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1
J.J. Al-Sabah, Bashar, Hashim H. Kareem Aldhahi et Awad A.S. Al-Zergani. « Al-kut Dam Sediments Content of Some Heavy Metals and Its Relationship with Pollution ». Al-Qadisiyah Journal For Agriculture Sciences (QJAS) (P-ISSN : 2077-5822 , E-ISSN : 2617-1479) 7, no 2 (19 mars 2018) : 23–35. http://dx.doi.org/10.33794/qjas.vol7.iss2.20.
Texte intégralRésumé :
This study has been carried out in Alkut city the center of Wasit province which is located about 180 km south of the capital Baghdad on one from the most important dams constructed on theriverTigris called Alkut Dam .Four pedons have been selected in this study, two pedons (A,B) are located in the lower part of dam and the other two pedons (C ,D) are located in the upper part of dam , sediments samples analysis for particle size distribution and total & available heavy metals concentration (Ni ، Cd ، Zn ، Pb ،Fe) in the water and sediments.
Results show that the total concentration of nickel ranges between(104.2 - 178.4) mg.kg-1and the higher value has been found in the second depth (156-126)cm for pedon A and the lower value has been found in the second depth (50-30) for pedon D , while total cadmium concentration ranges between (6.1-2.2)mg.kg-1and the higher value has been found in the second depth (35-20) for pedon A at the lower part of dam and the lower value has been found in the sixth depth (73-93cm)for the same pedon , the values for total Zinc concentration ranges between (108-69) mg.kg-1 and the higher value has been found in the fifth depth (73-55)cm for pedon A at the lower part of dam and the lower value has been found in the last depth (120-100cm) for pedonD in the upper part of dam, the results of total lead concentration ranges between (24.2-11.35) mg.kg-1 and the higher value has been found in the first depth (0-20cm)cm for pedon A at the lower part of dam and the lower value has been found in the third depth (60-50cm) for pedonD in the upper part of dam , while the total concentration for iron (Fe) which ranges between (4595-2988) mg.kg-1 the higher value has been found in the second depth (20-50cm) for pedon A at the lower part of dam and the lower value has been found in the seventh depth (111-93cm) for the same pedon .As compared with critical limits , results show that total concentration of heavy metals for Cd, Pb, Zn and Ni in Sediments samples all has exceed the critical limits values except in some depths.
The results for the available heavy metal concentrations show that the available nickel concentration ranges between(33.2-107.4)mg.kg-1 and the higher value has been found in the second depth (20-35)cm for pedon A at the lower part of dam and the lower value has been found in the second depth (30-50) for pedonD in the upper part of dam,while total cadmium concentration ranges between (0.21-0.48)mg.kg-1and the higher value has been found in the first depth (0-20)cm for pedon B at the lower part of dam and the lower value has been found in the sixth depth (73-93cm)for the pedon A at the lower part of dam , the values for the available Zinc concentration ranges between (56-111) mg.kg-1 and the higher value has been found in the tenth depth (191-231)cm for pedon A at the lower part of dam and the lower value has been found in the last depth (120-100cm) for pedonD in the upper part of dam, the results of available lead (pb) concentration ranges between (6.7-20.2) mg.kg-1 and the higher value has been found in the first depth (0-20cm)cm for pedon A at the lower part of dam and the lower value has been found in the third depth (60-50cm) for pedonD in the upper part of dam , while the available concentration for iron (Fe) which ranges between (39-74)mg.kg-1 the higher value has been found in the second depth (20-50cm) for pedon A at the lower part of dam and the lower value has been found in the eighth depth(111-126) for the same pedon,at the comparison of results for the available concentrations of the studied heavy metals it can be seenthat all values have exceeded the critical limits values according to Nunes etal 2014. in the other hand the results show that there is significant correlation between the total and available concentration for same heavy metalspairs of the correlation (r2) between the available and total concentration was 0.90 , 0.74 , 0.99, 0.99 and 0.58 for Ni , Cd , Zn , Pb and Fe respectively , in the other hand, the results show that the water concentration for heavy metals are 1.7 , 0.03 ,15 , 0.07 and 27 mg.l-1for Ni , Cd , Zn , Pb and Fe respectively , which indicate that all values have exceeded the critical limits according to Iraqi standards and FAW.
2
Hikmatullah. « Andisols from Tondano Area, North Sulawesi : Properties and Classification ». Journal of Tropical Soils 13, no 1 (1 janvier 2008) : 77–85. http://dx.doi.org/10.5400/jts.2008.v13i1.77-85.
Texte intégralRésumé :
Three pedons of Andisol (TN-1, TN-2 and TN-3) developed from young volcanic materials of the Lokon, Soputan, and Lengkoan volcanoes respectively in the Tondano area, North Sulawesi, were studied in the field, and 18 soil samples were analysed in the laboratory for physical, chemical, and mineralogical properties, and they were classified according to Keys to Soil Taxonomy 2003. The results indicated that all the pedons meet the requirements of the andic soil properties, and thus classified into Andisol order. Pedon TN-1 meets bulk density < 0.90 g cm-3, P retention > 85%, and (Alo + 0.5Feo) content extracted by ammonium oxalate > 2.0%, while pedons TN-2 and TN-3 meet the requirements of P retention > 25%, (Alo + 0.5Feo) content > 0.4%, volcanic glass content > 5%, and value of [%(Alo+0.5Feo) x 15.625 + (% volcanic glass)] is > 36.25. Composition of sand mineral fraction indicate that pedon TN-1 and TN-3 show andesitic to basaltic volcanic materials, whereas pedon TN-2 with high olivin content belongs to basaltic volcanic materials. Clay minerals of all the pedons was dominated by hydrated-halloysite with few of disordered-kaolinite, which indicated a little weathering of the pedons. The pedons were classified at family level as Typic Hapludand, medial, amorphic, isothermic (TN-1), Humic Udivitrand, ashy, amorphic, isothermic (TN-2), and Alfic Hapludand, medial, glassy, isothermic (TN-3).
3
Arocena, J. M., et P. Sanborn. « Mineralogy and genesis of selected soils and their implications for forest management in central and northeastern British Columbia ». Canadian Journal of Soil Science 79, no 4 (1 novembre 1999) : 571–92. http://dx.doi.org/10.4141/s98-071.
Texte intégralRésumé :
Soil properties in central and northeastern British Columbia are strongly influenced by parent materials because of geologically young till, glaciolacustrine, and glaciofluvial deposits. We examined pedogenesis on various parent materials to support studies of long-term forest productivity. We sampled nine pedons developed on till (Bobtail, Lucille Mountain, Skulow Lake, Log Lake, Topley, and Kiskatinaw), glaciofluvial (Bowron), and glaciolacustrine (Aleza Lake 1, 2) deposits. The Skulow Lake pedon is distinctive in the occurrence of talc, while the Lucille Mountain pedon has the only clay fraction in which kaolinite is absent. Other pedons on till contain mica, kaolinite, chlorite, smectite, and vermiculite. The Bowron pedon has mica, kaolinite, and chlorite, while the Aleza Lake pedons have mica, kaolinite, chlorite, and 2:1 expanding minerals. In pedons with low amount of 2:1 expanding clays in the C horizon, mica and chlorite appear to degrade into 2:1 expanding clays, while in pedons with C horizons containing 2:1 expanding clays, mica and chlorite seem stable and the formation of hydroxy-interlayered clays is the predominant process. Podzolization and lessivage are major pedogenic processes, while redoximorphic processes are observed in some pedons with illuvial Bt horizons. Significant soil compaction hazards are presented by the medium and fine soil surface textures. Although clay-rich Bt horizons may benefit soil nutrient regimes, conservation of nutrient-rich forest floors is important, given the low S contents in mineral soils. High contents of feldspars in these soils provide a large reserve of nutrients such as Ca and K. Key words: Clay minerals, parent material, podzolization, lessivage
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Mulyanto, Budi. « MORPHOLOGICAL, PHYSICAL, AND CHEMICAL CHARACTERISTICS OF SOME VOLCANIC SOILS OF MT. GALUNGGUNG ». Jurnal Ilmu Tanah dan Lingkungan 2, no 1 (1 avril 2009) : 25–32. http://dx.doi.org/10.29244/jitl.2.1.25-32.
Texte intégralRésumé :
Results of the study on morphological, physical, and chemical characteristics of three pedons developed on volcanic materials of Mt. Galunggung, namely BM1, 8M2, and 8M3, showed that these pedons had a different stage of profile development. Pedon BM1 is classified as undeveloped, 8M2 is medium developed, and 8M3 is strongly developed. This is mainly caused by differences in the relative age of the parent rocks and elevation. Although classified as undeveloped, the soil represented by pedon BM1, the youngest, has immediately been used by farmers for rice cultivation because of water abundance, and high availability of P, and basic cations derived from weathering of easily weathered amorphous materials and minerals. According to the Soil Taxonomy system of the USDA (Soil Survey Staff, 1996), pedons 8M1, 8M2, and 8M3 are classified as Typic Udipsamment, Taptho Hapludandic Typic Troporthent, and humic Hapludult, respectively. Whilst, according to the FAO/UNESCO system (1988), these pedons are classified as Eutric Regoso/, Eutric Regosol and Humic Aliso/, respectively.
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Yli-Halla, Markku. « Classification of acid sulphate soils of Finland according to Soil Taxonomy and the FAO/Unesco legend ». Agricultural and Food Science 6, no 3 (1 septembre 1997) : 247–58. http://dx.doi.org/10.23986/afsci.72788.
Texte intégralRésumé :
In order to place acid sulphate soils (a.s. soils) of Finland in an international context, five pedons from cultivated a.s. soils from Liminka, Ylistaro and Laitila on the western coast of Finland were analyzed and classified according to Soil Taxonomy and the revised legend of the FAO/Unesco Soil Map of the World. Three of the pedons (Liminka 1 and 2, Laitila 1) had sulfuric horizons within 50 cm of soil surface and qualify as Typic Sulfaquepts. One pedon (Ylistaro) had a sulfuric horizon at the depth of 100-150 cm and was classified as a Sulfic Cryaquept. The fifth pedon (Laitila 2) did not have either a sulfuric horizon or sulfidic materials, but it had a pH
6
Hugelius, G., J. G. Bockheim, P. Camill, B. Elberling, G. Grosse, J. W. Harden, K. Johnson et al. « A new data set for estimating organic carbon storage to 3 m depth in soils of the northern circumpolar permafrost region ». Earth System Science Data 5, no 2 (23 décembre 2013) : 393–402. http://dx.doi.org/10.5194/essd-5-393-2013.
