Basaltic Parent Material Research Articles

Black Soils in the Eastern Mediterranean: Genesis and Properties

This study investigates the distribution, morphology, and properties of these soils, focusing on areas such as littoral plains, high hilly areas, and rift depression valleys. Black soils occur in the eastern Mediterranean with a limited distribution, and some of them meet the requirements for black soils according to the INBS (International Network of Black Soils), while others do not. Black soils can be categorized into three types based on their genesis and evolution: calcareous black soils (mainly raw rocky rendzina), hydromorphic black soils, and black soil on basalt. While black soils were found in various bioclimatic stages and parent materials, their presence was notably limited in certain areas, contrary to prior indications. A soil morphology analysis revealed distinct color variations and depths, influenced by the accumulation of organic matter for hydromorphic and calcareous black soils and basaltic parent material for black soils on basalt. A particle size analysis indicated texture variations from clay to loam, with no clear indication of illuviation. A chemical analysis showed alkaline pH levels, except in basalt-derived soils, which exhibited a slight acidity. Hydromorphic black soil is the most important in terms of expansion and agricultural use and is only found in limestone marl deposits and lakes in depressions emerging from Dead Sea rifts under conditions of saturation or poor drainage. These soils have a thick, dark moly horizon and a high organic matter content.

Short‐term phosphorus sorption and desorption in contrasting cropped Vertisols

AbstractVertisols are important cropping soils in tropical and subtropical areas, but in many regions, decades of cropping has substantially reduced concentrations of plant‐available phosphorus (P), especially in the subsoil layers. Phosphorus behaviour in P‐depleted Vertisols has received comparatively little attention, and the availability of P following the addition of inorganic P fertilisers at different concentrations is poorly understood. In this study, we evaluated short‐term P sorption and desorption behaviour in cropped Vertisols in relation to specific soil physical and chemical properties. We collected the surface and subsurface of 15 Australian soils with a broad range of physical and chemical properties, comprising nine Vertisols, three Ferralsols, two Lixisols and one Calcisol. For each soil, we generated sorption and desorption curves (fitted with a Freundlich equation), determined soil physical and chemical properties likely to influence P sorption and evaluated the relationships between the measured soil properties and the Freundlich equation sorption coefficients. The P sorption curves differed drastically between soils, with the sorption equation coefficients (aS × b) significantly correlated with the P buffering index (PBI) and clay content. Clay content itself was correlated with citrate‐extractable Fe and Al oxides and BET surface area. Vertisols formed on basaltic parent materials had greater Fe and Al oxide concentrations, resulting in an overall greater P sorption capacity. Sorption and desorption hysteresis were mostly small. The reacting materials in these soils probably had limited ability to continue to react with P. The Vertisols differed in their capacity to replenish P in the soil solution by desorbing different proportions of previously sorbed P, although the proportion of desorbable P generally increased with greater concentrations of sorbed P. These results suggest that for fertiliser management in these soils, smaller volumes of P enrichment combined with higher P concentrations may result in a greater P recovery by the crop.

Soil evolution in basaltic parent materials under successive climate changes, Saudi Arabia

This study was designed to investigate the successive effects of the early Pleistocene subhumid and early to middle Holocene semi-arid paleoclimates and late Holocene to present day arid/hyperarid conditions on pedogenesis and evolution in Harrat Ithnayn volcano in the Arabian Shield, Saudi Arabia. The investigations were conducted using pedological macro and micro-features, physicochemical characteristics, elemental geochemistry, weathering indices and mineralogical analyses for light and heavy sand and clay fractions. The targeted soils developed in a subhumid paleoclimate and are classified as vitric Andisols, which are little to moderately weathered. Subhumid climate effects were evident through the presence of pedogenic Fe (crystalline oxides, Fed = 25 to 58 g kg─1), fairly high Feo/Fed (0.24 to 0.87), and the predominance of hydroxy-Al smectite and kaolinite. Residual primary minerals and modern arid conditions simultaneously led to accumulation of secondary salts and carbonates. Exchangeable Ca and Mg pools contributed 21–56 % of total Ca and Mg contents, while exchangeable K contributed only up to 4 %. Soil processes thus involved andisolization, salinization, and calcification. These processes were due to successive moist paleoclimates and the current arid conditions, thus revealing their formation under multiple climates.

