نوع مقاله : مقاله پژوهشی
موضوعات
عنوان مقاله English
نویسندگان English
Aim: Iran's geographical location has caused a large part of its regions to include arid and semi-arid regions. Given the high sensitivity of these areas to environmental degradation, the spread of desertification is considered one of the most important environmental hazards in these areas. Given the importance of the issue, this study aims to identify areas at risk of desertification in Qom province
Materials & Methods: In this research, Google Earth images, MODIS satellite images, CHIRPS, and 30-meter digital elevation model have been used as the most important research data. The most important tools used in the research include Google Earth Engine, ArcGIS, and Super Decisions. Also, NDVI, weighted linear combination (WLC), and analytical network (ANP) models have been used. The general method of work in this research has been based on 9 parameters (vegetation density, dust concentration, average precipitation, average temperature, aridity coefficient, elevation, slope, distance from main road, and distance from urban areas), as well as the combined WLC-ANP model. Areas vulnerable to desertification risk have been identified.
Finding: Based on the results, a large part of the central areas of Qom province is affected by low vegetation density, high dust concentration, high aridity coefficient, low average rainfall, high temperature, low altitude, and proximity to urban areas and main roads. It has a very high potential for vulnerability to desertification.
Conclusion: The overall results of this study have shown that the central regions of Qom province are highly sensitive to the risk of desertification, so special attention should be paid to this issue in environmental planning, especially in plans related to land use changes.
Innovation: The innovation of this research is the combined use of Google Earth Engine and geomorphological parameters, and only areas with an NDVI coefficient greater than 0.1 were selected as study areas. The results of this research can be used in various environmental planning.
کلیدواژهها English
Extended Abstract
1. Introduction
Desertification refers to the degradation of land in arid, semi-arid, and semi-humid areas, which is influenced by various human and natural factors and is often considered a significant threat to human societies. The phenomenon of desertification today affects many areas, particularly in arid and semi-arid regions. Arid and semi-arid areas are highly sensitive to the destruction of vegetation cover. In these areas, various natural factors, such as climate change and drought, as well as human factors, like land use changes, can contribute to the destruction of vegetation cover and the spread of desertification. The importance of the issue of desertification has made it a significant challenge for many countries. Given that approximately two-thirds of Iran's territory is comprised of arid and semi-arid areas, it can be said that a significant portion of Iran's land is vulnerable to desertification. In fact, Iran's location has caused a large part of its central and eastern regions to be at risk of desertification. Among the areas exposed to this phenomenon is Qom province. The climatic conditions of Qom province and its human activities have put pressure on natural resources, leading to the destruction of pastures and, consequently, the spread of desertification. Given that the risk of desertification is one of the leading threats in Qom province, it is crucial to study and investigate this phenomenon in detail and identify areas vulnerable to its spread, which is addressed in this research.
2. Materials and Methods
In this study, Google Earth images, MODIS satellite images, CHIRPS, and a 30-meter digital elevation model were utilized as the primary research data. The most important tools used in the study included the Google Earth Engine system (to prepare maps of dust concentration, vegetation density, average temperature, average precipitation, and aridity coefficient), ArcGIS (to prepare the desired maps), and Super Decisions (weighting the parameters). In this study, various indices were also employed, the most important of which were the AOD index (used to create the dust concentration map of the region) and the NDVI index (used to create the vegetation density map of the region). Additionally, this study employed the integrated WLC-ANP model to create the final map of desertification-prone areas. Considering the desired objectives, this study was carried out in three general stages. In the first stage, the parameters were selected, and the main study area was determined. In the second stage, information layers related to the desired parameters were prepared. In the third stage, using the integrated ANP-WLC model, the final map of areas vulnerable to desertification risk was prepared.
3. Results and Discussion
The geographical location of Iran has led to a significant portion of its regions being arid and semi-arid. Given the high sensitivity of arid and semi-arid regions to environmental degradation, the loss of vegetation cover and the spread of desertification are considered one of the most significant environmental hazards in these regions. Among the regions facing the challenge of desertification is Qom province. The results of this study have shown that a significant portion of this province consists of land without vegetation cover. In fact, the results obtained from the NDVI coefficient have shown that a large part of the eastern half of Qom Province lacks vegetation cover, and as a result, only parts of Qom Province with an NDVI coefficient of more than 0.1 have been studied. The results obtained from the evaluation of climatic parameters have shown that due to the significant difference in altitude between the western regions and the central and eastern regions of Qom province, in a general trend, the western regions have more precipitation, lower temperature, lower aridity coefficient, and lower dust concentration coefficient than the central and eastern regions of this province. Due to climatic differences, topographical variations, and varying levels of human activity in the studied area, the potential for desertification also varies across different regions of Qom Province.
4. Conclusions
The results of this study have shown that a large part of the central regions of Qom Province has a very high potential for desertification due to low vegetation density, high dust concentration, a high aridity coefficient, low average rainfall, high temperatures, low altitude, and proximity to urban areas and main roads. Additionally, the western regions of this province have a low potential for desertification due to their location within the mountain unit, low impact of human activities, higher rainfall, and lower temperatures compared to the central and eastern regions of Qom province, as well as their high altitude and low dust concentration. The overall results of this study indicate that the central regions of Qom province are highly susceptible to desertification, so special attention should be paid to this issue in environmental planning, particularly in land-use change plans. Additionally, it is possible to provide solutions to increase vegetation density, particularly in sandy areas and in areas without vegetation adjacent to the cities of Qom province.
5. Acknowledgment & Funding
The manuscript did not receive a grant from any organization.
6. Conflict of Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
