ارزیابی تطبیقی آسیب‌پذیری توده‌های کارستی شاهو و مانشت با استفاده از روش cop

ارزیابی آسیب پذیری امری مهم برای مدیریت پایدار منابع آب کارست و برنامه ریزی استفاده از زمین است. آبخوان های کارستی شاهو و مانشت نقش حیاتی در تامین آب شرب و کشاورزی جوامع محلی اطراف خود دارند. هدف این پژوهش ارزیابی آسیب پذیری در دو منطقه کارستی با استفاده از روش cop است. از پارامترهای هیدروژئولوژیکی از جمله ضریب آلفا و حجم ذخیره دینامیکی برای مشخص کردن نوع سیستم کارستی استفاده گردید. همچنین با استفاده ضریب تعیین بمنظور تعیین فاکتورهای مهم در آسیب پذیری این مناطق مورد بررسی قرار گرفتند. نتایج نشان می دهد که آبخوان های کربناته دارای سیستم جریان افشان آسیب پذیری کمتری نسبت به آبخوان های کارستی دارای سیستم جریان مجرایی دارند. در کارست های مجرایی فاکتورc  همبستگی مثبت بالایی را با شاخص آسیب پذیری دارد در حالی که در کارست های افشان فاکتور o همبستگی بیشتری با این شاخص دارد. عامل c به علت وسعت زیاد پهنه های کارست تکامل یافته در منطقه شاهو نقش اصلی را در بالابودن میزان آسیب پذیری این منطقه نسبت به توده کارستی مانشت دارا می باشد. همچنین نتایج طبقات آسیب پذیری نشان می دهد که 43 درصد توده کارستی شاهو در طبقه آسیب پذیری زیاد و متوسط واقع شده است و در مقابل مساحت این طبقات در منطقه مانشت به مراتب کمتر (27 درصد) است. وجود اشکال کارستی توسعه یافته از جمله دولین ها، مگاکارن ها، غارهای عمیق و درزه و شکاف فراوان در منطقه شاهو دال بر توسعه یافتگی بیشتر این منطقه نسبت به توده کارستی مانشت می باشد. در نهایت می توان گفت ارزیابی آسیب پذیری آبخوان های کارستی چنانچه با مطالعات ژئوفیزیکی آبخوان ها و همچنین اجرای صحیح سیاست های برنامه ریزی استفاده از زمین همراه باشد، نتایج قابل توجهی را ارائه می دهند.

comparative evaluation of the vulnerability of shahu and manshet karst masses using the cop method

vulnerability assessment is important for sustainable management of karst water resources and land use planning. shahu and manshet karst aquifers play a vital role in supplying drinking water and agriculture to local communities around them. the aim of this research is to evaluate vulnerability in two karst regions using the cop method. hydrogeological parameters including alpha coefficient and dynamic storage volume were used to determine the type of karst system. they were also investigated using the coefficient of determination in order to determine the important factors in the vulnerability of these areas. the results show that carbonate aquifers with spray flow system are less vulnerable than karst aquifers with channel flow system. in conduit karsts, factor c has a high positive correlation with the vulnerability index, while factor o has a higher correlation with this index in oozing karsts. due to the large extent of developed karst areas in shaho region, factor c has the main role in the high level of vulnerability of this region compared to the manshet karst mass.also, the results of the vulnerability classes show that 43% of the shahu karst mass is located in the high and medium vulnerability class, and in contrast, the area of ​​these classes in manshet region is much less (27%). the presence of developed karst forms, such as dolines, megakarns, deep caves and many cracks and crevices in the shahu region indicates that this region is more developed than the manshet karst mass. finally, it can be said that the vulnerability assessment of karst aquifers, if accompanied by geophysical studies of aquifers as well as the correct implementation of land use planning policies, will provide significant results. extended abstract introductionthe protection of environmental resources hinges on analyzing the risks of human activities to facilitate sustainable development. risk involves factors such as hazard, vulnerability, exposure, and mitigation. for groundwater management, aquifer vulnerability maps are crucial, as they predict risks and prevent land misuse. karst aquifers, in particular, are highly sensitive to pollution due to rapid transport times to saturated and unsaturated zones.karst aquifers feature unique landforms that increase pollution risk by reducing protective cover. despite the existence of various vulnerability models, a universal model applicable to all aquifers is lacking, complicating the determination of appropriate locations for vulnerability mapping. researchers conduct extensive statistical analyses to identify relevant vulnerability indicators for each aquifer. for instance, sensitivity analysis helps ascertain the significance of different factors in vulnerability indices.recent studies reveal that factors weakening environmental capacity strongly correlate with vulnerability indicators in fractured carbonate aquifers, while surface current concentration factors correlate more in karst aquifers. for example, nukum and hützel found significant differences in vulnerability maps using mean square analysis, emphasizing the importance of classification consistency.in northern iran’s darfak region, research using the copkat model identified microbial and nitrate pollution from agriculture and livestock as major vulnerability sources. similarly, in northern italy, the cop+k model proved effective in highly sensitive karst systems. other studies have linked vulnerability maps to groundwater quality maps.this research employs spatial and statistical analyses to create vulnerability maps using the cop method for two zagros karst sites in iran, a country facing a water scarcity crisis. with 11% of iran’s surface covered by high-quality groundwater-containing carbonate rocks, protecting these resources is critical. the studied areas differ in lithology, hydrogeology, climate, and karst evolution.over the past decade, western iran’s semi-arid regions have faced severe pressure on karst water resources from overexploitation, pollution, and droughts. these vital water sources, essential for drinking and agriculture, are increasingly polluted by human activities. given their geological and climatic context, safeguarding these aquifers through vulnerability assessment and management strategies is imperative..methodologythis applied development research uses various data sources, including a digital elevation model (10m resolution), geological maps (1:100,000), soil maps (1:250,000), vegetation maps, weather station rainfall and temperature statistics, karst spring discharge statistics, and field data. the cop method is employed to assess site vulnerability, based on concepts integral to european karst aquifer studies (goldscheider et al., 2004). developed under the european cast 620 project, the cop model evaluates aquifer vulnerability and creates risk maps by considering three factors: covering layers (o), flow concentration layer (c), and precipitation regime (p).the covering layer includes soil thickness, porosity, permeability, and lithology of the unsaturated zone. the flow concentration factor pertains to areas with different infiltration conditions, especially where water infiltrates through protective layers.