Typic Udorthents Research Articles

Effects of biochar and wood ash amendments in the soil-water-plant environment of two temperate forest plantations

Forest biomass is considered an alternative to fossil fuels in energy production, as part of global strategies for climate change mitigation. Application of by-products such as wood ash (WA) and biochar (BC) to soil could replace the nutrients removed by tree harvesting and could also increase soil carbon stocks. However, the extent to which these amendments can provide benefits depends on how the by-products interact with the soil-water-plant system. We studied the short-term responses of WA and BC application in two different mineral soil-water-plant systems in temperate forests: A. Typic Udorthent (TU) with mature Pinus radiata; B. Typic Dystrudept (TD) with young Quercus pyrenaica, to test the following hypotheses: (1) the application of WA and BC will increase nutrient uptake by plants, but (2) these products could induce toxicity in the soil-water-plant system, and (3) in case of no toxicity, plant biomass growth in these temperate forest soils will increase due to increased plant nutrient uptake. Biochar was applied at rates of 3.5, 10, and 20 Mg ha–1 and WA at rates of 1.5, 4.5, and 9 Mg ha–1 (calcium equivalent). A nitrogen enriched treatment was applied with the intermediate doses. Ecotoxicity testing indicated that WA and BC were not toxic, although Ni uptake increased in biomass of the TU after BC + N application. BC increased SOC stocks of both sites, depending on treatment. In TD BC increased K uptake by plants, but did not increase biomass. In summary, this study shows that the application of BC and WA had different effects on the soil -water-plant system in two different forest soils. This difference was attributed to (i) the soil characteristics, (ii) the application rates and (iii) whether or not nitrogen was applied. Long-term field experiments are required to test the performance and potential toxicity of these by-products as soil enhancers.

Analysis of soil characteristics and classification from order to family category in Makale District

Makale, with hilly and mountainous areas in Tana Toraja Regency, provides high agricultural productivity so that soil as a medium for growing plants is one aspect that needs attention. Minerals influence the soil’s physical and chemical properties because they are the main constituent of the soil, so that the characteristics and types of soil will vary. This study aimed to determine the type of soil based on toposequences and catena sequences from order to family category in Makale district, Tana Toraja regency, according to soil taxonomy in 2014. The method used was toposequences and catena sequences in one transect. Soil physical and chemical analysis including; soil color, texture, bulk density, C-organic, CEC, K, Na, Ca, and Mg. Analysis of soil minerals using the Fourier Transform InfraRed (FTIR) method. The results showed that the soil types found in the Makale district were Lithic Udorthents, Typic Udorthents, Typic Haplohumults, Oxic Dystrudepts, Typic Eutrudepts, and Dystric Eutrudepts. The dominant clay minerals are montmorillonite in profiles 1 and 2, kaolinite in profiles 3 and 5, chlorite and quartz in profiles 4 and 6.

Indeks Produktivitas Tanah Berbasis Soil Taxonomy dan Korelasinya Dengan Produktivitas Kopi pada Beberapa Ordo Tanah

Penilaian indeks produktivitas (IP) berbasis taksonomi tanah merupakan salah satu model yang sederhana dan bersifat relatif tetap, sehingga model ini sangat menjanjikan untuk kepentingan praktis dalam skala regional, namun sampai saat ini pengujian-pengujian lapangan menyangkut keakuratan model tersebut untuk tanaman tahunan masih belum pernah dilakukan. Penelitian ini bertujuan untuk mengevaluasi keakuratan aplikasi model IP berbasis taksonomi tanah untuk tanaman kopi, yang dimanifestasikan dalam bentuk tingkat keeratan hubungan antara IP dengan produktivitas kopi robusta. Penelitian dilaksanakan di enam lokasi perkebunan kopi yang berada di wilayah Kabupaten Jember dan Banyuwangi, yaitu kebun kopi Sidomulyo (kebun rakyat), Rayap-1 dan Rayap-2, Tretes, Kampung Tengah, dan kebun Gumitir (kebun PTPN XII). Di setiap lokasi dibuat satu profil tanah pewakil berukuran 1 x 1,5 m dengan kedalaman 1 m untuk keperluan pencanderaan morfologi tanah dan analisis sifat-sifat fisika dan kimia setiap lapisan tanah. Analisis sifat-sifat tanah meliputi tekstur tanah, pH (H2O) dan pH (KCl), C-Organik tanah, kapasitas tukar kation (KTK), dan kejenuhan basa. Berdasarkan hasil pencanderaan dan sifat-sifat fisika kimia di enam lokasi penelitian tersebut, diperoleh empat jenis tanah tingkat subgrup, yaitu Typic Udorthents untuk kebun Sidomulyo (IP = 6); Typic Dystrudepts untuk kebun Rayap-2 (IP = 7); Typic Hapludalfs untuk kebun Rayap-1, Kampung Tengah dan Tretes (IP = 10);; serta Typic Eutrudepts untuk kebun Gumitir (IP = 11). Hasil penelitian ini menunjukkan bahwa IP mempunyai hubungan positif sangat kuat dengan produktivitas kopi robusta (r = 0,84) dalam bentuk model linier sederhana, semakin tinggi IP produktivitas kopi robusta semakin meningkat.

