Assessing the Trend of Landcover Changes in Asaloyeh - Shirino Coastline Applying LCM Model

Population growth, development of residential areas, as well as man-made land use, are causing landcover change. Shorelines are more sensitive to landcover change. Therefore, the current study aims to evaluate the trend of landcover changes in the southeast of Bushehr province from Asaloyeh city to Shirino village. The study used Landsat satellite images from the 1990, 2000, 2010 and 2019 and the LCM model to assess the trend of landcover change. The procedure is that first the landcover maps are prepared and then the process of land use change changes, changes in other landcovers to man-made areas and also the coastline change process is evaluated. The assessment of the change indicates that the use of man-made areas has had significant changes in a period from 1990 to 2019 under the influence of the development of economic activities and in parallel with the development of residential areas, refineries, as well as other facilities related to the Gas Company. Depending on the location of the study area and the type of anthropogenic, man-made use (refineries and other facilities and infrastructure related to the gas company), land-use changes mostly direct to coastline. Therefore, 11.2 km² of the sea has been changed to an arid area during a 29-year period. Besides, the development of economic activities and job creation, residential areas in Assaluyeh and Nakhl have experienced significant growth, and this development has further changed the use of sandy lands to the construction of man-made areas.
Extended Abstract
1-Introduction
Urban growth has been accompanied by changes in land use and increased urban activity, which is the result of population growth and economic development. In fact, the horizontal and unplanned expansion of cities with increasing population and growing urbanization leads to land scarcity, changes of adjacent lands, and unprincipled and unplanned use of land and change of land uses. Land use change affects the amount of land demand for agricultural, forestry, industrial, residential, tourism, and landscape diversity and natural areas. One of the most important changes is the change in urban areas. Today, urbanization has become one of the changing factors on the earth surface. Therefore, knowledge of the types of land surface coverings and human activities in its different parts and in other words how to use the land as a basic information for different programs is of special importance which causes possible future developments. Meanwhile, coastlines are more sensitive to land use change, so the present study aims to evaluate the trend of land use change in the southeast of Bushehr province from Asaloyeh city to Shirino.
2-Materials and Methods
In order to achieve the desired goals, Landsat satellite images and a 30-meter-high digital model have been used in this study. In the first step, the desired images are prepared; given that the purpose of this study is to evaluate land use changes from 1990 to 2019. In the second stage, land use maps related to the studied years have been prepared. In order to prepare a land use map in ENVI software, first radiometric and atmospheric corrections have been applied to the images and Then, using the maximum probability method and in 5 classes (man-made use, vegetation use, pasture and barren land use, sand use and water zone use), the desired maps have been prepared. In the third step, IDRISI software and LCM model were used to analyze the changes. Therefore, the trend of land use change from 1990 to 2000, from 2000 to 2010, from 2010 to 2019, as well as from 1990 to 2019 has been evaluated.
3-Results and Discussion
The results show that land use, especially man-made use of the study area, has undergone significant changes from 1990 to 2019, so that the use of man-made areas has grown by 25.9 km² over a period of 29 years. The results of the analysis of changes in other uses of human-made areas indicate that during the years 1990 to 2019, 0.6 km² of vegetation use, 5.3 km² of use of pastures and barren lands, 11.6 km² of sand use and 11.2 km² of sea has been converted to man-made areas. Spatial analysis of the changes also indicates that most of the changes have taken place near the cities of Asaloyeh, Nakhl and the coastal strip. The study also assessed the trend of coastline changes. The findings reveal that between 1990 and 2000, 1 km² from sea to land and 0.36 square kilometers from land to sea. Between 2000 and 2010, 8.5 square kilometers of sea became land and 0.1 km²of land became sea. Between 2010 and 2019, 1.7 km² of land has been converted from land to land and 0.3 km² from land to sea, according to which from 1990 to 2019, 11.2 km² from sea to land and 0.8 km² of land has been turned into a sea.
4-Conclusion
The assessment of the change indicates that during the years 1990 to 2019, under the influence of the development of economic activities and in parallel with the development of residential areas, refineries and other facilities related to the oil company, the use of man-made areas underwent significant changes. Depending on the location of the study area and the type of man-made use (refineries and other facilities and infrastructure related to the oil company), the trend of land use changes has been more towards the coastal strip leading to the transformation of the 11.2 km² area from the sea to land during this 29-year period. Furthermore, due to the development of economic activities and job creation, residential areas in Assaluyeh and Nakhl have experienced significant growth, and this development has further changed the use of sandy lands to the construction of man-made area.