Digital soil mapping of key secondary soil properties using pedotransfer functions and Indian legacy soil data

Water and nutrient holding capacities are primarily controlled by the secondary soil parameters of water retention characteristics and cation exchange capacities (CEC). Complete suite of these secondary soil parameters is rarely included in legacy soil databases generated in soil survey and mapping efforts. Therefore, pedotransfer functions (PTF) are generally used to derive these parameters. We used PTFs and laboratory-measured water contents at field capacity (θFC) and wilting points (θPWP) and CEC values to augment the existing Indian soil legacy database that contained CEC data for 1681 locations and θFC and θPWP data for about a 3rd of these locations across the country. A quantile regression forest (QRF) algorithm was used to map these three soil parameters at six GlobalSoilMap-specified soil depths. Estimated coefficient of determination (R2) values in the 10-fold cross-validated datasets ranged from 0.60 to 0.65 for CEC while a substantially lower accuracies were found for the water holding capacities (R2 for θFC: 0.27–0.34 and R2 for θPWP: 0.33–0.37). Resulting soil function maps show distinct spatial patterns: high values for the water and nutrient holding parameters in soils developed from basaltic parent materials of central and part of peninsular India and low values in soils developed in the deserts of Western Plains and in soils developed from granite-gneiss parent material commonly seen in many eastern Indian region. Terrain attribute showed stronger influence on the distribution of these secondary soil parameters than the climatic parameters. Specifically, valley depth showed strongest negative correlation coefficients (r: −0.68 to −0.73) with layer-wise CEC values; January temperature showed strongest influence on water holding capacities (r: 0.08 to 0.62 with θFC and 0.14 to 0.62 for θPWP). Thus, CEC in Indian soils is primarily driven by the pedogenesis of clays in which monsoon rain favors clay translocation to deeper soil layers followed by subsequent deposition in subsurface horizons during the post-monsoon dry weathers. Similarly, strong linkages between January temperature and water holding capacities reaffirm the conclusion that temperature of driest quarters is a key driver of water relationships in soil.

The Investigation of Ultic Horizon on Andisols Derived from the Eruption of Mount Tilu (Pleistocene, Basaltic) in West Java, Indonesia

DOI:10.17014/ijog.9.2.159-172Ultic is the soil characteristics in soil taxonomy when argillic or kandic horizon is found within the depth of 125 cm with the base saturation of less than 35 % on the overall of upper 50 cm. The purpose of this research is to investigate whether ultic horizon was found in the soil developing from the Pleistocene eruption of Mount Tilu (basaltic parent materials), in West Java, Indonesia. The method used was descriptive and comparative surveys of three profiles in the area around Mount Tilu, including the investigation of andic soil properties and the formation of argillic or kandic horizon. The result showed that the soils fulfilled the requirements of andic soil properties to be classified as Andisols. Soil never dried for ninety days cumulative (udic) to be classified as Udands. There were Fulvudands and Hapludands in this location. Accumulation of clays was more than 1.2% higher than the overlying horizon found at the depth of 90, 79, and 51 cm in those three profiles. Base saturation in upper 50 cm ranged from 1.07 to 6.86 cmol kg-1 or less than 35 %, making the soils were classified as Ultic Fulvudands and Ultic Hapludands. The high rainfall in the tropics and Pleistocene age led to the leaching of clays for a long period to form the argillic horizon. The influence of rain was stronger than the basaltic parent materials in forming Ultic Hapludands. Basaltic parent material was not strong enough to produce base saturation of more than 35 %.