Efecto del encalado en el uso eficiente de macronutrientes para cacao (Theobroma cacao L.) en la Amazonia colombiana

En la Amazonia colombiana, el cultivo de cacao (Theobroma cacao L.) presenta bajo rendimiento debido a que la alta acidez del suelo limita el uso eficiente de nutrientes. Por lo tanto, esta investigación evalúa el efecto del encalamiento y la fertilización en un suelo ácido (Typic Udorthents) de la Amazonia colombiana sobre el uso eficiente de nutrientes (uen), en términos de la eficiencia agronómica (ea) y la eficiencia de recuperación del fertilizante (erf) para nitrógeno (N), fósforo (P) y potasio (K), y cuatro clones universales de cacao fino de sabor y aroma. Se utilizó un diseño en bloques completos al azar con arreglo factorial, siendo el factor A cuatro clones (a1: ICS-1, a2: CCN-51, a3: ICS-39, y a4: TSH-565) y el factor B cuatro niveles de fertilidad (b1: control absoluto; b2: suelo 90 días después de encalado (dde); b3: control absoluto más N - P - K, hasta alcanzar los requerimientos del cultivo; b4: b2 más N - P - K, hasta alcanzar los requerimientos del cultivo). Los resultados muestran que el encalado y la fertilización afectaron el uen y el rendimiento; mientras tanto, el más bajo rendimiento se presentó en b1 para todos los clones, sugiriendo que la fertilidad del suelo natural no es suficiente para el desarrollo del cultivo de cacao; además, el clon CCN-51 mostró mayor habilidad en el uso de nutrientes que los restantes clones. En este sentido, los cuatro clones respondieron de forma diferencial de acuerdo con la ea y la erf, evidenciando la influencia del genotipo y de las condiciones edafoclimáticas de la zona, así como las preferencias específicas de pH y nutrientes para cada clon.

Effect of Topography on Characteristics, Fertility Status and Classification of the Soils of Almora District in Uttarakhand

Topographic position is one of the most dominant factors that govern soil development in the hilly areas. Ten soil profiles representing different landform units i.e. hill top, side slope, broad valley and narrow valley terraces were chosen to investigate the soil morphological, physical and chemical characteristics and their relationships with topography in Almora district of Uttarakhand. Soil properties varied remarkably among the studied profiles. The soils were moderately shallow to very deep in depth (32–160 cm), nonsaline (EC 0.03–0.45 dS m−1), acidic in nature (pH 5.1–6.6), low to high in organic carbon (OC) (0.03–2.91%) with low to moderate CEC [1.6–19.4 cmol(p+)kg−1]. Base saturation ranged from 45.9 to 75.1% in which calcium (Ca2+) and magnesium (Mg2+) were the dominant cations on exchangeable sites followed by potassium (K+) and sodium (Na+). The studied soils were dominated by silt fraction followed by clay, except in Dhamas (P4), Dhaili (P5) and Kosi (P10) which showed high sand content. Hill top profiles showed the highest OC. The upper soil layers of hill top and broad valley terrace profiles showed higher availability of soil macronutrients, whereas micronutrients were higher than agronomic critical limits in all profiles. Three soil profiles were classified as Entisols and keyed out as Typic Udifluvents (Kosi), Lithic Udorthents (Dhamas) and Typic Udorthents (Dhaili). Majkhali (P7) soils were placed under Inceptisol soil order and were classified as Dystric Eutrudepts. The remaining soils were placed under Alfisol soil order and keyed out as Hapludalf at great group level. Among the Alfisols, Someshwar (P9) was classified as Oxyaquick Hapludalfs, Sitlakhet (P1) was classified as Ultic Hapludalfs, Salla Routela (P2) and Chaubattia (P3) were classified as Mollic Hapludalfs, while Kausani (P6) and Hawalbagh (P8) soils were keyed out as Typic Hapludalfs. The soils in Almora district of Uttarakhand exhibited wide variations with topographic positions and proper soil management will help in maintaining sustainable production of this area.

