DOCSLIB.ORG

Micromorphology of Pedogenic Carbonate Features in Soils of Kohgilouye, Southwestern Iran

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Micromorphology of Pedogenic Carbonate Features in Soils of Kohgilouye, Southwestern Iran J. Agr. Sci. Tech. (2012) Vol. 14: 225-239 Micromorphology of Pedogenic Carbonate Features in Soils of Kohgilouye, Southwestern Iran 1 H. R. Owliaie ABSTRACT The micromorphology of pedogenic carbonate features in calcareous soils of arid and semiarid regions of Kohgilouye Province, Southwestern Iran, has been studied to determine their genesis and distribution in different climatic regions. Eight representative pedons (from a total number of 24 pedons) were studied in aridic-ustic (minimum rainfall), ustic and xeric (maximum rainfall) soil moisture regimes. Micromorphological studies indicated that the frequency of secondary calcite as pedogenic nodules, coating or infilling in voids or channels increase from aridic-ustic to xeric soil moisture regimes. The presence of pedogenic calcite coating superimposed on clay coatings in pedons of more humid regions probably suggests a complex history of carbonate leaching, deposition of secondary calcite and clay illuviation. Pendants of calcite were observed in soils with coarser texture in aridic-ustic region as a common pedofeature. Pedogenic nodules in more developed soils of xeric regions were harder containing denser and more contiguous micritic calcite. Degree of impregnation of calcite nodules with Fe/Mn oxides as well as calcite depletion pedofeatures increase in areas with higher rainfall. Needle shaped calcite and cytomorphic calcite were observed in the near surface horizons of the regions with higher rainfall and denser vegetation growth of ustic and xeric soil moisture regimes. Keywords : Arid zone, Calcite, Micromorphology, Soil, Southwestern Iran. INTRODUCTION differences among estimates are a result, at least in part, of the difficulty of differentiating between primary carbonates (lithogenic Arid and semi-arid soils cover over a third of carbonates) and carbonates of secondary origin the world landmasses and are becoming or pedogenic carbonates. The occurrence of increasingly more important worldwide calcitic pedofeatures in calcareous soils of because of increased human populations and southern and southwestern Iran has often been consumption of natural resources (Buol et al., reported in the literature (Khormali et al. , 1997). Calcite is one of the best studied, but 2006; Owliaie et al. , 2006). Downloaded from jast.modares.ac.ir at 8:07 IRST on Saturday October 9th 2021 also one of the most variable pedogenic According to Wright (1987) the type of minerals. It shows a wide variety of shapes pedogenic calcium carbonate is controlled and habits, and occurs as well in arid and mainly by the parent material, climate, and semiarid soils as in temperate and tropical soils vegetation. The formation of pedogenic with restrained drainage (Stoops and Delvigne, carbonates involves complex processes of 1990). dissolution, translocation and precipitation. Secondary or pedogenic carbonates are those Four models have commonly been used to that are formed through the processes describe pedogenic carbonate formation responsible for the soil development. They are namely, the per decensum, per ascensum, in found in relatively dry soils and develop under situ, and biogenic models (Monger, 2002). In natural good drainage and vegetation most micromorphological descriptions, a comprising grass and shrubs mixture. The distinction is made only between _____________________________________________________________________________ 1 Department of Soil Science, Faculty of Agriculture, Yasouj University, Yasouj, Islamic Republic of Iran. e-mail: [email protected] or [email protected] 225 ______________________________________________________________________________ Owliaie microcrystalline (sometimes called micritic), level (a.s.l.) in the southwest to 4,400 m crystalline (sparitic) and acicular calcite a.s.l. in the northeast. The mean annual (Stoops and Delvigne, 1990). Lithogenic precipitation ranges from about 350 mm in carbonate dissolves under ambient moisture southwestern parts to about 1,000 mm in and a relatively high soil CO 2 partial pressure southeastern regions of the Province. 