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Abbas Saidi, Bijan Rahmani, Rasol Ghaffari Rad,
Volume 7, Issue 4 (2-2021)
Abstract

Abstract:
Spatial planning as an alternative approach to sustainable development in geographical knowledge is based on a proper and appropriate understanding of space as a systematic phenomenon that has a fundamental role in guiding society towards the principles of sustainable development such that social and economic development and Improving the quality of life of each region depends on its spatial planning system.
The construction of dams is considered to be an interventionist measure in the environmental system, which may lead to positive or negative impacts. While these impacts can be recognized directly in all elements and phenomena that are related to the geographical space, they play an important role in the process of spatial development and "production of space". This article questions to what extent the construction of the Alavian dam affects the integrated spatial reorganization of rural settlements.
To investigate this, the Alavian reservoir dam in East Azarbaijan province (Iran) has been selected as a case study. The construction of the dam and the Alavian drainage network in the Maragheh and Bonab areas began in 1990 and ended in 1995 aiming to provide drinking, agricultural and industrial water as well as flood control. We hypothesized that the implementation of this project has caused a wide change in the structural and functional status of the spatial system as well as the changes in the environmental, socio-cultural and economy of the human settlements located at the margin of the reservoir. We studied such structural/functional changes in the spatial system of the Alavian dam and its irrigation network. It is presumed that "the role of the construction and Utilization of the dam and irrigation networks" has a great impact on "developments of the spatial system of rural settlements", mostly in social, economic and environmental.
In summary, we offer the following hypotheses:
  • In terms of segmentation, the top-down approach and structural approach, implementation and exploitation of the dam and Alavian irrigation network have not changed the spatial system of rural settlements within the scope of the project.
  • Spatial performance due to the construction of the dam and the Alavian irrigation network is different in structural and functional changes of the spatial system of rural settlements according to their dispersal and spatial distribution.
In this study, a descriptive-analytical method was used based on a comparative strategy. Within the framework of structural-functional scanning theory, four main criteria with 40 related indicators were selected to study the effects of reservoir dam construction and the irrigation network on all human settlements located in the geographical scope of the design. These criteria are considered to be the most important structural-functional components that are based on sustainable development.
All data (quantitative and qualitative) required for this research were collected using two methods of library studies and field survey and then analyzed. Data collection tools, including village and household questionnaires, interviews, focus group meetings, observation and field surveys, were collected through all data collection tools. The general questionnaire for all villages (27 villages) was completed in full format. The household size of the samples was calculated using a Cochran method with a confidence level of 95 percent for all 370 households. The household questionnaire was randomly filled out. The questionnaire of villages and households was completed according to the impact of the construction of the Alavian reservoir Dam separately and with a proportional distribution in the upstream and downstream villages.
To analyze the data, normality, correlation, Kruskal-Wallis, Mann-Whitney U and Kendall coefficient were performed using SPSS software.
This study presented an innovative way to evaluate the effects of construction of the dam and irrigation network on the variation of the spatial system of rural settlements in an integrated manner based on spatial paradigm. The findings of this research are the result of collaborative fieldwork to describe the relationship between dam construction and irrigation network and changes in the spatial system of villages. Spatial planning as a new, comprehensive and systematic approach to geographic knowledge can well support the theory of sustainable development. This approach is based on the harmonious and balanced development of the environmental-ecological, socio-cultural, economic and physical conditions of the spatial system.
To sum up, it can be said that observation of the spatial organization of the areas affected by the implementation of the dam and the Alavian irrigation network, as a result of uncompetitive development policies, is indicative of the imbalance and inequality in access to opportunities (such as access to agricultural water, increased agricultural production, increased income, etc.). Accordingly, due to lack of a Integrated and systematic approach based on the principles of spatial planning in the study and implementation of the Alavian Reservoir Dam, is not possible the conditions for positive change in rural settlements. It actually causes disarray, disunity and imbalance of the spatial system of the regions. In other words, is one of the most important reasons for failure of development projects in third world countries, ignoring the dimensions and structural-functional aspects of spatial systems. The project of construction of Alavian reservoir dam and its irrigation network can be a good example of such projects.