Texte intégralRésumé :
Abstract. High-latitude terrestrial ecosystems are key components in the global carbon cycle. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify stocks of soil organic carbon (SOC) in the northern circumpolar permafrost region (a total area of 18.7 × 106 km2). The NCSCD is a geographical information system (GIS) data set that has been constructed using harmonized regional soil classification maps together with pedon data from the northern permafrost region. Previously, the NCSCD has been used to calculate SOC storage to the reference depths 0–30 cm and 0–100 cm (based on 1778 pedons). It has been shown that soils of the northern circumpolar permafrost region also contain significant quantities of SOC in the 100–300 cm depth range, but there has been no circumpolar compilation of pedon data to quantify this deeper SOC pool and there are no spatially distributed estimates of SOC storage below 100 cm depth in this region. Here we describe the synthesis of an updated pedon data set for SOC storage (kg C m−2) in deep soils of the northern circumpolar permafrost regions, with separate data sets for the 100–200 cm (524 pedons) and 200–300 cm (356 pedons) depth ranges. These pedons have been grouped into the North American and Eurasian sectors and the mean SOC storage for different soil taxa (subdivided into Gelisols including the sub-orders Histels, Turbels, Orthels, permafrost-free Histosols, and permafrost-free mineral soil orders) has been added to the updated NCSCDv2. The updated version of the data set is freely available online in different file formats and spatial resolutions that enable spatially explicit applications in GIS mapping and terrestrial ecosystem models. While this newly compiled data set adds to our knowledge of SOC in the 100–300 cm depth range, it also reveals that large uncertainties remain. Identified data gaps include spatial coverage of deep (> 100 cm) pedons in many regions as well as the spatial extent of areas with thin soils overlying bedrock and the quantity and distribution of massive ground ice. An open access data-portal for the pedon data set and the GIS-data sets is available online at http://bolin.su.se/data/ncscd/. The NCSCDv2 data set has a digital object identifier (doi:10.5879/ECDS/00000002).
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Oliveira, Lindomário Barros de, Maria da Graça de Vasconcelos Xavier Ferreira et Flávio Adriano Marques. « Characterization and classification of two soils derived from basic rocks in Pernambuco State Coast, Northeast Brazil ». Scientia Agricola 61, no 6 (décembre 2004) : 615–25. http://dx.doi.org/10.1590/s0103-90162004000600009.
Texte intégralRésumé :
Geomorphic surfaces that present soils derived from basic rocks under warm and humid climate are unique scenarios for studying tropical soils. This paper aimed to characterize and classify two pedons derived from basalt at the Atlantic Forest Zone, Pernambuco State, Northeastern coast of Brazil. Two representative pedons (P1 and P2) were selected on a hillslope at the Cabo de Santo Agostinho municipality. Field macromorphological descriptions were carried out and soil horizon were sampled for physical, chemical, mineralogical and micromorphological characterization. The soils were classified, according to the Brazilian System of Soil Classification (and US Soil Taxonomy) as: "Latossolo Vermelho-Amarelo distroférrico argissólico" (Typic Hapludox) (P1) and "Nitossolo Vermelho distroférrico típico" (Rhodic Paleudult) (P2). Pedon 1 differs from Pedon 2 in some aspects. For instance, P1 presents more yellowish colors, absence of clay illuviation, more friable consistence and the prismatic structure undergoes transformation to angular and subangular blocks. Pedon 2 presents ferri-argilans and leptocutans which indicate that vertical and lateral illuviation of clay is an active process in their formation. These chemically poor and mineralogically uniform soils are a result of the high temperature and rainfall of the studied area.
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Bomfim, Marcela Rebouças, Jorge Antonio Gonzaga Santos, Oldair Vinhas Costa, Xosé Luis Otero, Geraldo da Silva Vilas Boas, Valdinei da Silva Capelão, Edson de Souza dos Santos et Paulo Gabriel Soledade Nacif. « Genesis, Characterization, and Classification of Mangrove Soils in the Subaé River Basin, Bahia, Brazil ». Revista Brasileira de Ciência do Solo 39, no 5 (octobre 2015) : 1247–60. http://dx.doi.org/10.1590/01000683rbcs20140555.
Texte intégralRésumé :
ABSTRACT Preservation of mangroves, a very significant ecosystem from a social, economic, and environmental viewpoint, requires knowledge on soil composition, genesis, morphology, and classification. These aspects are of paramount importance to understand the dynamics of sustainability and preservation of this natural resource. In this study mangrove soils in the Subaé river basin were described and classified and inorganic waste concentrations evaluated. Seven pedons of mangrove soil were chosen, five under fluvial influence and two under marine influence and analyzed for morphology. Samples of horizons and layers were collected for physical and chemical analyses, including heavy metals (Pb, Cd, Mn, Zn, and Fe). The moist soils were suboxidic, with Eh values below 350 mV. The pH level of the pedons under fluvial influence ranged from moderately acid to alkaline, while the pH in pedons under marine influence was around 7.0 throughout the profile. The concentration of cations in the sorting complex for all pedons, independent of fluvial or marine influence, indicated the following order: Na+>Mg2+>Ca2+>K+. Mangrove soils from the Subaé river basin under fluvial and marine influence had different morphological, physical, and chemical characteristics. The highest Pb and Cd concentrations were found in the pedons under fluvial influence, perhaps due to their closeness to the mining company Plumbum, while the concentrations in pedon P7 were lowest, due to greater distance from the factory. For containing at least one metal above the reference levels established by the National Oceanic and Atmospheric Administration (United States Environmental Protection Agency), the pedons were classified as potentially toxic. The soils were classified as Gleissolos Tiomórficos Órticos (sálicos) sódico neofluvissólico in according to the Brazilian Soil Classification System, indicating potential toxicity and very poor drainage, except for pedon P7, which was classified in the same subgroup as the others, but different in that the metal concentrations met acceptable standards.
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Hugelius, G., C. Tarnocai, J. G. Bockheim, P. Camill, B. Elberling, G. Grosse, J. W. Harden et al. « Short communication : a new dataset for estimating organic carbon storage to 3 m depth in soils of the northern circumpolar permafrost region ». Earth System Science Data Discussions 6, no 1 (25 avril 2013) : 73–93. http://dx.doi.org/10.5194/essdd-6-73-2013.
Texte intégralRésumé :
Abstract. High latitude terrestrial ecosystems are key components in the global carbon (C) cycle. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify stocks of soil organic carbon (SOC) in the northern circumpolar permafrost region (18.7 × 106 km2). The NCSCD is a digital Geographical Information systems (GIS) database compiled from harmonized regional soil classification maps, in which data on soil coverage has been linked to pedon data from the northern permafrost regions. Previously, the NCSCD has been used to calculate SOC content (SOCC) and mass (SOCM) to the reference depths 0–30 cm and 0–100 cm (based on 1778 pedons). It has been shown that soils of the northern circumpolar permafrost region also contain significant quantities of SOC in the 100–300 cm depth range, but there has been no circumpolar compilation of pedon data to quantify this SOC pool and there are no spatially distributed estimates of SOC storage below 100 cm depth in this region. Here we describe the synthesis of an updated pedon dataset for SOCC in deep soils of the northern circumpolar permafrost regions, with separate datasets for the 100–200 cm (524 pedons) and 200–300 cm (356 pedons) depth ranges. These pedons have been grouped into the American and Eurasian sectors and the mean SOCC for different soil taxa (subdivided into Histels, Turbels, Orthels, Histosols, and permafrost-free mineral soil taxa) has been added to the updated NCSCDv2. The updated version of the database is freely available online in several different file formats and spatial resolutions that enable spatially explicit usage in e.g. GIS and/or terrestrial ecosystem models. The potential applications and limitations of the NCSCDv2 in spatial analyses are briefly discussed. An open access data-portal for all the described GIS-datasets is available online at: http://dev1.geo.su.se/bbcc/dev/v3/ncscd/download.php. The NCSCDv2 database has the doi:10.5879/ECDS/00000002.
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Salinas, Andrea, et Bryan Tillaguango. « Crecimiento económico e inversión extranjera directa y su incidencia en la desigualdad a nivel mundial : un enfoque de cointegración y causalidad en datos de panel ». Revista Vista Económica 10, no 1 (19 mars 2022) : 87–99. http://dx.doi.org/10.54753/rve.v10i1.1295.
Texte intégralRésumé :
El objetivo de esta investigación, es analizar el nexo entre el Índice de Gini, el crecimiento económico y la inversión extranjera directa (IED) en 100 países a nivel mundial, periodo 1980-2015. Se implementó técnicas de cointegración de datos de panel, como son los modelos de cointegración de Pedoni (1999) que evalúa el largo plazo, mientas que, para el corto plazo se implementó la prueba de cointegración de Westerlund (2007). Asimismo, para obtener la fuerza del vector de cointegración se utilizó modelos de Mínimos Cuadrados Ordinarios Dinámicos (DOLS) y Mínimos Cuadrados Ordinarios Dinámicos (PDOLS). En el caso de la causalidad se implementó la prueba propuesta por Dumitrescu /& Hurlin (2012). Los resultados de las pruebas de cointegración nos muestran que el Índice de Gini, el crecimiento económico y la IED tienen un movimiento conjunto a corto y largo plazo. Los modelos PDOLS y DOLS muestran que el vector de cointegración entre el Índice de Gini y el crecimiento económico es más contundente en los PIMB y PIMA. Por otra parte, los resultados de la causalidad de Dumitrescu & Hurlin (2012) confirman la existencia de causalidad bidireccional entre la desigualad y el producto interno bruto en los países de ingresos medios bajos (PIMB).
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Chittleborough, D. J., M. S. Tejan-Kella et R. W. Fitzpatrick. « Genesis of podzols on coastal dunes in southern Queensland. V. Chemistry and mineralogy of the non-opaque heavy mineral fraction ». Soil Research 36, no 4 (1998) : 699. http://dx.doi.org/10.1071/s97041.
Texte intégralRésumé :
Eight podzols on coastal dunes from the Cooloola chronosequence, and an associated pedon from North Stradbroke Island (Amity), were studied to establish (i) the degree of homogeneity of the parent material between and within profiles, (ii) the extent of heavy mineral weathering, and (iii) whether the parent sediments of each pedon had a common proximate source. The pedons are Quartzipsamments and Troporthods with ages ranging from Holocene to Pleistocene. On the basis of ratios zircon : rutile, zirconium : titanium, and non-magnetic : very magnetic heavy minerals in the fine sand fraction (53–125 µm), we concluded that the parent materials of the Cooloola pedons were mineralogically similar. By using zirconium in the non magnetic heavy mineral fraction as an index for zircon, it is evident that there has been considerable pedogenetic weathering of the heavy mineral fraction. There is a statistically insignificant difference in hafnium concentrations of zircons which implies that parent sediments of the soils at Cooloola and North Stradbroke Island were derived from a common immediate source.
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Peter, Kaananwii Dum, et Lesi Dike Gbaraneh. « Land suitability assessment of soils for rubber and cashew cultivation in the Coastal Area of Bodo City, Rivers State, Southern Nigeria ». Ilmu Pertanian (Agricultural Science) 6, no 3 (29 novembre 2021) : 175. http://dx.doi.org/10.22146/ipas.65575.