Ophiolite derived material as parent rocks for Late Jurassic bauxite: evidence for Tithonian unroofing in the Northern Calcareous Alps (Eastern Alps, Austria)

In shallow-water limestones of the Plassen Formation in the Tirolic nappe of the Northern Calcareous Alps, bauxite was formed on karstified and tilted platform margin grainstones to boundstones around the ?Kimmeridgian/Tithonian boundary, or in the Early Tithonian as proven by Protopeneroplis striata Weynschenk, Labyrinthina mirabilis Weynschenk, and Salpingoporella pygmaea Gümbel. The platform established on top of the obducted ophiolite nappe stack. The onset of unroofing at the Kimmeridgian/Tithonian boundary exposed ophiolites to weathering, forming laterites, and bauxites. The weathered ophiolitic material was shed on the tilted, emerged, and karstified platform, where the bauxite accumulated. Continued subsidence led to flooding, and a Tithonian transgressive carbonate sequence sealed the bauxites. XRD analysis of the bauxite yields a composition of mainly boehmite with hematite and some berthierine, kaolinite, and chromite. SEM analysis verified magnetite, hematite, rutile, chromite, zircon, ferropseudobrookite, ilmenite, monazite, xenotime, and garnet distributed in pisoids and within the matrix. The pisoids reach a millimeter in size and partly show cores of older, larger pisoids. The composition of the chromites indicates an ophiolitic origin. Geochemical examination using major- and trace elements points to a mafic andesitic to basaltic parent material contaminated with highly fractionated rocks from an island arc. Formation of Early Tithonian bauxites in shallow-water limestones confirms Middle to Early Late Jurassic ophiolite obduction. This was followed by uplift and unroofing of the orogen from the Kimmeridgian/Tithonian boundary onwards after a period of relative tectonic quiescence with an onset of carbonate platforms during the Kimmeridgian on top of the nappe stack and the obducted Neo-Tethys ophiolites.

Lithological and Topographic Impact on Soil Nutrient Distributions in Tectonic Landscapes: Implications for Pleistocene Human-Landscape Interactions in the Southern Kenya Rift

Tectonically active regions are characterized by complex landscapes comprising soils with heterogeneous physicochemical properties. Spatial variability of nutrient sources enhances landscape biodiversity and creates heterogeneous habitats potentially attractive for animals and humans. In this study, we analyze the role of geological processes in the distributions of soil nutrients in the southern Kenya Rift, a key region in the interpretation of early human-landscape interactions. Our aim is to determine how spatial variations in rock chemistry, as well as topographic gradients and localized zones of rock fracturing from tectonic faulting determine the distributions of plant-available soil nutrients in soils. We hypothesize that present-day soil nutrient levels reflect the long-term chemical and geomorphological characteristics of the landscape and underlying parent material, and that regions with high nutrient availability occur along pathways correlating with locations of hominin fossil sites. Analyses of 91 topsoil samples from the main geological units show that Calcium (Ca) deficiencies predominately occur in shallow soils developed on trachytic volcanic rocks and granitic gneisses, while high Ca levels are associated with basaltic parent material and sedimentary deposits of mixed sources. XRF analysis of rock samples confirms that CaO levels in trachyte rocks are significantly lower than those in basalts, and Ca mobilization in basalt is more effective than in trachyte. Along two toposequences in densely faulted basaltic and trachytic rocks, we observed slope dependent soil nutritional gradients and a systematic increase of the concentrations of Ca, Mg and SOC in topsoils of colluvial sediments downslope of active normal faults. Known hominin sites in the region are located either along corridors of long-term Ca availability or at short-term nutrient hotspots potentially related to active CO2 degassing along active fault zones. This implies a strategic advantage of Ca-rich regions for hominin subsistence strategies, such as provision of predictable constraints on the distribution and mobility of grazing animals in complex tectonic landscapes. Our study implies that geological processes impact nutrient distributions in the southern Kenya Rift. Results of this study have further implications for understanding the role of soils in the interpretation of hominin-landscape interactions in the early stages of human evolution.

