Environmental Erosion Research

fa ارزیابی شاخص‌های کیفیت خاک در تیپ‌های مختلف خاک دشت ارومیه Evaluation of Soil Quality Indicators in Different Types of Soils in Urmia Plain مدیریت و کنترل اثرات فرسایش محیطی پژوهشي Research ارزیابی کیفیت خاک، یکی از مسائل قابل توجه در مدیریت پایدار خاکها به منظور تولید بهینه کشاورزی و حفظ منابع طبیعی است. استفاده از شاخصهای کیفیت خاک نیز ابزار مفیدی برای تعیین و مقایسه کیفیت خاکها به شمار میرود. هدف از این تحقیق، کمی کردن این شاخص با استفاده از تحلیلهای چند متغیره در تیپهای مختلف خاک دشت ارومیه است. در این پژوهش با استفاده از روش تجزیه به مؤلفههای اصلی (PCA)، از میان 22 ویژگی مؤثر بر کیفیت خاک (TDS) شش ویژگی به عنوان حداقل ویژگیهای مؤثر بر کیفیت خاک (MDS) تعیین شد. سپس این کیفیت با استفاده از دو شاخص تجمعی کیفیت خاک (IQI) و شاخص کیفیت نمورو (NQI) و هر کدام در دو مجموعه ویژگیهای خاک TDS و MDS ارزیابی شد. از بین پارامترهای اندازهگیری شده، پ هاش (pH) کمترین ضریب تغییرات (5/2 درصد) و شوری (EC) بیشترین ضریب تغییرات (6/154 درصد) را در منطقه داشت. نتایج نشان داد که به طور کلی، خاکهای منطقه از نظر شاخصهای مورد مطالعه در بخشهای منتهی به دریاچه، دارای محدودیت است و بین IQIa TDS و IQIa MDS و بین NQI TDS و NQI MDS همبستگی معنیدار وجود دارد. این امر نشان میدهد که مجموعه MDS تعیین شده، به خوبی میتواند نماینده مناسبی از TDS باشد. بررسی شاخص کیفیت خاک نشان داد که خاکهای این منطقه <a name="_Hlk118635722">عمدتاً دارای درجه کیفیت </a>II (57 درصد) است. بیشترین مقدار میانگین شاخص کیفیت خاک انتخاب شده نیز مربوط به حالت MDS در مدل IQI با مقدار 79/0 در تیپ خاک Fluventic Haploxerepts و کمترین مقدار آن، مربوط به حالت TDS در مدل NQI با مقدار 28/0 در تیپ خاک Typic Halaquepts محاسبه شد. بررسی ضریب همبستگی بین شاخص کیفیت خاک با دسته کل و حداقل دادهها نشان داد که ضریب همبستگی هر دو مدل IQI و NQI برابر با (48/0R2=) است. در نهایت، شاخص IQI در مجموعه حداقل دادهها (MDS)، دقت و حساسیت بیشتری برای ارزیابی کیفیت خاک دارد. در مجموعه حداقل دادهها نیز به ترتیب ویژگیهای درصد شن، نسبت جذب سدیم، ظرفیت تبادل کاتیونی، فسفر قابل جذب، کربنات کلسیم فعال و غلظت نیکل، وزن بالاتری دارد. استفاده از مؤثرترین ویژگیهای خاک در مطالعات ارزیابی کیفیت آن، ضمن کاهش زمان مطالعات خاکشناسی زمینه صرفهجویی اقتصادی را در بحث پایش و بهرهبرداری پایدار از اراضی کشاورزی فراهم میکند. 1- Introduction One of the important issues in the sustainable management of soils in order to optimize the agricultural production and preserve natural resources is the assessment of soil quality.  Soil quality is the capacity of a specific kind of soil to function to sustain plant and animal productivity, maintain or enhance water and air quality, and support human health and habitation. It is also considered one of the most important factors investigated in the assessment of soil management. Knowledge of quality changes is necessary for sustainable soil management. Since soil quality cannot be measured directly, it must be obtained from the relevant characteristics. Soil quality characteristics are sets of measurable soil characteristics that are sensitive to land use change, management, or conservation operations. Using soil quality indicators is a useful tool to determine and compare soil quality. The purpose of this research is to quantify the soil quality index using multivariate analysis in different soil types in Urmia Plain. 2- Methodology In this research, according to the semi-detailed soil studies of Urmia plain, 24 soil profiles from different soil units of this area, which are mostly under garden and agricultural use, were excavated, described, sampled, and classified, and 96 samples were also collected from soil solum. 2 profiles in Typic Haploxerepts (TH1) soil type, 4 profiles in Fluvaquentic Endoaquepts (FE) soil type, 6 profiles in Typic Calcixerepts (TC) soil type, 2 profiles in Typic Endoaquepts (TE) soil type, 5 profiles in Fluventic soil type Haploxerepts (FH) and 2 profiles were located in Typic Halaquept (TH2) soil type. At a certain distance from the excavation site of the profiles, four soil samples were taken from four directions of the profile. Using principal component analysis (PCA), among 22 characteristics affecting soil quality (TDS), the minimum characteristics affecting soil quality (MDS) were determined. Then the soil quality in different soil types of region was evaluated using two cumulative soil quality indices (IQI) and Nemuro Quality Index (NQI) and each of them was evaluated in two sets of TDS and MDS in different soil types. 