Sombric-like horizon and xanthization in polychrome subtropical soils from Southern Brazil: implications for soil classification
نویسندگان
چکیده
The occurrence of dark subsurface horizons rich in organic matter (OM) associated with polychrome the B horizon (yellowish over reddish hue) is common soils from Southern Brazil. formation these and combination such morphological attributes has not been properly documented, neither cause effect relationship. Four soil profiles sombric-like a yellowish color at upper part red subsoil were studied Results micromorphology, extractable sesquioxide minerals, clay mineralogy isomorphic substitution Fe by Al iron minerals showed that melanization, xanthization, bioturbation, moderate shrinking/swelling ferralitization most evident pedogenetic processes role. Xanthization closely related to formation. In area findings demonstrated no OM illuviation had taken place. Therefore, classification was revisited, so as take into account underlie their genesis emphasis on aggregation. results suggest sombric may need redefinition, unless can be found which and/or proven.
منابع مشابه
rock magnetic characterisation of tropical soils from southern india: implications to pedogenesis and soil erosion
in this study we report the rock magnetic properties of surface soil samples and their spatialvariability from the northernmost district of kerala to understand pedogenic processes and soil erosion. themagnetic signal is mainly from fine grained pedogenic magnetite as other sources like anthropogenic andlithogenic magnetite, bacterial magnetite and greigite are absent. the surface soil samples ...
متن کاملStable isotope study of cave percolation waters in subtropical Brazil: Implications for paleoclimate inferences from speleothems
We analyze the interannual monthly variability of oxygen isotope ratios in data from IAEA stations along the Atlantic coast of South America between 238 and 348 S to evaluate the influence of parameters such as temperature, rainfall amount and moisture source contribution on meteoric water recharging two karst systems in subtropical Brazil. In addition, a 2 year monitoring program performed on ...
متن کاملOccurrence of sombric-like subsurface A horizons in some andic soils of the Nilgiri Hills (Southern India) and their palaeoecological significance
متن کامل
Particle-size fractions-dependent extracellular enzyme activity in sediments and implications for resource allocation in a subtropical mangrove ecosystem
The distribution of extracellular enzyme activities in particle-size fractions of sediments was investigated in a subtropical mangrove ecosystem. Five enzymes involved in carbon (C), nitrogen (N), and phosphorus (P) cycling were analyzed in the sand, silt, and clay of sediments. Among these fractions, the highest activities of phenol oxidase (PHO), β-D glucosidase (GLU), and N-acetyl-glucosimin...
متن کاملChemical Characterization and Infrared Spectroscopy of Soil Organic Matter from Two Southern Brazilian Soils(1)
Soil organic matter from the surface horizon of two Brazilian soils (a Latosol and a Chernosol), in bulk samples (in situ SOM) and in HF-treated samples (SOM), was characterized by elemental analyses, diffuse reflectance (DRIFT) and transmission Fourier transform infrared spectroscopy (T-FTIR). Humic acids (HA), fulvic acids (FA) and humin (HU) isolated from the SOM were characterized additiona...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Scientia Agricola
سال: 2021
ISSN: ['1678-992X', '0103-9016']
DOI: https://doi.org/10.1590/1678-992x-2019-0115