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جستجوی مقالات مرتبط با کلیدواژه « land use » در نشریات گروه « محیط زیست »

تکرار جستجوی کلیدواژه «land use» در نشریات گروه «علوم پایه»
  • فریبا هدایت زاده، علیرضا ایلدرمی*، نسرین حسن زاده، نادر بهرامی فر، مهدی بنایی
    سابقه و هدف

    کیفیت حوضه رودخانه با سلامت اکوسیستم آن مشخص می شود تا منابع و خدمات قابل توجه و ارزشمندی را برای استفاده انسان و خود حوضه فراهم کند. با این حال، تغییرات الگوی کاربری اراضی که انعکاسی موثر از فعالیت های انسانی است، سلامت رودخانه را به شدت مختل کرده و محرک اصلی کاهش کیفیت آب است. بررسی رابطه بین الگوی کاربری اراضی و کیفیت آب رودخانه، مبنای مهمی برای ایمنی کیفیت آب و مدیریت موثر کاربری اراضی فراهم می کند. لذا، هدف این مطالعه بررسی تاثیر الگوهای کاربری اراضی بر کیفیت آب های سطحی در محدوده زیرحوضه آبخیز رودخانه مارون است. 

    مواد و روش ها

    به منظور نمونه برداری از منطقه مطالعاتی ابتدا مرز زیرحوضه آبخیز رودخانه مارون تعیین و سپس زیرحوضه مورد نظر با استفاده از ابزار آنالیز هیدرولوژیکی در نرم افزار ArcGIS به زیرحوضه های مختلف کوچکتر تقسیم و نقشه آبراهه های منطقه تهیه شد. سپس ایستگاه های نمونه برداری از نقطه خروجی هر یک از این زیرحوضه ها در محدوده ی زیرحوضه اصلی انتخاب شدند. سپس به منظور اندازه گیری پارامترهای کیفی آب محدوده مورد مطالعه، نمونه برداری از 38 ایستگاه پایش در سطح زیرحوضه ها با سه تکرار در بهار 1402 انجام شد. نقشه کاربری اراضی نیز جهت ارزیابی تغییرات و تاثیر الگوهای کاربری و پوشش زمین بر وضعیت کیفیت آب زیرحوضه آبخیز رودخانه مارون با استفاده از تصاویر لندست تهیه شد. سپس با استفاده از سیستم اطلاعات جغرافیایی و تکنیک های آماری چند متغیره، اثرات کاربری اراضی در سطح زیرحوضه مارون بر کیفیت آب رودخانه برآورد گردید. به علاوه جهت ارزیابی درجه کیفیت آب رودخانه در زیرحوضه های مختلف، از شاخص کیفیت آب (WQI) جهت تجزیه و تحلیل داده های کیفیت آب استفاده شد.

    نتایج و بحث: 

    نتایج بررسی توزیع الگوهای کاربری اراضی نشان داد که کاربری مرتع کاربری غالب در سطح زیرحوضه رودخانه مارون است و پارامترهای کیفیت آب تغییرات قابل توجهی را در ایستگاه های تحت پوشش کاربری کشاورزی و جنگلی نشان دادند. نتایج تجزیه و تحلیل همبستگی و رگرسیون خطی پارامترهای کیفیت آب و الگوهای کاربری اراضی در زیرحوضه رودخانه مارون نشان داد که کاربری کشاورزی با پارامترهای pH و DO ارتباط منفی و با پارامترهای  و  و Ca2+ ارتباط مثبت، کاربری جنگل همبستگی مثبت با DO و منفی با ، و کاربری شهری نیز همبستگی منفی با DO نشان داد. مقادیر WQI در ایستگاه های مختلف پایش شده بین 80/73 و 73/288 برآورد شد که براساس این شاخص، سطح سلامت رودخانه در بالادست زیرحوضه بهتر از پایین دست بود. بطور کلی براساس طبقه بندی WQI، 5/62 % کیفیت آب زیرحوضه آبخیز رودخانه مارون در طبقه "ضعیف"، 25 % در طبقه "بسیار ضعیف" و 5/12 % در طبقه "خوب" قرار داشت.

    نتیجه گیری

    یافته های حاصل از پژوهش بیانگر این است که کاربری کشاورزی عامل کلیدی تاثیرگذار بر پارامترها و در نتیجه افت کیفیت آب در سطح زیرحوضه رودخانه مارون می باشد و محدود کردن تخلیه رواناب ناشی از فعالیت های کشاورزی برای بهبود کیفیت آب در منطقه مورد مطالعه حیاتی است. این مطالعه اهمیت تغییرات کاربری / پوشش اراضی در کیفیت آب را برای تصمیم گیری آگاهانه در مورد برنامه ریزی و مدیریت صحیح حوضه برجسته می کند.

    کلید واژگان: کاربری اراضی, پایش کیفیت آب, تکنیک های آماری چند متغیره, توزیع فضایی, زیرحوضه رودخانه مارون}
    Fariba Hedayatzadeh, Alireza Ildoromi *, Nasrin Hasanzadeh, Nader Bahramifar, Mahdi Banaee
    Introduction

    The health of the river basin is determined by the health of its ecosystem to provide important and valuable resources and services for human use and the basin itself. However, the changes in the land use pattern, which is an effective reflection of anthropic activities, have greatly disturbed the health of the river and are the main driver of water quality reduction. Examining the relationship between land use patterns and river water quality provides an important basis for water quality safety and effective land use management. Therefore, the aim of this study is to investigate the influence of land use patterns on surface water quality based on the water quality monitoring data and land use data from 38 sampling points in the sub-basin of the Maroon River.

    Material and Methods

    In order to sample from the study area, first, the boundary of the sub-basin of the maroon river was determined, and then the sub-basin was divided into different smaller sub-basins using the hydrological analysis tool in ArcGIS software, and the map of waterways in the region was also prepared. Then, sampling stations were selected from the exit point of each of these sub-basins in the main sub-basin area. In order to measure the water quality parameters of the studied area, sampling was done from 38 monitoring stations in the sub-basins in triplicates in the spring of 2023. The land use map was prepared using Landsat satellite images to evaluate the changes and the impact of land use patterns on the water quality status of the Maroon River sub-basin. Then, using geographic information system and multivariate statistical techniques, the effects of land use on river water quality in the Maroon sub-basin were estimated. In addition, in order to evaluate the quality of river water in different sub-basins, water quality data was analyzed using the water quality index (WQI).

    Results and Discussion

    The results of the evaluation of the distribution of land use patterns showed that the use of pasture is the dominant use in the sub-basin of the Maroon River and the water quality parameters exhibited significant changes in the stations covered by agricultural and forest use. The results of correlation analysis and linear regression of water quality parameters and land use patterns in the Maroon River sub-basin showed that agricultural land has a negative relationship with pH and DO parameters and a positive relationship with parameters ,  and Ca2+, forest land has a positive correlation with DO and a negative correlation with , and urban land also showed a negative correlation with DO. WQI values in different monitoring stations were estimated between 73.80 and 288.73 which showed that the health level of the river upstream of the sub-basin was better than downstream. In general, based on the WQI classification, 62.5% of the water quality of the Maroon River sub-basin was in the "poor" class, 25% in the "very poor" class, and 12.5% in the "good" class.

    Conclusion

    The findings of the research showed that agricultural land was the key factor affecting the water quality parameters and as a result the decrease in water quality in the sub-basin of the Maroon River, so limiting the discharge of runoff from agricultural activities is critical for improving water quality in the study area. This study highlights the importance of LULC changes in water quality for making informed decisions on proper watershed planning and management.

    Keywords: Land Use, Water Quality Monitoring, Multivariate Statistical Techniques, Spatial Distribution, Maroon River Sub-Basin}
  • فرشاد کیوان بهجو، فروغ مسرت، سجاد قنبری*، سمیرا ساسانی فر

    عملیات بهره برداری و سیستم چوبکشی زمینی سبب ایجاد کوبیدگی و تخریب خاک شده و منجر به ایجاد تغییراتی در خصوصیات فیزیکی و شیمیایی خاک می شود. از آنجایی که اطلاعات کافی در خصوص زمان لازم برای بازیابی خصوصیات خاک تخریب شده وجود ندارد، از این رو پژوهش حاضر به منظور بررسی تاثیر فعالیت های چوبکشی زمینی بر خصوصیات خاک در جنگل های اسالم گیلان انجام شده است. به منظور جمع آوری داده، سه مسیر چوبکشی 5، 10 و 15 ساله انتخاب شدند. در هر کدام از این مسیرها و همچنین در جنگل طبیعی مجاور آن ها (منطقه شاهد)، نمونه های خاک جمع آوری شدند. در مجموع تعداد 27 نمونه خاک (مسیرهای چوبکشی و منطقه شاهد) از عمق صفر تا 10 سانتی متری برداشت شدند. در نهایت برخی خصوصیات خاک شامل ماده آلی، اسیدیته، هدایت الکتریکی، بافت خاک (درصد رس، سیلت و شن)، جرم مخصوص ظاهری و حقیقی، مقاومت خاکدانه، درصد رطوبت اشباع، مقاومت فروروی خاک و درصد تخلخل انداز گیری شدند. به منظور تجزیه و تحلیل داده ها از آزمون تجزیه واریانس و آزمون مقایسه میانگین دانکن استفاده شد. نتایج نشان داد که اختلاف معنی داری بین خصوصیات اندازه گیری شده (به استثنای مقاومت فروروی خاک) در مسیرهای چوبکشی با منطقه شاهد وجود ندارد. نتایج بررسی مقاومت فروروی خاک نیز نشان داد که در رابطه با این شاخص، اختلاف معنی داری بین مسیرهای چوبکشی با منطقه شاهد وجود دارد. نتایج این تحقیق نشان داد که پس از گذشت 5 سال از عملیات چوبکشی، خاک مناطق مورد مطالعه توانسته است به حالت اولیه خود برگردد.

