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Free Oxide Distribution in Poorly and Well Drained soils Developed on Calcareous Alluvial Deposits

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Pedosphere 2003年第4期13卷 345-351页

作者： N. K. MOUSTAKAS P. E. BAROUCHAS agricultural University of Athens Laboratory of Soil Science and Agricultural Chemistry 75 /era Odos Botanikos 11855Agricultural University of Athens Laboratory of Soil Science and Agricultural Chemistry 75 /era Odos Botanikos 11855

A study on the distribution of free iron and manganese oxides was conducted in soils developed on calcareous alluvial deposits under subhumid climatic conditions, in Western Greece. soil samples from two well drained soils and from two poorly drained soils, classified as Alfisols, were collected and used in this study. After certification of soil homogeneity the acid ammonium oxalate and dithionite-citrate-bicarbonate methods were used to extract free iron and manganese oxides from the samples. Iron oxides extracted by the dithionite-citrate-bicarbonate method (Fed) were significantly higher than the iron oxides extracted by the ammonium oxalate method (Feo), indicating that a considerable fraction is present in crystalline forms,independent of drainage status. A confirmation of free iron oxides and fine clay was detected. The ratios Feo/Fed and (Fed-Feo)/total Fe (Fet) could not be used to distinguish the well drained soils from the poorly drained soils. Manganese movement in a soluble form is independent of the fine clay.

关键词： argillic horizon calcareous alluvial deposits iron oxides manganeseoxides soil homogeneity

Effects of Organic Amendments on soil Physical Attributes and Aggregate-Associated Phosphorus Under Long-Term Rice-Wheat Cropping

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Pedosphere 2018年第5期28卷 823-832页

作者： Tarik MITRAN Pabitra Kumar MANI Prasanta Kumar BANDYOPADHYAY Nirmalendu BASAK Department of agricultural chemistry and soil science Bidhan Chandra Krishi Viswavidyalaya

The quantification of phosphorus(P) in bulk soil and P distribution in different size fractions of water-stable aggregates(WSAs)are important for assessing potential P loss through runoff. We evaluated available and total P distribution within WSAs of a sitty clay to clay soil in a long-term fertility experiment of a rice-wheat cropping system in India. Surface soil samples were collected from seven plots amended with NPK fertilizers in combination with or without organic amendments, farmyard manure(FYM), green manure(GM), and paddy straw(PS). The plot with no NPK fertilizers or organic amendments was set as a control. The soil samples were separated by wet sieving into four soil aggregate size fractions: large macroaggregates(> 2.0 mm), small macroaggregates(0.25–2.0 mm), fine microaggregates(0.05–0.25 mm), and a silt + clay-sized fraction(soil receiving organic amendments than in the soil receiving inorganic fertilizer alone. Organically amended soil had a higher proportion of stable macroaggregates than the control and the soil receiving inorganic fertilizer alone, which were rich in microaggregates. Total and available P contents within WSAs were inversely related to the aggregate size, irrespective of treatment. The distribution of available and total P in the soil aggregate size fraction was as follows: silt + clay-size fraction > small macroaggregates > fine microaggregates> large macroaggregates. Within a size class, aggregate-associated available and total P contents in the organically amended soil were in the following order: FYM > PS ≥ GM. The available P content of the microaggregates( 0.25 mm), and the total P content of the microaggregates was 4-to 5-times higher than that of the macroaggregates. Cultivation without organic amendments resulted in more microaggregates that could be checked by the application of organic amendments such

关键词： aggregate size fractions clay content crop rotation organic inputs soil aggregates soil particles soil physical properties

Nature of soil Acidity in Relation to Properties and Lime Requirement of Some Inceptisols

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Pedosphere 2003年第2期13卷 181-188页

作者： A.K.DOLUI S.BHATTACHARJEE division of agricultural chemistry and soil science University College of Agriculture Calcutta UniversityDivision of Agricultural Chemistry and Soil Science University College of Agriculture Calcutta University 35 Ballygunge Circular Road Kolkata 700 019 (India) 35 Ballygunge Circular Road Kolkata 700 019 (India)