Texte intégralRésumé :
The research was carried out in Bodo city in Gokana Local Government of Rivers State, Southern Nigeria to evaluate the land suitability for rubber and cashew cultivation using the relevant land suitability guidelines for the cultivation of the two cash crops of interest. Mapping of the 100 ha of land in Bodo city was done using the rigid grid method of soil survey. The three mapping units (summit, middle slope and valley bottom) were identified and delineated. Three representative soil pedons of 2 m x 2 m x 2 m were dug and described by horizon from top to bottom (0 cm to 200 cm). Soil samples were collected from identifiable horizons and processed for laboratory analysis using standard routine laboratory methods most appropriate. The results showed that pedons 1 and 3 covering 86,000 ha of the entire study area were found to be moderately suitable for rubber cultivation with limitation in soil physical characteristics (texture) and fertility (low base saturation < 50 %). Pedon 2 covering 14,000 ha of the total land of the study area was marginally suitable due to limitation in soil fertility (low base saturation < 80 %). Pedon 1, 2, and 3 were also moderately suitable for cashew cultivation in the study area with limitation in soil physical characteristics (texture) and fertility (low organic carbon), while limitation in wetness (poor drainage) was peculiar to pedon 3 only. Thus, soils in the study area were moderately suitable for both rubber and cashew cultivation in the area.
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WALL, G. J., et M. MARSH. « WITHIN-PEDON VARIABILITY OF TRACE METALS IN SOUTHERN ONTARIO ». Canadian Journal of Soil Science 68, no 1 (1 février 1988) : 53–61. http://dx.doi.org/10.4141/cjss88-005.
Texte intégralRésumé :
Replicate soil samples (three to six) from the surface (A), subsurface (B) and parent material (C) horizons of agricultural soils were collected from 10 pedons to measure within-pedon variability of nine elements (Cu, Zn, Mn, Sr, Co, Ni, Pb, Li, Cr). Elemental variability was examined in relation to the mode of deposition of the soil parent material, soil horizonation and soil drainage. Within-pedon variability as measured by the coefficient of variation (CV) ranges from low (CV < 10%) for Sr, Co, Li to intermediate (CV 10–20%) for Ni, Mn, Pb, Cr to high (CV > 20%) for Cu, Zn. Within-pedon variability of six (Cu, Sr, Co, Ni, Pb, Li) of the nine elements studied displayed no significant differences in variance due to horizon, drainage or mode of deposition. The number of replicate samples required for statistically reliable evaluation of a pedon at given confidence limits was determined for the elements studied. The number of samples required to estimate mean elemental concentrations (± 10%) ranged from 1 to 23. The study results emphasize the need for basing the design of field sampling procedures on existing knowledge of the relevant soil property within the context of the specific purpose of the study. Key words: Trace metal, variability, within-pedon
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Pessoti, J. E. S., J. L. I. Demattê, J. R. J. Rueda et A. Marconi. « Relação entre fisiografia e solos desenvolvidos de material cenozoico da região do rio Jequitai, MG ». Anais da Escola Superior de Agricultura Luiz de Queiroz 46, no 2 (1989) : 495–518. http://dx.doi.org/10.1590/s0071-12761989000200014.
Texte intégralRésumé :
É estudado o relacionamento entre a fisiografia e os solos evoluídos a partir de sedimentos cenozóicos, de textura e composição variáveis, depositados sob a ação do rio São Francisco e tributários. A região (vale do rio Jequitai, MG) é caracterizada por um clima sub-úmido, onde o regime de umidade do solo é ústico e o de temperatura isotérmico. Foram coletados 5 pedons dispostos numa topossequência. Na posição mais antiga (pleistocênica), o solo apresenta-se em um estágio de intensa alteração (Typic Haplustox). Os demais solos encontram-se sobre sedimentos holocênicos, compondo a planície aluvial do rio São Francisco e são, mineralogicamente, mais jovens, com horizonte argílico, representado por ultissol e molissol, ocorrência esta pouco comum em situações de planície aluvial recente. No pedon 1 (Typic Haplustox), os minerais primários intemperizáveis inexistem na fração grosseira. O pedon 2 (Plinthic Haplustult) apresenta na fração areia um acréscimo em profundidade de minerais de fácil alteração. Na fração silte, os feldspatos já estão em fase de alteração. Os pedons 3 (Oxic Plintaquult), 4 (Fluventic Plinthustult) e 5 (Fluventic Argiustol) mostram elevadas proporções de minerais primários de fácil alteração (placioclásios calco-sódicos, hornblenda), principalmente nas frações areia e silte. A ocorrência destes minerais associa-se a um processo deposicional recente, aliado às condições de clima e drenagem locais.
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Ajala, O. N., T. A. Adjadeh, J. O. Olaniyan, T. O. Isimikalu, E. K. Nartey et F. O. James. « Characterization, classification and suitability evaluation of soils under sugarcane (Saccharum officinarum L.) cultivation at the Sugar Research Farm, University of Ilorin, Nigeria ». Agro-Science 20, no 3 (29 septembre 2021) : 14–23. http://dx.doi.org/10.4314/as.v20i3.3.
Texte intégralRésumé :
A reconnaissance survey conducted at the University of Ilorin Sugar Research Farm (USRF) revealed four dominant soils at Site 1 (USRF1) and one at Site 2 (USRF2). The soils were characterized and classified according to both the Soil Taxonomy (ST) and the World Reference Base for Soil Resources (WRB). Also, the suitability of the soils for sugarcane cultivation was evaluated using the limitation approach. While the USRF1 soils were reddish, the USRF2 soil was greyish due to poor drainage. The USRF1 soils were loamy sand with the AB-horizons of pedons II and III being gravelly. Pedon V had sandy loam surface, sandy clay loam subsurface and clay loam subsoil. The USRF1 soils were moderately acid while the USRF2 soil was slightly acid to slightly alkaline. Exchangeable calcium (Ca2+) content of the USRF2 soil which averaged 4.00 cmolc kg–1 was 2-3 times higher than that of the USRF1 soils. The USRF2 soil also contained higher Mg2+, K+ and Na+, 2-3 folds higher effective cation exchange capacity and > 10 folds higher soil organic carbon (with mean of 11.60 g kg–1) and total nitrogen (mean of 0.94 g kg–1). Under ST, pedons I and IV classified as Typic Haplustepts, II and III as Lithic Haplustepts and V as a Kanhaplic Haplustalf. Under WRB, pedons I and IV classified as Eutric Regosols (arenic), II and III as Endo-pisoplinthic Cambisols (arenic) and V as a Gleyic Lixisol (loamic). Pedon V was highly suitable (85.25%), I and IV moderately suitable (64.53%), II marginally suitable (47.40%) and III unsuitable (35.62%) for sugarcane cultivation.
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Veenstra, Jessica J., et C. Lee Burras. « Effects of agriculture on the classification of Black soils in the Midwestern United States ». Canadian Journal of Soil Science 92, no 3 (mars 2012) : 403–11. http://dx.doi.org/10.4141/cjss2010-018.
Texte intégralRésumé :
Veenstra, J. J. and Burras, C. L. 2012. Effects of agriculture on the classification of Black soils in the Midwestern United States. Can. J. Soil Sci. 92: 403–411. Soil surveys are generally treated as static documents. Many soil survey users assume that pedon data generated 30 to 50 yr ago still represents today's soil, as short-term changes in soil properties are perceived to be limited to the soil surface and thus pedologically insignificant. In this study, we re-sampled and re-analyzed 82 pedons with historical descriptions and laboratory data in Iowa, United States, to evaluate changes in soil profile properties and taxonomic classification after approximately 50 yr of agricultural land use. Using historical and current data, we classified sampled pedons using Canadian Soil Taxonomy, US Soil Taxonomy and the Food and Agriculture Association World Reference Base (FAO-WRB). Our results show that soil characteristics have changed significantly enough to change the classification. In each taxonomic system, the classification of 60% or more of the sampled pedons differed from the original. Classification of 15 to 32% of the sampled pedons changed at the Order (or equivalent) level with 11 to 33% of the pedons originally classified as Black soils – Mollisols, Chernozems or Phaeozems – no longer classified as Black soils. The change in soil classification over such a short-time period challenges the validity and usefulness of treating existing soil maps as static documents as well as traditional soil classification hierarchies.
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Schaller, Mirjam, Igor Dal Bo, Todd A. Ehlers, Anja Klotzsche, Reinhard Drews, Juan Pablo Fuentes Espoz et Jan van der Kruk. « Comparison of regolith physical and chemical characteristics with geophysical data along a climate and ecological gradient, Chilean Coastal Cordillera (26 to 38° S) ». SOIL 6, no 2 (16 décembre 2020) : 629–47. http://dx.doi.org/10.5194/soil-6-629-2020.
Texte intégralRésumé :
Abstract. We combine geophysical observations from ground-penetrating radar (GPR) with regolith physical and chemical properties from pedons excavated in four study areas spanning 1300 km of the climate and ecological gradient in the Chilean Coastal Cordillera. Our aims are the following: (1) to relate GPR observations to depth-varying regolith physical and weathering-related chemical properties in adjacent pedons and (2) to evaluate the lateral extent to which these properties can be extrapolated along a hillslope using GPR observations. Physical observations considered include regolith bulk density and grain size distribution, whereas chemical observations are based on major and trace element analysis. Results indicate that visually determined pedolith thickness and the transition from the B to C horizons generally correlate with maximums in the 500 and 1000 MHz GPR envelope profiles. To a lesser degree, these maximums in the GPR envelope profiles agree with maximums in weathering-related indices such as the chemical index of alteration (CIA) and the chemical index of mass transfer (τ) for Na. Finally, we find that upscaling from the pedon to hillslope scale is possible with geophysical methods for certain pedon properties. Taken together, these findings suggest that the GPR profiles down hillslopes can be used to infer lateral thickness variations in pedolith horizons in different ecologic and climate settings, and to some degree the physical and chemical variations with depth.
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Djaenudin, D. « Some Spesific Soil Characteristics of Andisols as Series Differentiae : A Case Study of Cikajang and Cikole Regions, West Java ». Jurnal Ilmu Tanah dan Lingkungan 6, no 1 (1 avril 2004) : 14–21. http://dx.doi.org/10.29244/jitl.6.1.14-21.