    کلید واژگان: بازیابی خاک, جنگل های اسالم, چوبکشی زمینی, عملیات بهره برداری}
    Farshad Keyvan Behjou, Forugh Masarat, Sajad Ghanbari *, Samira Sasanifar
    Introduction

    One of the most important principles in the exploitation of forest resources is to minimize the amount of damage to the soil and reproduction during exploitation operations. Estimating the amount of these damages can play a significant role in forest management. As a result of the traffic of exploitation machines, the forest soil undergoes destruction and changes. For example, the decrease in soil carbon deposition causes large changes in the concentration of atmospheric carbon dioxide and as a result, reduces the proper functioning of the ecosystem. Logging paths are paths that are created spontaneously as a result of going back and forth from a specific strip (for pulling wood by a tractor) on the forest surface. These routes are defined by the authorities before the start of exploitation operations for the movement of tractors and skidders, so that as a result, the whole area of the parcel, trees and saplings are not damaged, which sometimes obstructs the harvesting (such as stones and so on) in the way of logging, it is done and it is sufficient. The main purpose of these routes is the removal of wood from the forest. As a result of this activity, they lead to negative effects on the balanced system of the forest, including soil degradation and the production of runoff and sediment in the region. Although the use of ground logging system causes the most environmental problems, it is a common operation to remove wood from the cutting area, which causes compaction in the soil. Several studies have been conducted in different parts of the world to investigate the effects of logging on the physical and chemical properties of soil. The results of these studies have shown that ground logging causes soil compaction and increases the soil bulk density. The highest amount of these factors was also observed in the place of wheel tracks. Also, the results of the studies have shown that the intensity of soil compaction at a depth of 0 to 10 cm is higher than at other depths and the amount of organic matter in logging paths has been recovered after 7 years. In most of the studies conducted regarding the effects of logging, most of the physical properties of the soil have been taken into consideration, while other structural and chemical properties of the soil are equally affected by this activity and are transformed. In this regard, in the present study, all the chemical and physical indicators of the soil have been considered in order to investigate the impact of logging activities on them. Examining changes in soil properties alone is not capable of responding to management guidelines. Also, by examining and determining the changes of soil indicators in logging routes with different time history, it is possible to maintain the quality of the soil and help to renew it. Therefore, in this research, the effects of changes in time intervals on the variability of physical and chemical indicators of soil due to logging routes have been investigated.

    Methodology

    Series 1 Nav Asalem belongs to watershed No. 7 Nav within the forest area of Talesh city under the supervision of the General Directorate of Natural Resources and Watershed Management of Gilan province. The forest cover is suitable and in good condition in terms of regeneration. The developed soil texture is mostly heavy to slightly heavy and in the area of shallow soils it is medium to light. The soil types in the studied plots are forest brown soil and forest washed brown soil. Linear sampling method was used to collect information. Then, at intervals of 50 meters, a sample line of 7.5 meters length was laid down on the logging paths perpendicular to the path, considering the center of the logging path. Then, at the beginning, on the wheels, and also at the end of the transect, soil sampling was done. Also, soil sampling was done at a distance of 30 meters from the logging roads (control area). Finally, 27 soil samples were collected from the depth of 0 to 10 cm using cylinder. By using soil samples, soil texture characteristics, apparent specific gravity, true specific gravity, total porosity, acidity, electrical conductivity and organic carbon percentage were measured. Analysis of variance and Duncan's mean comparison test were used to analyze the data.

    Conclusion

    The results showed that there is no significant difference between the measured properties (with the exception of the soil subsidence resistance) in the logging roads and the control area. The results of the investigation of soil subsidence resistance also showed that there is a significant difference between logging routes and the control area in relation to this index. In general, the presence and movement of exploitation machines in the forest causes many changes in the physical and chemical properties of the forest soils, as a result of which other major changes occur in the forest environment. In the current research, by examining the effect of ground logging operation on the soil properties of the logging routes, it was concluded that most of the investigated properties (with the exception of the soil subsidence resistance characteristic) were recovered after 5 years. Although the research results showed that there is a difference between the average characteristics of the investigated area and the control area, but these differences were not statistically significant. Therefore, it can be said that the soil of the logging roads has been able to return to its original state approximately within a period of 5 years. It seems that changing the logging routes after a maximum of 5 years and creating new logging routes (provided no new damage is caused to the forest ecosystem) or creating a consecutive rest period for the existing logging routes can restore the soil indicators of the forest ecosystem should be accelerated.

    Keywords: Soil recovery, Asalem forests, land logging, exploitation operations}
  • پانته آ لطفی، مژگان احمدی ندوشن*
    مقدمه

    خشکسالی پدیده ای طبیعی است که تقریبا در اکثر مناطق جهان اتفاق می افتد و به علت ارتباط نزدیک با محصولات کشاورزی و منابع آب یکی از پارامترهای مهم در علوم محیطی به شمار می رود. اثرات این پدیده در مناطق خشک و نیمه خشک به علت بارندگی سالانه کمترشان، بیشتر است. در مقابل روش های سنتی، استفاده از تکنیک سنجش از دور و تصاویر ماهواره ای به عنوان یک ابزار مفید برای پایش خشکسالی کشاورزی مورد توجه قرار گرفته است. هدف این پژوهش بررسی تغییرات کاربری اراضی کشاورزی با استفاده از شاخص تفاضل نرمال شده گیاهی و تصاویر ماهواره ای است.

    مواد و روش ها

    در این مطالعه، از تصاویر ماهواره ی لندست به منظور بررسی روند تغییرات کاربری اراضی کشاورزی در حوزه ی آبریز زاینده رود طی سال های 1363-1402 استفاده شد. برای انجام این مطالعه ابتدا از شاخص تفاضل نرمال شده گیاهی هر سال بهره گرفته شد. از آن جا که الگوهای متنوعی از کشت با تفاوت های زمانی مختلفی در طول یک سال در منطقه مورد مطالعه حضور پیدا می کند نمی توان از یک تصویر منتخب به عنوان مبنای یک سال استفاده کرد بر خلاف آن لازم است تا تصاویر مختلف برای زمان های مختلف سال مورد بررسی قرار گیرند تا مجموعه تمامی پیکسل هایی که در یک سال زراعی به زیر سطح کشت رفته اند، شناسایی و مشخص شوند. از آنجا که انجام این فرایند بسیار زمان بر خواهد بود، از یک رویکرد ابتکاری استفاده شد. ابتدا در سامانه گوگل ارث انجین تمام تصاویر سالانه لندست به صورت سال به سال فراخوانی شدند. سپس تصاویری که دارای پوشش ابر بودند حذف شده و فیلتر حداکثر بر روی باندهای تصاویر باقیمانده اعمال شد. سپس شاخص تفاضل نرمال شده گیاهی تصاویر سالانه جدید ساخته شد و با اعمال حدود آستانه 2/0، اراضی کشاورزی از سایر اراضی تفکیک گردید. وسعت اراضی کشاورزی در هر سال محاسبه و مدل رگرسیون خطی برای شناسایی روند تغییرات مورد استفاده قرار گرفت. به این عبارت که وسعت اراضی کشاورزی به عنوان متغیر وابسته و زمان در مقیاس سالانه به عنوان پارامتر مستقل مورد استفاده قرار گرفت.

    نتایج

    وسعت اراضی کشاورزی در اوایل دهه 1360، در حدود 25 هزار هکتار بوده است که با روندی کاهشی در طول زمان در سال های 1373 و 1393 به مقدار 21700 و 15180 هکتار رسیده و در نهایت در سال 1401 به کمترین مقدار خود برابر با 11250 هکتار رسیده است. این روند، کاهش 55 درصد در رهاسازی اراضی کشاورزی در این مقطع زمانی را نشان می دهد. همچنین مقدار شاخص تفاضل نرمال شده گیاهی در اراضی کشاورزی نیز به مرور زمان روند کاهشی را تجربه کرده است که بیانگر تغییر الگوی کشت به سمت کشت های کم تراکم با زیست توده کم مانند گندم است.

    بحث:

     نتایج حاصل از روند تغییرات وسعت کاربری کشاورزی در منطقه مورد مطالعه، الگوی کاهشی را نشان داد یعنی از دست روی اراضی کشاورزی رخ داده است که این روند منطبق با الگوی کاهش سطح آب سد زاینده رود است. این پدیده را می توان مستقیما به کاهش منابع آب در منطقه نسبت داد. در دهه اخیر، حجم آب اختصاص یافته برای انجام فعالیت های کشاورزی در این منطقه به دلیل نزدیک شدن حجم آب سد زاینده رود به محدوده های بحرانی بسیار کاهش پیدا کرده است.

    کلید واژگان: تصاویر ماهواره ای, شاخص تفاضل نرمال شده گیاهی, کاربری اراضی, زاینده رود}
    Pantea Lotfi, Mozhgan Ahmadi Nadoushan *
    Introduction

    Drought is a natural phenomenon that occurs almost in most regions of the world, and due to its relationship with agricultural products and water resources, it is considered as one of the most important issues in environmental sciences. The effects of this phenomenon are greater in arid and semi-arid regions due to their less annual rainfall. In contrast to traditional methods, the use of remote sensing techniques and satellite images has been considered as a useful tool for agricultural drought monitoring. The main objective of this study is to investigate changes in agricultural land use using normalized vegetation difference index and satellite images.

    Materials and Methods

    In this study, Landsat satellite images were used to investigate the trend of agricultural land use changes in the Zayandeh Rood catchment during 1984-2023. To do this study, the normalized plant difference index was used for each year. Since various patterns of cultivation with different time differences are present in the study area during a year, it is not possible to use a selected image as the basis of a year, on the contrary, it is necessary to examine different images for different times of the year. To identify and specify the set of all the pixels that have gone under the cultivation surface in one crop year. Since this process would be very time-consuming, an innovative approach was used. First, in the Google Earth Engine system, all the annual Landsat images were called year by year. Then, the images with cloud cover were removed and the maximum filter was applied to the bands of the remaining images. Then, the normalized vegetation difference index of new annual images was created and by applying a threshold of 0.2, agricultural lands were separated from other lands. The extent of agricultural land was calculated in each year and the linear regression model was used to identify the change process. In other words, the extent of agricultural land was used as a dependent variable and time was used as an independent parameter on an annual scale.

    Results

    The extent of agricultural land in 1984 was about 25 thousand hectares, which with a decreasing trend over time reached 21700 and 15180 hectares in 1994 and 2014, and finally reached its lowest value in 1401. It has reached 11.250 hectares. This trend shows a 55% reduction in the abandonment of agricultural land at this point in time. Also, the value of the normalized plant difference index in agricultural lands has experienced a decreasing trend over time, which indicates the change in the cultivation pattern towards low-density crops with low biomass such as wheat.

    Discussion

    The results of the changes in the extent of agricultural use in the study area showed a decreasing pattern, so, there has been a loss of agricultural land, which is consistent with the decreasing pattern of the water level of the Zayandeh Rood watershed. This phenomenon can be directly attributed to the reduction of water resources in the region. In the last decade, the amount of water allocated to carry out agricultural activities in this region has decreased a lot due to the water volume of the Zayandeh Rood watershed approaching critical limits.

    Keywords: Satellite Images, Normalized Vegetation Difference Index, Land Use, Zayandeh Rood}
  • گل آفرین زارع، بهرام ملک محمدی *، حمیدرضا جعفری، احمدرضا یاوری، احمد نوحه گر
    زمینه و هدف

    تالاب ها به عنوان یکی از مهم ترین انواع اکوسیستم های جهان به شدت در حال تهدید می باشند. تالاب پریشان علاوه بر اینکه جزء مناطق حفاظت شده ایران قرار دارد بلکه به عنوان تالاب بین المللی و نیز ذخیره گاه زیست کره نیز شناخته شده است. درک روند تغییرات این تالاب می تواند برای بهبود وضعیت آتی آن بسیار مفید باشد. از این رو هدف پژوهش حاضر پایش تغییرات پهنه آبی تالاب پریشان در بازه زمانی 30 ساله می باشد.

