کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6409068 1629478 2014 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Quantitative clay mineralogy of a Vertic Planosol in southwestern Ethiopia: Impact on soil formation hypotheses
ترجمه فارسی عنوان
کانی شناسی کمی از یک پلانوسول ورتیک در جنوب غربی اتیوپی: تاثیر بر فرضیه های تشکیل خاک
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی
Results of a sequential fractionation revealed a strong aggregation of clay particles in the bleached horizon, while the effect of aggregation was far more limited in the vertic horizon. This is believed to be related to the dispersed, impregnative nature of iron oxides in the bleached horizon, compared to the segregated nature of the sharp, nodular concretions found in the vertic horizon. The annealing XRD analysis revealed only minor changes in dehydroxylation temperatures of kaolinites and 2:1 minerals between untreated and DCB-treated samples, indicating that the pretreatment did not significantly alter the mineral lattices. Multi-specimen, full-profile fitting of XRD patterns revealed no large quantitative differences between sub-fractions of the bleached and vertic horizons, although a net increase of 1:1 layers over 2:1 layers towards the top of the profile can be observed in the bleached horizon. This could be interpreted as the result of neo-formation of kaolinite. The main mineralogical differences between the bleached and vertic horizons of the < 2 μm fraction are mainly a result of the different proportions of sub-fractions. Interestingly, the < 0.05 μm fraction seems to be dominated by a complex assemblage of kaolinite and smectite mixed-layer minerals. The obtained detailed view on the mineralogical composition of the clay fraction of a typical Vertic Planosol has provided new insights in the complex nature of these duplex soils, confirming ferrolysis not to be at the origin of the abrupt textural change.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geoderma - Volumes 214–215, February 2014, Pages 184-196
نویسندگان
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