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Incorporation of Biochar Carbon into Stable Soil Aggregates:The Role of Clay Mineralogy and Other Soil Characteristics

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Pedosphere 2017年第4期27卷 694-704页

作者： Charlene N. KELLY Joseph BENJAMIN Francisco C. CALDERON Maysoon M. mikha David W. RUTHERFORD Colleen E. ROSTAD West Virginia University Division of Forestry and Natural Resources337 Percival HallMorgantownWV 26506USA USDA-ARS Central Great Plains Research Station40335 County RoadGGAkronCO 80720USA U.S.Geological Survey MS 408PO Box 25046Building 95Denver Federal CenterDenverCO 80225USA

Aggregation and structure play key roles in water-holding capacity and stability of *** this study,the incorporation of carbon(C) from switchgrass biochar into stable aggregate size fractions was assessed in an Aridisol(from Colorado,USA) dominated by 2:1 clays and an Alfisol(from Virginia,USA) containing weathered mixed 1:1 and 2:1 mineralogy,to evaluate the effect of biochar addition on soil *** biochar was applied at 4 levels,0,25,50,and 100 g kg^(-1),to the soils grown with wheat in a growth chamber *** changes in soil strength and water-holding capacity using water release curves were *** the Colorado soil,the proportion of soil occurring in large aggregates decreased,with concomitant increases in small size *** changes in aggregate size fractions occurred in the Virginia *** the Colorado soil,C content increased from 3.3 to 16.8 g kg^(-1),whereas in the2 000 μm *** greatest increase(from 6.2 to 22.0 g kg^(-1)) occurred in the 53–250 μm *** results indicated that C was incorporated into larger aggregates in the Virginia soil,but remained largely unassociated to soil particles in the Colorado *** addition had no significant effect on water-holding capacity or strength *** biochar to more weathered soils with high native soil organic content may result in greater stabilization of incorporated C and result in less loss because of erosion and transport,compared with the soils dominated by 2:1 clays and low native soil organic content.

关键词： aggregate size fractions, aggregate stability, mineralogy, soil strength, water-holding capacity, weathered soil

Switchgrass Biochar Effects on Plant Biomass and Microbial Dynamics in Two Soils from Different Regions

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Pedosphere 2015年第3期25卷 329-342页

作者： Charlene N.KELLY Francisco C.CALDERóN Verónica ACOSTA-MARTíNEZ Maysoon M.mikha Joseph BENJAMIN David W.RUTHERFORD Colleen E.ROSTAD Western Carolina University Department of Geosciences and Natural Resources331 Stillwell HallCullowheeNC 28723 (USA) U.S.Geological Survey Denver CO 80225 (USA) USDA-ARS Akron CO 80720 (USA) USDA-ARS Lubbock TX 79403 (USA)

Biochar amendments to soils may alter soil function and fertility in various ways, including through induced changes in the microbial community. We assessed microbial activity and community composition of two distinct clayey soil types, an Aridisol from Colorado （CO） in the U.S. Central Great Plains, and an Alfisol from Virginia （VA） in the southeastern USA following the application of switchgrass （Panicum virgatum） biochar. The switchgrass biochar was applied at four levels, 0%,0, 2.5%, 5%, and 10%, approximately equivalent to biochar additions of 0, 25, 50, and 100 t ha^-1, respectively, to the soils grown with wheat （Triticum aestivum） in an eight-week growth chamber experiment. We measured wheat shoot biomass and nitrogen （N） content and soil nutrient availability and N mineralization rates, and characterized the microbial fatty acid methyl ester （FAME） profiles of the soils. Net N mineralization rates decreased in both soils in proportion to an increase in biochar levels, but the effect was more marked in the VA soil, where net N mineralization decreased from -2.1 to -38.4 mg kg^-1. The 10% biochar addition increased soil pH, electrical conductivity, Mehlich- and bicarbonate-extractable phosphorus （P）, and extractable potassium （K） in both soil types. The wheat shoot biomass decreased from 17.7 to 9.1 g with incremental additions of biochar in the CO soil, but no difference was noted in plants grown in the VA soil. The FAME recovery assay indicated that the switchgrass biochar addition could introduce artifacts in analysis, so the results needed to be interpreted with caution. Non-corrected total FAME concentrations indicated a decline by 457o and 34% with 10% biochar addition in the CO and VA soils, respectively, though these differences became nonsignificant when the extraction efficiency correction factor was applied. A significant decline in the fungi：bacteria ratio was still evident upon correction in the CO soil with biochar. Switchgrass biochar had the p