    روش بررسی

    در راستای هدف تحقیق تصاویر ماهواره لندست برای چهار دوره زمانی 1366، 1377، 1386 و 1395 به همراه سایر داده های مورد نیاز تهیه گردید. با انجام پردازش های مورد نیاز در نرم افزار ENVI 4.7، نقشه های پوشش اراضی تالاب پریشان با بهره گیری از شاخص تفاضلی نرمال شده پوشش گیاهی و شاخص تفاضلی نرمال شده آب در قالب روش درخت تصمیم در سه طبقه پهنه آبی، پوشش گیاهی و سایر اراضی استخراج شد.

    یافته ها

    نتایج نشان داد که در بازه بلندمدت سی ساله (1987 تا 2016) از مساحت 1963 هکتاری پهنه آبی تالاب پریشان تنها 13 هکتار در انتهای بازه باقیمانده است. پایش تغییرات نشان می دهد که پهنه آبی تالاب پریشان نسبت به سال 1366 حدود 1950، نسب به سال 1377 حدود 3605 و نسب به سال 1386 حدود 2272 هکتار کاهش مساحت داشته است.

    بحث و نتیجه گیری

    استفاده از داده های ماهواره ای و تکنیک های سنجش از راه دور به همراه مدل طبقه بندی درخت تصمیم حاکی از قابلیت روش مورد استفاده برای شناسایی و طبقه بندی پوشش اراضی در محدوده های تالابی که پوشش گیاهی و آب درهم تنیده اند، می باشد.

    کلید واژگان: تصاویر ماهواره ای, پوشش اراضی, روش درخت تصمیم, تالاب پریشان.}
    Golafarin Zare, Bahram Malek Mohammadi *, Hamidreza Jafari, Ahmad Reza Yavari, Ahmad Nohegar
    Background and Objective

    Wetlands, as one of the most important types of ecosystems in the world, are extremely threatened. In addition to being part of Iran's protected areas, the Parishan wetland is also known as an international wetland and biosphere reserve. Understanding the process of changing in this wetland, can be very helpful in improving its future status. Therefore, the purpose of the present study is to monitor the changes in the over a 30-year period.

    Material and Methodology

    For the purpose of the research, Landsat satellite images were prepared for four time periods of 1987, 1998, 2007 and 2016 along with other required data. By performing the required preprocessing in ENVI 4.7 software, Parishan wetland land-cover maps was extracted using Normalized Difference Vegetation Index and Normalized Difference Water Index combining with Decision Tree method in three class including water-body, vegetation and others land-cover.

    Findings

    The results showed that after 30 years only 13 hectares of 1963 hectares of Parishan wetland water-body remained. Monitoring of changes shows that Parishan wetland water-body has decreased by 1950 hectare in comparison to 1987, 3605 hectare in comparison to 1998 and 2272 hectare in comparison to 2007.

    Discussion and Conclusion

    using satellite data and remote sensing techniques along with Decision Tree classification model indicate the capability of this method for identifying and classifying land-cover in wetland areas where vegetation and water are intertwined.

    Keywords: Satellite Imagery, Land-Cover, Decision Tree Method, Parishan Wetland}
  • کبریا جعفری، مرضیه علی خواه اصل *، یحیی کوچ
    زمینه و هدف

    افزایش غلظت گازهای گلخانه ای در سال های اخیر منجر به افزایش گرمای جهانی و تغییرات اقلیمی شده است. ساده ترین راهکار برای کاهش سطح این گاز فرآیند ترسیب کربن است. طی این فرآیند، کربن در بخش های مختلف اکوسیستم ها ذخیره می شود که مهم ترین این بخش ها، خاک است. هدف از این پژوهش ارزیابی میزان ترسیب کربن خاک در کاربری های زراعت گندم، باغ مرکبات و مرتع در حوزه شهری بهشهر می باشد.

    روش بررسی

    در این تحقیق، نمونه برداری خاک در ده نقطه در هر یک از کاربری ها تا عمق 30سانتی متری با استفاده از روش تصادفی سیستماتیک انجام شد. بافت خاک، وزن مخصوص ظاهری، اسیدیته، رطوبت، کربن آلی، نیتروژن در محیط آزمایشگاه اندازه گیری شد. برای بررسی تفاوت یا عدم تفاوت میزان ترسیب کربن و مشخصه های مختلف خاک در کاربری های مختلف، از آزمون تجزیه واریانس و برای بررسی ارتباط بین میزان ترسیب کربن با مشخصه های مختلف خاک از همبستگی پیرسون استفاده شد.

    یافته ها

    نتایج نشان داد، به طور متوسط میزان ترسیب کربن در کاربری باغ مرکبات 54/0 تن در هکتار، زراعت گندم 36/0 تن در هکتار و مرتع 51/0 تن در هکتار می باشد. در نتیجه بین کاربری های مورد بررسی، کاربری باغی در اولویت اول و کاربری های مرتع و زراعت گندم در اولویت های بعد قرار گرفتند. همبستگی پیرسون نیز نشان داد از بین پارامترهای مورد بررسی، مشخصه نیتروژن بر تغییر پذیری میزان ترسیب کربن خاک موثرتر بوده است.

    بحث و نتیجه گیری

    بر اساس نتایج این پژوهش، کاربری های مختلف اثر متفاوتی بر میزان انباشتگی ترسیب کربن خاک دارد که در جهت مدیریت اراضی واقع در شمال کشور می بایست مورد توجه قرار گیرد.

    کلید واژگان: کاربری اراضی, مرتع, باغی مرکبات, زراعت گندم.}
    Kebriya Jafari, Marzieh Alikhah-Asl *, Yahya Kooch
    Background and Objective

    In recent years, increasing of greenhouse gases results in global warming and climate changes. Carbon sequestration is a result of carbon capturing in different parts of ecosystems, particularly in soil. The purpose of the present study is evaluation of carbon sequestration potential in wheat field, citrus garden and grassland in urban district of Behshahr.

    Material and Methodology

    The soil samples were collected from ten different points for each land use. They were randomly taken from a depth of 30 cm using systematic random sampling. Texture, apparent specific density, acidity, humidity, organic carbon and nitrogen of the soil were measured in laboratoty. The analysis of variance of soil properties indicates significant difference in studied land uses regarding to carbon sequestration.

    Findings

    The results showed that the average carbon sequestration in wheat field, citrus garden and grassland were 36% (Ton/Ha), 54% (Ton/Ha), 51%(Ton/Ha) , respectively. Totally, citrus garden had the highest carbon sequestration among studied land uses. Grassland and wheat field were ranked in second and third places, respectively. Via Pearson product-moment correlation, it was revealed that among all analyzed parameters, nitrogen had the most effect on soil carbon sequestration.

    Discussion and Conclusion

    The results of the present study show how land use effects on soil carbon sequestration, hence considering these results is necessary for Lands Management in North of Iran.

    Keywords: Land Use, Citrus Garden, Grassland, Wheat Field}
  • Jafar Mohammadi, Ebrahim Fataei *, Akram Ojaghi Aghchekandi, Lobat Taghavi

    Increasing population growth and civilization have caused great impacts on water quality. Among these, changes and excessive exploitation of land use have led to changes in the surface water quality to provide human needs. Therefore, the present study investigated the effects of land use on water quality using a spatial-statistical approach. To this end, the water quality data of 22 water quality-sampling stations were applied in the Qarasu watershed in Ardabil. Then, spatial analysis was conducted, including land use classification maps, watershed mapping and overlaying maps using GIS. Finally, correlation and multiple linear regression analysis were used to determine the relationship between water quality and land use variables. Pearson’s correlation coefficient showed proper percentages of vegetation cover, agricultural lands, woodlands, residential users, barren land and forest as well as weak pastureland have significant correlation with water quality variables. Multiple linear regression analysis with stepwise approach also indicated that of dependent parameters as water quality variables, the parameters of pH, Cl, Ca, Mg, Na and SAR are associated with land use as independent parameters including irrigated agriculture, first-grade pasture, third-grade pasture, woodlands, moorland, forest and residential users. Furthermore, validation of the model based on two models of the survey of predicted and actual values as well as root-mean-square error (RMSE) demonstrated good accuracy of the resulting model.

    Keywords: Water resources management, Land use, Water quality, Correlation}
  • بهار اکرمی مقدم، رسول ایلخانی پور زینالی، سامان نیک مهر*
    تهیه نقشه های پهنه بندی سیل از اقدامات اولیه و ضروری در مدیریت مناطق سیل گیر است. در این پژوهش به منظور بررسی و پهنه بندی نقشه پتانسیل سیل گیری در استان کردستان از روش تحلیل سلسله مراتبی و سیستم اطلاعات جغرافیایی استفاده شد. از متغیرهای موثر بر سیل گیری شامل بارش، شیب، فاصله از رودخانه، تراکم زهکشی ، کاربری اراضی و شاخص رطوبت توپوگرافی به منظور پهنه بندی و تهیه نقشه سیل گیری استفاده شد. معیارهای موثر بر پتانسیل سیل گیری به جز کاربری اراضی و بارش به وسیله مدل رقومی ارتفاع تهیه و هریک از معیارهای مذکور به وسیله نرم افزار Expert Choice وزن دهی شدند. نتایج نشان داد که معیارهای بارش، شیب و فاصله از رودخانه به ترتیب با وزن های 409/0، 295/0و134/0 از بیش ترین اهمیت در پتانسیل سیل گیری برخوردار بوده اند. نواحی مختلف استان از نظر پتانسیل سیل گیری در پنج رده خیلی کم (1/0 %)، کم (9/1%)، متوسط (%43)، زیاد (%52) و خیلی زیاد (%3) قرار گرفتند. پتانسیل سیل گیری در خروجی حوزه های آبخیز، محدود به نواحی پایین دست و کم شیب رودخانه های پرآب بخش غربی و مرکزی استان، خیلی زیاد بود.
    کلید واژگان: بارش, رودخانه, زهکشی, شیب, کاربری اراضی}
    Bahar Akrami Moghadam, Rasool Ilkhanipour Zeynali, Saman Nikmehr *
    Preparation of flood zoning maps is one of the primary and necessary measures in the management of flood prone areas. In this study, analytic hierarchy process, and geographic information system were used to assess and zoning the flood potential map in Kurdistan province, Iran. The factors involved in flooding including rainfall, slope, distance from river, drainage density, land use and topographic wetness index were used for zoning and providing flood maps. Effective criteria, except for land use and rainfall, were prepared using the digital elevation model, and each factor was weighted by Expert Choice software. The results showed that rainfall, slope, and distance from the river with weights of 0.409, 0.295, and 0.134 were the most important factors, respectively. In terms of flood potential zoning, different areas of the province were placed in five categories: very low (0.1%), low (1.9%), medium (43%), high (52%) and very high (3%). The flood potential at the outlet of the watersheds limited to the downstream and low-slope areas of main rivers in the western and central parts of the province was very high.
    Keywords: Rainfall, River, Drainage, Slope, land use}
  • مریم دهمرده پهلوان، محسن شهریاری مقدم*، سعیده ملکی نجف آبادی، وحید راهداری
    مقدمه

    مناطق ساحلی در سراسر جهان از اهمیت اجتماعی و اقتصادی زیادی برخوردار می باشند. این مناطق علاوه بر ارایه خدمات مهم اکوسیستمی، قابلیت شایانی برای فعالیت هایی از قبیل گردشگری، صنعتی و ترابری داشته و به توسعه اقتصادی و اجتماعی کشورها کمک زیادی کرده است. از سویی دیگر با توجه به اینکه مناطق ساحلی از پیچیده ترین اکوسیستم ها هستند، نیازمند پایش و برنامه ریزی برای حفاظت هرچه بیشتر می باشند، بنابراین تشخیص به موقع و دقیق تغییرات کاربری اراضی که پایه و اساس درک بهتر تعاملات میان انسان و پدیده های طبیعی است، مقدمات لازم را برای مدیریت و استفاده کارآمد از قابلیت های مناطق ساحلی را فراهم می کند.

