Journal of Spatial Analysis

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Today slum refers to those areas of the city which are not necessarily situated at the corners of the city, but to those which are in margins from economic, social, cultural, and other urban life aspects, that has formed a settlement in which the least living-supplies of healthy water, electricity and gas, transportation system and a clean environment suffice their lives. This type of settlement is due to the asymmetry and commonality of features and conditions of living in the main parts of the city. And generally indicate the low level of living conditions in comparison with the average standards in the main city specifically, and also in living conditions in cities as a whole. On the other hand, informal settlement refers to the discordance of settlement with the approved regulations of governmental organizations and particularly of municipalities. Those areas which are situated outside the servicing scope of the general and governmental organizations such as electricity, gas, and telecommunications offices, along with municipalities accompany various phenomena such as urban poverty, poor housing, immigration from countryside to cities, environment pollution, unhealthy environments and etc.

            In Iran, slum began in the 30s (solar calendar) with the immigration of village dwellers to the cities, and after a decade, it was prospered due to land reforms and economic-social policies of the day, a growing increase which has never stopped since. Slum or informal settlement in the outer parts of the cities is not just a physical notion but is an outcome of the macro structural factors in economic, social, cultural, and political aspects in a national or regional scope. The reasons for this phenomena vary which can differ from one place to another. Nevertheless immigration is one of the main reasons for slum settlements. It can simultaneously play two roles; it can be a solution to demographic crises. It leads the surplus population out of the region and accordingly the human power is directed where is needed most. It balances the structural asymmetries of population and by reducing the development imbalances in different regions result in the betterment of the status quo. And on the other hand, it might be possible that by immigration of the human power, the economic equilibrium between the source and destination community would be disturbed, and by having a community without any human power, it generates complex social and cultural situations; which all in all leads to a congested crowd overpopulating specific big cities and regions.  In this way, it brings about problems in servicing and efficient regulation of issues and thus be regarded as a disturbing element of development and mutual understanding. The investigated region has been exposed to the crises of immigration and slum settlements recently, so much so that based on the population and housing census of 2006, population growth rate of Shahriar rose by a far distance from other cities to 8.7 percent. Thus, this research was conducted to investigate the elements of immigration and slum dwelling in Shahriar city. And it aims to answer these questions:

1. How social, economic, and demographic factors influence the slum settlements of those who have migrated to this city?
2. How is the local dispersion in Shahriar?

On this basis, with the researches and investigations conducted at the outset of the study, district 2 was selected as a fit choice out of the three districts of 1, 2, and 3 which settled slums. Since all the locals were not slums in this specific districts, with proper investigation the slum areas were identified which had a high rate of immigration; with whom interviews were ran and questionnaires distributed. To this end, by following Cochran formula, 200 people were selected as samples through cluster random sampling out of the statistical community. To analyze data, descriptive statistical methods such as central index, dispersion and inferential statistics like Chi-square, Wilcoxon and Friedman tests were utilized.

The results of the  study indicates that the slum in Shahriar are situated in the old and cheap sections of the three districts of 1, 2, and 3. Also, after a detailed examination it was proved that Shamloo local in district 2 is more suitable than the other ones. On the other hand, by investigating the economic factors (such as job opportunities and income) it was indicated that immigration is very important from the aspect of providing job opportunities. Secondly, social factors are more important in slum settlements issues. For instance, one can refer to urban and welfare facilities, educational facilities, health and recreation facilities are all social factors. On the other hand, those people who have migrated due to pursuing education, higher level of welfare, better facilities etc. are all below 30 years old. Based on the findings of this research, families were not significantly changed after immigration in comparison with the period before it, but it is a vital element in three membered families in times of immigration. All has been done to meet the financial needs of the family. Therefore, one can claim that most immigrations to slum areas have been due to economic and social deficiencies of the source society.