3- Results Among the measured parameters, pH had the lowest (2.5%) and salinity (EC) had the highest coefficient of variation (154.6%) in the region. Among the 22 measured soil properties, sodium absorption ratio (SAR) in the first component, nickel element (Ni) in the second component, cation exchange capacity (CEC) in the third component, sand percentage in the fourth component, active lime (ACCE) in the fifth component and absorbable phosphorus (PAW) in the sixth component were selected as MDS. The examination of the soil quality index showed that the soils of this region mainly have quality grade II (57%). The highest average value of selected soil quality index related to MDS mode in IQI model was calculated with a value of 0.79 in Fluventic Haploxerepts soil type and the lowest average value related to TDS mode in NQI model was calculated with 0.28 value in Typic Halaquepts soil type. The correlation coefficient between the soil quality index with the total category and minimum data in both IQI and NQI models was equal (R2=0.48). 4- Discussion & Conclusions The sequence order of both soil quality indices (IQIa, NQI) in both TDS and MDS conditions in the types of the studied area was as FE>TE>TH1>TC>FH>TH2. Therefore, the highest soil quality was observed in the Fluventic Endoaquepts type and the lowest soil quality was observed in the Typic Halaquepts type. Based on the results, both indicators were classified in three classes (good, medium and poor) in TDS and MDS sets. In the case of TDS, 57.83% of land (equivalent to 19731 hectares) had good class (II), 30.48% of land (equivalent to 10400 hectares) had medium class (III) and 11.69% of land (equivalent to 3990 hectares) <s>they</s> had poor class (IV); (very good (I) and very poor (V) class were not observed). In MDS mode, 18.56% of lands (equivalent to 6333 hectares) had very good class (I), 27.15% of lands (equivalent to 9264 hectares) had good class (II) and 54.29% of lands (equivalent to 18524 hectares) <s>They</s> had medium class (III); (weak class (IV) and very weak (V) were not observed). The degrees of IQIa and NQI indices were similar and were divided into three classes (good, medium and poor). As a result, 39.3% of land (equivalent to 13412 hectares) was in good class (II), 24.59% of land (equivalent to 8392 hectares) was in medium class (III) and 1.36% of land (equivalent to 12317 hectares) was placed in poor class (IV); (very good (I) and very poor (V) classes were not observed). In general, the soils of the region were limited in terms of the studied indicators in the parts leading to the lake, and there was a significant correlation between IQITDS and IQIMDS, and between NQITDS and NQIMDS. This shows that the determined MDS set can be a good representative of TDS in soil quality assessment in Urmia Plain.   تجزیه به مؤلفه اصلی, حداقل مجموعه داده‌ها, شاخص کیفیت تجمعی, شاخص کیفیت نمرو. Principal Component Analysis, Minimum Data Set, Integrated Quality Index, Nemoro Quality Index, Soil Quality 173 193 http://magazine.hormozgan.ac.ir/browse.php?a_code=A-10-940-1&slc_lang=fa&sid=1 Ali barikloo علی باریکلو ali_barikloo@alumni.znu.ac.ir 10031947532846008227 10031947532846008227 No Dept. of Soil Science and Engineering, University of Zanjan, Zanjan, Iran گروه مهندسی علوم خاک، دانشکده کشاورزی، دانشگاه زنجان، زنجان، ایران parisa alamdari پریسا علمداری p_alamdari@znu.ac.ir 10031947532846008228 10031947532846008228 Yes Dept. of Soil Science and Engineering, University of Zanjan, Zanjan, Iran گروه مهندسی علوم خاک، دانشگاه زنجان، زنجان، ایران salar rezapour سالار رضاپور s_rezapour2000@yahoo.com 10031947532846008229 10031947532846008229 No Dept. of Soil Science and Engineering, Urmia University, Urmia, Iran گروه مهندسی علوم خاک، دانشگاه ارومیه، ارومیه، ایران roohollah taghizadeh روح الله تقی زاده مهرجردی taghizadeh130@gmail.com 10031947532846008230 10031947532846008230 No Faculty of Agriculture and Natural Resources, Ardakan University, Yazd, Iran دانشکده کشاورزی و منابع طبیعی، دانشگاه اردکان، یزد، ایران