Texte intégralRésumé :
The objective of this research was to study speczfic soil characteristics of Andisols as series differentiae. Five pedons ofCikajang and Cikole regions were studied. Both regions belong to the wet climate, udic soil moisture regime and isothermictemperature regime. As much as 32 soils samples were taken for analysis of physical, chemical and mineralogical propertiesfollows the standard procedures of The Central Research and Development of Soil and Agroclimate laboratory. The speczficsoil properties can be used for soil series dzflerentiae of each soil family. In soil family level, pedon Dn-1, Dn-2, and Dn-4 are classtfied as Typic Hapludand, medial-mixed, isothermic, and pedon Dn-3 and Dn-5 are classrjied as Thaptic Hapludand,medial-mixed, isothermic. Each soil family consists of two soil series. The properties of buried soil, color, texture, and soilreaction are used for soil series dzflerentiae.
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Azeez, Salim Neimat. « Effects of Some local Conditions on Leaching Factor of Aridisols in Kalar/Garmian, Kurdistan- Iraq ». Kurdistan Journal of Applied Research 1, no 2 (18 décembre 2016) : 20–25. http://dx.doi.org/10.24017/science.2016.1.2.1.
Texte intégralRésumé :
Five sites were selected in Kalar city on different topographic position. The mean annual rainfall of the study area about 280 mm with about 24.5 C° mean annual temperature. The study area used for rain feed crop production. Morphological properties of the studied pedons indicated that all pedons were developed with Ochric epipedons and Cambic and Argillic endopedons .The results of particle size distribution show a wide differences between sand and clay in surface horizons except pedon (2) because of low elevation compared with other pedons. Moreover, the results of exchangeable sodium and potassium indicate that pedons (4) and (5) had the lowest value of soil leaching factor which is an indication of the high activity of weathering and leaching processes. In another hand, the results of total element analysis has observed that the silicate ratio were high to indicate the high leaching processes which is the proof of the existence of fine materials movement particularly clay colloids, this is not merely due to the rare rainy weather conditions that are prevalent recently but is a result of wet paleoclimatic conditions, and this movement eventually occurred due to in situ factors. All soils are belonged to Aridisols order with suborders Argids and Cambidsas these soils are in aridic moisture regime include Ochric diagnostic surface horizon with Argillic and Cambic diagnostic subsurface horizons.
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Sahoo, J., mr Dinesh, A. Dass, M. A. Bhat, H. S. Gouda et mr Anurag. « Land suitability assessment for improved land use planning in selected watersheds of Haryana ». Journal of Environmental Biology 42, no 2 (1 mars 2021) : 285–94. http://dx.doi.org/10.22438/jeb/42/2/mrn-1402.
Texte intégralRésumé :
Aim: The current study aimed to evaluate the capacity and suitability of land for semi-arid region of Haryana in selected watersheds to identify the major limitations of crop production. Methodology: The study was carried out in Bhiwani district of Haryana in 2017 where eight typical pedons (P) representing four micro-watersheds viz., Motipura (P1 and P2), Sainiwas (P3 and P4), Jhumpa (P5 and P6), Budhsheli (P7 and P8) were studied. Results: The studied pedons were neutral to alkaline in reaction (pH 6.87-9.10), non-saline (EC 0.02-0.21 dS m-1) and low in organic carbon (OC) (0.06-0.27%). Available N, P, K and S were low (42.00-189.00 kg ha-1), low to medium (4.20-17.10 kg ha-1), low to high (62.20-326.50 kg ha-1) and low (0.40-19.20 mg kg-1) in the studied pedons, respectively. Soils were deficient in available Fe and Zn but marginal to sufficient in available Mn and Cu. Interpretation: Soils were classified as IIsf and IIItsf and S3s and N1s according to LCC and irrigation suitability, respectively. The pedons were found suitable (S1) to moderately suitable (S2) for guar (cluster bean), oilseeds (mustard), moderately suitable (S2) to marginally suitable (S3) for pearl millet, gram and forestry, and marginally suitable (S3) for cotton and wheat. Key words: Land suitability, Nutrients, Pedon, Semiarid, Watershed
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Arifin, Mahfud, Ganjar Herdiansyah, Apong Sandrawati et Rina Devnita. « Karakterisasi dan Klasifikasi Ultisols Yang Berkembang dari Dua Bahan Induk di Kabupaten Serang, Provinsi Banten ». soilrens 19, no 2 (14 février 2022) : 33. http://dx.doi.org/10.24198/soilrens.v19i2.38362.
Texte intégralRésumé :
The effort to utilize the soils optimally, especially Ultisols, requires an appropriate understanding related to their characteristics. The characteristics of Ultisols are sturdily influenced by soil-forming factors, viz. climate, parent material, pedogenic age and topography. The purposes of this study were to determine the chemical, physical, mineralogical characteristics and soil development classification level of Ultisol from two different types of parent rock. This research was conducted in Kampungbaru Village, Petir District and Sukalaksana Village, Curug District, in Serang Regency, Banten Province. These two villages represented different parent materials, namely andesite lava parent material of Holocene age (Kampungbaru Village) and tuff dacite parent material of early Pleistocene age (Sukalaksana Village). The research method was descriptive, comparative and survey. Soil classification was based on the Soil Survey Staff. The results showed that Ultisols developed from dacite tuff and andesite lava did not show contrasting differences in soil properties. The level of weathering of the two pedons was at the senile stage and the level of soil development of the two pedons was at the argillic stage. The soil classification of Kampungbaru pedon was Typic Palehumults, very fine, kaolinitic, isohyperthermic, while the Sukalaksana pedons was Arenic Paleudults, fine, kaolinitic, isohyperthermic
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Delfianto, Rizki, Mochtar Lutfi Rayes et Christanti Agustina. « MORFOLOGI DAN KLASIFIKASI TANAH PADA TOPOSEKUEN LERENG BARAT GUNUNG KELUD, KEDIRI, JAWA TIMUR ». Jurnal Tanah dan Sumberdaya Lahan 8, no 2 (1 juin 2021) : 539–52. http://dx.doi.org/10.21776/ub.jtsl.2021.008.2.24.
Texte intégralRésumé :
The research that was conducted from April to December 2020 in the Supiturung Micro-Watershed, located on the western slope of Mount Kelud, Kediri was aimed to study the morphological characteristics and soil classification using a topo-sequence approach. Four pedons were observed across the physiographic positions (upper, middle and lower slopes) on dry-land farming land use. The method used in this research included 8 stages, namely the preparation stage, pre-survey, map making, field observations, laboratory analysis, soil classification, data processing, and reporting. On the field, cross-sectional profiles were carried out on four selected pedons by testing the soil profile measuring 1 x 1 meter with a depth of 150-200 cm, followed by soil horizon, soil thickness, texture, structure, consistency, effective depth, type and number of pores, as well as other characteristics. Soil samples were collected from the genetic horizon of the pedons for being analyzed using standard procedures, then taken to the laboratory for soil physical and chemical analysis. Soil morphology with physicochemical properties was then classified based on the Keys Taxonomy of Soil to the Sub Group level. The results showed that each pedon has a different Sub Group. This condition can be caused by many factors, such as differences in epipedon thickness, base saturation values, organic C levels, and other morphological conditions at the time of direct observation. Four pedons have lithologic discontinuities, recognition of these types of lithologic changes is important because pedogenesis and pedogenic interpretations are greatly influenced by changes in the parent material.
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Purwanto, Setiyo, Rachmat Abdul Gani et Erna Suryani. « Characteristics of Ultisols derived from basaltic andesite materials and their association with old volcanic landforms in Indonesia ». SAINS TANAH - Journal of Soil Science and Agroclimatology 17, no 2 (30 décembre 2020) : 135. http://dx.doi.org/10.20961/stjssa.v17i2.38301.
Texte intégralRésumé :
<p>The common problem with Ultisols is their low pH and soil fertility, with liming and fertilization being common solutions to overcome this problem; however, studies on Ultisol soil parent materials are still rare. This study aimed to examine the characteristics of Ultisols derived from andesite and basaltic andesite parent materials. In 2016–2017, five Ultisol pedons (P8, P9, P10, P11, and P15) were sampled from basaltic andesites and other associations. The five pedons consisted of 19 soil samples. The chemical and mineralogical properties of the soils were analyzed. It was found that the color of the basaltic andesite Ultisols varied from hue of 2.5 YR to 10 YR, with value of 3–5 and chroma of 2–8. The Ultisols derived from andesite/diorite (P8) were dominated by rock fragments (52–77%), while those derived from andesitic breccia (P9) were dominated by opaques (62–67%), those from basaltic andesite tuff/lava by weathering minerals (44–52%) and hydragilite (28–34%), those from basaltic andesite (P11) by quartz (48%) and (P15) by opaques (79–89%). The mineral reserves varied from very low (0–4%) in pedons P8, P9, P11, and P15 to very high (> 40%) in pedon P10. The results of this study are expected to be used as a guide for future agricultural development on Ultisols.</p>
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Sanborn, P. « Topographically controlled grassland soils in the Boreal Cordillera ecozone, northwestern Canada ». Canadian Journal of Soil Science 90, no 1 (1 février 2010) : 89–101. http://dx.doi.org/10.4141/cjss09048.
Texte intégralRésumé :
Properties and ecological relationships of grassland soils were examined at three widely separated sites (Stikine River Valley, British Columbia, and Carmacks and Kluane Lake, Yukon) in the Boreal Cordillera ecozone of northwestern Canada. At these latitudes (58 to 62°N), grasslands are largely restricted to south-facing aspects, and usually occur as islands within the boreal forest. The grayish and yellowish brown, base-rich, Ah horizons had a thickness-weighted mean organic carbon concentration of 19.5 g kg-1. Ah horizons exhibited a range of microstructures similar to that documented in grassland soils in the southern Cordillera and Great Plains, ranging from spongy to massive in the young loess-derived Kluane Lake pedon to well-developed crumb microstructure in the finer-textured Stikine pedon. These pedons met the morphological and chemical criteria, and likely the soil climate requirements, for the Dark Brown and Brown great groups of the Chernozemic order of the Canadian System of Soil Classification (3rd ed.). Key words: Grassland, Boreal Cordillera, Chernozem, soil micromorphology, soil genesis, soil classification
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N. Usmana, Makhai, Jude S. Karma, Angyu M. Dantani et Victor D. Joro. « CHARACTERIZATION AND CLASSIFICATION OF SOILS ALONG RIVER DONGA, DONGA, TARABA STATE, NIGERIA ». International Journal of Agriculture, Environment and Bioresearch 07, no 04 (2022) : 235–50. http://dx.doi.org/10.35410/ijaeb.2022.5758.