Some Inceptisols representing the Singla catchment area in Karimgaungedistrict of Assam, India, were studied for lime requirement as influenced by the nature of soilacidity. The electrostatically bonded (EB)-H^+ and EB-Al^(3+) acidities constituted 33 and 67percent of exchangeable acidity while EB-H^+, EB-Al^(3+), exchangeable and pH-dependent aciditiescomprised 6, 14, 20 and 80 percent of total potential acidity. The pH-dependent acidity made a majorcontribution towards the total potential acidity (67%～84%). Grand mean of lime requirementdetermined by the laboratory incubation method and estimated by the methods of New Woodruff,Woodruff and Peech as expressed in MgCaCO_3 ha^(-1) was in the order: Woodruff (15.6) > New Woodruff(14.9) > Peech (5.1) > incubation (5.0). Correlations analysis among different forms of acidity andlime requirement methods with selected soil properties showed that pH in three media, namely water,1 mol L^(-1) KC1 and 0.01 mol L^(-1) CaCl_2, had a significant negative correlation with differentforms of acidity and lime requirement methods. Exchangeable Fe and Al showed significant positivecorrelations with EB-Al^(3+) acidity, exchangeable acidity, pH-dependent acidity and total potentialacidity, and also lime requirement methods. Extractable Al showed positive correlations withdifferent forms of acidity except EB-H^+ and EB-Al^(3+) acidities. The lime requirement by differentmethods depended upon the extractable aluminium. Significant positive correlations existed betweenlime requirements and different forms of acidity of the soils except EB-H^+ acidity and incubationmethod. The nature of soil acidity was mostly pH-dependent. Statistically, the Woodruff method didslightly better than the New Woodruff, incubation and Peech methods at estimating lime requirementand hence the Woodruff procedure may be recommended for routine soil testing because of its speedand simplicity.

关键词： inceptisols lime requirement nature of acidity soil properties

Phosphate Sorption-Desorption Characteristics in Two Inceptisols and an Alfisol of Chattisgarh, India

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Pedosphere 2005年第5期15卷 611-619页

作者： A. K. DOLUI S. S. ROY Department of agricultural chemistry and soil science Institute of Agricultural Science Calcutta University 35 Bally-gunge Circular Road Kolkata 700 019 (India).Department of Agricultural Chemistry and Soil Science Institute of Agricultural Science Calcutta University 35 Bally-gunge Circular Road Kolkata 700 019 (India).

Two Inceptisols and an Alfisol of the Indravati Catchment area in Chattisgarh, India, comprising several gradientsin physical and chemical properties were studied to relate phosphate sorption and desorption to soil properties. Fromthe P isotherm curve, the standard P requirement (SPR) of the soils was determined. Phosphate sorption data were alsofitted both to the Langmuir and Freundlich Equations. The mean sorption maximum values for three different soil serieswere: Bastar > Geedam > Mosodi. The fraction of added phosphate sorbed for the 3 series followed this same trend asdid SPR; the phosphate sorption maximum and the maximum phosphate buffering capacity, which were estimated by theLangmuir isotherm; and the Freundlich constant 1/n. However, phosphate desorption, as well as the maximum recoverypercent did not follow this order. The phosphate affinity constant (K) was also different following the same progressionfor the 3 soil series as the Freundlich constant K’, which measured sorption strength. Meanwhile, an inverse order existedfor K and K’ versus the percent desorbed relative to the sorbed as well as the maximum recovery percent. In addition,significant correlation coefficients among sorption parameters of P and soil factors were found.