2+ 2+ 2− and the dissolved Ca , Mg and CO 3 ions General data and a location map of the move downward with the percolating soil regions studied are presented in Table 1 and water. As the moisture content decreases, Figure 1. The soil parent material is calcite precipitates (Wang and Anderson, moderately to highly calcareous, although 1998). Development of various pedogenic parent material of southwestern sectors is features, such as channels, cutans, pedotubules dominated by a combination of calcareous and secondary carbonates in soils of arid and gypsiferous materials (pedon 8). Based regions is due to major processes of on previous soil surveys, eight dissolution, leaching and recrystallization representative pedons (from a total number (Chen, 1997). of 24 pedons) with calcic horizons were Pedogenic carbonate has been studied with selected for this investigation in different respect to its importance for plant nutrition, climatic regions of the Province. Soils were carbon sequestration, landscape age, described and classified according to the paleoclimatology, paleoecology, and as a phenomenon per se (Monger, 2002). Soil Survey Manual (Soil Survey Staff, Micromorphological analysis of carbonate 1993) and Keys to Soil Taxonomy (Soil nodules and nodular fabrics in different soil Survey Staff, 2010), respectively. materials shows that their development is a function of several factors: nature of the host MATERIALS AND METHODS matrix (texture, porosity), carbonate and non- carbonate clay distribution, bulk density and the interactions among them (Wiede and Chemical and Physical Analyses Yaalon, 1982). Distinction between pedogenic and Particle-size distribution was determined lithogenic carbonate is of great importance, using sodium hexametaphosphate for the e.g., in soil classification, and has been determination of sand, silt and clay fractions discussed several times in the literature by the pipette method (Day, 1965). (Monger and Gallegos, 2000; Nordt et al., Alkaline-earth carbonate was measured by 2000). acid neutralization (Salinity Laboratory No previous studies have been performed on Staff, 1954). Organic carbon was measured the genesis and micromorphology of the well by wet oxidation with chromic acid and back Downloaded from jast.modares.ac.ir at 8:07 IRST on Saturday October 9th 2021 developed and diverse calcitic pedofeatures in titration with ferrous ammonium sulphate soils of Kohgilouye Province. The main (Nelson, 1982). Determination of the soil pH objective of this study is therefore to was in a saturation paste and electrical investigate the genesis of different calcitic conductivity (EC) in a saturation extract features in the calcareous soils of the different (Salinity Laboratory Staff, 1954). climatic regions of southwestern Iran, using micromorphological studies. Micromorphological Analyses Background of the Studied Area Thin sections with an area about 30 cm 2 were prepared using standard techniques Kohgilouye Province with a land area of (Murphy, 1986). Air-dried oriented clods about 1.6 million ha, is located in were impregnated under vacuum with an southwestern Iran. The elevation of the acetone diluted polyester resin (50/50 ratio), province varies from 300 m above the sea 226 Pedogenic Carbonate Features of Kohgilouye Soils ________________________________ Figure 1. Location map of the study area. and cured for a minimum of one week. Oriented sections were cut with a diamond saw and cemented onto glass microscope slides. The slides were ground and polished to a thickness of 30 µm and described following the guidelines of Stoops (2003). SEM Studies Undisturbed dried samples were mounted on aluminum stubs using double-sided tape and carbon paste, then coated with gold and examined using a Cambridge scanning electron microscope (SEM). Intact soil samples were also observed using a Dino- Lite digital microscope at 60-230X Downloaded from