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Showing 8 results for Land Use Change

Dariush Jahanshahi, Seyed Nematollah Mousavi, Ayatollah Karami,
Volume 0, Issue 0 (1-2024)
Abstract


 

Volume 11, Issue 1 (3-2007)
Abstract

Analysis of land use changes in the areas around of large dams specially in the top of dam building and hydrology network is the main subject to evaluate environmentally effects. In this paper, analysis of dam effects in Sattarkhan Dam of Ahar city has been studied. Due to this dam supporting water in order to using in agriculture, drinking water activities and to support water for lands under dam construction areas, have considerable effects in the environment. In this study using results of reorganization of changed areas and unchanged areas from satellite images and to combine them with building and other equipments, rate and extent al effects analyzed in land use were determined. The results of this research in GIS environment as thematic maps presented, indicate that in covered Sattarkhan Dam have two direct and indirect effects in its around. Th/e changes of grounds and agricultural levels to building and water surface is the directs of very high injured and changes of dry farm land and bear land to gardens developments of urban areas is the indirect effects and has low and very high injured indexes respectively.
F. Khormali, K. Nabiollahi,
Volume 11, Issue 3 (7-2009)
Abstract

The present study was carried out in Kharkeh Research Station, Kurdestan Province, western Iran to investigate the effects of the change in land use on the degradation of Mol-lisols, their organic carbon content, clay mineralogy and K+ status. The study area was partly under cultivation (for over 40 years) and partly preserved as rangelands. The re-sults revealed that Mollisols are the dominant soils in non-cultivated natural rangelands. The adjacent cultivated soils, however, lack enough organic carbon to meet the require-ments of Mollisols. Cultivation practices had exerted adverse effects on some such major soil properties as organic carbon, cation exchange capacity, as well as macro- and micro-structure. Clay minerals and different forms of potassium did not show significant differ-ences in the two land uses. Parent material rich in such potassium bearing minerals as feldspars and mica, as well as the dominance of illite in soils, were probably the main fac-tors responsible for adjustment of the soil K+, rendering the changes relatively non-significant.

Volume 11, Issue 4 (12-2023)
Abstract

Aims: The current research was conducted with the purpose of analyzing the land use change in a 20-year period. In this regard, an integration of remote sensing and the DPSIR framework was done to investigation of the land use change in the Eskandari Watershed located in the Zayandeh roud Watershed.
Materials & Methods: Through conducting a workshop and stakeholder interactions, a set of drivers (D), pressures (P), state (S), impacts (I), and responses (R) were identified and investigated in the DPSIR framework. Satellite images of Landsat 5 and 8 (2011 and 2021) and the Markov model for predicting the land use changes (2031) were used to investigate the dynamics of land use change. Maps of land use the three times, the focus group discussions (FGDs), expert’s experiences and stakeholders were applied using an interview and questionnaire methods to identify the changes components based on the DPSIR framework.
Findings: The findings of the research showed that in 2011, 2021, and 2031, irrigation and dry farming were the best kind of land use in the Eskandari Watershed, covering 42.16%, 40.66%, and 52.19% of the total area, respectively. Also, moderate rangeland (28.57%), in the Eskandari Watershed showed a declining trend.
Conclusion: Due to the increasing process of land use destruction in the future and the ineffectiveness of solutions in the past years, to prevent the cross-sectional strategy of the isusues, is recommended to use the DPSIR comprehensive approach for problem solving and optimal management responses
S. Ayoubi, F. Khormali, K. L. Sahrawat, A. C. Rodrigues de Lima,
Volume 13, Issue 5 (9-2011)
Abstract

A study was conducted to determine suitable soil properties as soil quality indicators, using factor analysis in order to evaluate the effects of land use change on loessial hillslope soils of the Shastkola District in Golestan Province, northern Iran. To this end, forty surface soil (0-30 cm) samples were collected from four adjacent sites with the following land uses systems: (1) natural forest, (2) cultivated land, (3) land reforested with olive, and (4) land reforested with Cupressus. Fourteen soil chemical, physical, and biological properties were measured. Factor analysis (FA) revealed that mean weight diameter (MWD), water stable aggregates (WSA), soil organic matter (SOM), and total nitrogen (TN) were suitable for assessing the soil quality in the given ecosystem for monitoring the land use change effects. The results of analysis of variance (ANOVA) and mean comparison showed that there were significant (P< 0.01) differences among the four treatments with regard to SOM, MWD, and sand content. Clearing of the hardwood forest and tillage practices during 40 years led to a decrease in SOM by 71.5%. Cultivation of the deforested land decreased MWD by 52% and increased sand by 252%. The reforestation of degraded land with olive and Cupressus increased SOM by about 49% and 72%, respectively, compared to the cultivated control soil. Reforestation with olive increased MWD by 81% and reforestation with Cupressus increased MWD by 83.6%. The study showed that forest clearing followed by cultivation of the loessial hilly slopes resulted in the decline of the soil quality attributes, while reforestation improved them in the study area.
N. Rezaie, M. H. Roozitalab, H. Ramezanpour,
Volume 14, Issue 7 (12-2012)
Abstract