Assessment of Biogeochemical–Mineralogical Characteristic and Weathering Indices of Soils Developed on Basaltic Parent Material and Toposequence Under Subhumid Ecosystem

Especially in local areas, the formation of different soils on the same parent material is closely related to the topographic position, which has an important effect on the morphological, mineralogical, biological, and weathering processes of soils. Because, topography affects the distancing of water and other materials from the soil or addition of soil. Besides mineralogical and geochemical events occurring due to topographic change in soils with different development levels on basalt parent material under semitemperate ecological conditions, the purpose of this study is to examine the changes in the biological properties of soils with microbial biodiversity that affect these changes. For this purpose, six soil profiles representing high land plateau, high land back slope, low land plateau, low land back slope, toe slope, and foot slope were examined, which show distribution on the section in the South–North direction on basalt parent material of Engiz Çayı Basin, Turkey. Since soils formed on high slope land have poor profile development, they are described as young soils and classified in the Entisolls, and others are classified in Inceptisol and Vertisolls according to their horizon developments. pH values of surface horizons of all profiles range between 6.74 and 8.28, while organic matter values range from 1.54 to 3.53%. Although the dominant clay mineral is Smectite especially in surface soils, kaolinite clay mineral is also available in Entisol soils. Soil weathering rates are generally between very little weathering and moderate weathering, and Base/R2O3 values are determined between 0.5 and 1.3. Besides, it was determined that fungi has the most diversity among microorganisms of soil formed on basalt and actinobacterium varieties have the most diversity according to bacillus groups. Moreover, in this study, it has been determined that the isolated Actinobacteria members have gene regions that synthesize molecules called siderophores. This case has also been proposed as evidence that Actinobacteria members contribute to soil formation processes.

GPS Based Soil Profile Study in Respect to Morphological and Nutrient Analysis in Pedon of Ganjam District

GPS based two pedons- one each from up and medium land during dry season, studied in the field & analysis done in the laboratory. The difference in properties between two pedons was mostly due to lateritic and basaltic parent material in pedons. The morphology of mineral soils explains the evolution that occurs in the soil body during the process of soil formation, which is predominantly influenced by the parent material and climate. Determination of epipedon and endopedon of diagnostic horizons through description and interpretation of soil profile properties is the basis of land classification, as the knowledge of soil properties, capabilities, and utilization. The results of the study found that, based on its morphological and chemical characteristics, the soil in pedon 1 had brighter colors, higher micronutrient availability, and a thicker horizon compared to the soil in pedon 2. Meanwhile, the pedon 1 is light texture, crumb structure and pedon 2 is heavy texture and sub angular blocky structure. Both the form of density in two pedons was increasing downwards & the value were of a typical mineral soils, but the pore space showed a reverse trend on confirming the compactness and aging of soils towards subsurface horizons. Same results tendency found in micronutrients analysis where pedon 1 rich in micronutrients as compare to pedon 2.

Distribution patterns and sources of heavy metals in soils from an industry undeveloped city in Southern China

The accumulations of heavy metals in urban soils are derived from natural parent materials and complex anthropogenic emission sources. This paper investigated metal contamination in urban soils at an industry undeveloped city (Haikou) in southern China, an ideal place to quantitatively assess the contribution of metals from different sources. The concentrations of most heavy metals in the urban soils of Haikou were much lower than their guideline values and that of those from other big cities in China. In contrast, the chemical speciation of metals in this study was similar to those from other cities. The spatial distributions of heavy metals and principal component analysis (PCA) revealed that basaltic parent materials, traffic emissions, and coal combustion were the main factors controlling the distribution of metals in the soils. The Pb isotope signatures of the Haikou soils were greatly different from those of the Beijing and Shanghai soils, but similar to those of the Guangzhou soils, suggesting the common sources of Pb in southern China cities. The results of ternary mixing model of Pb isotopes showed that the contributions of Pb from natural background, coal combustion and traffic emission sources were 5.3–82.4% (mean: 39.7 ± 21.1%), 0–85.7% (mean: 25.5 ± 24.6%), and 1.9–64% (mean: 34.8 ± 22.9%), respectively. This suggests that traffic emission is still the most important anthropogenic source of Pb in Haikou.