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Drought is one of the most complex and unknown natural phenomena that causes a periodic water crisis in the affected areas. Increasing water demand on the one hand and the experience of droughts in the province in recent years have led to the water crisis. Knowing the drought is one of the requirements for water crisis management. The purpose of this study was to analyze the trend of the SPI drought index in Isfahan province using nonparametric Sen’s slope test, Pettitt’s change point test and Man-Kendall test. From the monthly climatic data of 10 synoptic stations with a length of 27 years (1990-2017) for time series    The results of applying  Mann–Kendall  and  Sen’s slope tests based on SPI Index for  9, 12, 18, 24 and 48 month time periods, shows drought trend is significantly increasing for all stations out of Ardestan, Esfahan and  Shahreza  stations. In Ardestan station, the drought trend is significantly decreasing for 9, 12, 18, 24 and 48   month time periods and in Isahan station, the drought trend is significantly decreasing for only 48 month time period, and in Shahreza statition, the drought trend is significantly increasingonly for only 18 month time period.
  Despite all stations, the drought trend for one month time period, is significantly increasing just  for Naein station.
   In addition, applying Mann–Kendall test  on monthly rainfall for all station  shows downward but  not significant trend.
   Finally, applying Pettitt’s change point test based on SPI  Index  for 9, 12, 18, 24 and 48   month time periods indicates  the existence of a  significant change point. For same periods we observe  no change point for the monthly rainfall  in all stations.
   In summation, considering the SPI drought index, about 59% of  all stations show significant downward trend bases on Mann-Kendall test and 60% of  all stations show significant slope  based on Sen's slope test and 75% of  all stations show significant change point based on Pettitt's test. In general, for drought analysis using different time periods for the SPI index, in a short time period. (such as 6 months) drought is more frequent but shorter, and as the period increases the duration of drought also increases but frequency decreases. All together, we are facing  a water crisis in Isfahan province and  we must manage water demand  very urgently.

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Introduction
Dust storms as one of the environmental hazards of the arid regions of the globe, including the southern, southwestern, eastern and central parts of Iran, has caused many environmental problems that confirm the need for studying and crisis managing its in scientific and executive congresses. Therefore, the present study attempts to evaluate the effects of climate elements on temperature, precipitation, humidity, evapotranspiration and vegetation index on the frequency of dust storms in Yazd province during the period of 5 years (2009-2014).
 
Data and Methodology
So, after determining the synoptic stations of the area, the dust data were extracted based on the code of the present weather phenomena and the values of the climatic elements. In the next step, their spatial zonation was determined through the interpolation method. Then, using the MODIS images, EVI index data were calculated according to the principle of time matching. Finally, a variety of simple and multiple regression models were fitted to estimate the occurrence frequency of dust, and the most appropriate relationships with higher preference values were reported.
 
Findings and Conclusions
The results showed that there was a significant relationship between the total dust with evapotranspiration and relative humidity with a R square of 0.973 and 0.614 and the standard deviation of 24.104 and 92.477 at sig. level of 99% and 95%. Also, there is the maximum significant relation between external dust with evapotranspiration and relative humidity with a R square 0.968 and 0.621, and the standard deviation was estimated to be 0.173 and 75.427 at sig. level of 99% and 95%, respectively. Internal dusts with evapotranspiration and maximum temperature with a R square of 0.770 and 0.377 and standard deviation of 15.1751 and 64.22 have a significant relationship with sig. level of 95%. The results of the total, external and internal dust storms with climatic elements and vegetation cover showed a significant correlation with the R square of 0.994, 0.988 and 0.956 and the standard error of estimation of 18.13713, 24.2555551 and 10.49989 at sig. level of 99% and 95%, respectively, which indicates the systematic function of climatic elements and vegetation cover in the occurrence of dust.

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Real-time detection of forest fire using NOAA/AVHRR data
Study area :(Kayamaki Wildlife Refuge)
 
Extended Abstract
Introduction
Land and forest fires are one of the most common problems in the world that cause various disturbances in forest and land efficiency. Real-time fire detection is crucial to prevent large-scale casualties. In order to identify early fire in areas where there is a high risk of fire, it is necessary to monitor these areas regularly. Forest monitoring is a technique used to detect fires in the past using traditional techniques such as surveillance, helicopter and aircraft. Today, satellite imagery is one of the most imperative and effective tools for detecting active fires in the world.
Materials and Methods
In this study, NOAA/AVHRR images were used for fire detection and MODIS products were applied for evaluation and validation.
Fire Detection Algorithms
There are several algorithms for detecting fires using satellite imagery. In this study, 3 algorithms of Giglio, extended and IGPP were used. The selection of these algorithms was due to the extensive background research in most of the previous studies that used them and the results of these algorithms, especially the IGPP, were far more than other algorithms.
Giglio Algorithm
Giglio et al., (1999) criticized Arino and Melinott (1993) threshold as too high for certain regions of the world such as tropical rain forests, temperate climates and marshes where the air temperature for small fires (100 m³) is usually between 308 and 314 degrees Kelvin. They believed that the smaller fires were not fully recognized by Arino and Melinott (1993) thresholds. They concluded that in suburban forests 60% of fires had temperatures below 320K of which 70% were in rainforests and 85% happened in the Savanna. Thus, the threshold cannot be applied on a large scale and it is only applicable for a regional scale.
IGBP Algorithm
The IGBP fire detection algorithm is implemented in two steps. The first step is the threshold test in which a pixel in micrometers (11.03 μm) minus the band 4 is greater than 8 degrees Kelvin, the desired pixel being considered as a potential fire pixel. Band 3 (3.9 μm) exceeds 311 K, and band 3 illumination temperature is 3.9.
Developed Algorithm
This algorithm is used to detect small and large fires (both at night and day).
 
