Emad Zakeri; Hamidreza karimzadeh; Seyed Alireza Mousavi
Abstract
Cover-management factor (C) is one of the most important influential factor on soil erosion using the Revised Universal Soil Loss Equation (RUSLE) model. C-factor is challenging to determine based on the proposed procedures due to lack of accurate information. Vegetation cover map can be used to estimate ...
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Cover-management factor (C) is one of the most important influential factor on soil erosion using the Revised Universal Soil Loss Equation (RUSLE) model. C-factor is challenging to determine based on the proposed procedures due to lack of accurate information. Vegetation cover map can be used to estimate C-factor, but preparing a suitable mapping of vegetation cover is challenging in many situations. Therefore, in this study vegetation cover map was prepared and compared using the k Nearest Neighbor (k-NN) algorithm, linear regression (LR) and linear stepwise regression (LSR) in the study area. In regression methods, 17 vegetation and environmental indices were prepared and their relationships were investigated. The results of comparing the three methods showed that the k-NN method has better results than other regression methods due to its highest overall accuracy (83.3%) and kappa coefficient (75.9%) therefore, it was used to produce C-factor map. Results showed that the k-NN was very promising for mapping vegetation canopy cover in the arid and semi-arid areas. The results showed that among vegetation indices NDVI had the highest correlation (0.82) with percentage vegetation cover. Also, in the k-NN method, the Euclidean distance metrics in k = 9 has better results than the other two Fuzzy and Mahalanobis distances and can be used to estimation of vegetation cover map.
Emad Zakeri; Hamidreza karimzadeh; Seyed Alireza Mousavi; mohammad ghorbani
Abstract
Rangelands provide a diverse array of vital services that pertain to human life. But market failure to consider the value of these ecosystem services has disturbed provision of many ecosystem services. In this study the economic value of water conservation functions by Arnaveh basin located in northwestern ...
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Rangelands provide a diverse array of vital services that pertain to human life. But market failure to consider the value of these ecosystem services has disturbed provision of many ecosystem services. In this study the economic value of water conservation functions by Arnaveh basin located in northwestern Iran was estimated. Rainfall-runoff simulation was carried out by using Curve Number (CN) method. Also by means of Replacement Cost method the value of the hydrological services were quantified. The role of vegetation cover in water conservation was estimated by comparing the surface runoff under current condition and uncovered soil conditions. Moreover the role of rangelands on water retention and surface runoff reduction by devising three more hypothetical scenarios and then the effects of land use changes associated with these scenarios on rainfall-runoff rate of the region were compared. Results showed that the role of rangelands vegetation cover in water conservation and surface runoff reduction was 7.19×106 m3, with the economic value of 123×109 IRR. Also, the results of a comparing between 3 hypothetical scenarios and current conditions showed that, under the case of scenario one which assumes that the entire of rangelands area is becoming to rain-fed farming, total outflow would be in the maximum amount and the most negative effects will accrue. Also the scenarios of improvement of vegetation cover to 25-50 percent has the most positive effects (1.95×106 m3 yr-1 decrease) on water retention. The results of this study could help decision-makers in selecting appropriate and economically feasible development strategies.
Emad Zakeri; Mahdi Ghorbani; Ali Bozorgmehr; Hojatollah Rabani Nasab
Abstract
Current nomad settlement programs seek improving the quality of nomads’ life as their ultimate goal. However, it seems some of these programs failed due to some problems such as socio- economic problems that appear after settlement or due to the lack of proper preliminary studies before the implementation. ...
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Current nomad settlement programs seek improving the quality of nomads’ life as their ultimate goal. However, it seems some of these programs failed due to some problems such as socio- economic problems that appear after settlement or due to the lack of proper preliminary studies before the implementation. Nomad settlement program in Northern Khorasan is not an exception; therefore, identification and prioritization of problems before implementation of the program in Northern Khorasan is essential for better planning. The required data to identify and prioritize nomad settlement problems and to plan for their proper settlement were gathered through a questionnaire including the criteria and sub-criteria as well as options to solve extant challenges. The questionaire then was completed by experts and analyzed by using the analytic hierarchy process in Expert Choice2000. The results showed that cultural and social management and planning factors with coefficients of (0.433) and (0.314), respectively left the greatest influence on the failure of relevant projects in North Khorasan province. Therefore; the reform of the administrative and planning system as an important solution to problems related to the management and planning criteria and increasing the nomads’ participation in planning and management as an important solution to problems related to social and cultural criteria were assessed in present study.