关键词： correction factor extraction efficiency fatty acid methyl ester profile nitrogen mineralization soil microbial community soil nutrient availability wheat

Pump Intensity Dependence of Two-Beam Coupling in Doped Lithium Niobate Crystals

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Chinese Physics Letters 2000年第6期17卷 431-432页

作者： Nouel Y.Kamber XU Jing-Jun Sonia M.mikha SONG Feng ZHANG Guo-Quan ZHANG Xin-Zheng LIU Si-Min ZHANG Guang-Yin Photonics Research Center College of Physics ScienceNankai UniversityTianjin 300071

We demonstrated experimentally the dependence of two-beam coupling on the incident pump intensity in our samples of doped LiNbO_(3)*** results show that there is an optimum pump intensity for the signal beam amplification,which can be easily controlled by doping the LiNbO_(3)crystal with suitable concentrations of Fe and damage-resistant dopants such as Mg,In,and Zn.

关键词： pump dopant beam

Potato (Solanum tuberosum L.) Flour Enriched with Date Palm Fruit (Phoenix dactylifera L.) Powder and Bean Milk for Cookies Production

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Agricultural Sciences 2022年第9期13卷 973-988页

作者： mikhaïl Akhobakoh Bertrand Zing Zing Alban Ngatchou Josiane Emilie Germaine Mbassi Eileen Bogweh Nchanji Laboratory of Food Science and Technology Institute of Agricultural Research for Development (IRAD) Yaounde Cameroon International Center for Tropical Agriculture Nairobi Kenya

This study emphasizes the formulation of three types of cookies viz potato flour with date powder and bean milk (PDBM), potato flour with sugar and bean milk (PSBM), and potato flour, sugar, and eggs as control. After the substitution, the highest protein content was observed in PDBM (1.78 ± 0.12)% followed by PSBM, (1.35 ± 0.01)% and the lowest was in the control (0.91 ± 0.55)%. Moreover, cookies fortified with date palm powder increased the carbohydrate and fat contents compared to the control and significantly increased the calorific value of PDBM. The formulated cookies were significantly higher (p < 0.05) in iron (39.95 ± 3.00) mg/100 g and zinc (13.65 ± 1.61) mg/100 g in PDBM compared to other cookies. The date palm powder incorporated in cookies significantly increases the darkening of biscuits during cooking. The organoleptic characteristics of PDBM and PSBM were rated overall best when specific parameters were tested. With the shortage of wheat and importation constraints, an alternative provides a great market opportunity for local products like potatoes and beans. In addition, fortifying food products as cookies eaten by all will contribute to a more food and nutrition-secured world.

关键词： Potato Flour Date Palm Cookies Bean Milk Physical Color Sensory Evaluation Food and Nutrition Security

Soil Carbon Changes Influenced by Soil Management and Calculation Method

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Open Journal of Soil Science 2013年第2期3卷 123-131页

作者： Maysoon M. mikha Joseph G. Benjamin Ardell D. Halvorson David C. Nielsen US Department of Agricultural Agricultural Research Service Central Great Research Station Akron USA US Department of Agricultural Agricultural Research Service Northern Plains Soil Plant Nutrient Research Fort Collins USA

Throughout the years, many studies have evaluated changes in soil organic carbon (SOC) mass on a fixed-depth (FD) basis without considering changes in soil mass caused by changing bulk density (ρb). This study evaluates the temporal changes in SOC caused by two factors: 1) changing SOC concentration;and 2) changing equivalent soil mass (ESM) in comparison with FD. In addition, this study evaluates calculating changes in SOC stock over time using a minimum equivalent soil mass (ESMmin) basis from a single sampling event compared with the FD scenario. A tillage [no-tillage (NT) and chisel plow (CP)]-crop rotation (multiple crop and continuous corn), and irrigation (full and delayed)) study was initiated in 2001 on Weld silt loam soil. After seven years, SOC concentration in the 0 - 30 cm depth was 19.7% greater in 2008 compared with 2001. Standardizing the soil mass of 2001 to the ESM of 2008 for each individual treatment showed an average gain in SOC of 5.8 Mg C·ha-1 in 2008 compared with 2001. However, the increase in SOC using ESM was twice the SOC gained with the FD calculation, where some treatments lost SOC after seven years of management. Estimating SOC levels using the ESMmin and, thereby, eliminating the confounding effect of soil ρb indicated that SOC stock was influenced by crop species and their interaction with irrigation, but not by tillage practices. Over all, the ESM calculation appears to be more effective in evaluating SOC stock than the FD calculation.

