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Diesel oil infiltration in soils with selected antecedent water content and bulk density

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Journal of Central South University 2016年第8期23卷 1924-1930页

作者：马艳飞李永霞 S.H.Anderson 郑西来冯雪冬高佩玲 Department of Resource and Environmental Engineering Shandong University of Technology Department of Soil Environmental and Atmospheric Sciences University of Missouri Shandong Academy of Environmental Science Key Laboratory of Ocean Environment and Ecology Ministry of Education Ocean University of China

The effects of soil texture, initial water content and bulk density on diesel oil infiltration in fine sand and silty clay loam materials were evaluated. Three physical and two empirical equations express diesel oil infiltration through soils with time, with coefficients of determination greater than 0.99. Diesel oil infiltrates more quickly in the fine sand than in the silty clay loam material. Diesel oil infiltration rates are found to decrease with increasing initial water content and bulk density for the silty clay loam material. The infiltration rate of diesel oil in the fine sand material increases slightly with increasing initial water content. The diesel oil saturated conductivity(Kdiesel) decreases with increasing bulk density for the silty clay loam column. Diesel oil sorptivity(S) decreases linearly with increased initial water content and bulk density of the silty clay loam material. Changes in empirical parameters relative to initial water content and bulk density are similar to the parameter S.

关键词： infiltration diesel oil soil physical and empirical models initial water content bulk density

Variation of soil organic carbon and bulk density during afforestation regulates soil hydraulic properties

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Journal of Mountain Science 2022年第8期19卷 2322-2332页

作者： GU Feng CHEN Xue-jiao SU Zheng-an ZHANG Xin-bao ZHOU Ming-hua Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Sichuan Academy of Environmental Policy and Planning Chengdu 610093China School of Food and Bioengineering Xihua UniversityChengdu 610039China

Grain to Green program on arable land has been conducted for decades in semi-arid regions of North ***,it remains uncertain how afforestation practices affect soil hydraulic properties(SHP).Two afforestation types,***(SL)and woodland(WL),and the adjacent cropland(CL)were investigated to determine afforestation effects on SHP in this *** and undisturbed soil cores were collected in three experimental *** field capacity(FC),wilting point(WP),and available water capacity(AWC)increased in SL compared to the *** saturated water content,however,decreased significantly in both SL and *** and redundancy analysis identified that bulk density(BD)and soil organic carbon(SOC)were the main factors regulating SHP across different land *** saturated water contents in afforestation sites were likely driven by the higher BD,compared to the adjacent ***,WP,and AWC were positively correlated to SOC *** afforestation may not increase the saturated water content of a landscape,our results indicate that it can improve soil water retention and could be an effective practice for soil and water conservation.

关键词： Afforestation bulk density Field capacity Soil hydraulic properties Soil organic carbon Soil water retention curve

Computer programming for prediction of soil bulk density effect on trencher design parameters

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International Journal of Agricultural and Biological Engineering 2011年第4期4卷 42-49页

作者： Mohamed Hassan Dahab Moayed Mohamed balal Department of Agricultural Engineering Faculty of AgricultureShambatUniversity of KhartoumSudan Department of Agricultural Engineering Faculty of Natural Resources and Environmental StudiesElobiedUniversity of North KordofanSudan

A computer program was developed in C++language to predict the effect of soil bulk density on draft force on bottoms,share thickness,stresses distribution and maximum deflection on standards,bending stresses distribution on side plates,diameter of shear pins,and tensile stress on hitch *** was found that,as soil bulk density increased,stresses distribution and maximum deflection on standards,bending stresses distribution on side plates,diameter of shear pins,and tensile stress on hitch bar *** diameter of shear pin should be larger to meet wide range of soil density.

