تحليل ساختار و عملكرد مراتع با استفاده از داده هاي سنجش از راه دور و روش زميني LFA

چكيده انگليسي :

114 Analysing rangeland function and structure using remote sensing data and field based LFA method Fatemeh Jafari Jafari f12@gmail com Data of submission 21 9 2013 Department of Natural Resources Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Reza Jafari reza jafari@cc iut ac irSupervisor Hussien Bashari hbashari@cc iut ac irAbstractAssessing the structure and functionality of rangeland is required to detect early changes in the ecosystemand assist managers to evaluate the effects of their management practices The both field methods and remotesensing indices can be used to assess rangeland functionality Rangeland ecosystems are formed by manyvegetation patches with different ability to conserve vital resources such as water and nutrients LandscapeFunction Analysis LFA is a relatively new method to assess the functionality of rangeland ecosystems byassessing soil stability nutrient cycling and infiltration of a particular site derived from 11 soil surfaceindicators Assessing rangeland functionality by remote sensing data also decrease the cost of assessmentprocedures and measurements error and enhance the accuracy of the results This study aimed to evaluate thefunctionality of Steppe and Semi Steppe rangelands in Isfahan province using field and remote sensingapproaches Three sites in Steppe rangelands of Shahreza with very poor condition and also 3 4 and 7 siteswith very poor poor and moderate condition respectively in Semi Steppe rangeland of Aghcheh wereselected One transect was established directly downslope in each site randomly and a continuous record ofall patch inter patches including their names lengths and widths were recorded Also in all patches 11indicators of soil surface characteristics were measured with three replications and their status were scoredaccording to LFA method and then the functionality indices of all sites including soil stability infiltrationand nutrient cycling were measured accordingly The landscape functions of studied area were also assessedby some remote sensing indices including leakiness index LI Weighted Mean Patch Size WMPS index Lacunarity index and proximity index Landsat 5 TM sensor satellite images obtained at 1 6 2009 was usedto calculate the indices Geometric corrections were applied to the images and studied areas in Aghcheh andShareza were divided into 12 sub basins with size of 6995 hectares and 4 sub basins with size of 16067hectares respectively The remote sensing indices were calculated in all sub basins According to theanalytical analysis structural characteristics number of patches patch length patch area index landscapeorganization index and functional indices infiltration stability and nutrient cycling status variedsignificantly 0 05 between rangeland sites with moderate and very poor condition in Semi Steppe sites The changes of these structural and functional characteristics were not significant between range sites withmoderate and poor and poor and very poor range condition The regression analysis revealed that the valuesof LI index had a negative linear relationship with NDVI values In other words LI values decrease with

جعفري، فاطمه

تحليل ساختار و عملكرد مراتع با استفاده از داده هاي سنجش از راه دور و روش زميني LFA

استپي , نيمه استپي , مرتع , تجزيه و تحليل عملكرد چشم انداز , Landsat TM , LI , WMPS , Lacunarity , proximity