    مواد و روش ها

    پژوهش حاضر با هدف بررسی تغییرات کاربری و پوشش اراضی در نواحی ساحلی چابهار برای 4 دوره شامل سال های 1368، 1378، 1388 و 1398 با استفاده از از سری زمانی داده های ماهواره لندست انجام گرفت. به منظور تهیه نقشه پوشش زمین، عملیات پردازش بر روی تصاویر طی مراحل پیش پردازش و پردازش انجام و طبقه بندی به روش ترکیبی انجام شد. دقت نقشه های تهیه شده با تهیه ماتریس خطا، محاسبه شاخص کاپا و صحت کلی به ترتیب بیش از 8/0 و 80 درصد، محاسبه گردید. سپس با استفاده سنجه های سیمای سرزمین تحلیل تغییرات الگوی مکانی طبقات کاربری اراضی انجام گرفت.

    نتایج

      نتایح نشان داد در سال های مورد مطالعه بیش ترین درصد کاربری مربوط به اراضی بایر بوده است. پوشش اراضی شوره زار و بایر در سال 1398 نسبت به سال 1368 به ترتیب 28/398 و 7/75 هکتار کاهش در حالی که پوشش اراضی پهنه آبی در سال 1398 نسبت به سال 1368 به میزان 3/115 هکتار افزایش را نشان داد. بررسی کاربری پوشش گیاهی نیز نشان داد این کاربری در تمامی دوره ها کمترین میزان مساحت را به همراه کاربری انسان ساخت به خود اختصاص داده است و افزایش تدریجی داشته اند. هم چنین ارزیابی صحت طبقه بندی نقشه پوشش اراضی نشان دهنده صحت بالای نقشه تولیدی هستند به طوری که در دوره 1368 با 25/93 بیشترین و دوره 1398 با 6/85 کمترین میزان صحت جهت طبقه بندی به دست آمده است. نتایج نشان داد در سال 1398 تعداد لکه پهنه آبی، پوشش گیاهی و انسان ساخت (830، 2662 و 4 به ترتیب) نسبت به سال 1368 (146، 2386 و 1 به ترتیب) افزایش یافته در حالی که تعداد لکه شوره زار و اراضی بایر در سال 1398 (643 و 761 به ترتیب) نسبت به سال 1368 (720 و 1060 به ترتیب) کاهش نشان داد.

    بحث: 

    نتایج مطالعه حاضر نشان داد تغییرات قابل ملاحظه ایی در خط ساحلی چابهار طی 30 سال اخیر رخ داده است. نتایج حاکی از آن است که در منطقه مطالعاتی از سال 1368 تا 1398 پوشش گیاهی رشد قابل ملاحظه ایی کرده است (از 34/116 به 30/202) و در مجموع 96/85 به کاربری پوشش گیاهی افزوده شده است. افزایش کاربری پوشش گیاهی را می توان به افزایش کشاورزی نسبت داد. نتایج آشکارسازی تغییرات مناطق انسان ساخت نیز رشد چشمگیری را (18/133، 74/205، 29/228 و 42/411 به ترتیب در سال های 1368، 1378، 1388 و 1398) در دوره  مورد مطالعه نشان داده است. به طور کلی می توان گفت با توجه به تجزیه و تحلیل های سنجه های سیمای سرزمین در  دوره مطالعه افزایش کاربری های انسان ساخت و تغییرات محیط زیستی ادامه داشته است و طرح های مدیریت یکپارچه مناطق ساحلی اتخاذ نشده است.

    کلید واژگان: کاربری و پوشش اراضی, سنجش از دور, سیمای سرزمین, سواحل چابهار}
    Maryam Dahmardeh Pahlavan, Mohsen Shahriari Moghadam *, Saeedeh Maleki Najafabadi, Vahid Rahdari
    Introduction

    Coastal areas worldwide hold significant social and economic importance. These areas, in addition to providing essential ecosystem services, have considerable potential for activities such as tourism, industry, and transportation, contributing significantly to the economic and social development of countries. Given that coastal areas are among the most complex ecosystems, they require monitoring and planning for enhanced protection. Timely and accurate identification of land use changes, which form the basis for better understanding human-nature interactions, provides the necessary groundwork for the efficient management and utilization of coastal resources.

    Materials and Methods

    The present study aims to investigate land use and land cover changes in the Chabahar coastal areas for four periods, including the years 1368, 1378, 1388, and 1398, using Landsat satellite time series data. Land cover mapping was performed through preprocessing and processing stages, followed by classification using a combined method. The accuracy of the produced maps was assessed using error matrix, Kappa index, and overall accuracy, which were greater than 80% and 0.8, respectively. Land use changes were analyzed using landscape metrics.

    Results

    The results indicated that barren land had the highest land use percentage in all studied years. Saline and barren land cover decreased by 398.28 and 75.7 hectares, respectively, from 1368 to 1398, while aquatic land cover increased by 115.3 hectares in 1398 compared to 1368. The analysis of vegetation cover also revealed that this land use, along with human-made structures, consistently allocated the smallest area in all periods, gradually increasing. The accuracy assessment of land cover classification showed high accuracy in the produced maps, with the highest and lowest accuracy rates in 1368 (93.25%) and 1398 (85.6%), respectively. In 1398, the number of patches for aquatic land, vegetation cover, and human-made structures increased (830, 2662, and 4, respectively) compared to 1368 (146, 2386, and 1, respectively), while the number of saline and barren land patches decreased in 1398 (643 and 761, respectively) compared to 1368 (720 and 1060, respectively).

    Discussion

    The study results demonstrated considerable changes in the Chabahar coastline over the past 30 years. The findings indicated a significant increase in vegetation cover from 1368 to 1398 (from 116.34 to 202.30 hectares), contributing a total of 85.96 hectares to land use. This increase in vegetation cover can be attributed to agricultural expansion. The detection results of changes in human-made areas also showed substantial growth (133.18, 205.74, 228.29, and 411.42 in 1368, 1378, 1388, and 1398, respectively) during the study period. Overall, it can be concluded that, based on the analysis of landscape metrics, the increase in human-made land uses and environmental changes has continued, and integrated management plans for coastal areas have not been adopted.

    Keywords: Land use, land cover, Remote Sensing, Landscape metrics, Chabahar coasts}
  • اردوان زرندیان*، فاطمه محمدیاری، رویا موسی زاده، مجید رمضانی مهریان، جلیل بادام فیروز
    مقدمه

    منابع خاک نقش مهمی در تامین کالاهای مادی ضروری برای انسان و سایر موجودات دارد و خدمات اکوسیستمی متنوعی را به انسان ارایه می دهد. همچنین خاک برای مدت طولانی به عنوان یک زیرساخت سبز مهم برای حفظ کشاورزی و جنگلداری به عنوان پایه رشد گیاهان عمل کرده است. علاوه بر این، خاک می تواند خدمات مختلف اکوسیستمی مانند بی حرکت کردن آلاینده ها، کنترل آب باران، ترسیب کربن و تامین زیستگاه را ارایه دهد که به صورت مستقیم برای انسان سودمند است. خدمات ارایه شده توسط اکوسیستم ها به انسان را خدمات اکوسیستمی می گویند. نگهداشت خاک به پتانسیل اکوسیستم ها در کنترل فرسایش خاک و حفظ خاک می گویند که در طبقه خدمات تنظیمی قرار دارد.

    مواد و روش ها

    کمی سازی نگهداشت و فرسایش خاک در نرم افزار InVEST با مدلInVEST Sediment Delivery Ratio  (SDR) ارزیابی شد. ورودی های مورد نیاز برای اجرای این مدل شامل: نقشه کاربری اراضی، فاکتور K (فرسایش پذیری خاک)، فاکتور R (فرسایندگی باران)، فاکتور C (نوع کاربری اراضی و پوشش)، فاکتور P (اقدامات حفاظتی)، DEM (مدل رقومی ارتفاع) و جدول بیوفیزیکی است.

    نتایج

    بر اساس نتایج، پتانسیل اتلاف خاک و انتقال رسوب در محدوده مطالعاتی به ترتیب از صفر تا 18/248 تن در پیکسل و صفر تا 25/57 تن در پیکسل متغیر است. نگهداشت خاک نیز در طیفی از صفر تا 85/124 تن در پیکسل در محدوده مورد مطالعه برآورد شده است. نتایج نشان داد که بیشترین مقدار اتلاف خاک در زیرحوضه 14 با 13716400 تن در سال و کمترین میزان اتلاف خاک در زیرحوضه 4 با 416594 تن در سال رخ می دهد. همچنین بیشترین مقدار خدمت اکوسیستمی نگهداشت خاک در زیرحوضه 13 با 4304414 تن در سال و کمترین مقدار آن در زیرحوضه 4 با 5645 تن در هکتار در سال تدارک می شود.

    بحث: 

    جنگل های متراکم استان سمنان در منتهی الیه شمالی استان، با بیش از 36 تن در هکتار بیشترین خدمت اکوسیستمی نگهداشت خاک و محدوده های کویری، دریاچه نمک و شوره زار کمترین میزان خدمت نگهداشت خاک را فراهم می نمایند. بر همین اساس، مجموعه جنگل های استان شامل جنگل های متراکم، نیمه متراکم، کم تراکم و تنک در مجموع 4269166 تن در سال موجب نگهداشت خاک در استان می شوند. همچنین مراتع خوب، سالانه موجب نگهداشت بیش از 18 تن در هکتار از خاک استان می شوند و مجموع کارکرد نگهداشت خاک توسط انواع مراتع استان شامل مراتع خوب، متوسط و فقیر به میزان 9395160 تن در سال است که با توجه به  مساحت حدود 18 برابری مراتع نسبت به جنگل ها، می توان گفت بیشترین خدمت اکوسیستمی نگهداشت خاک به لحاظ توزیع جغرافیایی این خدمت در استان توسط مراتع تدارک می شود؛ هرچند که محدوده های جنگلی دارای توان بیشتری برای حفاظت از خاک هستند. کاربری های باغ و مزارع دیم بعد از  پوشش های طبیعی جنگلی و مرتعی، به ترتیب با تدارک نگهداشت خاک به میزان 86/7 و 15/2 تن در هکتار در رتبه های بعدی قراردادند. اما سایر کاربری های انسان ساخت مانند محدوده های شهری چون معمولا با حذف یا کاهش پوشش گیاهی همراه هستند، موجب زایل شدن این خدمت اکوسیستمی می شوند. با توجه به استقرار نواحی شهری در نیمه شمالی محدوده مورد مطالعه و اثر منفی آنها بر این خدمت اکوسیستمی، اهمیت حفاظت از پوشش های جنگلی و مرتعی استان برای حفظ استمرار تدارک خدمت نگهداشت خاک یک امر حیاتی محسوب می شود.