Interpretation of the Results
After selecting fire detection algorithms, pre-processing (geometric, radiometric and atmospheric corrections), processing (applying fire relationships and fire formulas for fire detection) and post-processing (evaluating and validating the results), the fires were identified by the fire algorithms (images). Final results of fires identified for 2016 and 2017 (for 4 days) by fire algorithms indicate that fires identified by Giglio algorithm were 22 cases, those by IGPP algorithm were 27 cases and the ones by the developed algorithm were 15 cases. For this reason, the IGPP algorithm can be taken as the most appropriate algorithm in this study for fire detection using satellite imagery.
Evaluation of fires identified through MODIS products
To evaluate identified fires, after recognizing them with relevant algorithms, we used MODIS products for their evaluation (due to the lack of ground data on the days studied for evaluation). MODIS products were obtained from sites where the location of each fire was reported. For the evaluation of identified fires based on fire detection algorithms with MODIS products, 10 fire occurrences were used. The evaluation results express that out of 10 fires only 7 fires were recognized by the algorithms of MODIS products. 5 fire events were identified by Giglio algorithm (from 7 fires), 6 fires from IGBP (out of 7 fires), and 3 fire events from 7 extended algorithm were selected as fire pixels.
Comparison of the implications of the fire algorithms
The implications of fire occurrence algorithms indicate that the IGBP algorithm with 6 fires (out of 7 tested fires with error rate of 14% and with the number of fires detected (86%)), Giglio algorithm with 5 fires (out of 7 tested fires, with error rate of 28% and with the number of fires (72%)) and the developed algorithm with 3 fires (out of 7 fires tested with an error rate of 57% and with fire rate of 43%) have been identified. Therefore, it is concluded that the IGBP is the most appropriate algorithm for real-time fire detection, followed by Giglio and the developed algorithm in second and third orders, respectively.
Keywords:Real Time Fire Detection, Fire Algorithms, NOAA/AVHRR, Kiamaki Wildlife Refuge.
 

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Explanation of the subject: The annual drought phenomenon, by affecting economic, social and environmental issues, leads to the vulnerability of urban and rural households and the instability of their livelihoods. Yazd is one of the provinces with drought. Consecutive droughts in the province necessitate integrated management and community adaptation in times of drought.
Method: Taking into account the length of the statistical period of 20 years and to obtain the results with a high level of confidence, the main data of the census documents that have been compiled for the development of cities and villages have been used. By analyzing the main components of several factors, it was selected as the main components. By calculating the standard precipitation index in the arid region, the driest year was determined and by calculating the weighted average of their correlation index with the main components of socio-economic and ecological environment based on appropriate statistical inference. At the end of the year, the effect of drought on different dimensions was presented by step-by-step linear regression, analysis and communication between them to adapt and resilience of individuals in society.
 According to the general results, one of the most important economic and dry economic losses is the annual income of the villagers, which can be due to the decrease in the area under cultivation and production of the main agricultural products. In the social sector, people with knowledge and awareness should increase their adaptive capacity to the occurrence of drought, in order to reduce the vulnerability of social issues to the phenomenon of drought. The results show that unemployment insurance has increased following the drought. The main reason for this is the unemployment of farmers affected by drought, so changing jobs along with temporary migration or the production of handicrafts, etc. can increase the relative income of households at the time of occurrence and prevent unemployment in these conditions. Increasing unemployment will cause other social harms such as poverty, declining health, increasing disease, and reducing judicial and social security. According to the results, one of the components that has established a high standard of rainfall during the drought year is the theft of livestock, which shows a decrease in the social security of the community. People in the study community increase their adaptability to the annual drought by increasing breeding work, such as rangeland improvement, rainfall collection, biological improvement, afforestation, and irrigation reform.