Texte intégralRésumé :
This study was carried out to ascertain the characterization and classification of soils along river Donga in Donga local government area of Taraba State. Three profile pits were dug on the flat terrain for the physio-chemical properties of the soils. The pits were described and samples were collected for routine laboratory analysis for the selected physio-chemicals properties. Data collected were analyzed statistically using analysis of variance (ANOVA) The result of the laboratory analysis of the physical and chemical properties indicated that particle size distribution of sand particle dominated other fraction of fine earth materials. This can be attributed to the parent materials that gave rise to the soils.The pH (H2O) was slightly acidic in reaction in all the pedons studied (6.44, 5.82 and 5.67). The organic carbon content ranges from very low to low compared to the maximum level (5%) for tropical soils. Available phosphorus obtained exceeded the critical limits of 8.0 to >18mg/kg, which indicates that the available phosphorus were high. The exchangeable bases (Ca, Mg, K & Na) as indicated in the table 3 that Ca, Mg, K & Na were low in all the pedons studied. The results obtained from analyzed profile samples showed that percentage (%) base saturation values for all the pedons were high. The Correlation was done to determine non-significant and significant values among soil physio-chemical properties studied at 5% and 1% probability level. In addition, after the profile description and examination of the soil properties of the study area, the soils were classified using USDA soil taxonomy (2014). Pedons 1 and 2 are classified into the order of Alfisols and sub-group of Typical Haplustalf while pedon 3 is also classified into Alfisols but sub-group of Arenickandiustals (Hypereuticlixisels).
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Gus, M., et M. Drewnik. « Evolution of sandy soils within deflation hollows in shifting areas of sand – a case study from the Błędów Desert (Poland) ». Soil and Water Research 12, No. 3 (28 juin 2017) : 161–69. http://dx.doi.org/10.17221/36/2016-swr.
Texte intégralRésumé :
Areas of shifting sand are important places for testing the effects of abiotic and biotic factors on soil morphology and evolution, where aeolian processes cause dynamic changes in the natural environment. The main aim of the study was to determine the evolution of soils within deflation hollows in shifting sands. In the context of this purpose, representative study areas were selected: (1) a reference surface in a plantation forest with soils undisturbed by aeolian processes – one pedon, (2) an active deflation hollow – two pedons, (3) a deflation hollow stabilized by reforestation (forest planting ca. 30 and ca. 100 years ago – two pedons). Soil morphology and micromorphology as well as several physical and chemical properties were analyzed. In a deflation hollow, the studied soils are found at various stages of development, mostly characterized by a relatively rapid accumulation of soil organic matter. A well-developed buried illuvial B horizon as an ‘ortstein’ material can limit aeolian erosion to a certain depth, while above these horizons aeolian erosion and accumulation remain active. History of changes in the environment is to a substantial degree reflected in morphology and micromorphology of the studied soils.
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Osinuga, O. A., V. U. Aiboni et C. O. Oyegoke. « Classification and suitability evaluation of soils along a toposequence for rice production in Alabata, Southwest Nigeria ». Agro-Science 19, no 4 (29 octobre 2020) : 43–50. http://dx.doi.org/10.4314/as.v19i4.8.
Texte intégralRésumé :
Soil classification and suitability evaluation are requirements for attaining optimum utilization of the available land resources. Detailed soil survey of a top sequence at Alabata, Southwest Nigeria was carried out using the rigid grid method. The soils were characterized, classified, and evaluated for rain-fed rice production. The results of the study showed that the soils were loamy sand to sandy clay loam texture, fine to coarse sub-angular blocky structure and loose to hard consistency. Soil reaction ranged from strongly acidic to slightly acidic (pH 4.2-6.1) with low organic carbon (5.6-19.0 g/kg) and total nitrogen (0.5-1.7 g/kg). The potassium contents were moderate while exchangeable cations and available phosphorus were very low. Pedon 1 was classified as KandicPaleustalfs, pedon 2 as TypicHaplustalfs and pedon 3 as Aeric Kandiaqualfs. The index of current productivity (IPc) by linear model ranged between 8.7 and 10.3, while by square root models ranged between 16.2 and 17.5. The values suggested that the soils were not currently suitable (N2 and N1) for rice production. The index of potential productivity (IPp) ranged from 48.5 to57.0 by linear model and from 53.9 and 58.5 for the square root model. Thus, pedons were potentially marginally (S3) and moderately (S2) suitable for the production of rice. The limiting factors were mainly low levels of macro nutrients, organic matter and cation exchange capacity.
Key words: Classification, climate, suitability evaluation, toposequence, rice production
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Okunsebor, Faith Ehinomhen, Aigboghosa Samson Umweni et Lucky Agbogun. « Suitability assessment for oil palm (Elaeis guineensis) and coconut (Cocus nucifera) cultivation in coastal plain sands of South Southern Nigeria ». Ilmu Pertanian (Agricultural Science) 6, no 3 (29 novembre 2021) : 130. http://dx.doi.org/10.22146/ipas.65335.
Texte intégralRésumé :
Some soils of coastal plain sands in South Southern Nigeria were assessed for oil palm and coconut cultivation. This research was carried out to evaluate the soils of the study area using rigid grid soil survey methodology at detailed scale. The study area (128.11 ha) was delineated into four soil mapping units based on soil type. A pedon was sunk in each mapping unit and described according to FAO. Three soil orders, including Entisols (Ahiara), Inceptisols (Kulfo) and Ultisols (Orlu), were identified. Parametric and limitation methods of land suitability evaluation were used. Major limitations to assessment were climate (mean annual temperatures) and soil physical properties (texture/structure). Aggregate suitability rating (both actual and potential) showed that Ultisols (pedons 3 and 4, covering 56.73 ha) was moderately suitable (S2) for coconut and marginally suitable (S3) for oil palm, Inceptisols (pedon 2, covering 54.25 ha) was marginally suitable (S3) for coconut but not suitable (NS) for oil palm, and Entisols (Pedon 1covering 17.13 ha) was not suitable (NS) for any of the crops. Thus, area with Entisols should not be used for cultivation of any of the crops due to major limitation in texture. Moreover, both assessment approaches captured the major limitations. Therefore, the use of any of the approaches employed in this study and for these crops becomes a matter of choice as both of them showed no major differences in the application of their procedures.
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Bekele, Abinet, Sheleme Beyene, Alemayehu Kiflu et Fantaw Yimer. « Genesis and Classification of Termite-Mediated Soils along Toposequences in a Semiarid Area of Southeast Ethiopia ». Applied and Environmental Soil Science 2023 (27 janvier 2023) : 1–15. http://dx.doi.org/10.1155/2023/7150907.
Texte intégralRésumé :
Despite the ecosystem functioning they provide, termite pedoturbation along toposequence is overlooked in the genesis of semiarid soils. Therefore, we aimed to describe morphological and physicochemical properties that lead to the classification of termite-mediated soils. In this study, representative pedons, one on each slope class, were described and classified for five different topographical positions, and the soil properties of genetic horizons were compared to those obtained from respective mounds. The result showed that the soils were heavily manipulated by termites except for the pedon at the toe slope. Cambisols were formed on the summit and back slope and resulted from slow pedogenic processes. Luvisols on the toe slope showed redoximorphic features, and gleization and clay synthesis formed the soil, while the upward movement of coarse particles enhanced textural differentiation. Luvisols at the foot of the slope are formed by the partial destruction of iron-bearing minerals accompanied by eluviation-illuviation processes. Accumulation of calcium carbonate following calcification formed Calcisols on the bottom slope. Comparing the mounds and reference pedons, much of the mound’s soil is mined from the subsoil, usually from B horizons. However, their influence on soil properties depended mainly on the topography. Moreover, the morphological and physicochemical properties of the studied pedons exhibited various degrees of variation along topography and clearly showed topographic effects. In conclusion, termites can be a potent mediator of soil genesis across toposequences, and their activities should be considered in the classification and management of semiarid soils. A further retrospective examination of micromorphological evidence is recommended to support this finding.
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Heeshan, Ahmed Majeed, Ammar S. Ismaeal et Abdulla Azawi Rashid. « Optical, morphological and Physico-chemical Properties For some soils in central and northern Iraq, using a digital camera ». Tikrit journal for agricultural sciences 22, no 1 (31 mars 2022) : 169–84. http://dx.doi.org/10.25130/tjas.22.1.15.
Texte intégralRésumé :
The study was conducted in three selected sites representing the soils of three governorates of central and northern Iraq (Salah al-Din, Kirkuk, and Erbil), to determine the effect of morphological, physical and chemical characteristics of some soil genetic horizons on their spectral reflectivity using digital camera as well as Knowing the degree of soil development and classification according to the Quantitative (American) system for classifying soils, Three pedons representing these soils were excavated, the horizons were morphologically diagnosed and samples were obtained from each horizon of each pedon from the soils of the study sites to conduct some laboratory tests for the physical and chemical properties. Pictures were taken that combine dry and wet samples; In order to calculate the spectral reflectivity and RGB values using ERDAS software. The results revealed a heterogeneity in the morphological characteristics represented by the dominant color class of each pedon, with the diagnosis of the morphological features of each of the surface diagnostic horizon Ochric with the subsurface diagnostic horizons Gypsic, Calcic and Argillic. The results also found that the spectral reflectivity values of RGB were high in dry soil and decreased in the wet condition, and the lowest value of the spectral reflectivity was for the surface horizons, as it reached 44.87% on the surface horizon of the second pedon, and the highest value of the reflectivity was on the horizon Cky1 of the pedon 1, where its ratio is 72.15% ,and the reflectivity values of the red color at the red band were high in pedon Erbil as a result of the effect of iron oxides. Show the spectral and hematological differences represented by the index of brightness (value), hue and index of iron oxides The results also found that the most influential traits in these spectral indices are the dominant soil color as well as the texture of the soil represented by the content of silt and clay with moisture content, as well as the effect of the content of organic matter, iron oxides, gypsum and lime content on the surface and subsurface diagnostic horizons.
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Yu, Y. Y., P. A. Finke, H. B. Wu et Z. T. Guo. « Sensitivity analysis and calibration of a soil carbon model (SoilGen2) in two contrasting loess forest soils ». Geoscientific Model Development 6, no 1 (8 janvier 2013) : 29–44. http://dx.doi.org/10.5194/gmd-6-29-2013.
Texte intégralRésumé :
Abstract. To accurately estimate past terrestrial carbon pools is the key to understanding the global carbon cycle and its relationship with the climate system. SoilGen2 is a useful tool to obtain aspects of soil properties (including carbon content) by simulating soil formation processes; thus it offers an opportunity for both past soil carbon pool reconstruction and future carbon pool prediction. In order to apply it to various environmental conditions, parameters related to carbon cycle process in SoilGen2 are calibrated based on six soil pedons from two typical loess deposition regions (Belgium and China). Sensitivity analysis using the Morris method shows that decomposition rate of humus (kHUM), fraction of incoming plant material as leaf litter (frecto) and decomposition rate of resistant plant material (kRPM) are the three most sensitive parameters that would cause the greatest uncertainty in simulated change of soil organic carbon in both regions. According to the principle of minimizing the difference between simulated and measured organic carbon by comparing quality indices, the suited values of kHUM, (frecto and kRPM in the model are deduced step by step and validated for independent soil pedons. The difference of calibrated parameters between Belgium and China may be attributed to their different vegetation types and climate conditions. This calibrated model allows more accurate simulation of carbon change in the whole pedon and has potential for future modeling of carbon cycle over long timescales.