Soil morphogenesis diversity at the southern flank of Merapi Volcano, Indonesia five years post-eruption

This study aims to find out the soil morphology diversity at the southern flank of Mt.Merapi Yogyakarta, Indonesia. The field research was conducted using purposive sampling method where each site of geomorphological unit as representing of the cone, upper, middle and lower slopes of Mt.Merapi. Poligenesis of the soil morphology was observed at pedon P1 with composition of the upper and buried soil was Typic Hapludands-Typic Hapludands, P3 (Andic Eutrudepts-Vitrandic Udorthents), P4 (Vitrandic Udorthents -Typic Hapludands), and P5 (Andic Eutrudepts-Andic Eutrudepts). Whereas the monogenesis of the soil morphology was observed at pedon P2, P6, P7 and P8 with subgroups of Typic hapludands, Andic Eutrudepts, Andic Dystrodepts and Typic Udorthents, respectively. Soil morphogenesis diversity (polygenesis) shown by the presence of a pedon having more than one soil profile was not a limiting factor for crop roots growth, so the agro-ecosystem recovery process was relatively fast.

Degree of phosphate saturation in highly weathered tropical soils

The degree of phosphate saturation (DPS) is an indicator for P-saturation, which is of assistance to the prediction of P losses and potential eutrophication of surface water. The scaling factor (α) estimates the adsorption capacity of the soil and is used to calculate the DPS. In soils from temperate regions, the value of α = 0.5 is widely used. However, using just a single value for α may fail to estimate the adsorption capacity correctly for all soils. In this study, the aims were (i) to calculate the scaling factor α and the DPS of highly weathered tropical soils with different chemical, physical and mineralogical properties in order to predict P losses; and (ii) to identify which soil properties are related to P adsorption. The scaling factor α and the DPS were calculated at 1, 3, 7, 21, 42 and 84 days (d), the highest one in recognition of the long-term kinetics of sorption. The values ​​of α increased as the contact period increased. Lower DPS values were obtained in soils with high P adsorption capacity whereas the highest DPS values were obtained in soils with a lower adsorption capacity. Out of ten Oxisols studied, six of them had an α higher than 1. Contents of clay, organic carbon (C) and poorly crystalline (Alox) and crystalline (“free”) Al oxides were the properties that best correlated with P adsorption. For the Oxisols, the clay content, poorly crystalline together with crystalline Fe and Al oxides represented the main components related to P adsorption. The highest DPS (31%) was found in Typic Udorthent. The content of poorly crystalline oxides was not suitable for the scaling factor α for most Oxisols, and only the Typic Udorthent exceeded the critical threshold of 23%, and is thus more susceptible to loss of P.

Relación entre el pH y la disponibilidad de nutrientes para cacao en un entisol de la Amazonia colombiana

El encalado es una práctica común en el manejo de suelos ácidos, sin embargo, la información sobre encalado en suelos cacaoteros de la Amazonia colombiana es precaria. Se construyeron curvas de incubación en un Typic Udorthents fuertemente ácido cultivado con cacao (Theobroma cacao L., Malvaceae), para lo cual se utilizaron dosis crecientes (0 - 1 - 3 - 5 - 7 - 9 - 11 Mg/ha) de cal dolomita (CaMg(CO3)2) y carbonato de calcio (CaCO3), con el fin de conocer el tipo y cantidad de material encalante (ME) de mejor reactividad y el que más favorece los cambios en la acidez: pH, Al3+, H+ y acidez total. Se construyeron los modelos para estimar la dosis de ME necesaria para llevar el suelo al pH deseado (≥5,5). Posteriormente se encaló el suelo en condiciones de campo y se evaluó el efecto en pH, Al3+, Al en solución (Alsol), saturación de aluminio (SAI), capacidad de intercambio catiónico (CIC) y la disponibilidad de N, P, K, Ca, Mg, Zn, Cu, B, Fe y Mn. Los resultados muestran que la mayor reacción de los materiales encalantes en estos suelos se presenta después de 60 días. Aplicaciones de 7 Mg/ha permitieron elevar el pH de 5,5 a 6,0 y disminuir los niveles de Al y Fe, cambios que mejoraron la CIC y la disponibilidad de nutrientes para cacao (Ca, Mg, P, Zn) sin afectar otros nutrientes como N y K.

