بررسی برخی عوارض میکروسکوپی در کشت‌‌های طولانی مدت کلزا و چغندرقند

Background and objective: The change of cultivated land and the type of crop and land product could be change the size, shape and connect the holes and looking for it to affect the soil microstructure. The cultivation of Canola and Sugar beet is on the rise because of compatibility in diverse climatic conditions. The purpose of this study is to check events micromorphological characteristics Canola and Sugar beet cultivation under the same climate regime.
Materials and methods: The study area is located in the west southern of Nahavand in Hamadan province. Eight profiles were dug in the study area and soil samples were collected as disturbed and undisturbed. Physical and chemical characteristics analyzed. 17 thin sections of undistributed clods of 12 different horizons were prepared. Micromorphological descriptions were made according to Stoops guidline.
Results: Soil samples were classified to Entisols and Inceptisols orders based on their micro/macro-morphological, physical and chemical characteristics according to key of soil taxonomy. Cation exchange capacity mean in sugar beet culture were achived around 18 and in canola cultivation equal to 35Cmolc/kg. Organic matter return is affected on CEC value. Organic matter content in canola culture more caculated than sugare beet cultivation, too. The micromorphological results showed that micro structures are massive and platy in surface soils horizons while in subsurface horizons were converted to sub-angular blocky and angular blocky to crumb for Sugar beet and Canola, respectively. Microstructures have more developed in Canola rather than Sugar beet cultivation. The results demonstrated that the most voids in thin sections of Canola culture were consisting of channeles and chumber voids with more extending planner voids and in the canola cultivation channels voids more observed than sugare beet culture. Vesicles and Vughs were observed as common voids in Sugar beet cultivation.The distribution pattern in all thin section is predominantly close–open porphyric. The common observed b-fabric in all thin sections was crystallitic form and in some case detected as unspecified. Filling by Fe, Mn, calcite, and plant residues, Fe/Mn and calcite nodules in soil matrix, and also their coatings and hypo-coatings were main pedofeatures in thin sections. Root residues showed more expansion and depth in Canola culture compared to Sugar beet.
Conclusion: Results of physico-chemical properties showed that in general, both plants have had substantial role in soil alteration; but the canola plants have developed soils predominantly. Micromorphology results as a reliable technique in assessing exact soil forming factors by plants confirm this subject.