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McKEAGUE, J. A., C. TARNOCAI et H. A. LUTTMERDING. « EXISTING AND POSSIBLE NEW GLEYSOLIC ORDER CRITERIA APPLIED TO FIVE PEDONS FROM BRITISH COLUMBIA ». Canadian Journal of Soil Science 66, no 2 (1 mai 1986) : 323–36. http://dx.doi.org/10.4141/cjss86-033.
Texte intégralRésumé :
Use of the current criteria for distinguishing Gleysolic soils from gleyed intergrades to other soil classes resulted in the apparent misclassification of some soils in British Columbia. Pedologists of the area selected five pedons encompassing several degrees of expression of gley features. Current classification criteria based on soil color and possible new differentiating features based on chemical and micromorphological analyses were applied in considering the classification of the soils. Application of the current specific color criteria involving low chromas and prominent mottling result in the classification of three pedons in the Gleysolic order and two in gleyed subgroups of other orders. This classification was appropriate in the view of B.C. pedologists except for one Gleysolic pedon in which the water table is rarely within 1 m of the surface. Prior to drainage, however, the soil was probably saturated to the surface and under reducing conditions for prolonged periods each year. Thus, classification as a Gleysolic soil is appropriate as it probably reflects the prevailing conditions and processes during most of the period of soil genesis.Segregation of iron and manganese as nodules and coatings was most marked in the Gleysolic pedons. Walls of some voids were bleached due to depletion of iron oxides. Though study of thin sections, bulk chemical analysis and analysis of specific features by scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDXRA) were useful in providing information on soil properties, they did not indicate an improved basis for differentiating Gleysolic soils from others. The color criteria used to distinguish soils of the Gleysolic order do not necessarily reflect the current soil water regime, and they are not intended to do so. The current criteria resulted in the appropriate classification of the five soils. Key words: Gleying, reduction, iron, manganese, micromorphology, SEM-EDXRA
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Ukabiala, M. E., P. I. Ezeaku, J. Kolo, C. P. Umeugokwe et F. C. Okenmuo. « Characterization, classification, and suitability evaluation of soils formed in fluvial deposits within eastern part of Kogi State in Nigeria for rice and maize production ». Agro-Science 21, no 2 (22 juin 2022) : 100–110. http://dx.doi.org/10.4314/as.v21i2.12.
Texte intégralRésumé :
The impact of rice and maize production on food security in Nigeria cannot be over-emphasized. The aim of this research was to characterize, classify and evaluate the suitability of soils formed in fluvial deposits within eastern part of Kogi State in Nigeria for rice and maize production. This was supported by the fact that the knowledge of the characteristics and soil groups of fluvial deposits in soils is an integral part in soil suitability evaluation as well as management. Four (4) soil profile pits were sunk within the research area. The pedonswere located within the 19a mapping unit of the soil map of Nigeria which has the fluvial deposits. Pedons were adequately described as soil samples were collected from pedogenic horizons, and preserved in well-labelled polyethylene bags, transported to the Laboratory for analyses. The findings revealed that the soils were characterized by dominant gray (10YR4/1) and dark reddish gray (10R4/1) in the surface soils and dominance of various shades of gray in the subsurface soils. Most of the soil structures were single-grained and subangular blocky at the surface and subsurface soils respectively. The soil texture was sandy clay loam and sandy loam in the A horizons. The soil reaction showed mean values of 6.1 and 5.5 at the surface and subsurface horizons with base saturation highest (91%) at C1 horizon of 19a3 pedon. The pedons were classified as inceptisols, and were currently not suitable (N1) for rice cultivation but marginally suitable (S3) for maize cultivation.
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Ramamoorthy, P., et P. Christy Nirmala Mary. « Pedogenic characteristics of soil in Melur block, Madurai district, Tamil Nadu in India : A case study ». Journal of Applied and Natural Science 13, SI (20 juillet 2021) : 198–202. http://dx.doi.org/10.31018/jans.v13isi.2828.
Texte intégralRésumé :
Soil is an important source of human life and agricultural production. Studying on the pedon and its site characteristics pave the way for understanding the nature of soils and its utility. A study on pedological characterization of soils in Melur block, Madurai District (Tamil Nadu), was carried out during 2019-2020 using grid sampling with village map/cadastral maps. Soil mapping unit-based soil samples were collected in Chunampoor, Thuvarangulam, Poonjuthi and Veppapadupu and pedons were characterized as per the standard procedure. The results showed that soils were moderately deep to very deep in nature, ranging from 2.5 YR 3/6 to 10YR 4/6. The soil texture varied from sandy clay loam to sandy clay with weak to moderate sub-angular blocky structure. The consistency of soil varied from slightly hard to very hard when dry, very friable to firm when moist, slightly sticky to very sticky and slightly plastic to very plastic in wet condition. The crops viz., paddy, sugarcane, banana, groundnut and vegetables were very suitable for such type of soil of the Madurai district.
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Smeck, N. E., J. M. Bigham, W. F. Guertal et G. F. Hall. « Spatial distribution of lepidocrocite in a soil hydrosequence ». Clay Minerals 37, no 4 (décembre 2002) : 687–97. http://dx.doi.org/10.1180/0009855023740070.
Texte intégralRésumé :
AbstractThree terrace soils comprising a hydrosequence were examined to determine how the spatial distribution of lepidocrocite was related to depth and duration of saturation. Vertical relief was 1.0 m with well drained, moderately well drained, and somewhat poorly drained pedons spaced ∼60 m apart. All soils contained brittle, slowly-permeable subsoil horizons and were acidic with <35% base saturation throughout the upper sola. The well drained soil (Fragic Hapludult) had no morphological indicators of wetness within a depth of 180 cm, and water was perched above a brittle horizon at 82 cm for a total of only 41 days during the 3.4 year observation period. Nevertheless, trace amounts of lepidocrocite were detected in the subsoil. The moderately well drained soil (Typic Fragiudult) was saturated at a depth of 180 cm for 6% of the time, and water was perched on top of a fragipan at 74 cm for 13% of the time. Lepidocrocite was most abundant in this pedon and reached maximum concentrations below the fragipan in the capillary fringe of the regional water table (150–183 cm). The somewhat poorly drained member of the hydrosequence (Aeric Fragiaquult) was saturated at a depth of 180 cm for 96% of the observation period and also contained perched water above a fragipan for >90% of the time. Lepidocrocite occurred throughout this pedon but was most concentrated in fragipan horizons (86–135 cm) between the perched and regional zones of saturation. These horizons were saturated from 22 to 48% of the observation period. The results of this study suggest that lepidocrocite formation was favoured in horizons that were saturated for 5–50% of the time when soil temperatures exceeded 5°C.
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Peter, Kaananwii Dum, et Aigboghosa Samson Umweni. « Evaluation of land suitability for citrus cultivation in Khana Local Government Area of Rivers State, Southern Nigeria ». Ilmu Pertanian (Agricultural Science) 6, no 1 (6 janvier 2021) : 1. http://dx.doi.org/10.22146/ipas.60307.
Texte intégralRésumé :
Soils of Khana Local Government Area of Rivers State, Southern Nigeria were evaluated using semi detailed soil survey for citrus cultivation. The purpose of this research was to evaluate the suitability of soils of the study area for the cultivation of citrus. The total land area covers 49,631.54 ha and was delineated into eight mapping units based on the soil types. One pedon each was dug in each mapping unit and described using the FAO system. The nonparametric method of soil suitability evaluation was used. Four soil orders, majorly Inceptisols/Cambisols, Entosols/Arenosols, Ultisols/Acrisols, and Alfisols/Lixisols, were identified in the area. The results showed that land requirements/characteristics such as climate (mean annual rainfall), wetness (depth to water table) and fertility made the land marginally suitable (S3) to not suitable (N) for citrus cultivation across the eight pedons. The three limitations for citrus cultivation in the area are climate (annual rainfall), wetness (depth to the water table) and fertility (low status of NPK and pH). The land is potentially suitable for citrus cultivation but currently marginally and not suitable due to these three limitations.
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Kamal, Abha, et Abdullah Rashid. « The Nature of Iron Oxide Distribution in Some Calcareous and Gypsiferous Soils ». Tikrit Journal for Agricultural Sciences 20, no 2 (17 décembre 2022) : 107–19. http://dx.doi.org/10.25130/tjas.20.2.10.
Texte intégralRésumé :
The study area is located within two regions. The first site in Tikrit city (Tikrit University) represents gypsiferous soils and the second site represents calcareous soils in Erbil Governorate. Two pedons were chosen in Tikrit P1 (rainfed) and P2 (cultivated), and two other pedons in Erbil P3 (rainfed) and P4 ( cultivated) . Tikrit pedons showed presence of gypsum crystals of spindle and lenticular type with a length ranging between (0.2 -0.5) mm , the pores type of vughs and chamber, while the dominance of the planer and interconnected chamber pores in Erbil pedons. Iron oxides appeared in different forms of single discrete particles or Ferriargillans cutan especially in Erbil's pedons, The values of iron oxides varied, as the dominance of the total, free ,and the amorphous iron oxides in Erbil pedons were ranged between (8.77 -12.81), (8.17 - 10.30), (6.82 - 9.19) g.kg-1, respectively, compared with the iron oxides themselves for Tikrit pedons, which ranged between (2.98 - 5.39), (2.45 - 4.86), (1.19 - 2.67) g.kg-1, respectively. While the amorphous iron oxide values showed an increasing in the Tikrit pedons compared with Erbil pedons, as their values in Tikrit ranged between (1.26 - 2.19) g. kg -1 while in Erbil pedons ranged between (1.01 – 1.81) g. kg -1.
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Park, Won-Pyo, Kwan-Cheol Song, Bon-Jun Koo et Hae-Nam Hyun. « Distribution of Available Silicon of Volcanic Ash Soils in Jeju Island ». Applied and Environmental Soil Science 2019 (22 septembre 2019) : 1–10. http://dx.doi.org/10.1155/2019/2729694.