关键词： Alfisols Inceptisols phosphate sorption-desorption

Evaluating Fertilization Effects on soil Physical Properties Using a soil Quality Index in an Intensive Rice-Wheat Cropping System

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Pedosphere 2016年第6期26卷 887-894页

作者： Bappa DAS Debashis CHAKRABORTY Vinod Kumar SINGH Mukhtar AHMED Amit Kumar SINGH Arijit BARMAN division of agricultural Physics Indian Agricultural Research InstituteNew Delhi 110012(India) Project Directorate for Farming Systems Research ModipuramMeerut 250110(India) division of soil science and agricultural chemistry Indian Agricultural Research InstituteNew Delhi 110012(India)

soil quality assessment has been suggested as an effective tool for evaluating sustainability of soil and crop management *** objective of this study was to develop a sensitive soil quality index(SQI) based on bulk density(BD),water-holding capacity(WHC),water-stable aggregates(WSA),aggregate mean weight diameter(AMWD),total organic C(TOC) and C input to evaluate the important rice-wheat cropping system on an Inceptisol in India.A long-term experiment has been conducted for 18 years at the Indian Council of agricultural Research-Indian Institute of Farming Systems Research,Modipuram,*** treatments selected for this study were comprised of a no-fertilizer control and N,P and K fertilizers(NPK) combined with Zn and S fertilizers(NPK+ Zn+S),farmyard manure(NPK+FYM),green gram residues(NPK+GR) and cereal residues(NPK+CR),laid out in a randomized complete block design with three *** samples were collected and analyzed for BD,WHC,WSA and *** analysis revealed that both rice and wheat yields signi?cantly increased with the increases in AMWD,TOC and C input,but decreased with the increase in *** SQI values were then generated based on regression analysis of BD,WSA,AMWD,TOC and C input with rice and wheat yields for the 0–15 and 15–30 cm soil layers,*** analyses between crop yields and SQI values showed a quadratic type of relation with the coeffcient of determination(R^2) varying from 0.78 to *** regard to soil sustainability,applying crop residues to both rice and wheat could maintain soil quality for a longer period,whereas the highest yields of both the crops were recorded in the NPK+Zn+S *** regression equations developed in this study could be used to monitor soil quality in a subhumid tropical rice-wheat cropping system.

关键词： bulk density C input integrated nutrient management total organic C water-holding capacity water-stable aggregates

Phosphate Adsorption and Surface Charge Characteristics and Their Relations to Mineralogy of Some soils from Southern China

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Pedosphere 1998年第4期8卷 297-304页

作者： ZHANG MINGKUI M. J. WILSON HE ZHENLI L. CLARK and D. M. L. DUTHIE (Department of soil science and agricultural chemistry, Zhejiang agricultural University, Hanyzhou 310029 China) (soils and soil Microbiolopy division, Macaulay Land Use Research Institu Department of soil science and agricultural chemistry Zhejiang Agricultural University Hangzhou 310029 (China) ***

The phosphate adsorption and surface charge characteristics of the tropical and subtropical soils derived from different parent materials in China were determined, and their relations to soil mineralogy were *** results showed that all soil phosphate adsorption curves were well fitted by Freundlich equation and Langmuir equation. The maximum buffering capacity of P ranged from 66 to 9880 mg kg-1, with an increasing order of purple soil, skeletal soil, red soil, lateritic red soil, yellow soil and latosol; and the highest value was 149 times the lowest value, which indicated great differences among these soils in phosphate adsorption and supplying characteristics. The pHo (zero point of charge) values obtained by salt titrationpotential titration varied from 3.03 to 5.49, and the highest value was found in the latosol derived from basalt whereas the lowest value was found in the purple soil. The correlation analysis indicated that the main minerals responsible for phosphate adsorption in the soils were gibbsite, amorphous iron oxide and kaolinite; and the pHo was mainly controlled by kaolinite, gibbsite and oxides.