    کلید واژگان: خدمات اکوسیستم, نگهداشت خاک, کاربری اراضی, سمنان}
    Ardavan Zarandian *, Fatemeh Mohammadyari, Roya Mousazadeh, Majid Ramezani Mehrian, Jalil Badamfirooz
    Introduction

    Soil resources play an important role in providing the necessary material goods for humans and other organisms and also deliver multiple ecosystem services that are essential for life on earth. They have also served for a long time as an important green infrastructure in protecting agricultural and forest landscapes by providing plants a foothold for their roots and holding the necessary nutrients for their growth. In addition, soils can provide various ecosystem services such as contaminant immobilization, rainwater control, carbon sequestration, and habitat provision that are directly beneficial for humans. Services provided by ecosystems for humans are called ecosystem services. Soil retention, which refers to the potential of ecosystems for controlling soil erosion and conserving soil, is classified in the class of regulating services.    

    Materials and Methods

    The InVEST Sediment Delivery Ratio (SDR) model was used in InVEST Software to quantify soil retention and erosion. The required inputs for implementing this model include land use maps, K-factor (soil erodibility), R-factor (rain erosivity), C-factor (land use and land cover or LU/LC), P-factor (support practices), DEM (digital elevation model), and the biophysical table. 

    Results

    Based on the results, the potential of soil loss and sediment transport in the study area ranged from zero to 248.18 t/pixel and from zero to 57.25 tons per pixel, respectively. Soil retention is also estimated in a range from zero to 124.85 tons per pixel in the studied area. The largest amount of soil loss happened in sub-basin number 14 with 13716400 t/year and the smallest in sub-basin number 4 with 416594 t/year. Most of the ecosystem service of soil retention belonged to sub-basin number 13 with 4304414 t/ha/ year and the least to sub-basin number 4 with 5645 tons/ha/year.

    Discussion

    The dense forests in the northernmost part of Semnan Province provide the most part of the ecosystem service of soil retention with more than 36 t/ha and the desert areas, the salt lake, and the salt marsh the least. Based on this, the province's forests, including dense, semi-dense, sparse and thin forests, contribute to the maintenance of soil in the province by a total of 4269166 tons per year. Also, good pastures maintain more than 18 tons per hectare of the province's soil every year, and the total function of soil maintenance by all types of pastures in the province, including good, medium and poor pastures, is 9395160 tons per year. Since the area covered by the pastures is 18 times more than that by the forests, we can say that most of the ecosystem service of soil retention is provided by the pastures due to the geographical distribution of this service in the province, despite the fact that forests are more capable in soil conservation than pastures. The orchards and rainfed agricultural land rank third and fourth, respectively, in soil retention with 7.86 and 2.15 tons of soil/ha, respectively. However, man-made land uses such as urban areas decrease this ecosystem service because they are usually accompanied by removing or reducing the vegetation. The urban areas are located in the northern part of the study area, and they have negative impacts on this ecosystem service. Therefore, protection of the forest and rangeland covers in the province is vitally important for the continued conservation of the ecosystem service of soil retention.

    Keywords: Ecosystem services, Soil Retention, land use, Semnan}
  • رئوف مصطفی زاده*، امیرحسین قربانی، محسن ذبیحی

    تعیین ضریب رواناب به صورت توزیعی می تواند در شناسایی مناطق همگن و مولد رواناب مورد استفاده واقع گردد و با این روش، موقعیت واحدهای همگن و مشابه از نظر رفتار هیدرولوژیک در آبخیز مشخص و ترسیم می گردد. هدف تحقیق حاضر، تهیه نقشه توان سیل خیزی و تولید رواناب سطحی با دو روش جدول ترکیبی و روش سرویس حفاظت خاک (SCS) در حوضه محمدآباد کتول در استان گلستان است. بر این اساس اطلاعات لازم برای تعیین ضریب رواناب شامل نقشه کاربری اراضی، شیب و بافت خاک تهیه شد و سپس مقادیر ضریب رواناب با استفاده از جدول سه ترکیبی در آبخیز مطالعاتی تعیین شد. هم چنین با رقومی نمودن لایه های مورد نیاز، نقشه شماره منحنی منطقه مورد مطالعه استخراج شد و بر اساس اطلاعات بارش حداکثر 24 ساعته، با استفاده از رابطه SCS، ارتفاع رواناب و مقدار ضریب رواناب مشخص شد. در ادامه نتایج روش جدول ترکیبی و روش SCS در برآورد مقدار و توزیع مکانی ضریب رواناب مورد مقایسه قرار گرفت. نتایج حاصل از این مطالعه نشان داد که در روش جدول ترکیبی، ضریب رواناب به میزان 39 درصد به دست آمده است. حداکثر ضریب رواناب بالقوه در حوضه 55/0 مربوط به مناطق پرشیب و کاربری های کشاورزی حوضه و حداقل مقدار آن 13/0 برآورد شد. بر اساس نتایج، روش توزیعی توانایی نمایش تغییرات مکانی ضریب رواناب را دارد و مقدار متوسط ضریب رواناب در روش توزیعی برابر 39/0 و در روش SCS با دوره بازگشت 50 ساله 29/0 بوده است. در مجموع می توان نتیجه گرفت که دو روش مورد استفاده، دارای تفاوت قابل ملاحظه ای در برآورد ضریب رواناب در مقایسه با مقادیر مشاهداتی نیستند.

    کلید واژگان: سیل خیزی, شماره منحنی, کاربری اراضی, نقشه ضریب رواناب بالقوه}
    Raoof Mostafazadeh *, Amirhosein Ghorbani, Mohsen Zabihi
    Introduction

    Determining the runoff coefficient in a distributed way can be used to identify the runoff producing areas. The runoff coefficient represents the ratio of runoff to total precipitation in different areas, where the previous soil moisture is not taken into account. The runoff coefficient without considering the effect of soil moisture is called the potential runoff coefficient, which is determined based on different parameters in hydrological studies. The changes in the watershed runoff coefficient depend on the topographic characteristics and especially the slope. Assessing the spatial changes of runoff coefficient at the watershed scale is very important for understanding the hydrological cycle under natural and disturbed condition. The location of homogeneous and similar units in terms of hydrological behavior in the watershed is determined and identified by determining the spatial map of runoff production. Meanwhile, determining the watershed response is important in the production of flood runoff volume. It should be noted that the similar units based on hydrological response are usually defined based on runoff production using field measurements. In this regard, the spatial data mapping provides the possibility of preparing a map of the runoff coefficient in a short time and will increase the accuracy of the work. Anthropogenic intervention in the natural water cycle through the destruction of vegetation in watershed areas, land use change, development of impervious surfaces lead to increasing the possibility of flooding in various areas. Various factors affect the occurrence of floods, which can be mentioned the intensity of rainfall, the slope of the land permeability, relief, characteristics of vegetation and different soil conditions. The runoff coefficient is one of the important parameters for estimating the peak flood of hydrological models and identifying important areas of sediment production and pollutants in runoff producing areas. Several factors have been used in determining homogeneous hydrological units with similar runoff coefficient, e.g., rainfall distribution, soil moisture, bedrock depth, evaporation, geology, land use, soil and slope.

    Methodology

    The purpose of this research is to surface runoff potential mapping using combined table and the soil conservation service curve number (SCS-CN) method in the Mohammadabad Katul watershed in Golestan province. The area of study area watershed is 404 square kilometers and a main river length is 30.5 kilometers. The minimum and maximum elevation of the study watershed is 455 and 3671 meters above sea level, respectively. The average annual precipitation of the study watershed is 530 mm, and the average annual temperature is 16.5 centigrade degrees. Also, the average slope of the study area is 41.6%. The land use map of the study area was obtained from the General Office of Natural Resources and Watershed Management of Golestan province and the land use types were modified during the field surveys, then the land use map was digitized in the GIS environment. The soil map of the study watershed was also prepared based on previous studies and then digitized using GIS and the soil map has been prepared. The digital elevation model of the study area with a cell size of 30x30 meters has been obtained from topographic map with a scale of 1:25000. The slope map of the watershed was prepared from the DEM and then classified into four slope classes according to runoff coefficient table. Based on this, the necessary information to determine the runoff coefficient including the land use map, slope and soil texture was prepared. Then, the values of the potential runoff coefficient were determined using the combined table in the study watershed. Also, by incorporating the required layers, the curve number map of the study area has been prepared. The maximum 24-hour precipitation data of the nearest rain gauge station (Fazel abad) has been analyzed. After statistical analysis, the best probability distribution function fitted to the data has been selected for further analysis. Then, the runoff height and the value of the runoff coefficient were determined in 5, 10, 25, 50 years, return periods using the SCS-CN method. In the next step, the results of the combined table method and the SCS method were compared in estimating the amount and spatial distribution of the potential runoff coefficient.

    Result and Discussion

    The results of this study showed that the runoff coefficient was 39% according to the combined table method. The maximum coefficient of potential runoff in the study watershed was estimated to be 0.55, corresponding to the steep and agricultural land use of the study areas. Also, the minimum runoff potential value coefficient was 0.13. Based on the results, the combined distributed method incorporating land use, soil texture, and slope layers has the ability to determine the spatial changes of the runoff coefficient. In the following, the fitted frequency distributions were evaluated based on the goodness of fit criteria, and the Combined Laplace frequency distribution was chosen as the best frequency distribution to calculate the rainfall values in different return periods. The value of the runoff coefficient was 0.29 in 50-year return periods.

    Conclusion

    In the present study, the runoff coefficient map was prepared using the combined table method and SCS-CN method. In this regard, the GIS layers of slope, soil, land use and combined table were used to prepare the potential runoff coefficient map of the watershed. It seems that the calculated runoff coefficient based on the integration of the influencing maps takes into account the main and effective factors on runoff production, and provide an accurate spatial runoff coefficient map. As a concluding remark, it can be said that the combined and SCS-CN methods have provided similar results, but the runoff coefficient numbers provided by the combined method are higher than the SCS method. Considering the effect of several factors, including rainfall characteristics, relief, land permeability, vegetation characteristics and physiography on the flooding of a region, it is necessary to develop a method that can be used to map the runoff coefficient to the flooding map based on the affecting available factors. The integration of different layers in GIS and the use of a combined method is a useful tool for determining the runoff coefficient in ungauged watersheds, which allows the use of the runoff potential map in reducing the possible effects of floods.