Texte intégralRésumé :
In soils, dissolved silicon (Si) is adsorbed onto soil particles or is leached into groundwater through the soil profile. Andisols may play an important role in contributing to high dissolved Si concentrations in groundwater on Jeju Island, Korea. In this study, we evaluated the available Si content that potentially affects groundwater composition and investigated the relationship between the available Si content and chemical properties of volcanic ash soil on Jeju Island. We used the 1 M sodium acetate buffer (pH 4.0) to extract the available Si. Selected chemical properties were determined for 290 topsoil samples collected from different land sites throughout Jeju Island, and we analyzed the available Si content in the typifying pedons of Jeju Island and mainland Korea. The available Si content in Jeju Island topsoils ranged from 75 to 150 mg·kg−1, and the available Si content of Andisols in both orchards and grasslands was significantly higher than that of non-Andisols. The available Si content was highly correlated with the amounts of oxalate extractable Si, Al, and Fe in Andisols and was negatively related to the Alp/Alo ratio. With increasing elevation, we detected a decrease in the available Si and allophane content in Andisols, whereas Al-humus complexes increased with increasing elevation. The ratio of available Si in the lowest subsoil/topsoil increased to a value of 6.0, indicating that large amounts of available Si are present in the subsoil. The available Si content in the lowest subsoil of Andisols on Jeju Island was 10 times higher than that in the typifying pedons of the Korean mainland. In contrast, there were no differences in the available Si content between the topsoil and the subsoil of the typifying pedon series of Jeju and mainland non-Andisols because of differences in pedogenic processes. Collectively, our findings indicate that weathering of Andisols on Jeju Island potentially affects the Si concentration in groundwater.
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Barbaccia, Pietro, Carmelo Dazzi, Elena Franciosi, Rosalia Di Gerlando, Luca Settanni et Giuseppe Lo Papa. « Microbiological Analysis and Metagenomic Profiling of the Bacterial Community of an Anthropogenic Soil Modified from Typic Haploxererts ». Land 11, no 5 (18 mai 2022) : 748. http://dx.doi.org/10.3390/land11050748.
Texte intégralRésumé :
This work aimed to characterize the microbial communities of an anthropogenic soil originating from application of pedotechniques to Vertisols in a Mediterranean environment. Bare soil profiles were sampled at three depths (0–10 cm, 10–30 cm, and 30–50 cm) and compared with the original soil not transformed at the same depths. The anthropogenic soils were characterized by a higher CaCO3 concentration (360–640 g/kg) than control soil (190–200 g/kg), while an opposite trend was registered for clay, where control soil showed a higher concentration (465 g/kg on average) than anthropogenic soil (355 g/kg on average). Organic carbon content was much higher in the untransformed soil. All samples were microbiologically investigated using a combined culture-dependent and -independent approach. Each pedon displayed a generally decreasing level with soil depth for the several microbial groups investigated; in particular, filamentous fungi were below the detection limit at 30–50 cm. To isolate bacteria actively involved in soil particle aggregation, colonies with mucoid appearance were differentiated at the strain level and genetically identified: the major groups were represented by Bacillus and Pseudomonas. MiSeq Illumina analysis identified Actinobacteria and Firmicutes as the main groups. A high microbial variability was found in all the three anthropogenic pedons and the microorganisms constitute a mature community.
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Nielsen, A. H., B. Elberling et M. Pejrup. « Soil development rates from an optically stimulated luminescence-dated beach ridge sequence in Northern Jutland, Denmark ». Canadian Journal of Soil Science 90, no 2 (1 mai 2010) : 295–307. http://dx.doi.org/10.4141/cjss09020.
Texte intégralRésumé :
Rates of podzolic soil development in sandy, temperate soils were quantified based on 14 soil pedons with five substrata from a beach ridge chronosequence near Jerup, Northern Denmark (57°N). Soil pH, organic carbon (C) as well as extractable iron (Fe) and aluminium (Al) were measured. The age of each pedon and soil stratum was measured by optically stimulated luminescence (OSL) dating and used to estimate soil development rates. Soils were divided into five groups from Typic Haplorthods and Entic Alorthods with a mean OSL age of 2965 ± 294 yr to Typic Quartzipsamments with a mean OSL age of 22 ± 11 yr. Acidification rates during the first 200 yr were ~1.9 pH units per 100 yr in the A horizons and C-sequestration rates were ~25 g C m-2 yr-1 (excluding litter accumulation). After ~1500 yr, the mineral soil C stocks stabilised around 13.0 ± 2.0 kg C m-2. Translocation rates of Al into B horizons were ~0.3 kg Al m-2 per 1000 yr, while translocation rates for Fe were scattered. Our study illustrates the potential of OSL dating in chronosequence studies to quantify soil development rates.Key words: Soil development rates, chronosequence, OSL-dating, C-sequestration rates and translocation rates
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Eshett, E. T., J. A. I. Omueti et A. S. R. Juo. « Soil properties and mineralogy in relation to land use on a sedimentary toposequence in south-eastern Nigeria ». Journal of Agricultural Science 112, no 3 (juin 1989) : 377–86. http://dx.doi.org/10.1017/s0021859600085828.
Texte intégralRésumé :
SummaryThe mineralogy of the clay fraction (<2 μm) of nine soil samples representing three physiographic positions of a toposequence in Ochon, south-eastern Nigeria, was determined by transmission electron microscopy and X-ray diffraction.Soils in the crest and middle slopes (pedons TE1 and TE2, respectively) of the toposequence, formed over fine-grained sandstone, were coarse-textured, well-drained and acidic and had low effective cation exchange capacity and percentage base saturation. Kaolinite, mica, quartz, goethite and gibbsite were the principal minerals identified in the clay fraction of these soils. Soils in the valley bottom (pedon TE3) formed over arenaceous shale were, on the other hand, fine-textured, poorly drained and weakly acidic with higher cation exchange capacity and percentage base saturation. Their clay fraction mineralogy was similar to that of the well-drained upland soils but additionally included feldspar and smectite/vermiculite mixed layer minerals.Mixed cropping of yam, cassava, maize and other annuals under traditional methods was carried out on the drier, well-drained crest and upper slopes while sole cropping of lowland rice occurred in the poorly drained, more fertile valley-bottom site. The valley-bottom soils show greater potential for improvement in agricultural productivity under good management than the upland soils.
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Hugelius, G., C. Tarnocai, G. Broll, J. G. Canadell, P. Kuhry et D. K. Swanson. « The Northern Circumpolar Soil Carbon Database : spatially distributed datasets of soil coverage and soil carbon storage in the northern permafrost regions ». Earth System Science Data 5, no 1 (15 janvier 2013) : 3–13. http://dx.doi.org/10.5194/essd-5-3-2013.
Texte intégralRésumé :
Abstract. High-latitude terrestrial ecosystems are key components in the global carbon (C) cycle. Estimates of global soil organic carbon (SOC), however, do not include updated estimates of SOC storage in permafrost-affected soils or representation of the unique pedogenic processes that affect these soils. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify the SOC stocks in the circumpolar permafrost region (18.7 × 106 km2). The NCSCD is a polygon-based digital database compiled from harmonized regional soil classification maps in which data on soil order coverage have been linked to pedon data (n = 1778) from the northern permafrost regions to calculate SOC content and mass. In addition, new gridded datasets at different spatial resolutions have been generated to facilitate research applications using the NCSCD (standard raster formats for use in geographic information systems and Network Common Data Form files common for applications in numerical models). This paper describes the compilation of the NCSCD spatial framework, the soil sampling and soil analytical procedures used to derive SOC content in pedons from North America and Eurasia and the formatting of the digital files that are available online. The potential applications and limitations of the NCSCD in spatial analyses are also discussed. The database has the doi:10.5879/ecds/00000001. An open access data portal with all the described GIS-datasets is available online at: http://www.bbcc.su.se/data/ncscd/.
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Hugelius, G., C. Tarnocai, G. Broll, J. G. Canadell, P. Kuhry et D. K. Swanson. « The Northern Circumpolar Soil Carbon Database : spatially distributed datasets of soil coverage and soil carbon storage in the northern permafrost regions ». Earth System Science Data Discussions 5, no 2 (13 août 2012) : 707–33. http://dx.doi.org/10.5194/essdd-5-707-2012.
Texte intégralRésumé :
Abstract. High latitude terrestrial ecosystems are key components in the global carbon (C) cycle. Estimates of global soil organic carbon (SOC), however, do not include updated estimates of SOC storage in permafrost-affected soils or representation of the unique pedogenic processes that affect these soils. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify the SOC stocks in the circumpolar permafrost region (18.7 × 106 km2). The NCSCD is a polygon-based digital database compiled from harmonized regional soil classification maps in which data on soil order coverage has been linked to pedon data (n = 1647) from the northern permafrost regions to calculate SOC content and mass. In addition, new gridded datasets at different spatial resolutions have been generated to facilitate research applications using the NCSCD (standard raster formats for use in Geographic Information Systems and Network Common Data Form files common for applications in numerical models). This paper describes the compilation of the NCSCD spatial framework, the soil sampling and soil analyses procedures used to derive SOC content in pedons from North America and Eurasia and the formatting of the digital files that are available online. The potential applications and limitations of the NCSCD in spatial analyses are also discussed. The database has the doi:10.5879/ecds/00000001. An open access data-portal with all the described GIS-datasets is available online at: http://dev1.geo.su.se/bbcc/dev/ncscd/.
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Yu, Y. Y., P. A. Finke, H. B. Wu et Z. T. Guo. « Sensitivity analysis and calibration of a soil carbon model (SoilGen2) in two contrasting loess forest soils ». Geoscientific Model Development Discussions 5, no 3 (16 juillet 2012) : 1817–49. http://dx.doi.org/10.5194/gmdd-5-1817-2012.
Texte intégralRésumé :
Abstract. To accurately estimate past terrestrial carbon pools is the key to understand the global carbon cycle and its relationship with the climate system. SoilGen2 is a useful tool to obtain aspects of soil properties (including carbon content) by simulating soil formation processes; thus it offers an opportunity for past soil carbon pool reconstruction. In order to apply it to various environmental conditions, parameters related to carbon cycle process in SoilGen2 are calibrated based on 6 soil pedons from two typical loess deposition regions (Belgium and China). Sensitivity analysis using Morris' method shows that decomposition rate of humus (kHUM), fraction of incoming plant material as leaf litter (frecto) and decomposition rate of resistant plant material (kRPM) are 3 most sensitive parameters that would cause the greatest uncertainty in simulated change of soil organic carbon in both regions. According to the principle of minimizing the difference between simulated and measured organic carbon by comparing quality indices, the suited values of kHUM, frecto and kRPM in the model are deduced step by step. The difference of calibrated parameters between Belgium and China may be attributed to their different vegetation types and climate conditions. This calibrated model is improved for better simulation of carbon change in the whole pedon and has potential for future modeling of carbon cycle in paleosols.
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Dawood, Abdulameer, Dakel Nedewi et Hussain Hussain. « Characterization , Classification and Prediction of Soil Map Units Boundaries by Using Remote Sensing and GIS in Bahar Al-Najaf / Iraq ». Journal of Kufa-Physics 9, no 2 (20 juillet 2022) : 27–46. http://dx.doi.org/10.31257/2018/jkp/2017/v9.i2.9432.
