Tabriz urban growth simulation using CA-Markov models and multi-criteria decision

INTRODUCTIONToday, in developed and developing countries are experiencing rapid changes and growth in area and population. Essential for sustainable urban growth management and urban development planning, understanding patterns of urban growth is correct. Satellite remote sensing in conjunction with Geographic Information Systems (GIS) has been recognized as a powerful and effective tool in detecting land use and land cover changes (Jensen & Lulla, 1987).Satellite remote sensing is a potentially powerful means of monitoring land-use change at high temporal resolution and lower costs than those associated with the use of traditional methods and provides multi-spectral and multitemporal data that can be used to quantify the type, amount and location of land use and land cover changes(Jensen & Lulla, 1987).CA-Markov model is a dynamic model to simulate urban growth and land use changes that is obtained from a combination of automated cells and Markov chain (Norris, et al, 1998). Markov chain, spatial sequence of random processes in which the result of any process at any time, only next time it will depend on the outcome of the process. First, using Markov chain model, the possibility of changing land use map classes to each other in terms of probability matrix applications based on area changes between time t0 and t1 are calculated (Sang et al, 2011). Markov model output, literally, is the non-place where there is no knowledge of the geographical location of land uses. To predict the location of land at the time t1 automated cell techniques used with this model. In this study, we are using Landsat images Landsat TM5 and OLI and capabilities of IDRISI software and GIS, urban growth areas Tabriz changes during 30 years, from 1973 to 2013 is estimated.
METHODOLOGYIn this study, the tools available in IDRISI SELVA software and GIS functions to simulate changes in land use and urban growth Tabriz is used that includes three main stages:Tabriz is one of the major cities in Iran and the capital of East Azerbaijan province. The city, the country's third largest city after Tehran and Mashhad, Iran northwest region's largest city and business hub, communication, commercial, political, industrial, cultural and military recognized this area.
In this study, in order to identify and create land use maps of the city of Tabriz, images, Landsat sensors in the years 1973, 1993 and 2013 from the Geological Society of America (USGS) were obtained.
Land use map of the city of Tabriz to three major usages, urban areas, agricultural land and orchards and barren areas were created. Also in order to make land use suitability map that will be described below, from the map 1: 2000 and 1: 50000 city of Tabriz, the national mapping agency had been taken was used.
1.The transition probability matrix is calculated using Markov chain analysis: For this purpose, Landsat satellite images in 1993, 2003 and 2013, obtaining and using the techniques of site geology and America classified images, maps of urban development in the years to is produced.
2.The calculation of urban suitability map using Multi Criteria Evaluation and Analytical Hierarchy Process AHP
3.urban growth modeling with data collection: 1. urban areas Map 1993 as the base plan.2- suitability map urban growth in 2003.3- The transition probability matrix from 2003 to 1993 were combined by the operator, CA location
RESULTS and DISCUSSIONThe study area, Tabriz city is located northwest of Iran. Maps of land use and urban growth using satellite image processing techniques and supervised classification was created. The overall accuracy of the land use/cover maps for 1972, 2003 and 2013 were 82 %, 85 % and 90 %, respectively. The Kappa index for the 1972, 1990 and 2006 land use/cover maps were found to be , 76 %, 79 % and 89 %. The transfer matrix regions 2003 to 2013, 12 percent of rural to urban areas will become. Real and simulated map of 2013 is shown in Figure 1. The overall accuracy and Kappa index between actual and predicted Map 2013 respectively 91 and 81 respectively. The 2028 map was produced using ca-markov model. The map simulated by 2028, urban areas will grow 25 percent and from 11697 hectares to 14690 will increase..
CONCLUSION In the present study, Markov and CA- Markov models were helpful for predicting land use/cover changes and urban growth in 2013 and 2028. The results showed that the growth rate of the population growth in areas built in the city of Tabriz surpassed it. The gap between urban growth and population doubled in this period also shows that in this period, developing more horizontal than vertical form happened during this period, several areas of industrial, commercial and residential development was found. The outcomes of this research indicate that Landsat TM images can be effectively used for generating accurate land use/cover maps as the overall accuracies of all generated land cover map were found to be over 80 %. According to the results of the CA-Markov model, urban expansion will occur in the future. The combination of satellite remote sensing, GIS and Markov models provides useful information on land use/cover dynamics and change trends into the future which could help policy makers to make better decision for the future of the study area. The provided future projection could be effectively used for land use planning, decision making and land management, especially if its use is confined more to general trends than to specific land-use locations, where accuracy was lower. The predictive power of the CA-Markov model, especially in predicting the location of pixels, was not very high in this research but in general Markov models have shown the capability for the prediction of land cover/land use change trends