Transfer processes of potential toxic elements (PTE) between rock-soil systems and soil risk evaluation in the Baoshan area, Yunnan Province, Southwest China

Geochemical fluxes in rock-soil systems are important tools in the evaluation of soil environmental risk, especially where the geological background (parent materials) are enriched in potential toxic elements (PTE). In the Baoshan area, the presence of mineral resources along with carbonate and basalt parent materials often leads to PTE being elevated in soils. In this study, we compared rock and soil geochemical compositions by collecting rock samples from the host formations and ore samples from two mineral deposits (Cu–Pb–Zn and Fe–Cu–Pb–Zn) and their overlying soils. This research demonstrates enrichment of PTE (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in soils relative to their parent materials. The enrichment in soils may be due to the removal of mobile elements (e.g., Ca, Na, Mg, and Sr), and coprecipitation (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) and/or adsorption by Fe-oxy-hydroxides (Cr and Ni) under the influence of high pH values during soil formation. The results point to a parent lithological origin and natural enrichment of PTE in Baoshan soils. However, anthropogenic contamination of soils near mining areas is also possible. Soils forming from carbonate rocks, basalts, and especially from mineralized formations have higher PTE concentrations, and in places, levels can exceed the risk screening values for soil contamination of agricultural land of China. Where the latter is the case, it is suggested that ecological monitoring be implemented in the study area. The conventional use of the geo-accumulation index (Igeo) and enrichment factor (EF) methods is challenged in this research and found to underestimate the PTE contamination. A compositional data analysis approach (using clr biplots) is presented which shows that comparison with regional-scale background datasets is essential to provide a more informative approach to evaluate the risk of soil contamination, especially in regions with elevated levels of PTE in parent materials.

Investigation of the clay minerals composition of soils derived from basalt parent materials in the Early Miocene to Early Pleistocene on the Arabian Shield using multiple techniques: implications for paleoclimatic conditions

Knowledge of clay minerals composition can be used to understand paleoenvironmental and/or paleoclimatic conditions, particularly for soils derived from volcanic parent materials that were subjected to diverse climatic conditions during pedogenesis. In this study, the clay minerals composition in soils developed from basaltic parent materials during the Cenozoic (mostly during the Early Miocene to Early Pleistocene) in the harrats region of the Arabian Shield in Saudi Arabia were investigated. Forty-seven clay samples were examined using selective dissolution analyses, X-ray diffraction (XRD), thermogravimetric analysis (TG), Fourier-transform infrared spectroscopy (ATR/FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to obtain a better understanding of the clay minerals developed in basaltic parent materials, particularly under a dry-hot environment. The XRD results revealed that the clay mineralogy was dominated by smectite, kaolin (kaolinite/halloysite), and interstratified vermiculite–chlorite (Vm–Ch), with mica, pseudo-chlorite, palygorskite, and Ca–zeolites as minor components. The TEM provided strong evidence for the presence of allophane and imogolite, which is in line with numerous previous studies on soils formed from basaltic parent materials. The existence of poorly-crystalline minerals in these soils was strongly supported by the selective dissolution analysis results. The combined influence of paleoclimates and parent material is evidenced in the clay minerals in the studied soils. The formation of smectite, Vm–Ch, and chlorite minerals in the harrats soils could be attributed to the simultaneous effect of temperate paleoclimates that dominated the Pliocene and the wet transition periods that occurred through the Pleistocene into the mid-Holocene, while the minor palygorskite and Ca–zeolites could be related to the dry conditions that started in the late-Holocene and persist to the present day. Additional studies regarding the clay mineral assemblages in similar geoenvironmental settings are highly recommend and should account for paleoclimatic conditions to provide a better understanding of the relationship between clay minerals and paleoclimates.