Tofigh Jasem Mohammad, Mohammad Rahmani, Komeil Abdi,
Volume 9, Issue 3 (12-2022)
Abstract

Changes in ground surface temperature in the city of Halle and its relationship with changes in the NDVI index
abstract
The temperature of the urban environment is one of the parameters that citizens are in contact with at any moment. Studies show that the global temperature is constantly increasing due to environmental changes. One of these parameters that affect the increase in temperature; The physical growth of the city and its consequent destruction and loss of vegetation. In this study, using Landsat satellite images for the years 2001, 2011 and 2021; and the implementation of the single-channel algorithm, the surface temperature of the ground in the Iraqi city of Halla was calculated and its changes were investigated and analyzed. On the other hand, the NDVI index was calculated as a vegetation index on the mentioned dates and its changes were analyzed with the temperature changes of the earth's surface. The general results of this research showed that the area of the city of Halle has doubled during the study period, and this has caused a decrease in the amount of vegetation and an increase in the temperature of the earth's surface. In the end, the correlation between the surface temperature and the NDVI index was calculated, which was equal to 46.92, 44.35 and 52.98% for the years 2001, 2011 and 2021, respectively. This issue shows the strong relationship between these two parameters and the effect of the reduction of vegetation on the increase in the temperature of the earth's surface.

Key words: Earth surface temperature, vegetation, NDVI, city growth, Halle city
 
Dr Masoud Moradi, Dr Mohammad Hosein Gholizadeh, Mr Meysam Rahmani,
Volume 10, Issue 2 (9-2023)
Abstract

Investigation of the Temporal and Spatial Variation of Maximum Soil Temperature in Iran

Extended Abstract
Introduction
The study of soil temperature in different depths of soil is important in climatology, hydrology, agrometeorology and water resource management. Different depths has a different temporal and spatial soil temperature variation. It represents the regional ground temperature regime. Furthermore, due to its rapid response to environmental changes, soil temperature is one of the most important indicators of climate change. The increase in soil temperature because of global warming can promotes disasters such as drought by increasing the water demand of agricultural products during the plant growth period. The increase in soil temperature also have a various consequences, include increasing evaporation from the soil surface, soil salinity in susceptible areas, which can lead to a decrease in soil yield and failure in plant growth. Therefore, knowledge of soil temperature changes in different environments is very important in climate studies. The aim of the current research is to analyze the spatial and temporal variations of soil temperature at different depths from five to 30cm of the ground and to investigate the existence of any kind of increasing or decreasing trend at different climates of Iran.
Methodology
Hourly soil temperature data (depths of 5, 10, 20 and 30 cm) were used in this research for the period of 1998-2017. The soil depth temperature is measured three times a day at 6:30 am, 12:30 pm, and 6:30 pm local time (3, 9, and 3 p.m. UTC). These data have been received for 150 synoptic stations of Iran on a daily basis from the Iran Meteorological Organization (IRIMO). IRIMO monitored the quality of soil temperature for data entry, data recording, and data reformatting errors. Data availability, discrepancies, errors, and outliers were identified during the second stage.
At the first step, temporal coefficient of variation were calculated for available soil temperature time series from five to 30 cm depths of each station. For this purpose, the average of three daily measurements of soil temperature was calculated and then the temporal coefficient of variation was obtained. In the next step, trend analysis of soil temperature has been investigated using the non-parametric Mann-Kendal test. The trend slope was calculated using Sen’s slope for each station in seasonal time scale. Trend analysis has been done for all three observations of the day.
Results and Discussion
The studied stations show significant spatial patterns in the temporal variability of soil temperature. In all four investigated depths, from five to 30 cm, the northwest parts of Iran, and some parts of Zagros and Alborz mountain ranges have high temporal coefficient of variation. In contrast, the stations located on the southern coasts and southern islands had the lowest temporal variability. In warm and cold seasons (summer and late autumn to mid-winter), the spatial changes of soil temperature at different depths are lower than spring and early autumn. However, in the warm period of the year, the soil temperature experiences lower spatial variations at different depths. Spring and autumn seasons, as the transition period from cold to warm and warm to cold seasons, show the most spatial temperature variations in Iran. Detected trends do not have significant differences among the three observations of the day. Soil temperature Trend analysis at different depths showed positive values for two seasons of summer and winter over most of the stations throughout Iran. Extreme trends are more frequent in the summertime of Zagros and Alborz mountainous regions, while in the winter season the stations located at the southern latitudes of Iran have experienced the most positive trends. In the summer season, higher trends with 99% confidence are more frequent in the mountainous areas. These positive trends in soil temperature have occurred in all studied depths. The negative trend at different depths is a distinct feature of the autumn season, which is significantly more prevalent than other seasons throughout Iran. The analysis of soil temperature trends in different depths shows that values above 1 degree Celsius often occur in 5 to 20 cm deeps. The increasing trend of soil temperature in winter shows a greater spatial expansion, which is indicate increasing annual minimum soil temperatures and the increasing trend of Iran's soil temperature.
Keywords: Soil Temperature, Spatiotemporal Variations, Man-Kendal Test, Sen's Slope, Iran

 

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