    Keywords: Curve Number, Flooding, Land use, Potential runoff coefficient map}
  • بهروز سبحانی*، میلاد منصوری

    درجه حرارت سطح زمین یک موضوع دارای اهمیت و ابزار کنترلی برای مدل آب و هوایی است. در مناطق شهری با توجه به نوع کاربری آن و همچنین پوشش گیاهی کمتر دارای توان جذب زیاد و آلبدو پایین هست. این مناطق دارای دمای سطحی و به تبع آن دمای محیطی بالاتری هستند که هرچه از مناطق مرکزی و متراکم شهر به سمت اطراف و حاشیه برویم از گرما کاسته شده و شرایط دمایی تغییر می کند. در این پژوهش با استفاده از تصاویر ماهواره لندست 5 و 8 دمای سطحی شهر آمل در سال های 1990 و 2020 محاسبه شدند. پیش پردازش های تصاویر ماهواره ای لازم بر روی هر یک از تصاویر اعمال و سپس نسبت به مدل سازی و طبقه بندی تصاویر اقدام شد. ابتدا به منظور بررسی تغییرات کاربری اراضی، نقشه طبقه بندی شده کاربری اراضی برای هر دو سال استخراج و سپس به منظور بررسی تغییرات کاربری طی 30سال، مساحت آن به هکتار عنوان گردید. به منظور پایش دمای سطح زمین نقشه دمای سطحی این شهرستان استخراج شد. نتایج تحقیق نشان داد دما در کاربری های متراکم و صنعتی بالا و قسمت هایی که دارای پوشش گیاهی هستند دارای دمای پایین تری هستند. در طول 30 سال در شهر آمل میزان دمای سطحی افزایش پیداکرده و بر تعداد این نقاط گرم افزوده شده و یک رابطه قوی بین کاربری اراضی و دمای سطحی به وجود آمد. به طوری که در سال2020 کاربری شهری دارای دما 40 درجه سانتی گراد است که به دلیل جذب بیشتر حرارت در نواحی شهری است. درحالی که در کاربری جنگلی دما سطح زمین 28 درجه است که جاذب کمتر حرارت است. این موضوع نقش کاربری های مختلف را در تعیین دمای سطحی نشان می دهد.

    کلید واژگان: دمای سطح زمین, کاربری اراضی, تصاویر لندست, تغییرات کاربری}
    Behrouz Sobhani *, Milad Mansori
    Introduction

    Urbanization changes natural landscapes to human-made spaces and uses. With the expansion of cities, many of these spaces give way to roads, buildings and urban facilities and cause changes in different levels of the city, and these changes have very important effects on weather conditions (Shamsipour et al. 2013: 59). )The development of urbanization is one of the effective factors in increasing the air temperature in urban areas, which causes the creation of thermal islands in these places compared to the surrounding environment. This factor can have a negative effect on air quality and endanger the general health of society. (Mousavi Baighi et al., 2010. 190). What is considered as a fundamental defect in monitoring the temperature of the earth's surface is the lack of sufficient meteorological stations to know the temperature values. Today, this shortcoming has been solved by remote sensing and it can cover a large area of the earth's surface.

    Methodology

    The study area is Amol city. The city of Amol is located in the Mazandaran province and the sides of the Heraz River with a height of 76 meters above sea level at 52 degrees and 21 minutes east longitude and 36 degrees and 25 minutes north latitude and at a distance of 70 kilometers west of Sari, the capital of the province, 18 kilometers south of the Caspian Sea and 6 It is located one kilometer north of Alborz mountain and 180 kilometers northeast of Tehran.In this research, Landsat 8 satellite images and Landsat 5 satellite images were used for 1990 in order to extract the land use map and surface temperature of 2020. In order to remove the effect of cloud cover from the images as well as the high intensity of sunlight, the desired images were taken from the summer season. Google Earth software was used for better accuracy of images, ENVI 5.3 software was used for atmospheric and radiometric corrections, and finally ARC GIS 10.8 software was used to prepare relevant maps.Using the atmospheric correction model (FLAASH), the data were qualitatively controlled and the radiometric error of the satellite images was corrected. In order to obtain a statistical set that represents the spectral pattern of land cover, training data must be selected before supervised classification of images. At this stage, information from the uses and topographical maps of the region were prepared using the visual interpretation of the images for all five floors, to prepare educational data for use in supervised classification operations. Maximum likelihood classification method was used for land use classification. This method is considered a part of the supervised methods for classification and for this purpose it uses a set of training data. In this method, after evaluating the probabilities in each class, the pixels are assigned to the classes that have the most similarity, and if the probability values are lower than the introduced threshold, they are considered as unclassified pixels.After that, the brightness temperature of the sensor is done by converting the digital values of band 6 in Landsat 4 and 5 and also band 10 in Landsat 8 to spectral radiance and converting the spectral radiance to the brightness temperature of the sensor in terms of Kelvin.Then, red and near-infrared bands were used to calculate NDVI to obtain the normalized vegetation difference index. After calculating NDVI we need to get Emissivity. Emissivity is the amount of reflection of a phenomenon relative to the black body. Then the land surface temperature (LST) is calculated. By using LST, it is possible to calculate the temperatures near the surface of the earth. In order to know and evaluate the correctness and accuracy of the classification, the user's accuracy, overall accuracy and Kappa coefficient were calculated in 1990 and 2020.

    Conclusion

    In this research, in the first step, the classification and the resulting changes were done in a specific time frame in Amol city and its surroundings. The classification results indicate that the classification in both periods, especially in 2020, was highly accurate, and its kappa coefficient and overall accuracy were at their highest coefficient, i.e. 100.After classification, the changes obtained in the area were examined for a period of 30 years and the changes were extracted for each land use in terms of hectares. The change of use from agriculture to the city and also from the city to roads and streets have the most changes. These changes indicate that the increase in urban use has caused a decrease in agricultural use and the size of urban areas has increased.Using Landsat satellite images, the temperature of the earth's surface has been studied in relation to land use and the results showed that the temperature is different in different uses. The highest temperature recorded for the years 1990 and 2020 in Amol city is related to urban use, the recorded temperature of which is 32.6 and 40.5, respectively, which shows the concentration of heat in urban areas. Urban use has the highest temperature due to the presence of man-made factors and heat absorbers such as asphalt, concrete and the presence of machinery. Also, the presence of tall buildings acts as a barrier to the heat escaping to the surroundings and in some way traps the heat inside the cityWith the development of urbanization in Amel city, a significant part of the area of natural and forest areas has been replaced by industrial areas, buildings and other infrastructures. The lowest temperature recorded in Amol city is related to forest use with 23.8 and 28.4 degrees Celsius. In forest areas, due to high albedo, high humidity and more open space, the temperature is lower and heat absorption is low there.The relevant researchers and experts in the region can use the results of this research to obtain information about the temperature of the earth's surface, land use, and also the changes that have occurred in the region, In order to predict the future situation of the region, they will take appropriate and correct policies.

    Keywords: Land surface temperature, Land use, Landsat images, Use changes}
  • مریم ناظمی جلال*، مرضیه علی خواه اصل، الهام فروتن
    زمینه و هدف

    استفاده و مدیریت بهینه یک سرزمین نیازمند اطلاعات بهنگام و درست می باشد. یکی از مهمترین منابع اطلاعاتی در مدیریت منابع طبیعی، نقشه های پوشش اراضی است. هدف از انجام این پژوهش، تهیه نقشه های پوشش اراضی منطقه کتالان برای بررسی تغییرات صورت گرفته طی 12 سال گذشته می باشد.

    روش بررسی

    در انجام این تحقیق داده های ماهواره لندست سنجنده OLI سال 2013 و سنجنده ETM سال 2001 به کارگرفته شد و پس از انجام تصحیحات لازم بر روی تصاویر، از GPS و نقشه های توپوگرافی به منظور بازدید صحرایی منطقه و برداشت نقاط تعلیمی، استفاده شده است. نقشه های پوشش اراضی با استفاده از روش طبقه بندی نظارت شده با الگوریتم حداکثر احتمال تهیه گردید.

    یافته ها

    بر اساس نتایج به دست آمده، منطقه مورد مطالعه دارای 6 طبقه شامل: اراضی زراعی آبی، اراضی زراعی دیم، اراضی زراعی رها شده، رخنمون سنگی، مرتع و معدن می باشد. دقت کلی و ضریب کاپا برای نقشه پوشش اراضی سال 2013، به ترتیب برابر 11/86% و 82/0و برای سال 2001 به ترتیب برابر با 26/78% و 71/0 به دست آمد.

    بحث و نتیجه گیری

    نتایج تحقیق نشان می دهد که اراضی زراعی آبی، اراضی رها شده و طبقه مرتع از سال 2001 نسبت به سال 2013 به ترتیب 84/1 % و 29/1 % و 21/1% افزایش سطح داشته است و کلاس اراضی زراعی دیم و برو ن زد سنگی به ترتیب 09/5 % و 62/0% کاهش یافته است. همچنین طبقه معدن در سال 2001 وجود نداشته و در سال 2013، 3939/49هکتار معادل 36/1 درصد از مساحت منطقه را به خود اختصاص داده است.

    کلید واژگان: کتالان, سنجش از دور, طبقه بندی نظارت شده, پوشش اراضی}
    Maryam Nazemi jalal *, Marzieh Alikhah-Asl, Elham Forootan
    Background and Objective

    Updated and correct information is necessary for using and optimized managing of a land. Land cover map is one of the most important information resources in natural resource management. The goal of this research is to provide Katalan land cover map for investigating land use changes during 12 years in this area.

    Material and Methodology

    For this purpose, satellite images such as Landsat ETM 2001 and OLI 2013 were used after performing necessary corrections whereas; GPS and topographic maps were implemented for surveying fields and gathering trained samples. Land cover maps were provided using supervised classification method with maximum likelihood algorithm.

    Findings

    The results of this study revealed that the study area comprises six classes viz. irrigated farm land, rainfed farm land, bare land, rock stone, range land and mine class. The overall accuracy and kappa coefficient for 2013 map were estimated 86.11% and 0.82, respectively and theses values for 2001 land use map were 78.26%, and 0.71, respectively.

    Discussion and Conclusions

    The results of this research revealed that the class of farm land, bare land and range land were increased 1.84%, 1.29%, and 1.21%from 2001 to 2013, and the class of rock stone and rainfed farmland were decreased 5.09%, and 0 .62%, respectively. Also, there was not mine class in 2001 but this class was 1.36% equivalent to 49.3939 hectare of the whole area in 2013.