All of the tea plantations in Iran are concentrated in the Caspian Sea region on soils previously developed under deciduous natural forests. This research conducted to study the effect of land use change (from forest to tea) on selected physico-chemical and mineralogical properties of soils under humid climate and mountainous landscape in Northern Iran. Three transects facing west to northwest in both tea plantation and the nearby natural forest were selected. A total of 18 soil profiles formed on different physiographic positions i.e. summit, shoulder and foot slope were studied and morphological features of the soils were described. Soil samples taken from each horizon were analyzed. A two factor completely randomized design was used to take soil samples from surface horizons in each transect. Results showed that after changing forest to tea cultivation pH, cation exchange capacity, clay content and the amount of organic carbon of the soils were decreased at P< 0.01 significance level, but bulk density was increased compared to soils under natural forest. X-ray diffractograms of clay fractions showed that vermiculite, vermiculite–illite mixed layers and hydroxy interlayered clay minerals were the major clay components. Soils under tea cultivation possessed highly developed and more prominent argillic horizons and contained more clay fraction in the lower horizons in all physiographic positions.

Volume 24, Issue 1 (3-2020)
Abstract

Introduction
 Population growth and migration of (from or to) cities has led to the construction of unstructured and large changes in the spatial structure and expansion of cities. This causes changes in the surface of the earth and the conversion of natural effects of the earth such as soil and vegetation to the urban texture. So, the first consequence of the expansion of cities is land use change. Today, land use change and land cover have become a major challenge in many countries. Hence, the study of these changes plays a major role in the world's environmental studies. In order to better manage natural and human ecosystems and develop long-term planning, it is necessary to model land use changes and predict future changes.
Methodology
The research method is applied in terms of purpose and  the nature and method of descriptive-analytic research, and the method of data collection in this study is also a library research. In this study, for land use changes during the 29-year period, images were first provided  from the website of the Geological Survey of the United States. Then, using ENVI software, the pre-processing operation was performed to apply atmospheric and radiometric corrections. Also, the specimens of educational and supervised classification of images for land use in four levels (lands, rice field, forests, gardens and Water zone) were studied. Then, in the IDRISI SELVA software, simulation was used to predict future changes using the perceptron neural network.
Results and Discussion
Before the main analysis of the data and the extraction of the information, it is necessary to perform the pre-processing operation. Then several time satellite images used in the research after atmospheric and radiometric corrections were used to prepare the land use map and Maximum likelihood algorithm was used to classify the desired classes. The selection of effective variables in predicting urban growth is an important and useful information for the user to understand the desirability of land use change. Therefore, in the present study, distance variables from the road are considered as independent static variables, and distance from the landfill, distance from the land, and the distance from the forest and gardens are considered as independent variables were used. Among the models that are used in the simulation of land use change, neural networks are multilayered perceptron. Therefore, this model was used to simulate land use changes in this study. Finally, according to the Kramer coefficient, the distance from the road has the least effect and the distance variable of the land has the greatest impact on land use change and transmission potential modeling. Then, user-potential mapping maps were generated through multi-layer perceptron neural networks for an 8-year time span. Also, in the maps produced, regions with a warm color spectrum have the greatest potential for change, and are more vulnerable to areas with a cool color spectrum.
Conclusion
Today, land use change and land cover have become a major challenge in many countries. These changes have a direct impact on environmental components such as soil, water and atmosphere. Which This causes changes in the surface of the earth and the conversion of natural effects of the earth such as soil and vegetation to the urban texture. Due to the fact that the city of Lahijan, like many other cities in Iran, has faced expansion of construction in recent years, so, today, the city has undergone significant changes in land use. The purpose of this study is to model and predict land use changes using the Multilayer Perceptron, . In this regard, in order to implement this model, Landsat classified satellite images for the four periods of 1989, 2000, 2010 and 2018, as well as four independent variables including distance from the road, distance from Shalizar, distance from the forest and gardens, And and distance from the land, were built to simulate land use changes. The study resulted in the generation of transmission potential mapping with the 84.58 accuracy index, which shows that the distance from the land constructed  the greatest impact and the distance from the road has the least effect on land use change variations.