Soil biological properties in multistrata successional agroforestry systems and in natural regeneration

The diversity of cultivated plants in the agroforestry systems can create conditions to maintain the vital edaphic processes similar to natural regeneration areas. We studied agroforestry systems with five (AF5) and ten years (AF10) of age in comparison with natural regeneration areas for 10 years (NR) in the Atlantic Forest Biome in an area of environmental fragility. The microbial biomass carbon (MB-C), soil basal respiration (BResp), metabolic quotient (q-CO2) and microbial quotient (q-mic) were evaluated in the entire profile of a Typic Udorthents, obtaining stratified data in the 0–2.5; 2.5–5; 5–10; 10–15; 15–30; 30–45 and 45–60 cm layers. The NR area had the highest MB-C (866 mg C kg−1 soil) and BResp (5 mg C-CO2 kg−1 soil h−1) in the 0–2.5 cm layer in relation to the AF5 (686 mg C kg−1 soil; 4 mg C-CO2 kg−1 soil h−1) and AF10 (478 mg C kg−1 soil; 4 mg C-CO2 kg−1 soil h−1). However, the ratios did not differ among treatments, presenting average values in the profile of 7 mg C-CO2 g−1 MB-C h−1 for q-CO2 and 1.6 % for q-mic, demonstrating vital process similarity between systems. The phytosociological characteristics that interfere with the microbiological attributes were the plant species richness (0–2.5 cm) and plant diversity (2.5–5 cm). The epiedaphic fauna active in the litter was also assessed by pitfall traps and the average number of individuals per trap (238 for NR, 281 for AF5, 299 for AF10), the order richness (15 for NR; 14 for AF5, 13 for AF10) and relative frequencies did not differ among treatments, confirming that agroforests are in an ecosystem self-regulation condition function similar to natural regeneration, even with the removal of food products and income generation for the farmers.

Improvement of productivity and polysaccharide-protein complex in Agaricus blazei

The objective of this work was to assess the productivity and polysaccharide-protein complex content of Agaricus blazei on rice straw medium, in comparison to conventional sawdust, using four casing soils. The A. blazei strain used was BCRC36814T, purchased from the Food Industry Research and Development Institute, Hsin-Chu, Taiwan. The two media were evaluated as to A. blazei productivity, harvesting time, and production costs. The experimental design used was a randomized complete block, with four replicates. Three local casing soils - Typic Paleudult (CCe), Typic Udorthent (Tq) and Oxyaquic Paleudult (TSp) - were compared to imported peat soil (PS, Saprists, Histosols), used as the control. The productivity of A. blazei using Tq and TSp soil was significantly higher. The TSp casing treatment resulted in earlier harvest by at least 14 to 27 days, when compared to the other treatments. The polysaccharide content in CCe (13.2%) and Tq soils (13.2%) did not differ significantly from the PS (13.4%) and TSp (10.6%) treatments. Local casing soils decreased the production costs of A. blazei cultivation. Composted rice straw can substitute sawdust as the culture medium for A. blazei production with increased yield.

Morphological, chemical and mineralogical characterization of developing soils and their management in the western Siwalik Himalayas

The western Siwalik Himalayas of India experienced the last climate shift 3500 years ago and the soils have been marked by rigorous human activities for a few centuries. An attempt was made to investigate the interactions between soil-forming factors and processes in soil development in relation to land forms and climate change. The hallmark of the soils is the considerable heterogeneity in solum and regolith thickness, horizon boundaries, structural development in surface soils, pH, electrical conductivity and soil mineralogy, irrespective of landscape form and position. A remarkable feature of the soils is the development of deep argillic horizons, or B horizons, in certain landscape positions. The minerals identified were quartz, micas and feldspars in the sand and silt fractions. Illite, kaolinite, vermiculite, smectite and chlorite were present in the clay fractions. Soils under forest vegetation and those recently brought under cultivation belong to Typic Hapludalfs. Soils cultivated over centuries, however, failed to qualify as Alfisols and were classified as Typic/Dystric Eutrudepts. The eroded barren soils were similarly classified as Typic Udorthents. All the soils were low to medium in available nitrogen and phosphorus. The use of nitrogen and phosphorus fertilizer is therefore needed to ameliorate nutrient deficiency and boost crop production. Because of the presence of appreciable amounts of potassium-bearing minerals, soils are likely to be non-responsive to potassium application. The soils of the Dala series (Typic Hapludalfs) are located on moderate hill slopes and thus soil erosion is less severe than for the Mansu series (Typic Udorthent). In the Chamror and Dhar series (Typic/Dystric Eutrudepts) soil erosion is not a serious problem because of terracing and the finer texture of the soils. Crops can thus be grown on profile-stored moisture during dry periods and limited grazing may be permitted.