关键词： Soil Organic Carbon Stock Equivalent Soil Mass Minimum Equivalent Soil Mass Fixed-Depth Management Practices

Surgical Closure of Isolated Patent Ductus Arteriosus in Cenhosoa Antananarivo

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World Journal of Cardiovascular Surgery 2023年第7期13卷 111-119页

作者： Zakarimanana Lucas Randimbinirina Harijaona Fanomezantsoa Randrianandrianina Tsirimalala Rajaobelison Rija mikhaël Miandrisoa Hariniaina Ravaoavy Toky Mamin’ny Aina Rajaonanahary Andriamihaja Jean-Claude Rakotoarisoa Department of Cardiovascular Surgery Faculty of Medicine of Antananarivo University of Antananarivo Antananarivo Madagascar Department of Cardiology Faculty of Medicine of Antananarivo University of Antananarivo Antananarivo Madagascar Cardiovascular Disease Unit Soavinandriana Hospital Center Antananarivo Madagascar Department of Vascular Surgery Faculty of Medicine of Antananarivo University of Antananarivo Antananarivo Madagascar Department of Thoracic Surgery Faculty of Medicine of Antananarivo University of Antananarivo Antananarivo Madagascar

Introduction: Patent ductus arteriosus (PDA) is a congenital heart disease whose seriousness lies in the risk of pulmonary hypertension, congestive heart failure and death. The aim of this study was to describe the surgical closure of an isolated patent ductus arteriosus (PDA) performed in Soavinandriana Teaching Hospital. Methods: This was a retrospective and descriptive study, during thirteen-years-period (January 2004 to December 2016), performed at Cardiac surgery unit of Soavinandriana Teaching Hospital, including all children underwent surgical closures of an isolated PDA. Demographic data, birth weight, clinical signs, diagnostic imaging, time between diagnosis and surgery and hospital left stays were analyzed. Results: A total of eighty-six children were recorded, including 21 males (24.42%) and 65 females (75.58%), giving sex ratio of 30%. The average age was 33.91 months. Children were born with a low birth weight in 12.79% of cases. PDA was symptomatic in 81.39%. The most circumstances of discovery were recurrent lung infections (31.40%), dyspnea (24.41%) and failure to thrive (19.76%). Echocardiography showed left ventricular dilatation (63.95%), pulmonary hypertension (73.25%). The ductus was large in 97.67% and the mean diameter was 5 mm. Chest X-ray showed cardiomegaly (97.67%) and increased pulmonary vascularity (86.04%). Mean delay of surgical procedures after diagnosis was 15.16 months. Surgical procedures consisted left posterolateral thoracotomy with a section and suture after clamping the ductus. Earlier postoperatives courses were simple in all children. The mean duration of hospitalization was 8.93 days. Conclusion: PDA was most common large (97%) and symptomatic (81%) in our study. Surgical closure of an isolated PAD was the only surgical procedure of congenital heart cardiopathy available in Antananarivo.

关键词： Echocardiography Patent Ductus Arteriosus Pediatrics Surgery Thoracotomy

Water Deficit Stress Effects on Corn (<i>Zea mays</i>, L.) Root:Shoot Ratio

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Open Journal of Soil Science 2014年第4期4卷 151-160页

作者： J. G. Benjamin D. C. Nielsen M. F. Vigil M. M. mikha F. Calderon Central Great Plains Research Station USDA-ARS Akron USA

A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation management. Water deficit stress (Dstress) was quantified by the number of days when the water content in the surface 0.3 m deviated from the water content range determined by the Least Limiting Water Range (LLWR). Root and shoot samples were collected at the V6, V12, and R1 growth stages. There was no significant correlation between Dstress and shoot or root biomass at the V6 growth stage. At the V12 and R1 growth stages, there were negative, linear correlations among Dstress and both root biomass and shoot biomass. The proportional decrease of shoot biomass was greater than the proportional decrease in root biomass, leading to an increase in the root:shoot ratio as water deficit stress increased at all growth stages. Determining restrictive soil conditions using the LLWR may be useful for evaluating improvement or degradation of the soil physical environment caused by soil management.

关键词： Shoot Ratio Least Limiting Water Range Water Stress Corn Root Development Soil Environment