jast.modares.ac.ir at 8:07 IRST on Saturday October 9th 2021 magnification with 1.3M pixel resolution. RESULTS AND DISCUSSION General Results Soil Texture of the studied soils varied from silty loam in pedon 8 to clay in pedons 1, 2 and 4 (Table 2). All soils were calcareous throughout the profile and in most pedons calcium carbonate increased with depth (Table 2). Pedogenic gypsum in pedon 8 occurred as medium to large needle shaped crystals as well as mycelium. The 227 ______________________________________________________________________________ Owliaie Table 2. Some physico -chemical and morphological properties of the pedons studied. a b c Horizon Lower Sand Silt Clay pH OC CCE EC Color depth (%) (%) dSm -1 (moist) (cm) Pedon 1 - Chromic Calcixerert Ap 20 14 42 44 7.8 0.5 11 0.51 10YR4/3 Btss 65 18 29 53 8.0 0.6 18 0.42 10 YR 4/3 Bk 125 22 27 51 8.0 0.7 23 0.48 10 YR 4.5 / 3 Pedon 2 - Calcic Haploxeralf Ap 25 18 38 44 7.5 0.5 29 0.30 7.5 YR 4/4 Btk 1 75 22 26 52 7.4 0.4 38 0.23 7.5 YR 4/4 Btk2 115 20 30 50 7.5 0.4 46 0.27 7.5YR4/4 Btk3 150 28 25 47 7.7 0.2 49 0.38 7.5YR5/4 Pedon 3 - Calcic Argixeroll Ap 25 25 36 39 7.5 1.5 20 0.57 10 YR 3/1 Bt 50 19 32 49 7.7 0.7 24 0.31 7.5YR4/4 Btk 100 40 26 34 7.8 0.2 55 0.24 10YR4/4 Pedon 4 - Calcic Rhodxeralf Ap 25 18 38 44 7.5 0.5 29 0.60 5R4/3 Btk1 75 22 26 52 7.4 0.4 38 0.28 10R3/5 Btk2 115 20 30 50 7.5 0.4 46 0.24 10R3/6 Btk 3 150 28 25 47 7.7 0.2 49 0.21 10 R3/6 Pedon 5 - Calcic Haplustalf Ap 20 30 44 26 7.5 1.4 30 0.53 7.5YR4/4 Btk 1 45 25 36 39 7.6 0.7 32 0.47 10 YR 4/4 Btk 2 100 23 42 35 7.6 0.3 35 0.75 10 YR 4/4 Ck 150 44 36 20 7.5 0.2 79 0.91 7.5YR8/ 1 Pedon 6 - Calcic Haplustept Ap 30 26 46 28 7.4 1.6 42 0.73 10 YR 4/ 4 Bw 55 20 46 34 7.5 1.1 37 0.74 7.5YR4/ 4 Bk 1 95 22 44 34 7.7 0.2 47 0.31 7.5 YR 4/ 4 Bk2 150 22 48 30 7.7 0.1 48 0.30 7.5YR4/ Downloaded from jast.modares.ac.ir at 8:07 IRST on Saturday October 9th 2021 4 Pedon 7 - Typic Calciustept Ap 20 24 52 24 7.4 1.1 55 0.78 10YR4/ 4 Bk 1 65 26 45 29 7.5 0.3 58 0.54 10 YR 4/ 4 Bk 2 90 24 49 27 7.9 0.3 60 0.31 10 YR 4/ overall microstructure of the studied soils (Table 3).
Load more

Recommended publications
  • Assessing Drought Regions and Vulnerability Through Soil Climate Regimes
    Assessing Drought Regions and Vulnerability Through Soil Climate Regimes William J. Waltman University of Nebraska, Lincoln, NE 68583-0915., Stephen Goddard, Gang Gu, Stephen E. Reichenbach, Mark D. Svoboda, and Jeffrey S. Peake. Abstract The agricultural landscapes of the Great Plains reflect a complex pattern of soil climate regimes (Soil Taxonomy, Soil Survey Staff, 1999) and inherent variability that influence the cropping systems and behavior of farmers. The historical crop yields and acreage harvested of crops were compared with climatic events through time to describe the trends and adaptations of farmers and changes in agroecology. The USDA National Agricultural Statistics Service and Risk Management Agency's county-level databases were coupled with soil climate regimes derived from the Enhanced Newhall Simulation Model to explain spatial relationships of crop yields and identifying growing environments favorable to corn, soybeans, sorghum, and wheat. In addition, these geospatial databases can be used to characterize shifts in growing environments through time and space. Comparisons were generated at the county level between irrigated and nonirrigated yields, yield ratios (corn:soybean) to identify favored environments, shifts in crop acreages reflecting past climatic events and changes in genetics, and dominant "cause-of-loss" processes for specific crops. The Enhanced Newhall Simulation Model was used to derive probabilities of soil climate regimes and differentiate agroecological zones. This study also addresses the changes in the agroecology and behavior of soil climate regimes in the Great Plains and connections to El Nino/La Nina events. Introduction Drought is the dominant process of crop loss nationally and within Nebraska. As Table 1 illustrates, on a statewide basis for Nebraska, nearly two-thirds of the 18.6 million harvested acres are covered by crop insurance.
