جستجوی مقالات مرتبط با کلیدواژه « تصاویر لندست ETM+ » در نشریات گروه « جغرافیا »

Gavkhoni wetlands in terms of geography conditions, environmental and three factors hydrological , biological and ecological gives rise to the rarest wetland of iran in recent due to climatic conditions change, pollution and moving smooth has been subjectedchange and evolution .In this study has tried that by identification the process of change land use in this range in 17 years period as well as the changes the primary element of climate (temperature and precipitation) in synoptic stations of the Isfahan and Varzaneh, can be identified the desertification in the study area and in some way to help the environmental management this hole. Therefore at first the ETM satellite images area of study during the 1990, 1999 and 2006 prepared and by use of ENVI and GIS were analyzed.Untill obtained the information needed to evaluate quantitatively the changes. The results showed that due to the destruction of wetlands, related phenomena like variety and vegetation density and catchment area has declined .continuing to analyze desertification, view of climate first by using Thornthwaite method experimental procedure was evaluated evaporation and transpiration changes in Stations of Varzaneh and isfahan, finally were calculated the process of this change and temperature and precipitation by using Mann-Kendal and Sen's Estimator. The results showed components, temperature and evaporation and transpiration have significant rising trend in most months of the year, especially summer and autumn. On the other rainfull parameters in the two season, However, no clear trend , but it has fallen In fact, all these factors intensified the desertification of the area studied.