New Soil, Old Plants, and Ubiquitous Microbes: Evaluating the Potential of Incipient Basaltic Soil to Support Native Plant Growth and Influence Belowground Soil Microbial Community Composition

The plant–microbe–soil nexus is critical in maintaining biogeochemical balance of the biosphere. However, soil loss and land degradation are occurring at alarmingly high rates, with soil loss exceeding soil formation rates. This necessitates evaluating marginal soils for their capacity to support and sustain plant growth. In a greenhouse study, we evaluated the capacity of marginal incipient basaltic parent material to support native plant growth and the associated variation in soil microbial community dynamics. Three plant species, native to the Southwestern Arizona-Sonora region, were tested with three soil treatments, including basaltic parent material, parent material amended with 20% compost, and potting soil. The parent material with and without compost supported 15%, 40%, and 70% germination of Common Bean (Phaseolus vulgaris L. ‘Tarahumara Norteño’), Mesquite (Prosopis pubescens Benth), and Panic Grass (Panicum Sonorum Beal), respectively, though germination was lower than in the potting soil. Plant growth was also sustained over the 30 day period, with plants in parent material (with and without amendment) reaching 50% height compared to those in the potting soil. A 16S rRNA gene amplicon sequencing approach showed Proteobacteria to be the most abundant phyla in both parent material and potting soil, followed by Actinobacteria. The potting soil showed Gammaproteobacteria (19.6%) to be the second most abundant class, but its abundance was reduced in the soil + plants treatment (5.6%–9.6%). Within the basalt soil type, Alphaproteobacteria (42.7%) and Actinobacteria (16.3%) had a higher abundance in the evaluated bean plant species. Microbial community composition had strong correlations with soil characteristics, but not plant attributes within a given soil material. Predictive functional potential capacity of the communities revealed chemoheterotrophy as the most abundant metabolism within the parent material, while photoheterotrophy and anoxygenic photoautotrophy were prevalent in the potting soil. These results show that marginal incipient basaltic soil, both with and without compost amendments, can support native plant species growth, and non-linear associations may exist between plant–marginal soil–microbial interactions.

A regional soil and river sediment geochemical study in Baoshan area, Yunnan province, southwest China

This study aims to better understand, at a regional scale, the concentration and distribution of selected chemical elements in surface environments and the influence of natural factors (geological background, geomorphology) and anthropogenic factors (mining activities, land-use, agricultural fertilization) on their distribution in the Baoshan area, Yunnan province, southwest China. Mineral resources (such as copper, lead, zinc, mercury, gold, silver) and carbonate and basalt parent materials in this area often lead to elevated potentially toxic metals (PTMs), which are widely distributed where mining activities have rapidly developed since last 20–30 years. This study makes use of 1574 surface soil data and 425 deep soil data from the National Geochemistry Survey of Land Quality project (NGSLQ), and 1585 archived river sediment data which were collected and analyzed for the Regional Geochemistry-National Reconnaissance program (RGNR). These data, once log-ratio (clr) transformed have been studied by compositional data analysis (CoDA), principle components analysis (PCA) and spatial analysis. In the Baoshan area, the concentration of elements As, B, (Br), Co, Cr, Cu, Hg, (I), Mn, (N), Ni, Sb, (Sc), (Se), V, Fe2O3Total and (COrgonic) are enriched compared to the China Soil Geochemical Baselines program (CGB) and RGNR data sets; while elements Sr and Na2O are depleted compared to CGB and RGNR data sets. Influencing factors on surface soil, deep soil and river sediment composition of the study area are revealed. The distribution of most elements in surface soil, deep soil and river sediment are influenced by natural factors such that: Co, Cr, Cu, Ni, Sc, Ti, V, Fe2O3Total and MgO are controlled by the distribution of basic igneous rocks; Ca, Mg, Sr and pH are controlled by the distribution of carbonate rocks and basic igneous rocks; As, Hg, Sb, (Ag), Cd, Pb and Zn are controlled by mineralization; and other elements normally controlled by the distribution of clastic rocks and acid-intermediate rocks; while the organic matter such as Br, N, (P), S, COrgonic and CTotal in soil data set are controlled by geomorphic (altitude and temperature). Anthropogenic factors are also recognized in the soil data set. For example: high pH values in paddy land and grassland, and low pH values in forested land, garden plot and dry cultivated land; in agricultural area fertilization has caused enrichment of the nutrient elements (COrgonic, CTotal, N, P, etc.,) in surface soil; while in areas of mining, surface soils are contaminated by PTMs (incl. Hg, As, Sb, Cu, Pb, Zn and Cd).