Texte intégralRésumé :
The study area is located in the west of the Al-Najaf Al-Ashraf city center, It is bounded by 32o 8’ 8” - 31o 39’ 16” N and 44o 3’ 15” – 43o 4’ 11” E, It covers an area of (1970 ) Km2 lying within the land of Al-Najaf sea. The study relied on Satellite Image for Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) which captured on 07/13/2014 from the USGS site, The study area was truncated by using ERDAS package, and followed by choose the mix of False color Composite RGB (753) to be the best being a specialist to study the soil and minerals. Some improvements have been made (radiation and spectral and spatial) and Unsupervised classification as well as the use of Earth indicators such as the heterogeneity of the characteristics of field perspective on the ground such as soil Color, texture and natural plants in addition to topographical in determining the movement paths to select 16 Pedon sites . The results showed a variation in spectral reflectivity values both between studied pidons within the same spectral range or between the spectral bands used in this study, reflecting the state of the contrast between the characteristics of soils for studied pidons as well as the variation in susceptibility sensor spectral bands among them. The reflectance of B2 , B3 bands were low comparing with others in all pedons sites, this mean that ability of soil materials to absorb them were more than the rest, for this their sensitivity appear low. On other hand, B5 , B6 bands show higher reflectivity than others of OLI sensor in all pedons sites. As the NDVI index values were 0.1 or less, this mean that most of study areas were bare soils or covered with low vegetation. Thermal Infrared bands B10 , B11 show the highest values of DN comparing with others, this identifying that soil surface salts were thermal incentive. Spectral bands appear positive correlation with sand and clay grains but negative with Silt grains and bulk density. Electrical conductivity and gypsum appear negative correlation with all bands and studied spectral indices except B2,B3 bands were positive. Calcite shows positive correlation with all spectral bands and indices, but negative with B2 and NDWI index.
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Dyck, M. F., et R. G. Kachanoski. « Scale-dependent covariance of soil physical properties above and below a soil horizon interface : Pedogenic versus anthropogenic influences on total porosity ». Canadian Journal of Soil Science 91, no 2 (mai 2011) : 149–59. http://dx.doi.org/10.4141/cjss10078.
Texte intégralRésumé :
Dyck, M. F. and Kachanoski, R. G. 2011. Scale-dependent covariance of soil physical properties above and below a soil horizon interface: Pedogenic versus anthropogenic influences on total porosity. Can. J. Soil Sci. 91: 149–159. The basic unit of soil – the pedon – is described as the minimum, three-dimensional unit of soil representative of the variability of soil horizon dimensions and morphology. Pedogenic processes responsible for soil horizon and soil profile formation are primarily hydrologic in nature. The spatially variable distribution of soil horizons (i.e., the variation among pedons within catenae or landscapes) is likely a reflection of the inherent variability of the soil parent material and the spatial variability of hydrological/pedogenic processes. This paper explores the spatial variability and spatially scale-dependent covariance between a basic soil property (porosity) above and below an A/B horizon interface under adjacent disturbed (cultivated) and undisturbed (forested) conditions. A combination of scale-dependent variance and Fourier-domain spectral analysis shows that the scale-dependent covariance of A and B horizon porosity varies significantly between the cultivated and forested sampling transects. The majority of these observed differences between the scale-dependent covariance of A and B horizon porosity under contrasting land uses is attributed to tillage. These results suggest that anthropogenic activities such as tillage may not only alter the surface horizons, but the nature of the spatial covariance between surface and underlying horizons which likely influences current soil hydrological processes.
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Khaled, Khaled Anwer, et Yusof Hasan Yusof. « Development of B horizon in relation to Morphological characterization and soil uniformity of some soil of northern of Iraq ». Tikrit Journal for Agricultural Sciences 22, no 4 (31 décembre 2022) : 62–72. http://dx.doi.org/10.25130/tjas.22.4.9.
Texte intégralRésumé :
The aim of the study to estimate soil uniformity and development using B horizon, Three pedons were selected within Nineveh Governorate (Rashedyia, Talafar, and Telkaif), The morphological description was carried out according to the principles followed in soil survey staff, (2014), then each pedon was divided into depths and soil samples were taken from these depths to be transferred in to laboratory for physical and chemical analysis, also some of sand particles separated by different size of sieves. The results showed an increase in sand particles values downward to the third depth and then decreased again in the fourth depth in most study sites. A parallel curve was reached at Talafar 's location within the deepest except for the fifth depth, which showed an intersection in the size of the very coarse sand (VCS), which gave a lower proportion of the rest of the depths, due to the fact that the sampling was taken advantage of the grazing area and there was no equal movement of that size between the depths, albeit slight. The values of the ratio of fine sand to the total sand showed that they were relatively lower than the values of the ratio of fine sand to coarse sand for all locations, its rates ranged (0.41 - 0.83), the standard deviation values from the arithmetic mean were less than 21% in all locations except the surface layer at Telkaif, which amounted to (30.61%).
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Gentsch, N., R. Mikutta, R. J. E. Alves, J. Barta, P. Čapek, A. Gittel, G. Hugelius et al. « Storage and transformation of organic matter fractions in cryoturbated permafrost soils across the Siberian Arctic ». Biogeosciences 12, no 14 (30 juillet 2015) : 4525–42. http://dx.doi.org/10.5194/bg-12-4525-2015.
Texte intégralRésumé :
Abstract. In permafrost soils, the temperature regime and the resulting cryogenic processes are important determinants of the storage of organic carbon (OC) and its small-scale spatial variability. For cryoturbated soils, there is a lack of research assessing pedon-scale heterogeneity in OC stocks and the transformation of functionally different organic matter (OM) fractions, such as particulate and mineral-associated OM. Therefore, pedons of 28 Turbels were sampled in 5 m wide soil trenches across the Siberian Arctic to calculate OC and total nitrogen (TN) stocks based on digital profile mapping. Density fractionation of soil samples was performed to distinguish between particulate OM (light fraction, LF, < 1.6 g cm−3), mineral associated OM (heavy fraction, HF, > 1.6 g cm−3), and a mobilizable dissolved pool (mobilizable fraction, MoF). Across all investigated soil profiles, the total OC storage was 20.2 ± 8.0 kg m−2 (mean ± SD) to 100 cm soil depth. Fifty-four percent of this OC was located in the horizons of the active layer (annual summer thawing layer), showing evidence of cryoturbation, and another 35 % was present in the upper permafrost. The HF-OC dominated the overall OC stocks (55 %), followed by LF-OC (19 % in mineral and 13 % in organic horizons). During fractionation, approximately 13 % of the OC was released as MoF, which likely represents a readily bioavailable OM pool. Cryogenic activity in combination with cold and wet conditions was the principle mechanism through which large OC stocks were sequestered in the subsoil (16.4 ± 8.1 kg m−2; all mineral B, C, and permafrost horizons). Approximately 22 % of the subsoil OC stock can be attributed to LF material subducted by cryoturbation, whereas migration of soluble OM along freezing gradients appeared to be the principle source of the dominant HF (63 %) in the subsoil. Despite the unfavourable abiotic conditions, low C / N ratios and high δ13C values indicated substantial microbial OM transformation in the subsoil, but this was not reflected in altered LF and HF pool sizes. Partial least-squares regression analyses suggest that OC accumulates in the HF fraction due to co-precipitation with multivalent cations (Al, Fe) and association with poorly crystalline iron oxides and clay minerals. Our data show that, across all permafrost pedons, the mineral-associated OM represents the dominant OM fraction, suggesting that the HF-OC is the OM pool in permafrost soils on which changing soil conditions will have the largest impact.
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Mahabadi, Nafiseh Yaghmaeian, et Shahram Mahmoud Soltani. « Applicability of Fuzzy and Fuzzy Analytic Hierarchy Process (Fuzzy AHP) Methods to Determine the Optimum Soil Depth in Land Suitability Evaluation for Irrigated Rice ». Polish Journal of Soil Science 54, no 1 (29 juin 2021) : 103. http://dx.doi.org/10.17951/pjss.2021.54.1.103-122.
Texte intégralRésumé :
<p>The conventional Boolean logic models of land suitability assessment disregard the continuity concepts of the soil and landscape which might cause inaccurate evaluation and classification. To overcome this uncertainty and consequent constraints, the fuzzy set theories were introduced. Therefore, the current study was undertaken to estimate the optimum soil depth that is used in land suitability evaluation for irrigated rice through the fuzzy sets theory and analytic hierarchy process (fuzzy AHP) in Guilan Province, Iran. The square root and quantitative land suitability evaluation methods were employed to calculate traditional land suitability indices (for depths, 0-25, 0-50, 0-75, and 0-100 cm). Also, fuzzy and fuzzy AHP methods were used to explore new land indices. The Sarma similarity indices were used to compare the results of traditional and fuzzy methods for different soil depths. The results showed that the compatibility percentage between the representative pedons (0-100 cm) and the findings of this research (0-50 and 0-75 cm) were remarkable. Furthermore, the highest compatibility percentage of land suitability class was related to the comparison of these two former depths and 0 to 100 cm depths in each of the two used fuzzy methods. Besides, except for 0-25 cm depths, actual yield revealed a significant and positive correlation with the rest three soil pedon depths. These findings show that considering 0 to 50 cm soil depth might be a relevant alternative as the optimal depth to evaluate land suitability for rice in paddy fields in the Guilan rice-growing area. </p>
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Shaalan Jarallah, Raid, et Bahaa Hussein Fadel Al-mayaly. « Effects of Soil Depth and Rivers Slopon Total Boron Content in Some of The Iraqi Provinces ». Al-Qadisiyah Journal For Agriculture Sciences (QJAS) (P-ISSN : 2077-5822 , E-ISSN : 2617-1479) 8, no 2 (1 décembre 2018) : 22–40. http://dx.doi.org/10.33794/qjas.vol8.iss2.57.
Texte intégralRésumé :
Aiming to study effects of soil depth and rivers slop on total boron concentration inMiddle Euphrates River Reion that represent in the sedimentary plain, soil pedon samples of cultivated territory that adjacent to rivers were taken. Theseregions are located in provinces of Karbala, Babylon, Najaf, Diwaniyah, and Al-Muthana. Ten soil pedon were taken of soils that adjacent to the main Euphrates River, the Al-Hilaa, and the AL-Daghara Rivers in these provinces. Soil pedon of soils that on the banks or close to the main Euphrates River were taken of counties of Twarije, Kufa, Gamas, and Al-Samawa. In the same way, soil pedon of Missaib, Hashmiah, Diwaniyah, and Rumitha are adjacent to the Hilla River and soil pedon of Al-Daghara and Affak belongs to the area of Al-Daghara River. Results show a reduction in total boron concentration for all of the tested soil pedon directly related with the depth. Aggregate boron concentration values are the highest at the surface layer and reduce as going depth except for soils of Al-Samawa and Al-Rumitha. Total boron concentration values are fluctuated between 1.033 mg. kg-1 and 14.658 mg. kg-1 in all of the studied soils. the results showed too the total boron values are not conducted with the tourmaline mineral percent in all sites