关键词： mineralogy pH_0 phosphate adsorption tropical and subtropical soils

Assessment of physically-based and data-driven models to predict microbial water quality in open channels

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Journal of Environmental sciences 2010年第6期22卷 851-857页

作者： Minyoung Kim Charles P.Gerba Christopher Y.Choi agricultural Safety Engineering division Department of Agricultural EngineeringNational Academy of Agricultural ScienceRural Development Administration(Korea) Department of soil Waterand Environmental Sciencethe University of Arizona Department of agricultural and Biosystems Engineering the University of Arizona

In the present study, a physically-based hydraulic modeling tool and a data-driven approach using artificial neural networks （ANNs） were evaluated for their ability to simulate the fate and transport of microorganisms in a water system. To produce reliable data, a pipe network was constructed and a series of experiments using a fecal coliform indicator （Escherichia coli 15597） was conducted. For the physically-based model, morphological （pipe size, link length, slope, etc.） and hydraulic （flow rate） conditions were used as input variables, and for ANNs, water quality parameters （conductivity, pH, and turbidity） were used. Both approaches accurately described the fate and transport of microorganisms （physically-based model： correlation coefficient （R） in the range of 0.914 - 0.977 and ANNs： R in the range of 0.949 - 0.980）, with the exception of one case at a low flow rate （q = 31.56 cm^3/sec）. This study also indicated that these approaches could be complementarily utilized to assess the vulnerability of water facilities and to establish emergency plans based on hypothetical scenarios.

关键词： transport open channel artificial neural networks Escherichia coli

Sensitivity of Labile soil Organic Carbon Pools to Long-Term Fertilizer, Straw and Manure Management in Rice-Wheat System

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Pedosphere 2015年第4期25卷 534-545页

作者： Dinesh K.BENBI Kiranvir BRAR Amardeep S.TOOR Shivani SHARMA Department of soil science Punjab Agricultural University

Labile soil organic carbon （SOC） pools, estimated through chemical fractionation techniques, are considered sensitive indicators of management-induced changes in quality and composition of soil organic matter. Although the impacts of organic manure and crop residue applications on C sequestration in rice-wheat system are fairly well documented, their influence on labile SOC pools is relatively less known. Impacts of organic manure, rice straw, and inorganic fertilizer nitrogen （N） applications on soil total organic carbon （TOC） and SOC pools including water-extractable organic C （WEOC）, hot water-soluble organic C （HWOC）, potassium permanganate- oxidizable organic C （KMnO4-C）, microbial biomass C （MBC）, mineralizable organic C （Cmin）, and the oxidizable fractions of decreasing oxidizability （easily-oxidizable, oxidizable, and weakly-oxidizable） were investigated in an ll-year field experiment under rice-wheat system. The field experiment included treatments of different combinations of farmyard manure, rice straw, and fertilizer N application rates, with C inputs estimated to be in the range from 23 to 127 Mg ha-1. After 11 years of experiment, WEOC, HWOC, and KMnO4-C were 0.32%-0.50%, 2.2%-3.3%, and 15.0%-20.6% of TOC, respectively. The easily-oxidizable, oxidizable, and weakly-oxidizable fractions were 43%-57%0, 22%-27%, and 10%-19% of TOC, respectively. The applications of farmyard manure and rice straw improved WEOC, HWOC, KMnO4-C, easily-oxidizable fraction, Cmin, and MBC, though the rates of change varied considerably from -14% to 145% and -1170 to 83% of TOC, respectively. At the C input levels between 29 and 78 Mg C ha-1 during the ll-year period, the greatest increase was observed in WEOC and the minimum in KMnO4-C. Water-extractable organic C exhibited a relatively greater sensitivity to management than TOC, suggesting that it may be used as a sensitive indicator of management-induced changes in soil organic matter under rice-wheat system. All the other la

关键词： metabolic quotient mineralizable C organic amendments oxidizable C soil microbial biomass soil organic matter water-soluble C

Treatment of tunnel wash waters-experiments with organic sorbent materials. PartⅡ: Removal of toxic metals

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Journal of Environmental sciences 2008年第8期20卷 1042-1045页

作者： PARUCH Adam M ROSETH Roger Bioforsk-the Norwegian Institute for agricultural and Environmental Research Soil and Environment Division

In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxicant pollutants defined in surface water quality criteria. Concentrations of these metals in the collected effluent...

关键词： electrostatic filters reduction level sorbents tunnel toxic metals treatment efficiency wash water

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