نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه علوم و مهندسی خاک، دانشکده کشاورزی، دانشکدگان کشاورزی و منابع طبیعی، دانشگاه تهران، کرج، ایران.
2 گروه علوم و مهندسی خاک، دانشکده کشاورزی، دانشکدگان کشاورزی و منابع طبیعی، دانشگاه تهران، کرج-ایران
3 موسسه علوم زمین، بخش علوم خاک، دانشگاه لایبنیتس هانوفر، هانوفر، آلمان
4 گروه مدیریت دولتی، دانشکده مدیریت و اقتصاد، دانشگاه آزاد اسلامی واحد علوم و تحقیقات، تهران، ایران،
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Sandy soils have low productivity due to a lack of organic matter (OC), cation exchange capacity (CEC), and water retention. This study aimed to determine the optimal amounts of humic acid (HA) and carboxymethyl cellulose (CMC) as soil amendments and their effectiveness in improving some physical and chemical properties of sandy soil. A completely randomized experimental design including 10 treatments including control, HA (1, 2, and 3 gkg-1) in combination with CMC at (1, 2, and 5 gkg-1) in three replications was used. After the incubation period (3 months), soil properties including saturated moisture (SP), bulk density (BD), texture, the electrical conductivity of saturated extract (ECe), pH, OC, and CEC were measured. Variance analysis showed that HA and CMC had a significant effect on CEC (4.58-5.31 cmolckg-1), OC (0.28-0.41%), ECe (0.33-0.56 dSm-1), BD (1.31-1.59 gcm-3), and SP (37.76-43.28 %). Considering the results, statistical results, and clustering of experimental treatments, it was determined that the treatment of 2 gkg-1 humic acid combined with 5 gkg-1carboxymethyl cellulose had the most significant impact on soil improvement, such that organic carbon increased by 153%, cation exchange capacity by 52%, and saturation moisture by 8%, while bulk density decreased by 4%. These findings suggest the application of humic acid and carboxymethyl cellulose as an effective method for improving sandy soils in arid and semi-arid regions.
کلیدواژهها [English]
Global food demand is expected to increase by 56% by 2050, while the area of unconstrained land is minimal, and most agricultural land is located in arid and semi-arid regions and faces constraints such as lack of water, nutrients, and organic matter reserves. The main characteristics of soils in arid and semi-arid areas are the predominance of sand, low water holding capacity, low organic matter and cation exchange capacity, and poor nutrient availability for plant growth. A substantial portion of Iran’s low-yield and desert lands (approximately 43 million hectares) consists of sandy soils with low productivity for crop production. One of the methods for improving the physical and chemical conditions of these soils is the addition of organic matter to them. The main objective of this study is to determine the optimal amounts of humic acid and carboxymethyl cellulose as soil amendments and to evaluate their effectiveness in improving some physical and chemical properties of sandy soil.
In this study, a sandy soil located on non-saline wind-blown sediments in Najmabad village, Nazarabad county, Alborz province was sampled. The soil samples were transported to the laboratory, air-dried naturally, and sieved through a 2 mm sieve. Soil treatments included humic acid at three levels (1, 2, and 3 gkg-1 soil) and CMC at three levels (1, 2, and 5 gkg-1 soil). Carboxymethyl cellulose was applied in the form of white sugar granules. The soil treatments were incubated for 12 weeks at a temperature of 25 degrees and a humidity of 80%. The study was conducted using a completely randomized design with 10 treatments and 3 replicates. The experimental data were analyzed using Minitab 16 software, applying statistical methods including Analysis of Variance (ANOVA), Tukey's test, Principal Component Analysis (PCA), and clustering. ANOVA and Tukey's test were used to identify significant differences between treatments, while PCA was employed for dimensionality reduction and pattern recognition. Clustering was utilized to group treatments based on similar characteristics.
After the end of the incubation period, soil properties including saturated moisture content (SP), bulk density (BD), texture, saturated extract electrical conductivity (ECe), pH, organic carbon (OC), and cation exchange capacity (CEC) were measured. The research was conducted with a completely randomized experimental design including 10 treatments in three replications for humic acid and carboxymethyl cellulose and the experimental data were analyzed with Minitab 16 software.
Analysis of variance showed that in general, humic acid and carboxymethyl cellulose treatments had a significant effect on CEC (range of change 4.58 to 5.31 cmol(c)kg-1 soil), OC (range of change 0.28 to 0.41%), ECe (range of change 0.33 to 0.56 dSm-1), BD (range of change 1.31 to 1.59 gcm-3) and SP (range of change 37.66 to 43.28%). Considering the experimental data results, statistical results and clustering of experimental treatments, the application of 2 gkg-1 soil humic acid plus 5 gkg-1 soil carboxymethyl cellulose was selected as the most suitable treatment for the improvement of sandy soils in arid and semi-arid regions. This treatment effectively helped in the improvement of sandy soil by improving the physical and chemical properties of the studied sandy soil, including a sharp increase in OC (by 153%), an increase in CEC (by 52%), a decrease in BD (by 4%) and an increase in SP (by 8%).
Conceptualization; Alireza Raheb and Ahmad Heidari; methodology, Alireza Raheb, Ahmad Heidari, Mostafa Abdollahpour, Hassan Etesami and Hamidreza Mokhtari Esfidvajani; validation, Alireza Raheb and Ahmad Heidari ; formal analysis, Sara Talaee Khosrowshahi and Hadis Khosravian Chatroodi; investigation, Sara Talaee Khosrowshahi; writing-original draft preparation, Sara Talaee Khosrowshahi; writing-Alireza Raheb; visualization, Sara Talaee Khosrowshahi; supervision, Alireza Raheb and Ahmad Heidari; project administration, Alireza Raheb; funding acquisition, Alireza Raheb and Ahmad Heidari. All authors have read and agreed to the published version of the manuscript.” All authors contributed equally to the conceptualization of the article and writing of the original and subsequent drafts.
Data available on request from the authors.
The authors would like to thank Soil Science Department of University of Tehran for providing equipments and Facilities, and Dr. Aida Bakhshi Khorramdareh for her participants of the present study.
The authors avoided data fabrication, falsification, plagiarism, and misconduct.
The author declares no conflict of interest
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