Soil structure and flow rate-controlled molybdate, arsenate and chromium(III) transport through field columns

Preferential flow in soil causes rapid movement of chemicals and contamination at the tile-line level. Soil structure and flow rate effect on transport velocity of MoO 4 2−, H 2AsO 4 −1, and Cr + 3 was assessed for three soils differing in vadose structure. Triplicate, 50 cm long, 35 cm diameter field soil columns of Lamellic Hapludalf, Typic Udorthent, Typic Hapludalf from southwestern Germany were obtained. The metals solute prepared in 3.5 mM LiCl was applied as pulse, and flushed with synthetic rainwater of pH 5.5 at constant flow rates generated by + 10, −10, and −40 mm water heads at the column surface. The tracers' breakthrough data were fitted to a convective–dispersive flow equation with mobile and immobile soil water partition. Additionally, blue dye was rained on site, and X-ray tomography of one representative column from each soil was carried out to identify preferential flow paths in the field soils. Lamellic Hapludalf (sandy loam) had a dominantly massive structure, and blue dye flowed as vertical fingers. Typic Udorthent (silt loam) had well-connected macropores, and dye moved as macropore flow with radial diffusion. Typic Hapludalf (silty clay) had well-connected pores throughout the profile, and dye moved the deepest with smallest dyed area. Chloride moved sampling 0.30 to 0.33 fraction of porosity in the massive soil irrespective of flow rate; and depending on flow rate, it moved through only 0.05 to 0.15 fraction of porosity in the structured silt loam/silty clay soil columns. MoO 4 2−, H 2AsO 4 −1 and Cr + 3 leached as fast as Cl −1 under ponded flow and with large retardation under unsaturated flow suggesting macropore flow of the adsorbing solute in the well-structured soils. The massive soil effectively retained H 2AsO 4 −1 and Cr + 3 but allowed MoO 4 −2 to leach at all the flow rates. Retardations of the absorbing tracers were in the order of Cr + 3 > H 2AsO 4 −1 > MoO 4 −2 > Li + 1 . Depending on soil structure, the effective porosity and retardation increased, and dispersion decreased with reduced flow rate. The study concludes that strongly graded, coarse to medium angular/prismatic soil peds allow adsorbing solute to leach at reduced flow rate, and the field description of soil structure helps discern areas where preferential flow can potentially cause subsoil contamination.

Characterization and classification of soils along a typical Hillslope in Afikpo area of Ebonyi state, Nigeria

Three pedons representing soils on the summit to shoulder (Pedon 1), backslope to footslope (Pedon 2) and toeslope (Pedon 3) positions along a typical hillslope in Afikpo area of Ebonyi State of Nigeria were studied regarding their morphological, physico-chemical and mineralogical properties. The soils were also classified according to the criteria of the USDA Soil Taxonomy and the FAO World Reference Base for Soil Resources. Soils of Pedons 1 & 2 occur on very strongly sloping, severely eroded uplands and are derived from ferruginous, feldspathic sandstone with shale intercalations. The soils in the toeslope position, occur on extensive, nearly level plains which are seasonally waterlogged with colluvio-alluvial sediments constituting the parent material. Irrespective of slope position, all the soils are very strongly acidic with a narrow pH range of 4.6 – 5. 1 and an average exch. Al3+ content of 3.77cmol kg-1 in all the horizons studied. Levels of organic C, total N, avail. P, exch. Ca, Mg, and K, range from being very low in Pedon 1, low to moderate in Pedon 2 but moderate to high in Pedon 3 indicating a gradual improvement in soil fertility from the summit to the toeslope of the hillslope . Kaolinite, mica, quartz, microcline, plagioclase, goethite and gibbsite were detected in the silt fraction of all the soils while kaolinite and poorly ordered illite as well as Fe-rich chlorite dominated the clay mineralogy. According to the criteria of the USDA Soil Taxonomy, the upland soils are Typic Udorthents while the valley bottom soils are Mollic Fluvaquents. In the FAO-WRB system, they qualify as Hper-Dystric Regosols and Mollic Gleysols respectively. Recommendations regarding soil management options have been included.Key words: acid soils, characterization, classification, Entisols, hillslope

