to create plot-level covariates for the regre...

Land degradation is one of the significant issues the human beings are confronted with, which has become a bottleneck of restricting the sustainable development of the regional society and economy. In order to ascertain the root causes contributed to the land degradation and characteristics of land degradation, Bijiang watershed, the most important Lead-Zinc mine area of Lanping county of Yunna...

We raise the problem of the minorities' survival in the presence of positive network externalities. We rely on the example of thematic clubs to illustrate why and in which circumstances such survival problems might appear, …rst considering the case of simple network externalities and then the case of cross network externalities. Sonnac and Skerdilajda Zanaj for their comments and suggestions.

Desertification is one of the major issues threatening human communities. Manymethods have been developed for assessment and mapping of desertification hazards. In thisresearch, multi-criteria evaluation method was used to investigate desertification process inTrouti watershed, Golestan Province, Iran. At the first step, major desertification factors weredetermined by doing field surveys. They ...