    Keywords: Katalan, Remote sensing, supervised classification, land cover}
  • R. Setiowati, R.H. Koestoer *, R.D. Andajani
    BACKGROUND AND OBJECTIVES
    Urban green infrastructure, specifically green open spaces, is becoming increasingly significant in rapidly urbanizing areas. These spaces offer environmental, social, and economic advantages to urban ecosystems, thereby increasing community health and well-being. However, their economic value is often overlooked in urban planning. This study aims to conduct an economic valuation of green spaces by introducing the hedonic price model to equip decision-makers with a thorough and informed perspective.
    METHODS
    A questionnaire created through Google Forms was distributed through a social media survey conducted from March to April 2021. The data collected from 1592 respondents in Jakarta were analyzed through a cluster analysis using the statistical package for social sciences software. The hedonic price model with ordinary least squares regression was adopted to create a valuation model for the green spaces in 42 districts and 239 sub-districts across the five administrative cities.
    FINDINGS
    This study empirically shows that parks and urban forests increase land prices by 9.2, 17.1, and 19.2 percent, while cemeteries decrease them by 15 to 37.6 percent. Unlike most hedonic price model studies on the global north countries, which can be found in the literature, this work does not establish statistically significant relationships among urban forests, parks, cemeteries within a 0–500 meter radius, and land prices in Jakarta, but examines the economic value of green spaces, including their impact on land values and tax revenues. The land value increase is caused by the implementation of a beneficiary zoning levy within a designated impact zone of 0.5–2 kilometers. This study suggests policy implications, including the exploration of alternative financing mechanisms and the consideration of public preferences in urban development and financing policies.
    CONCLUSION
    The applicability of the hedonic price model in Jakarta's mature and privatized land market is confirmed in this work, proving the importance of considering environmental factors and green spaces in land transactions and conversion, property development, conservation, and urban green space design. The results provide valuable information to policymakers, property developers, and land use planners, thereby preventing the undervaluation of green spaces and facilitating informed decisions on planning and public investment. Urban and built environmental management can significantly benefit from these findings, particularly when considering the aspects of green space size, social functions, and ecosystem services to enhance Jakarta's planning and management practices.
    Keywords: Economic Valuation, Green open space (GOS), Hedonic price model (HPM), Land value, Urban Sustainability}
  • E.S. Siregar, S.U. Sentosa, A. Satrianto *
    BACKGROUND AND OBJECTIVES
    This study aims to examine the endogenous variable, low-carbon development, and valuate its influencing factors, given its pivotal role in environmental protection amid climate change concerns and economic growth. Low carbon development is a new platform to maintain economic growth through reducing carbon emissions and reducing the use of natural resources, because it was predicted that reducing emissions will increase economic growth while preventing forest loss, improving air quality and living standards, and reducing mortality rates.
    METHODS
    Utilizing a quantitative method, this study integrates a novel viewpoint by combining low-carbon development with related emission factors. The study utilizes secondary data, specifically time series data spanning 31 years from 1991 to 2021, which were analyzed using regression study methods. The factors being examined include capital formation, deforestation, land transportation, agricultural land, and industrialization.
    FINDINGS
    Findings reveal that low-carbon development in North Sumatra is influenced significantly by capital formation, deforestation, agricultural land, and industrialization, with land transportation showing no substantial impact. Capital formation has a favorable impact on low-carbon development. But, deforestation, land transportation, agricultural land and industrialization have a negative impact on low-carbon development. Together, these determinants account for 77.55 percent of the variance. Capital formation contributes 19.8 percent, deforestation 15.6 percent, agricultural land 19.0 percent, and industrialization 18.9 percent to low-carbon development.
    CONCLUSION
    The hypothesis established in this study is accepted. To foster low-carbon development in North Sumatra, specific attention is required from local governments. Capital formation is vital. Measures include controlling interest rates, supporting businesses, fostering an investment-friendly climate, ensuring security, and integrating environmental sustainability considerations into project implementation to curb carbon emissions. Prevention of deforestation involves tightening land clearance licenses and enhancing institutional quality through environmental protection and property rights legislation. The   government must strive for promoting eco-friendly agricultural practices with mitigated through outreach programs involving experts who educate farmers on minimizing emissions, reducing carbon emissions from pesticide with using biochar sourced from empty palm fruit bunches and also rice straw which is very easy to obtain at a low cost and is environmentally friendly, and emphasizing environmental preservation policies in the industrial sector like industrial transformation efforts with an effective approach to reducing carbon emissions such as restructuring various aspects of industrial activities, including investment, final demand, intensity and production methods. The implementation of tax emissions and strategic interventions increases the likelihood of realizing low-carbon development in North Sumatra, aligning with sustainable development goals.
    Keywords: Agricultural land, Capital formation, Deforestation, Industrialization, Land transportation, Low carbon development}
  • M.K. Rosyidy, E. Frimawaty *
    BACKGROUND AND OBJECTIVES
    Oil palm is one of the crops that has an essential role in Indonesia's engineering field. This condition has led to oil palm plantation intensification, which has been extensive to deforestation in Indonesia, including Jambi province. The main aim of this investigation is to evaluate deforestation and land change affected by oil palm expansion conducted by smallholders, which influences environmental change using remote sensing combined with a geographic information system approach. This study utilizes the change of oil Palm in spatial-temporal (spatial and temporal) in Jambi province related to land change and environmental impacts.
    METHODS
    This research uses data from Landsat 8 satellite imagery. The land cover classification was done using the Maximum Likelihood approach, while the overlay method was used for land change analysis. Accuracy assessment of classification results uses a confusion matrix taking into account overall accuracy and Kappa Hat. Within the field observation, the validation class is the oil palm class, using documentation and plotting using the global positioning system, and other classes are validated using the Region of Interest collected through Google Earth. This research uses Aviation Reconnaissance Coverage Geographic Information System 10.1 software to transform the categorization results into vector data.
    FINDINGS
    This study shows that the landcover classification results have high accuracy. This study shows that the area of oil palm land from 2015 to 2019 has increased along with a decrease in land used, such as forests and others. The area of oil palm land 2014 was 2,071,345 hectares, while the area in 2019 was 2,110,545 hectares. In other words, there was an increase in land cover due to land clearing and deforestation, namely 39.2 thousand hectares. The built-up area has also increased in the last five years, namely 165,358 hectares. The number of oil palm plantations tends to be greater in relatively plain areas compared to areas with relatively high altitudes and steep slopes. Small farmers'''' area of oil palm land increased by 1,000 hectares in 2014-2018. The most significant increase occurred in 2016-2017, around 38,889 hectares.
    CONCLUSION
    This study demonstrates that using Landsat 8 imagery combined with GIS approaches provides the optimal method for an in-depth analysis of land cover changes related to oil palm expansion and land clearing that occur on a broader spatial scale and temporal in Jambi Province. This study shows that smallholder oil palm plantations in the Jambi region play an important role in increasing deforestation in Jambi Province, especially in Indonesia. This study is expected to serve as a valuable resource for informing policy decisions aimed at addressing the issue of deforestation resulting from the prospective increase of oil palm crops in the forthcoming period.
    Keywords: geographic information system (GIS), Land change, Oil palm, Remote Sensing, Spatiotemporal}
  • B.H. Narendra *, O. Setiawan, R.A. Hasan, C.A. Siregar, Pratiwi, N. Sari, A. Sukmana, I.W.S. Dharmawan, R. Nandini
    BACKGROUND AND OBJECTIVES

    Flooding is the most frequent hydrological disaster which greatly impacts humans and the environment. Lombok, a small tropical island, experiences severe flooding almost yearly. Flood susceptibility mapping is important to determine the priority watershed in implementing flood mitigation action, including improving the spatial planning in watershed management. Several methods of determining flood susceptibility require the support of long data series and a variety of monitoring equipment in the field where not every region has the resource capacity. Compared to other methods that require the support of long data series and a large number of evenly distributed monitoring equipment, the geomorphometric parameters and land use/cover in a watershed are closely related to the hydrological responses and are potentially applicable in flood susceptibility mapping. This research aimed to classify the watershed flood susceptibility on a small island based on the geomorphometric characteristics and land use/land cover of the watershed.

    METHODS

    This study was carried out on Lombok Island, located in southern Indonesia, representing a small island in the tropical region. Watershed classification was carried out using 24 geomorphometric variables and land use/land cover, representing aspects of the river network, geometry, texture, and watershed relief. The principal component analysis approach was carried out to determine the most significant variable, and the weight of each variable was determined using the weighted sum approach method. Then, compound values were calculated based on the weighted values and preliminary ranking to indicate the flood susceptibility levels, which were divided into five classes.

    FINDINGS

    The analysis found that the variables most related to flood events are the total number of rivers, relief ratio, elongation ratio, river density, stream frequency, and dry agricultural land use. These most related geomorphometrics indicate that the watersheds with higher flood susceptibility have low rock permeability, relatively low infiltration capacity, and relatively high surface runoff, thus triggering flooding. The flood susceptibility mapping classified 16 watersheds as having very high flood susceptibility. This research shows that analysis of the geomorphometric characteristics and land use/land cover can be relied upon to determine the flood susceptibility level, which is useful in spatial planning and flood disaster mitigation.

    CONCLUSION

    Geomorphometric characteristics and land use/land cover can be used to determine a watershed's hydrological characteristics or behaviour. Based on the geomorphometric characteristics of the watersheds on Lombok Island, some identifying variables that are highly related to flood processes were obtained. Based on these characteristics, watersheds with high and very high flood susceptibility levels have low rock permeability, relatively low potential infiltration capacity, and relatively high surface runoff potential. Flooding still occurs despite good forest cover because the geomorphometric characteristics of the watershed also play a major role in flood events.

    Keywords: Flood susceptibility, Hydrological Response, Geomorphometrics, Land use, land cover}
  • I. Ridwan *, S. Kadir, N. Nurlina
    BACKGROUND AND OBJECTIVES

    The condition of the watershed area, particularly the Tabunio Watershed, is one with priority treatment due to the condition of the land where it is located, which qualifies for the “very high recovery” category with a critical land area of 19,109.89 hectare. Moreover, the diminishing water absorption also results in flooding during the rainy season and drought in the dry season. Environmental damage in the Tabunio Watershed is exacerbated by the existence of traditional gold mining and has become a concern for many parties. With this in mind, the perceived increase in natural disasters, such as floods, landslides, and droughts from year to year requires an evaluation of land degradation in the Tabunio Watershed.

    METHODS

    The objective of this study was to monitor and simulate the spatial and temporal aspects of land degradation in the Tabunio Watershed. It was suggested that a complete land degradation index be developed to capture the spatial and temporal aspects of land degradation between the years 2005 and 2020. This index integrates land use land cover, vegetation coverage, soil erosion, and soil moisture content.

    FINDINGS

    The proposed comprehensive land degradation index in this study demonstrated that (a) the land degradation index, which successfully monitored the spatio-temporal aspect of land degradation (kappa coefficient > 0.73 and overall accuracy > 86 percent), is regarded as having high accuracy. (b) In comparison to the individual indices, the land degradation index is capable of revealing land degradation in a more comprehensive manner. (c) land degradation index is readily transferable and applicable to other study areas due to the fact that all of its land degradation indices can be quickly extracted from remotely sensed imagery. (d) land degradation index can be used in a wide variety of contexts, which also accounts for the provision of quantitative predictions with regard to the possibility of land degradation. (e) The rate of land degradation will generally increase from 2005 to 2020, with 2010 being the most extreme year.