Dissipation and Leaching of Acephate, Chlorpyrifos, and Their Main Metabolites in Field Soils of Malaysia

Preventive treatment with insecticides at high dosing rates before planting of a new crop- soil drenching- is a common practice in some tropical intensive cropping systems, which may increase the risk of leaching, soil functioning, and pesticide uptake in the next crop. The degradation rates and migration of acephate and chlorpyrifos and their primary metabolites, methamidophos and 3,5,6-trichloropyridinol (TCP), have been studied in clayey red yellow podzolic (Typic Paleudults), alluvial (Typic Udorthents), and red yellow podzolic soils (Typic Kandiudults) of Malaysia under field conditions. The initial concentrations of acephate and chlorpyrifos in topsoils were found to strongly depend on solar radiation. Both pesticides and their metabolites were detected in subsoils at the deepest sampling depth monitored (50 cm) and with maximum concentrations up to 2.3 mg kg(-1) at soil depths of 10 to 20 cm. Extraordinary high dissipation rates for weakly sorbed acephate was in part attributed to preferential flow which was activated due to the high moisture content of the soils, high precipitation and the presence of conducting macropores running from below the A horizons to at least 1 m, as seen from a dye tracer experiment. Transport of chlorpyrifos and TCP which both sorb strongly to soil organic matter was attributed to macropore transport with soil particles. The half-lives for acephate in topsoils were 0.4 to 2.6 d while substantially longer half-lives of between 12.6 and 19.8 d were observed for chlorpyrifos. The transport through preferential flow of strongly sorbed pesticides is of concern in the tropics.

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Significant deposits of heavy mineral sands (primarily ilmenite and zircon) are located in Virginia in Dinwiddie, Sussex and Greensville counties. Most deposits are located under prime farmland, and thus require intensive reclamation when mined. The objective of this study was to determine the effect of four different mine soil reconstruction methods on soil properties and associated rowcrop productivity. Treatments compared were 1) Biosolids-No Tillage, 2) Biosolids-Conventional Tillage, 3) Lime+NPK fertilized tailings (Control), and 4) 15-cm Topsoil+lime+NPK over lime+P treated tailings. Treated plots were cropped to corn (Zea mays L.) in 2005 and wheat (Triticum aestivum L.) in 2006. Yields were compared to nearby unmined prime farmland yields. Over both growing seasons, the two biosolids treatments produced the highest overall crop yields. The Topsoil treatment produced the lowest corn yields due to relatively poor physical and chemical conditions, but the effect was less obvious for the following wheat crop. Reclaimed land corn and wheat yields were higher than long-term county averages, but they were consistently lower than unmined plots under identical management. Detailed morphological study of 20 mine soil pedons revealed significant root-limiting subsoil compaction and textural stratification. The mine soils classified as Typic Udorthents (11), Typic Udifluvents (4) and Typic Dystrudepts (5). Overall, these mined lands can be successfully returned to intensive agricultural production with comparable yields to long-term county averages provided extensive soil amendment and remedial tillage protocols are implemented. However, a significant decrease (~25 to 35%) in initial productivity should be expected relative to unmined prime farmland.

