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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

Coupling the 4M crop model with national geo-databases for assessing the effects of climate change on agro-ecological characteristics of Hungary

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International Journal of Digital Earth 2014年第5期7卷 391-410页

作者： Nandor Fodor Laszlo Pasztor Tamas Nemeth Institute for soil science and agricultural chemistry Centre for Agricultural ResearchHungarian Academy of SciencesBudapestHungary Hungarian Academy of sciences BudapestHungary

The 4M crop model was used to investigate the prospective effects of climate change on the agro-ecological characteristics of *** model was coupled with a detailed meteorological database and spatial soil information systems covering the whole territory of ***-specific model parameters were determined by inverse *** meteorological data were produced from the present meteorological data by combining a climate change scenario and a stochastic weather *** the available and the generated data,the present and the prospective agro-ecological characteristics of Hungary were *** to the simulation results,average yields will decrease considerably(-30%)due to climate *** rate of nitrate leaching will prospectively decrease as *** fluctuations of both the yields and the annual nitrate leaching rates will most likely increase approaching the end of the twenty-first *** the basis of the simulation results,the role of autumn crops is likely to become more significant in *** achieved results can be generalized for more extended regions based on the concept of spatial(geographical)analogy.

关键词： agro-ecological features crop modeling climate change effects spatial soil information systems

ACCUMULATION OF TRANSITION METALS IN Fe-Mn CONCRETIONS FROM SELECTED soilS IN NORTH HUAI REGION,JIANGSU AND ITS ENVIRONMENTAL-GEO-CHEMICAL SIGNIFICANCE

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Chinese science Bulletin 1990年第4期35卷 329-333页

作者：潘根兴 Department of soil science and agricultural chemistry Nanjing Agricultural University Nanjing 210014 PRC

In an attempt to provide more data about the mechanics of transition metal occurrence and translocation in soil environments, Fe-Mn concretions are separated from bulk samples of representative soil types and the element contents are determined. The results are reported and discussed in the sense of environmental geochemistry in this article.

关键词： pedogenic Fe-Mn concretion transition metals environmental geochemistry

Resistance and resilience of soil biological indicators:A case study with multi-walled carbon nanotube

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Pedosphere 2024年第3期34卷 664-675页

作者： Shagufta YASMEEN Nintu MANDAL Anupam DAS Pritam GANGULY Sanjay KUMAR Rajiv RAKSHIT Department of soil science and agricultural chemistry Bihar Agricultural UniversitySabourBhagalpur 813210(India) Department of Agronomy Bihar Agricultural UniversitySabourBhagalpur 813210(India)

soil ecosystem is experiencing stresses due to climate change,and soil inhabitants try to demonstrate their inherent resistance and resilience against those *** of nanomaterials as agricultural inputs could bring shifts in resistance and resilience patterns of soil microbes and associated enzymes,especially under short-term heat *** this background,the impacts of multi-walled carbon nanotube(MWCNT)on the resistance and resilience of soil biological indicators were *** incubation experiment was conducted with varied MWCNT concentrations(0,50,100,250,and 500 mg kg-1soil)for 90 d after 24-h heat stress at 48±2?C to assess the impacts of MWCNT on soil enzyme activities and microbial populations vis-à-vis their resistance and resilience indices under short-term exposure to heat *** activities were reduced after exposure to heat *** indices of enzyme activities were enhanced by MWCNT application on day 1 after heat stress,whereas there was no recovery of enzyme activities after 90-d *** soil enzyme activities,resistance index values of soil microbial populations followed the similar trend and were improved by MWCNT ***-walled carbon nanotube has the potential to improve resistance indices of soil enzyme activities and microbial populations under heat stress,although they could not recover to their original state during periodical incubation after heat *** study helps to understand the relative changes of biological indicators under MWCNT and their ability to withstand heat stress.

关键词： enzyme activity heat stress microbial population nanomaterial recovery