    CONCLUSION

    The proposed comprehensive land degradation index method is capable of describing the spatial and temporal aspect of land degradation from 2005 to 2020 in the watershed area. Moreover, the proposed approach shows that the level of land degradation from 2005 to 2020 normally increases, recording the extreme years as the 2010s. In addition, in most years, the amount of land degradation was moderate, only few of which had severe or extreme degradation. As a consequence of this, some land degradation management measures ought to be created in advance, guaranteeing the protection of this vital region, which is a source of freshwater. The study provides a substantial understanding of the effect of land degradation on sustainable environment management and development in the watershed.

    Keywords: land degradation index, land use, land cover (LULC), Soil erosion, Soil moisture content, vegetation coverage}
  • مژده بروغنی، سید حامد میرکریمی*، مرجان محمدزاده، سپیده سعیدی
    امروزه جوامع با انبوهی از مشکلات محیط زیستی مواجه هستند و مدیریت و حل این مشکلات، لزوم همکاری جمع بزرگی از افراد را می طلبد. باتوجه به این که هر گونه توسعه ای بر مدیریت سرزمین تاثیرگذار است، تحقیقات اخیر اهمیت زیادی به مشارکت افراد در مدیریت برنامه ها و حل مسایل داده اند. راه کارهای مختلفی جهت مدیریت موثر سرزمین وجود دارد که کمک و مشارکت همه جانبه افراد را می طلبد، این مسیله با استفاده از روش جمع سپاری که افراد را در یک شبکه بزرگ گرد هم می آورد، قابل حل است. جمع سپاری امکان مشارکت افراد را در یک  فراخوان عمومی فراهم آورده و کمک می کند تا افراد صرف نظر از موقعیت مکانی که در آن واقع هستند، با دسترسی به اینترنت بتوانند نظرات، ایده ها، اطلاعات، توانایی ها و آگاهی های خود را به اشتراک گذاشته و نقش موثری در مدیریت سرزمین داشته باشند. هدف از مطالعه حاضر، معرفی روش جمع سپاری، مزایا و معایب آن و همچنین معرفی برخی از برنامه های کاربردی مبتنی بر این روش و کاربرد آن ها در مدیریت سرزمین است. نتایج تحقیق حاضر و مرور مطالعات و پژوهش های مرتبط با روش جمع سپاری در مدیریت سرزمین، بیانگر تاثیر قابل ملاحظه مشارکت افراد در حل مسایل محیط زیستی و اعمال مدیریت صحیح است. چنین مشارکت هایی باعث کاهش هزینه ها و اطلاع رسانی و کمک رسانی سریع خواهد شد.
    کلید واژگان: مدیریت سرزمین, جمع سپاری, مشارکت, فراخوان عمومی, رای گیری جمع, خردکاری}
    Mozhdeh Boroughani, Seyed Hamed Mirkarimi *, Marjan Mohammadzadeh, Sepeideh Saeidi
    Societies nowadays encounter with a large number of environmental problems. Management of these problems requires involvement of a large number of people. Such issues can be solved using crowdsourcing methods which brings people together in a large network. Considering the fact that any development will affect land management, recent studies have given more attention to public participation in program management and problem solving. There are various approaches for effective land management that need overall community participation. In this regard, crowdsourcing methods have provided the possibility of public participation in decision making that help individuals to have an effective role in land management. People participating in this process can share their opinions, ideas, information, abilities and awareness through internet regardless of their physical location. The purpose of this study was to introduce crowdsourcing, its advantages and disadvantages, and some of crowdsourcing-based applications and their functions in land management. The results of this research based on the literature review showed the significant impact of public participation in decision making on environmental issues and performing proper management strategies. Such participation will help reduce costs and provide quick information and assistance.
    Keywords: Land Management, Crowdsourcing, Participation, Public Participation, Crowd voting, Micro-task}
  • Jafar Mohammadi, Ebrahim Fataei, Akram Ojaghi

    Increasing population growth and civilization have caused great impacts on water quality. Among these, changes and excessive exploitation of land use have led to changes in the surface water quality to provide human needs. Therefore, the present study investigated the effects of land use on water quality using a spatial-statistical approach. To this end, the water quality data of 22 water quality-sampling stations were applied in the Qarasu watershed in Ardabil in 2013, Iran. Then, spatial analysis was conducted, including land use classification maps, watershed mapping and overlaying maps using GIS. Finally, correlation and multiple linear regression analysis were used to determine the relationship between water quality and land use variables. Pearson's correlation coefficient showed proper percentages of vegetation cover, agricultural lands, woodlands, residential users, barren land and forest as well as weak pastureland have significant correlation with water quality variables. Multiple linear regression analysis with stepwise approach also indicated that of dependent parameters as water quality variables, the parameters of pH, Cl, Ca, Mg, Na and SAR are associated with land use as independent parameters including irrigated agriculture, first-grade pasture, third-grade pasture, woodlands, moorland, forest and residential users. Furthermore, validation of the model based on two models of the survey of predicted and actual values as well as root-mean-square error (RMSE) demonstrated good accuracy of the resulting model.

    Keywords: Water Resources Management, Land Use, Water Quality, Correlation}
  • آرزو معظمی، جمال قدوسی*، علی اصغر آل شیخ، سعید سلطانی
    زمینه و هدف

    امروزه در خصوص توسعه مناطق شهری و استفاده از اراضی در آنها دو اختلاف نظر و برخورد رویکردی شامل روند و شدت تغییر کاربری اراضی و تغییرات حفاظ روی زمین مطرح است که تبیین‏کننده خصوصیات و ویژگی های رشد و گسترش شهرها و پایداری زیست محیطی آنها می باشد. روند فعلی رشد و گسترش مناطق شهری و مسکونی و تغییرات منطقه ای و ناحیه ای ناشی از آن بعنوان یکی از چالش های اصلی برای تعریف راهبردهای توسعه ای در مناطق شهری مطرح و معرفی شده است.

    روش بررسی

    امروزه دستیابی به روش های مناسب اندازه گیری و ارزیابی و برنامه ریزی در کلیه سطوح و مرتبط با آن در مناطق شهری، مورد حمایت و پشتیبانی مدیران در مناطق شهری می‏باشد. اگر چه در مدل ها و روش های موجود برای آمایش سرزمین و تخصیص اراضی برای کاربری های مختلف عواملی مانند موقعیت مکانی و طبیعی، خصوصیات زیست محیطی، اکولوژیکی، ادافیکی، شرایط اجتماعی، فرهنگی، اقتصادی و حتی سیاسی منظور شده و مورد توجه قرار گرفته اند اما ملاحظه می شود که در برخی از آنها  مانند مدل های CLUE-S و AEZ، تنها به تغییر کاربری اراضی از جمله کشاورزی و اراضی مرتعی و جنگلی، توجه گردیده است.به طوری که در حال حاضر اختلاف نظرهادر خصوص مباحث مرتبط با آمایش مناطق شهری در رابطه با تخصیص اراضی، رخدادهای تحقیقاتی در زمینه استفاده از اراضی در قالب اصول و مفاهیم آمایش سرزمین بیش از پیش مورد تاکید و توجه قرار گرفته است.

    یافته ها

    در تحقیق حاضر با هدف مدل‏سازی تخصیص و پهنه بندی اراضی شهری در قالب مطالعه موردی در شهر چادگان واقع در استان اصفهان اقدام به مدل سازی با استفاده از تلفیق روش های مدل سازی مکانی وتصمیم گیری چندمشخصه ای با روش های کارت امتیازی متوازن و تولید پاک در محیط سیستم های اطلاعات جغرافیایی شده است.

    بحث و نتیجه گیری

    خروجی حاصل از تحقیق ارایه مدل توصیفی مبتنی بر امتیاز دهی به شاخص‏های 22 گانه مربوط به 4 معیار یا مولفه اجتماعی،زیست محیطی، اکولوژیکی و اقتصادی است. به نحوی که با شناسایی خصوصیات و ویژگیهای هریک از مولفه ها وتهیه نقشه های موضوعی مربوط به آنها مبتنی بر امتیاز یا نمره هریک از شاخص‏های 22 گانه در محیط سیستم های اطلاعات جغرافیایی می‏توان اقدام به تخصیص و پهنه بندی اراضی شهری در 4 وضعیت شامل نا مطلوب، نسبتا مطلوب، مطلوب و بسیار مطلوب بر اساس نوع کاربرهای مورد نظر در مناطق شهری نمود.

    کلید واژگان: تخصیص اراضی, آمایش و پهنه‏ بندی اراضی شهری, مدل‏سازی مناطق شهری}
    Arezo Moazami, Jamal Ghoddousi *, Ali Asghar Alshaeikh, Saeid Soltani
    Background and Objective

    Today, there are two differences of opinion and approach review including the trend and intensity of land use change and land protection changes regarding the development of urban areas and the use of land, which explain the characteristics of the growth and expansion of cities and their environmental sustainability. The current trend of growth and development of urban and residential areas and the resulting regional changes have been proposed and introduced as one of the main challenges to define development strategies in urban areas.
    Material and

    Methodology

     Today, achieving appropriate methods of measurement and evaluation and planning at all levels is supported by managers in urban areas. Although different factors such as location and natural, environmental, ecological, edaphic characteristics, social, cultural, economic and even political conditions are taken into consideration in the existing models and methods for land preparation and land allocation for different uses, it can be stated that in some of them, such as CLUE-S and AEZ models, only the change of land use, including agriculture, pasture and forest lands, has been considered. Now, the arguments about the planning of urban areas in relation to land allocation, research events in the field of land use in the form of principles and concepts of land planning have been more emphasized.

    Finding

    The present study aimed to model the allocation and zoning of urban land in the form of a case study in the city of Chadegan, located in Isfahan province, and also the modeling was performed using the integration of spatial modeling methods and multi-attribute decision making with balanced score card methods and clean production in the environment of geographic information systems.
    Discussion and

    Conclusion

    The result of the research presented a descriptive model based on scoring 22 indicators related to 4 social, environmental, ecological and economic criteria or components. Thus, by identifying the features and attributes of each of the components and preparing thematic maps related to them based on the scores of each of the 22 indicators in the environment of geographic information systems, it is possible to allocate and zone urban lands in 4 situations including unfavorable, relatively favorable, favorable and highly favorable according to the type of users in urban areas.

    Keywords: Land allocation, planning, zoning urban lands, urban areas modeling}
نکته
  • نتایج بر اساس تاریخ انتشار مرتب شده‌اند.
  • کلیدواژه مورد نظر شما تنها در فیلد کلیدواژگان مقالات جستجو شده‌است. به منظور حذف نتایج غیر مرتبط، جستجو تنها در مقالات مجلاتی انجام شده که با مجله ماخذ هم موضوع هستند.
  • در صورتی که می‌خواهید جستجو را در همه موضوعات و با شرایط دیگر تکرار کنید به صفحه جستجوی پیشرفته مجلات مراجعه کنید.
درخواست پشتیبانی - گزارش اشکال