    [Show full text]
  • Keys to Soil Taxonomy
    United States Department of Agriculture Keys to Soil Taxonomy Ninth Edition, 2003 Keys to Soil Taxonomy By Soil Survey Staff United States Department of Agriculture Natural Resources Conservation Service Ninth Edition, 2003 The United States Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at 202-720-2600 (voice and TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326W, Whitten Building, 14th and Independence Avenue, SW, Washington, DC 20250-9410, or call 202-720-5964 (voice and TDD). USDA is an equal opportunity provider and employer. Cover: A natric horizon with columnar structure in a Natrudoll from Argentina. 5 Table of Contents Foreword .................................................................................................................................... 7 Chapter 1: The Soils That We Classify.................................................................................. 9 Chapter 2: Differentiae for Mineral Soils and Organic Soils ............................................... 11 Chapter 3: Horizons and Characteristics Diagnostic for the Higher Categories .................
    [Show full text]
  • Plant-Water Demand Characteristics in the Alfisol, Zaria Nigeria
    Plant-Water demand Characteristics in the Alfisol, Zaria Nigeria Dim, L.A.1 – Odunze, A.C. – Heng, L.K. – Ajuji, S. Centre for Energy Research and Training, Ahmadu Bello University, P M B 1014, Zaria, Nigeria Email: [email protected]; Tel: 08023635501 Corresponding Author’s E-mail: [email protected] Abstract The Nigeria Guinea Savanna zone currently witness increasing intensification of agricultural production activities. The soils are said to have ustic moisture and isohyperthermic temperature regimes implying that rainfalls during the cropping season are limited, irregular or during the dry seasons crop production would be strongly affected by available soil water inadequacy for crop use and production. Supplemental or total water supply by irrigation would therefore be necessary to avert crop failure. Also physical restriction to root elongation can reduce soil water and nutrients uptake as well as plant growth irrespective of water and nutrient supply. This study therefore evaluated soil characteristics and water extraction depth by maize (test crop) in the Northern Guinea Savanna zone Alfisol in Zaria (110 10¹N and 7035¹E) Nigeria. Results show that minimal soil water was extracted by maize at seedling and crop maturity phases, and optimal at crop establishment to grain filling phases. Zone of active soil water extraction shown by the study is 10 to 20 Cm soil depth. Water rather accumulated at the shallow depths of 30 Cm and below following the presence of such sub soil free drainage obstructions as clay and plinthic layers. 1. Introduction Tropical semi-arid regions usually have large variations in physical conditions, both over time (variation in weather among years) and location (climate and edaphic conditions).
    [Show full text]
  • Genesis of Mollisols Under Douglas-Fir
    University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1983 Genesis of Mollisols under Douglas-fir Mark E. Bakeman The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Bakeman, Mark E., "Genesis of Mollisols under Douglas-fir" (1983). Graduate Student Theses, Dissertations, & Professional Papers. 2434. https://scholarworks.umt.edu/etd/2434 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. COPYRIGHT ACT OF 1976 THIS IS AN UNPUBLISHED MANUSCRIPT IN WHICH COPYRIGHT SUB­ SISTS, ANY FURTHER REPRINTING OF ITS CONTENTS MUST BE APPROVED BY THE AUTHOR, MANSFIELD LIBRARY UNIVERSITY OF MONTANA DATE : 19 83 THE GENESIS OF MOLLISOLS UNDER DOUGLAS-FIR by MARK E. BAKEMAN B.S., S.U.N.Y. College of Environmental Science and Forestry, Syracuse, 1978 Presented in partial fulfillment of the requirements for the degree of Master of Science UNIVERSITY OF MONTANA 1983 Approved by: Chairman, B6ard of Examiners rh, Graduate Schoor Date UMI Number: EP34103 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent on the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted.