关键词： trencher computer program soil draft force bulk density prediction

bulk density in Jack Bean’s Development Grown in Cerrado Oxisol

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American Journal of Plant Sciences 2015年第9期6卷 1349-1360页

作者： Edna Maria Bonfim-Silva Juliana Terezinha Sasso Paludo Tonny José Araújo da Silva Salomao Lima Guimaraes Department of Agricultural and Environmental Engineering Institute of Agricultural Sciences and TechnologyFederal University of Mato GrossoRondonópolisBrazil

The use of cover plants promotes the recycling of nutrients and the increase in organic mass, and minimizes the effects of erosion. The objective was to evaluate the effect of bulk density in the development of jack bean (Canavalia ensiformis) in Cerrado Oxisol. The experiment was conducted in a greenhouse at the Federal University of Mato Grosso, Rondonópolis-MT, in the period from June to September 2013. Oxisol was used from a Cerrado reserve area, collected at 0 - 0.20 m depth. The experimental design was completely randomized, corresponding to bulk density levels (1.0, 1.2, 1.4, 1.6 and 1.8 Mg·m-3), and five replications. The experimental plot consisted of three PVC rings (polyvinyl chloride) with 150 mm internal diameter, 300 mm total height, where the upper and lower rings of pots were filled with 1.0 Mg·m-3 density soil and intermediaries according to bulk density treatments. The results were submitted to variance analysis and, when significant, to regression analysis, both with a 5% probability, using SISVAR software. At 60 days after germination, number of leaves, stem diameter, plant height, dry mass of leaves, stem dry mass, dry mass of roots, dry mass of nodules, number of nodules and chlorophyll index (SPAD index) were evaluated. The increase in bulk density negatively influences the development of jack bean, showing little efficiency as a decompacting plant in Cerrado Oxisol.

关键词： Canavalia ensiformis bulk density Cover Crops

Comparing Two Methods for Measuring Soil bulk density and Moisture Content

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Open Journal of Soil Science 2020年第6期10卷 233-243页

作者： Jalal D. Jabro William B. Stevens William M. Iversen USDA Agricultural Research Service Northern Plains Agricultural Research Laboratory Sidney Montana USA

Soil bulk density and moisture content are dynamic properties that vary with changes in soil and field conditions and have many agricultural, hydrological and environmental implications. The main objective of this study was to compare between a soil core sampling method (core) and the CPN MC-3 EliteTM nuclear gauge method (radiation) for measuring bulk density (ρB) and volumetric moisture content (θv) in a clay loam soil. Soil ρB and θv measurements were determined using the core and radiation methods at 0 - 10 and 10 - 20 cm soil depths. The mean values of soil ρB obtained using the core method (1.454, 1.492 g·cm−3) were greater than those obtained using the radiation method (1.343, 1.476 g

A New Pulsed Neutron Sonde for Derivation of Formation bulk density Measurement

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A New Pulsed Neutron Sonde for Derivation of Formation Bulk ...

Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray,Ethiopia

2020年中国地球科学联合学术年会

作者： Hu Wang Aizhong Yue HongWei Fan Pingxiu Li Xiaolei Zhang Shusheng Wang Yunfeng Fan The Technical Center of China Petroleum Logging CO.LTD. Daqing Branch China Petroleum Logging CO.LTD.

bulk density is one of the most important formation parameters for formation evaluation. The radioisotope chemical sources are widely used in conventional nuclear logging tools. Considering security and environmental risks, the pulsed neutron generators have successfully replaced the Am-Be source in neutron porosity logging tools. The neutron-induced secondary gamma-ray source cannot be considered as a point source. The distribution of the inelastic gamma source is a function of the neutron transport. Due to the high gamma energy values, the attenuation of inelastic gamma-ray is affected by Compton scattering and pair production. Therefore, the bulk density can be measured when the effects of neutron transport and pair production are considered. A new open hole wireline logging tool has been developed to provide measurement of formation bulk density. The paper reviews the NGD measurement physics and discusses the various facets of bulk density algorithm. Data from laboratory testing examples are presented to demonstrate tool performance.