Modelo digital de elevação na caracterização de solos desenvolvidos de basalto e material arenítico

Os levantamentos de solos são na maioria antigos e pouco detalhados, geralmente nos níveis exploratório e de reconhecimento. Isso pode ser explicado pelo fato de que o método tradicional de levantamento de solos é lento e caro, requerendo grande número de observações de campo. Assim, o presente trabalho teve como objetivo caracterizar unidades de mapeamento de solos das regiões de Ibaté e São Carlos, SP, desenvolvidos de materiais basálticos e areníticos em função da declividade e altitudes correspondentes, com base em modelo digital de elevação (MDE). Primeiramente, foi feito um mapa de solos semidetalhado pelo método tradicional. Posteriormente, utilizando-se curvas de nível da região, foi elaborado o MDE, do qual foram extraídos mapas com diferentes classes de declividade e elevação. Por meio da tabulação cruzada, foi determinada a incidência de cada solo nas respectivas classes de declives e altitudes. Cada solo apresentou comportamento diferenciado em relação às classes de declive. Contudo, nas faixas limítrofes de declividade pode ocorrer sobreposição de dois ou mais solos. Na referida região, o Latossolo Amarelo encontra-se predominantemente nas regiões mais altas e de relevo plano; entretanto, solos pouco intemperizados, como os Neossolos Litólicos, aparecem em diferentes faixas de declividade. Conclui-se que o conhecimento da distribuição dos solos no relevo é de grande importância, pois facilita a execução do levantamento de solos. O modelo de elevação apresenta semelhanças com o mapa de solos, podendo auxiliar na sua determinação. As variações de solo, no entanto, são mais complexas, não dispensando as observações de campo.

Soil organic carbon stock for reclaimed minesoils in northeastern Ohio

AbstractReclamation of disturbed soils is done with the primary objective of restoring the land for agronomic or forestry land use. Reclamation followed by sustainable management can restore the depleted soil organic carbon (SOC) stock over time. This study was designed to assess SOC stocks of reclaimed and undisturbed minesoils under different cropping systems in Dover Township, Tuscarawas County, Ohio (40°32·33′ N and 81°33·86′ W). Prior to reclamation, the soil was classified as Bethesda Soil Series (loamy‐skeletal, mixed, acid, mesic Typic Udorthent). The reclaimed and unmined sites were located side by side and were under forage (fescue—Festuca arundinacea Schreb. and alfa grass—Stipa tenacissima L.), and corn (Zea mays L.)—soybean (Glycine max (L.) Merr.) rotation. All fields were chisel plowed annually except unmined forage, and fertilized only when planted to corn. The manure was mostly applied on unmined fields planted to corn, and reclaimed fields planted to forage and corn. The variability in soil properties (i.e., soil bulk density, pH and soil organic carbon stock) ranged from moderate to low across all land uses in both reclaimed and unmined fields for 0–10 and 10–20 cm depths. The soil nitrogen stock ranged from low to moderate for unmined fields and moderate to high in some reclaimed fields. Soil pH was always less than 6·7 in both reclaimed and unmined fields. The mean soil bulk density was consistently lower in unmined (1·27 mg m−3 and 1·22 mg m−3) than reclaimed fields (1·39 mg m−3 and 1·34 mg m−3) planted to forage and corn, respectively. The SOC and total nitrogen (TN) concentrations were higher for reclaimed forage (33·30 g kg−1; 3·23 g kg−1) and cornfields (21·22 g kg−1; 3·66 g kg−1) than unmined forage (17·47 g kg−1; 1·98 g kg−1) and cornfield (17·70 g kg−1; 2·76 g kg−1). The SOC stocks in unmined soils did not differ among forage, corn or soybean fields but did so in reclaimed soils for 0–10 cm depth. The SOC stock for reclaimed forage (39·6 mg ha−1 for 0–10 cm and 28·6 mg ha−1 for 10–20 cm depths) and cornfields (28·3 mg ha−1; 32·2 mg ha−1) were higher than that for the unmined forage (22·7 mg ha−1; 17·6 mg ha−1) and corn (21·5 mg ha−1; 26·8 mg ha−1) fields for both depths. These results showed that the manure application increased SOC stocks in soil. Overall this study showed that if the reclamation is done properly, there is a large potential for SOC sequestration in reclaimed soils. Copyright © 2005 John Wiley & Sons, Ltd.