Nonomuraea basaltis sp. nov., a siderophore-producing actinobacteria isolated from surface soil of basaltic parent material.

A Gram-stain-positive, aerobic, spore-forming actinobacterial strain, designated 160415T, was isolated from a surface soil sample, which was formed on basaltic parent material, collected from Samsun, Turkey. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 160415T clustered closely with species of the genus Nonomuraea, and showed the highest sequence similarity to Nonomuraea zeae NEAU-ND5T, Nonomuraea candida HMC10T and Nonomuraea turkmeniaca DSM 43926T with 99.1%, 98.9% and 98.7%, respectively. Chemotaxonomic properties including major menaquinones, diaminopimelic acid, sugar and phospholipid profiles also confirmed the affiliation of the strain to the genus Nonomuraea. The DNA G+C content of strain 160415T was 69.6mol%. DNA-DNA hybridization and average nucleotide identity values between the strain and closely related type strains were less than the recommended cut-off values. On the basis of phylogenetic relationships, genotypic and phenotypic characterizations, strain 160415T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea basaltis sp. nov. is proposed. The type strain is 160415T (= KCTC 39875T = DSM 104309T).

Influence of Toposequence on Physical and Mineralogical Properties of Soils Developed on Basaltic Parent Material under Sub-humid Terrestrial Ecosystem

Understanding of soil forming factors is crucial to define physical, mineralogical and morphological properties of soils. In addition to that soil formations were highly associated with slope positions which have influence on pedogenetic and weathering process of the soils. Because, topography or relief affects how water and other material are added to and removed from soils. The aim of this study is to enhance our understanding of the role toposequence in controlling chemical weathering, influence on physical and mineralogical properties in soils developed on basaltic parent material under sub-humid terrestrial ecosystem in Black Sea region of Turkey using geochemical and mineralogical data obtained from X-ray diffraction and Scanning Electron Microscope analysis. For this purpose, four representative profiles formed on different topographic positions of transect were investigated and designated according to Soil Survey Staff (2014)/IUSS Working Group WRB (2015) classification systems. The results clearly showed that topography strongly affects soil physical, mineralogical and morphological characteristics either directly or indirectly in the local region even soils formed on the same parent material with the same climatic condition. This case was also explained with chemical weathering indices (Chemical Index of Alteration and Chemical Index of Weathering) in this study.

Pedogenic Forms of Iron in Soils Developed from Four Parent Materials

Information on the distribution of various forms of iron in soils are valuable in the study of soil genesis. The objective of this study was to to evaluate the pedogenic forms of iron in soils developed over basement complex and basaltic parent materials of the study area. Geologic units considered in the basement complex area were granite gneiss, biotite granite and migmatite. Stratified random sampling formed the basis for field work. Soil sampling was carried out by digging at least two soil profile pits in each geologic unit. Organically bound, amourphous and total iron oxides were estimated using 0.1 M sodium pyrophosphate, acidified (pH 3) ammonium oxalate, and dithionite-citrate-bicarbonate method, respectively. The total Fe in the soil samples were determined after a mixed acid digestion. In general, total iron fractions were statistically similar among the soils of basement complex geologic units but significantly lower than those of soils derived from basaltic rocks. However, the distribution of iron oxide fractions was similar among the basement and basaltic geologic units. Furthermore, there were significant differences in the distribution of iron oxides in the B horizons of basement complex derived soils. Consequently, the quantity of iron oxides in the B horizon was in the order migmatite > biotite granite > granite gneiss. About 70% of total iron oxides in the soils over granite gneiss, biotite granite and basaltic rocks was amorphous in nature. Furthermore, total iron oxides constitute less than 20% of total clay both in the basement complex and basaltic soils.