 


Volume 24, Issue 3 (10-2020)
Abstract

Extended abstract
Introduction
Land use is one of the most important biophysical and socio-economic characteristics in any watershed. The science of land change has recently been introduced as one of the fundamental components of global environmental change and sustainable development research. Monitoring land changes is important in future planning and natural resource management. Therefore, the need to detect such changes in an ecosystem is very important. Therefore, the need to detect such changes in an ecosystem is very important to take appropriate action if necessary. . Due to the fact that Lake Urmia is an important ecotourism center in Azerbaijan, with the drying up of the lake, Greater Azerbaijan and all the areas affected by this phenomenon will face a recession of domestic tourists. These factors, in turn, will lead to the migration of residents of the villages of this region to the surrounding cities and social problems in these cities. Its catchment area has been one of the water resources of this area[r11] . But the extent to which these changes, and especially the change in land use, have taken place, requires special study. In general, it is possible to study land use changes in both terrestrial and remote sensing methods. However, in recent decades, with the development of hardware and software facilities for processing satellite images, as well as the ease of access to multi-spectral and ultraviolet images, the use of remote sensing techniques to produce land use maps has become more common. The use of remote sensing technology has a special place in natural resource studies. Multi-time comparison, information updates, digital processing, data diversity, and data transfer speeds have made remote sensing the most important technology in detecting changes.
Methodology
The approach of the present study is developmental-applied and its descriptive-analytical method. According to the subject of the research and in line with the objectives defined in this research, satellite image with the specifications listed in Table (1) and the softwares of Google Earth, ENVI4.8, ArcGIS10.2 have been used. To use satellite imagery to perform techniques, all images must have the same coordinates. Remote sensing techniques, especially those used to classify land use and detect changes, are usually monitored and analyzed based on similar pixels in multi-time images; Corrections, images are not properly geometrically and radiometrically corrected, research accuracy is reduced. Thus, the satellite images of 1989, 2000, 2016, and 2019 were returned to the image with an RMS error of 0.42 pixels, capturing 20 control points from the image surface to the image method. In geometric correction, the ground control points were tried to have a good distribution at the image level so that the mathematical model used to calculate the unknown coefficients in the equation would have less error. To convert the corrected image coordinates to the non-corrected image, a second-order function was used. . In this study, the numerical value reduction method of dark pixels for radiometric correction of images has been used. In this method, a constant value of the total value of the pixels in a given band is reduced to apply radiometric corrections to each satellite image. In the next step, the images were mosaic due to the location of the study area in two women (1368-348)[r12] . Then, using field visits and the global location apparatus, instructional samples for each use (lake, agriculture, salt marsh, other lands) were identified in the study area.
Results and discussion
In this study, three supervised classification methods (neural network, backup vector machine and maximum probability) have been used to extract land use maps. By comparing the accuracy of the classification obtained from the methods mentioned in Table (2), it was found that the classification method of the backing vector machine with a cap rate of 99.75% is more accurate than other methods. According to the results of both classification methods of machine vector support and neural network, precise methods for extracting land uses and in separating the phenomena that have close spectral behavior are very successful, especially support vector machine  , which . Which was a bit successful.[r13] 
Conclusion
In this study, first, images of measuring satellites (MSS-TM-OLI) were used and the map of Urmia Lake, lake landscaping and its surroundings were was extracted by applying supervised classification (support vector machine, neural network and maximum probability). . Comparison of image stratification methods showed that the support vector machine method has more classification accuracy than the other two methods due to its general accuracy and higher capability coefficient. The results also show that satellite imagery has a significant ability to extract land uses. Also, in order to investigate the trend of land use change, maps extracted from satellite imagery in 1989, 2000, 2016 and 2019 were compared. Examination of land use maps in the three mentioned periods showed significant changes in land cover. These changes include: Agricultural land use area has increased significantly from 1989 to 2019 due to the favorable area for agriculture and drilling wells. Numerous and the use of aquifers has been underground . Analysis of Landsat satellite images showed that significant fluctuations in the lake's water level have occurred over the years. So so that the water level changes of Urmia Lake from 1989 to 2016 have increased from 5348 to about 2705 square kilometers. However, from 2016 to 2019, due to heavy cross-sectional rains, it had an increase in water area of ​​1644 square kilometers. The images also show that the coastline, especially in the east and southeast of the study area, has a significant number of boys. From 1989 to 2000, the area of ​​this land use increased by 378 square kilometers. Also, between 2000 and 2016, its area continued to rise and increased to 786 square kilometers. However, due to the increase in cross-sectional rainfall during 2016 to 2019, the water level of the lake has increased and some of the salt marshes have been submerged and the land use area of ​​the salt marshes has decreased by 838 square kilometers.



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