    [Show full text]
  • Late-Quarternary Stratigraphy, Pedology
    AN ABSTRACT OF THE THESIS OF Dustin White for the degree of Master of Arts in Interdisciplinary Studies in Anthropology, Geology, and Anthropology presented on May 27, 1998. Title: Late-Quaternary Stratigraphy, Pedology and Paleoclimatic Reconstruction of the Cremer Site (24SW264), South-Central Montana: A Geoarchaeological Case Study. Abstract approved: Redacted for Privacy Robson Bonnichsen This study utilizes a multidisciplinary research approach integrating the sciences of archaeology, geology, pedology and paleoclimatology. Deeply stratified and radiocarbon dated sedimentary sequences spanning the last 10,000 yr B.P. are reported for the Cremer site (24SW264), south-central Montana. Previous investigations at the site revealed an archaeological assemblage with Early Plains Archaic through Late Prehistoric period affiliations. Expanded testing of the site integrates the existing cultural record with new data pertaining to Holocene environmental changes at this northwestern Great Plains locality. Detailed pedological descriptions were made along three trenches excavated at the site. The combined soil-stratigraphic record indicates that distinct intervals of relative landscape stability and soil development occurred at the site at ca. 10,000 yr B.P., 7,500 yr B.P. and intermittently throughout the last ca. 6,000 yr B.P. Periods of significant landscape instability (upland erosion and valley deposition) occurred immediately following each of the early Holocene soil forming intervals identified above, and episodically throughout the middle to late Holocene. The impetus for early Holocene environmental instability is attributed to generally increased aridity on the northwestern Great Plains. Comparative analyses of site data with both regional environmental proxy records and numerical models of past climates (General Circulation and Archaeoclimatic models) are made to test the findings from the Cremer site.
    [Show full text]
  • Report III - 3 Agro-Ecology
    WEC-10-2001 Report III - 3 Agro-Ecology 1 WEC-10-2001 Table of Contents 1. Introduction _________________________________________________________________ 4 2. Agricultural Land ____________________________________________________________ 5 2.1 Land Holdings ___________________________________________________________ 5 2.2 Agricultural Regions______________________________________________________ 6 2.3 Available Land __________________________________________________________ 6 2.3.1 Cultivable VS pasture land _____________________________________________ 9 2.3.2 Available cultivable land _______________________________________________ 9 2.3.3 Irrigated areas expansion _______________________________________________ 9 3. Soils ______________________________________________________________________ 12 3.1 Background ____________________________________________________________ 12 3.2 An Overview of Soil Genesis ______________________________________________ 13 3.2.1 Soil forming factors __________________________________________________ 13 3.2.1.1 Climate __________________________________________________________ 13 3.2.1.2 Topography _______________________________________________________ 14 3.2.1.3 Vegetation ________________________________________________________ 14 3.2.1.4 Parent material ____________________________________________________ 14 3.2.1.5 Time ____________________________________________________________ 14 3.2.2 Soil formation processes _______________________________________________ 15 3.3 Brief Description of Soils _________________________________________________
    [Show full text]
  • The Natural Soil Drainage Index: an Ordinal Estimate of Long-Term Soil Wetness
    THE NATURAL SOIL DRAINAGE INDEX: AN ORDINAL ESTIMATE OF LONG-TERM SOIL WETNESS Randall J. Schaetzl Department of Geography 128 Geography Building Michigan State University East Lansing, Michigan 48824-1117 Frank J. Krist, Jr. GIS and Spatial Analysis, Forest Health Technology Enterprise Team USDA Forest Service 2150 Centre Avenue Bldg. A, Suite 331 Fort Collins, Colorado 80525-1891 Kristine Stanley Department of Geography University of Wisconsin Madison, Wisconsin 53706-1491 Christina M. Hupy Department of Geography and Anthropology University of Wisconsin Eau Claire, Wisconsin 54702-4004 Abstract: Many important geomorphic and ecological attributes center on soil water content, especially over long timescales. In this paper we present an ordinally based index, intended to generally reflect the amount of water that a soil supplies to plants under natural conditions, over long timescales. The Natural Soil Drainage Index (DI) ranges from 0 for the driest soils (e.g., those shallow to bedrock in a desert) to 99 (open water). The DI is primarily derived from a soil’s taxonomic subgroup classification, which is a reflection of its long-term wetness. Because the DI assumes that soils in drier climates and with deeper water tables have less plant-useable water, taxonomic indicators such as soil mois- ture regime and natural drainage class figure prominently in the “base” DI formulation. Additional factors that can impact soil water content, quality, and/or availability (e.g., tex- ture), when also reflected in taxonomy, are quantified and added to or subtracted from the base DI to arrive at a final DI value. In GIS applications, map unit slope gradient can be added as an additional variable.