Variability of some soil properties along a toposequence in a basaltic parent material of Vom, Plateau State Nigeria

Topography influences the distribution of some soil physical and chemical properties. This study assessed some variation in soil properties resulting from the topographic effect on Basaltic parent material at Vom Jos Plateau State in the Southern Guinea zone of Nigeria. Soil samples were collected at an interval of 20m and at depths of 0 to15cm and 15 to 30cm, parceled, labeled and taken to the laboratory for analysis of the selected for analysis. The results from the study revealed that variations in soil properties along the landscape segments were probably due to their positions toposequence characteristics in soils. Clay, silt and gravel contents varied moderately (CV = 22.9, 15.42 and 32.55% respectively), while sand did not vary much (CV = 8.47%). Organic carbon showed high variability (CV = 38.08%) while soil pH in (H2O and CaCl2) showed less spatial variability (with CV = 4.91 and 6.45% respectively). Available phosphorus has high variability (CV = 37.59%). Magnesium, K and Ca showed high spatial variability (CV = 42.60, 35.85, and 35.84% respectively), while Na and exchange acidity were moderately variable (CV = 24.39 and 24.27% respectively). Generally, some of the soil chemical properties were varied with topographic positions.

Characterization, classification and evaluation of soils of Kamrej Taluka in Surat district, Gujarat for sustainable land use planning

Detailed soil survey was conducted at 1:10,000 scale in the Kamrej taluka of Surat district, Gujarat for characterization, classification and evaluation of the land resources. Two landforms were demarcated in the area viz. lower and upper alluvial plains. Based on morphological, physical and chemical characterization, three soils series (Abrama, Digas and Sampura) were identified. Soils were developed from the basaltic alluvium parent material. The soils were very deep, slightly to moderately alkaline (pH 7.4 to 8.5), non-saline with low to medium in organic carbon (0.15 to 0.66%), low to high in calcium carbonate content (1.9 to 18.6%), medium to high CEC [40.2 to 63.6.0 cmol(p+)kg-1] and high base saturation (75 to 98%). The clay content of the soils varied from 37.4 to 52.8 per cent in surface horizons whereas it varied from 24.8 to 61.1 per cent in sub-surface horizons. Silt and sand content ranged from 12.7 to 39.5 and 16.8 to 54.8 per cent, respectively. The Abrama, Digas and Sampura soils were classified as fine, smectitic (calcareous) hyperthermic Typic Haplusterts; fine, mixed hyperthermic Vertic Haplustepts and fine loamy, mixed (calcareous) hyperthermic Typic Haplustepts, respectively. The area coverage of Abrama soils was 55.7 per cent, followed by Digas (19.7%) and Sampura (11.3%) soils. Soils were assessed as highly to marginally suitable for major crops (sugarcane, rice, wheat, banana and mango). The soil survey datasets can be extended to integrate biophysical data with socio-economic knowledge for sustainable land use planning in Kamrej taluka.

Tracking textural, mineralogical and geochemical signatures in soils developed from basalt-derived materials covered with loess sediments (SW Poland)

This study investigates the scale of inheritance of signatures typical of loess- and basalt-derived substrates in soils having both components present as parent material due to past periglacial processes. Based on field description, particle size distribution, mineralogy (heavy minerals and clay minerals) as well as geochemistry we track the signal of both materials (local basalt-derived and loess-derived), estimate the maximum thickness of loess mantles and mixed zones (having both loess and basaltic components), and note the presence or absence of basal layers without allochtonous additions. The results show that geochemistry and heavy minerals are the most reliable proxies for a verification of aeolian silt contributions and to define individual layers in complex soil parent materials.Soil formation in the studied landscape depends on the type of slope sediments. Typical fine-grained weathering of basalt without input from aeolian silt would promote rather vertic development. However, in thick loess deposits as well as in thin silt-textured materials superimposed on clay loam beds, clay illuviation dominates. Development of argic horizons, however, results in decreasing permeability, promoting water stagnation and enhanced degradation processes in clay-rich subsoil. Instead of Luvisols, Stagnosols and Retisols developed in the study regions. Basaltic block covers mixed with loess host cambic horizons. Based on our findings it seems that at the edge of thin loess deposits no soils exist that developed exclusively from basaltic parent materials.