关键词： neutron-gamma density bulk density neutron transport pair production

来源： cnki会议评论

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Journal of Arid Land 2024年第1期16卷 1-13页

作者： Selam LJALEM Emiru BIRHANE Kassa TEKA Daniel H BERHE Department of Land Resources Management and Environmental Protection College of Dryland Agriculture and Natural ResourcesMekelle UniversityMekelle 231Ethiopia Institute of Climate and Society Mekelle UniversityMekelle 231Ethiopia Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences(NMBU)Ås 1432Norway Department of Natural Resources Management Adigrat UniversityAdigrat 50Ethiopia

Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic *** African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,*** farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,*** trees also could improve soil ***,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological ***,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental *** divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different *** collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil *** density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p H,electrical conductivity(EC),and cation exchange capacity(CEC)were *** revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under ***,and soil p H under ***,all the studied soils were improved under both species canopy as compared with canopy ***,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under *** two parkland agroforestry species significantly enhanced soil fertility near the canopy of top

关键词： agroforestry bulk density carbon stock dispersed tree soil texture tree canopy

Effects of Biochar and Soil Organic Matter Levels on Physicochemical Properties of Mollisol and Soybean's Biomass

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Journal of Northeast Agricultural University(English Edition) 2024年第3期31卷 33-41页

作者： Zhang Shuaikun Xu Zhiyuan Shi Fangfang Yang Jing Luo Xu Jiang Zhenfeng Liu Zhihua College of Resources and Environment Northeast Agricultural UniversityHarbin 150030China College of Agriculture Northeast Agricultural UniversityHarbin 150030China

Long term tillage in mollisol of Northeast China has led to an inhomogeneous distribution of soil organic matter ***,a carbon material,changes the soil carbon pool and physical-chemical characteristics after adding to the ***,the mechanism remains unclear for the relation between the soil organic matter level and biochar ***,the soil physical and chemical properties and soybean growth in a two-year pot experiment were detected at three levels of soil organic matter and three biochar additions(0,1%and 10%).The difference was found in two biochar application *** 1%biochar addition had no positive effect on the soil chemical properties based the two-year ***,10%biochar application significantly increased the soil water content(8.0%-39.7%),the total porosity(9.7%-21.3%),pH(0.26-0.84 unit),organic matter content(89.0%-261.2%),and the available potassium content(29.0%-109.1%).The biomass of soybean increased by 19.4%-78.1%after biochar addition,yet,the soil bulk density reduced at the range of 12.6%-26.0%by 10%biochar *** the 100-grain weight was correlated to the interaction of biochar and the native soil organic *** the indicators showed that the interaction between biochar and soil organic matter level was weak in *** effects of biochar on the physical-chemical properties relied on its *** biochar is applied to the soil,the amount of biochar should be considered rather than the native soil organic matter level.

关键词： biochar soil organic matter bulk density available nutrient

STUDY ON THE EROSION RATE OF POWDERED ACTIVATED CARBON IN RAW WATER AQUEDUCT

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Journal of Hydrodynamics 2012年第3期24卷 442-449页

作者： YIN Hai-long YANG Yang XU Zu-xin ' State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Key Laboratory of Yangtze River Water Environment Ministry of Education Shanghai 200092 China

Growing interest in using Powdered Activated Carbon （PAC） in raw water aqueduct, as a method of polluted surface water treatment, raises the question of transport of PAC in the aqueduct, which is related to the potential PAC erosion along the aqueduct. By means of a recently developed re-circulating flume, erosion rates of PAC with the grain size of 230 meshes （less than 62μm） depending on shear stress and bulk density were the discussed with real-time measurement of suspended PAC concentration. Lateral cross sectional averaging shear stress was decided by the actual value in the raw water conveying aqueduct of upstream Huangpu River, Shanghai, China, smaller than 1.8 N＇m 2. As for the bulk density, it was measured with compacting times varying from 1 d to 15 d, equivalent to 1 550 kg/m3-1 800 kg/m3. Experiments were conducted for the shear stress and bulk density separately, so as to isolate and quantify the effects of one of the parameters. The results demonstrate that, for a particular PAC particle, the erosion rate increases with shear stress and decreases with bulk density as a function of power form. A product of powers of the lateral cross sectional averaging shear stress and bulk density to estimate PAC erosion rate is presented by approximating experimental data sets.

关键词： Powdered Activated Carbon (PAC) raw water aqueduct erosion rate shear stress bulk density