    [Show full text]
  • Application of the Hybrid-Maize Model for Limits to Maize Productivity Analysis in a Semiarid Environment
    300 Liu et al. Hybrid-MaizeScientia model analysis Agricola for maize productivity Application of the Hybrid-Maize model for limits to maize productivity analysis in a semiarid environment Yi Liu1,2, Shenjiao Yang2,3, Shiqing Li2, Fang Chen1* 1Chinese Academy of Sciences/Wuhan Botanical Garden – ABSTRACT: Effects of meteorological variables on crop production can be evaluated using vari- Lab. of Aquatic Botany and Watershed Ecology – 430074 ous models. We have evaluated the ability of the Hybrid-Maize model to simulate growth, de- – Wuhan – China. velopment and grain yield of maize (Zea mays L.) cultivated on the Loess Plateau, China, and 2Chinese Academy of Sciences and Ministry of Water applied it to assess effects of meteorological variations on the performance of maize under Resource/Institute of Soil and Water Conservation – State rain-fed and irrigated conditions. The model was calibrated and evaluated with data obtained Key Lab. of Soil Erosion and Dryland Farming on the Loess from field experiments performed in 2007 and 2008, then applied to yield determinants using Plateau – 712100 – Yangling – China. daily weather data for 2005-2009, in simulations under both rain-fed and irrigated conditions. 3Chinese Academy of Agricultural Sciences/Farmland The model accurately simulated Leaf Area Index , biomass, and soil water data from the field Irrigation Research Institute – 453003 – Xinxiang – China. experiments in both years, with normalized percentage root mean square errors < 25 %. Gr.Y *Corresponding author <[email protected]> and yield components were also accurately simulated, with prediction deviations ranging from -2.3 % to 22.0 % for both years. According to the simulations, the maize potential productivity Edited by: Thomas Kumke averaged 9.7 t ha−1 under rain-fed conditions and 11.53 t ha−1 under irrigated conditions, and the average rain-fed yield was 1.83 t ha−1 less than the average potential yield with irrigation.
    [Show full text]
  • Jarauta-Bragulat, E. (1998)
    PRESENTING, ANALYSING AND COMPARING TWO SOIL MOISTURE REGIME SIMULATION MODELS. APPLICATION TO MOISTURE REGIMES ESTIMATION OF CATALONIA SOILS. Eusebi JARAUTA-BRAGULAT Dept of Applied Mathematics III. Civil Engineering School, Universitat Politècnica de Catalunya. C/. Gran Capità, s/n. Edif. C2. 08034-Barcelona (Spain). E-mail: [email protected] Carme HERVADA-SALA Dept of Physics and Nuclear Engineering. Industrial Engineering School, Universitat Politècnica de Catalunya. C/. Colom, 1. 08222-Terrassa (Spain). E-mail: [email protected] ABSTRACT Two main models have been developped for soil moisture regime simulation. The first one was presented by F.Newhall in 1976; the second one was proposed by E.Jarauta in 1989, modifying important aspects of such model: soil profile modelling, infiltration process simulation, evapotranspiration process simulation and Soil Taxonomy criteria application. In this paper we present and analyse both models, and compare their application to soil moisture regime estimation of Catalonia soils. Results obtained are compared to field data. We also present a discussion of the most important aspects to improve in soil moisture regime modelling. 1. INTRODUCTION Soil surveys rely very heavily on soil classification. The usefulness of a soil survey is a critical component in the way that soil science can be made available to users. However, soil surveys are only valuable if the information they contain can help to solve soil-related problems. Soil surveys often contain information that may appear to be of limited value; alternatively, users may not be able to understand some data included in a soil survey report. The amount of useful information in soil surveys should be increased; this can be done by increasing the total information but also by making more reliable predictions from the data.