English

Significant areas of prime farmland in the upper Coastal Plain of Virginia have been disturbed by heavy mineral sands (Ti/Zr-bearing ilmenite, rutile, zircon) mining over the past 7 years. Previous work has shown that separation of sandy particles (tailings) from finer particles (slimes) in dewatering pits leads to significant lateral variability in the soils. The objectives of this study were 1) to characterize the chemical, morphological and physical properties of these mine soils and 2) to classify these soils. Thirteen soil profiles, ranging in age from 2 to 6 years, were described and sampled to 2 m. Samples were analyzed for particle size distribution, pH, exchangeable bases, exchangeable acidity, extractable Al, and organic matter (OM). The plow layers, which in most cases included topsoil, fertilizer, lime, and biosolids additions during reclamation, ranged from 10 to 24 cm in depth. These horizons were typically loamy sands and sandy loams with OM ranging from 0.2 to 1.5% and pH ranging from 5.6 to 8.0. Subsurface horizons were typically sands, loamy sands, sandy loams, sandy clay loams, and clays with lower pH, (< 5.5) low OM (< 0.5%), and low plant- available nutrients. Some profiles were relatively consistent in the subsurface, or changed only gradually with depth. Others contained adjacent dissimilar layers with abrupt horizons in between, such as alternating sands and clays. Several profiles contained dissimilar materials within a horizon, expressed as banded materials or as clayey fragments within a sandy matrix. Many profiles exhibited overturned stratification that we refer to as convoluted banding and may prove to be a diagnostic feature of some mineral sand mine soils. Heavy compaction was indicated in most profiles by the presence of densic layers in both loamy and clayey materials. The thirteen profiles were classified according to Soil Taxonomy into 4 subgroups, including one Fluventic Dystrudept, two Typic Udifluvents, three Typic Quartzipsamments, and seven Typic Udorthents.

Mapping and Classification of Southwest Virginia Mine Soils

Mine soils on central Appalachian coal‐mined lands are currently classified by the Soil Taxonomy as Typic Udorthents, which does not distinguish these unique anthropogenic soils from other weakly developed natural soils. Our overall objectives were (i) to critically evaluate currently available USDA‐NRCS mine soil series for classifying a range of mine soil pedons in southwest Virginia, and (ii) to compare two different approaches for detailed Order 1 soil mapping of these highly altered landscapes. Using established series concepts, we mapped and classified 450 ha of mine soils in an area that had been recently reclaimed, and we used these same series concepts to reclassify mine soils in an older adjacent and overlapping 250‐ha mine area that had been mapped using nontaxonomic mine soil classification criteria in 1980. Established mine soil series provided adequate information on particle‐size and reaction class, but did not adequately describe drainage class, rock type, or parent materials. Classification differences occurred on well‐drained soils primarily at the family level and below. There are no established series that describe mine soils with impeded drainage, densic layers, and shallow or moderately deep depth classes, all of which commonly occurred in this study area, and are important criteria for separating soil series. Cambic horizons were also described, and generate classification issues at the order level. Because reaction class, drainage class, densic contacts, and soil depth directly affect soil management, we feel that it is important to recognize these features by establishing new mine soil series or phases of established series. Detailed Order 1 map scales (≤1:12000) are required to adequately resolve and delineate strongly contrasting mine soil landscapes, particularly on older (pre‐1977) mined lands.

English

Soils formed on lands mined for coal in the Central Appalachians are currently classified by Soil Taxonomy primarily as Typic Udorthents, which does not distinguish these unique anthropogenic soils from other weakly developed natural soils. In this study, we evaluated the effectiveness of currently utilized mine soil series for describing and classifying a range of mine soil pedons in southwest Virginia. Using established series concepts, we mapped and classified approximately 450 ha of mine soils in an area that had been reclaimed in accordance with the U.S. Surface Mining, Control, and Reclamation Act (SMCRA) of 1977. We also used current series concepts to reclassify mine soils in an adjacent and overlapping 250 ha that had been mined prior to SMCRA, and had been mapped using older (non Soil Taxonomy) mine soil classification criteria in 1980. Established mine soil series concepts provided adequate information on particle-size and reaction class, but did not adequately describe drainage class, rock type or parent materials. Classification differences occurred on well-drained soils primarily at the family level and below. There were no established series to describe mine soils with impeded drainage, densic layers, and shallow or moderately deep depth classes, all of which commonly occurred in this study area, and are important criteria for separating soil series. Cambic horizons were also described, and generate classification issues at the order level. Using current taxonomic/mapping procedures, none of these dissimilar soils would be considered limiting inclusions to the dominant soil in the map unit. Since reaction class, drainage class, densic contacts, and soil depth directly affect soil management, we feel that it is important to recognize these features by establishing new mine soil series or phases of established series. Older, pre-SMCRA mined lands are much more complex in short-range landform variability than more modern reclaimed landscapes. This pattern of soil landscape variability and associated differences in land use capability is effectively captured by large scale mapping such as that employed by this study.