نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 گروه علوم و مهندسی خاک، دانشکده آب و خاک، دانشگاه زابل، زابل، ایران
2 گروه محیط زیست، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objectives: Plant species affect soil properties and soil properties in turn affect those same plant species. However, studies of these effects in wetlands, especially in arid areas under the influence of aeolian processes, have received less attention from researchers. This research was conducted with the aim of studying and determining some physical and chemical characteristics of soil under the dominant plant species in the Hamoun International Wetland including: Tamarix stricta, Cyperus rotundus, Aeluropus lagopoides, Halocnenum strobilaceum, Phragmites communis and comparing them with the control soil.
Materials and Methods: For this purpose, 25 samples of soil from each plant species cover mentioned above and soil without vegetation (control), totaling 150 soil samples, were taken from a depth of 0-20 cm using a supervised random sampling method. Then the soil properties including: soil texture, bulk density, saturated moisture percentage, reaction (pH), electrical conductivity (EC), soluble calcium, magnesium and sodium and sodium adsorption ratio (SAR) were measured and determined using standard methods. The analysis of variance of the data was conducted using a completely randomized design and the comparison of mean data was also performed using the least significant difference test (LSD) using the Statistix 10 software.
Results: The results showed that the soils under the coverage of P. communis species had the highest percentage of clay (16.36%), H. strobilaceum had the highest percentage of silt (84.55%), and T. stricta had the highest percentage of soil sand (84.26%). Despite the differences in the percentages of soil particle sizes of different plant covers and control, the soil texture class of the control (clay loam), A. lagopoides and T. stricta (silt loam), C. rotundus, H. strobilaceum and P. communis (silty clay loam) were determined; indicating a tendency of the textures of soils under plant cover toward coarser textures. Furthermore, the soil under C. rotundus cover had the highest saturated moisture percentage (49.38%) and lowest bulk density (1.49 g cm-3); the soil without vegetation (control) also had the highest amounts of EC (23.07 dS m-3), pH (8.69) and SAR (51.17).
Conclusion: In general, it can be said that the presence of the plant covers studied plays a positive and key role in improving the physical and chemical properties of the soil. The changes in soil particle size were greatly impacted by the dominant wind erosion in the area and occurred in an unusual yet logical manner. Removing the plant cover will cause the process of soil salinization and sodification to occur more rapidly and on a larger scale throughout the Hamoun wetland soils. This is because of the climatic conditions (aridity and strong winds) and geomorphological circumstances (flat lowlands) governing the Hamoun wetlands. Ultimately, this will inevitably lead to the degradation of these soils. Therefore, conserving plant cover in the beds of wetlands located in arid areas is extremely important and necessary to prevent soil degradation and subsequently mitigate the associated environmental consequences.
کلیدواژهها [English]
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