    [Show full text]
  • Experimental Micropedology— a Technique for Investigating Soil Carbonate Biogenesis Along a Desert-Grassland-Forest Transect, New Mexico, USA
    Experimental micropedology— A technique for investigating soil carbonate biogenesis along a desert-grassland-forest transect, New Mexico, USA Microedafología experimental—Una técnica para investigar la biogénesis de carbonato en el suelo a lo largo de un transecto desierto-pradera-bosque, New Mexico, USA Micropedologia experimental – Uma técnica para investigar a biogénese dos carbonatos no solo ao AUTHORS longo de um transecto deserto-pastagem-floresta, New Mexico, USA @ 11 Khormali F.@ 1 [email protected] Received: 26.03.2013 Revised: 25.07.2013 Accepted: 28.01.2014 Monger C.2 ABSTRACT Feng Y.2 Manipulative experiments—characterized by comparing treatments to controls—are widespread in scientific investigations. This study uses experimental micropedology to investigate whether soil microbes precipitate carbonate if a liquid growth-medium is applied to soil in situ. This was undertaken using apparatuses designed to (1) obtain micromorphological images of biogenic carbonate on microscope @ Corresponding Author slides, (2) to quantify carbonate formation in fiberglass cloths, and (3) to measure associated carbon- isotope fractionations. The apparatuses were buried and harvested at monthly intervals from December 1 Department of Soil 2010 to June 2011. The study was conducted along an ecological transect in New Mexico, USA, at Sciences, Faculty of three sites: a low-elevation desert (C3 shrubs), an intermediate-elevation steppe (C4 grasses), and a Water and Soil high-elevation forest (C3 conifers). In addition to comparing bioclimatic zones, the effect of parent Engineering. Gorgan University of Agricultural material was also tested using paired limestone and igneous soils at each site. Soil samples in their Sciences and Natural natural state and inserted microscope slides were analyzed with binocular, petrographic, and scanning Resources.
    [Show full text]
  • Soil Moisture and Temperature Regimes in Soil Taxonomy S
    9 duripan. These horizons occur mostly in soils of arid and Co., New York, 1956. and semiarid regions and indicate the depth of water 2. Soil Taxonomy: A Basic System of Soil Classification movement. In soils rich in carbonates, the calcic hori­ for Making and Interpreting Soil Surveys. Soil Con­ zon tends in time to become plugged with carbonates servation Service, U.S. Department of Agriculture, and cemented into a hard, massive, continuous horizon U.S. Government Printing Office, USDA Handbook that is called petrocalcic. In engineering behavior this 436, 1975. horizon simulates hard country rock. 3. L. J. Bartelli and T. A. Weems. Formation and The diagnostic horizons may not have a direct bearing Classification of Soils. Soil Survey of Tensas Parish, on soil behavior, but they are important building blocks Louisiana, U.S. Government Printing Office, 1968, of the system. They are used to group together soils pp. 58-62. that have something in common that is eventually ex­ 4. G. D. Smith. Objectives and Basic Assumptions of pressed in the unique behavior of the soil. For example, the New Classification System. Soil Science, Vol. 96, ai·gillic horizons indicate an accumulation of transported No. 1, July 1963, pp. 6-16. clay; they do not reflect kind and amount of clay, which 5. R. W. Simonson. Lessons From the First Half of · strongly influence engineering behavior. Kind and Soil Survey? I. Classification of Soils. Soil Science, amount of clay aJ'e reflected in the lower categories of Vol. 74, No. 3, Sept. 1952, pp. 240-257. the system, namely, family and series.
    [Show full text]
  • An Examination of Geographic Patterns of Soil Climate and Its Classification in the U.S
    Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations 12-2016 An examination of geographic patterns of soil climate and its classification in the U.S. system of soil taxonomy Hans Edwin Winzeler Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Climate Commons, and the Soil Science Commons Recommended Citation Winzeler, Hans Edwin, "An examination of geographic patterns of soil climate and its classification in the U.S. system of soil taxonomy" (2016). Open Access Dissertations. 1028. https://docs.lib.purdue.edu/open_access_dissertations/1028 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Graduate School Form 30 Updated PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance This is to certify that the thesis/dissertation prepared By Hans Edwin Winzeler Entitled AN EXAMINATION OF GEOGRAPHIC PATTERNS OF SOIL CLIMATE AND ITS CLASSIFICATION IN THE U.S. SYSTEM OF SOIL TAXONOMY For the degree of Doctor of Philosophy Is approved by the final examining committee: Phillip R. Owens Zamir Libohova Co-chair Brad Joern Co-chair Venkatesh Merwade Darrel Schulze To the best of my knowledge and as understood by the student in the Thesis/Dissertation Agreement, Publication Delay, and Certification Disclaimer (Graduate School Form 32), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy of Integrity in Research” and the use of copyright material. Approved by Major Professor(s): Phillip R. Owens and Brad Joern Approved by: Joe M. Anderson 12/7/2016 Head of the Departmental Graduate Program Date i AN EXAMINATION OF GEOGRAPHIC PATTERNS OF SOIL CLIMATE AND ITS CLASSIFICATION IN THE U.S.
    [Show full text]