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Dynamic monitoring of soil bulk density and infiltration rate during coal mining in sandy land with different vegetation

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International Journal of Coal Science & Technology 2014年第2期1卷 198-206页

作者： Yinli Bi Hui Zou Chenwei Zhu College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China

To investigate the effects of coal mining on soil physical properties,sandy lands with three major vegetation types(Salix psammophila,Populus simonii,and Artemisia ordosica)were investigated by the ring knife method and double-ring ***,variations in soil bulk density and water infiltration rate and the influences of coal mining and vegetation type on the properties during different subsidence stages were studied at the Shendong Bulianta *** results showed that,in the period before mining,soil bulk density occurred in the order ***>***>***,with a negative correlation between the initial infiltration rate and steady infiltration rate being *** the period during mining and 3 months after mining,there were no significant differences in soil bulk density and water infiltration rate among vegetation *** 1 year after mining,the soil bulk density occurred in the order ***>***>***,having a negative correlation with the steady infiltration *** water infiltration depths of the ***,*** and *** were 50,60,and 30 cm,*** infiltration characters were simulated by the Kostiakov equations,and the simulated and experimental results were *** regression revealed that vegetation types and soil bulk density had significant effects on soil initial infiltration rate during the four study periods,and the infiltration rate of the period 1 year after mining was mainly influenced by the soil bulk density of the period before *** results indicated that vegetation types had significant effects on soil bulk density,and that the tree-shrub-grass mode was better than one single plantation for water conversation and vegetation recovery in sandy land subjected to mining.

关键词： soil bulk density soil infiltration rate Sandy land Vegetation type

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Monitoring of soil bulk density in Context with Its Small-Scale Spatial Heterogeneity

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Journal of Geoscience and Environment Protection 2021年第5期9卷 138-151页

作者： Miloš Širáň Jarmila Makovníková National Agricultural and Food Centre Soil Science and Conservation Research Institute Bratislava Slovakia

The main aim of soil monitoring system is to obtain the knowledge of the most current state and development of soil properties according to concrete threats to soil. To determine the significant changes of soil properties in time, it is important to know spatial variability of concrete soil parameter for concrete site. Only those time changes of the soil parameter are significant, which exceed its spatial variability at the site. The main aim of the study has been focused on the evaluation of small-scale site heterogeneity of equilibrium soil bulk density and the integration of impact of this heterogeneity in evaluation of degradation process of soil compaction in time. As site variation coefficients have considerably varied at standard sampling with five repetitions during monitoring period, one-time detail spatial variability mapping of soil bulk density was realized at 17 repetitions on five selected monitoring sites with different soil type, texture and use. This increase in the number of sampling points helped us to specify and stabilize the values of variation coefficients (between minimum and maximum by standard sampling) as well as the extent of confidence intervals. Standard deviations at the chosen monitoring sites moved from 0.039 to 0.118 g·cm-3 in topsoil and from 0.031 to 0.067 g·cm-3 in subsoil and expressed as variation coefficient 2.9% - 9.2% and 2.0% - 4.9%, respectively. The intervals of significant time changes of soil bulk density for the sites and depths were determined on the base of its site confidence interval (9

关键词： soil Monitoring soil bulk density Spatial Site and Time Variability Significant Time Change

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Diffusion of Chloride Ions in soils:*** of soil Moisture, bulk density and Temperature

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Pedosphere 1997年第1期7卷 65-72页

作者： XU MINGGANG, ZHANG YIPING and LIU WEINING (Department of soil Science and Agrochemistry, Northwestern Agricultural University, Yangling, Shaanxi 712100 China) Department of soil Science and Agrochemistry Northwestern Agricultural University Yangling Shaanxi 712100 China

Diffusion coefficients of chloride ions in four soils of different texture with varying effective moisture content and varying bulk density from 1.1 to 1.6 g cm3 under three different temperatures were determined by the diffusion-cell method using 36Cl-labelled CaCl2 solution. The results showed that activation energy decreased with water content, which indicated that the threshold for diffusion was lower at a higher soil moisture rate. Therefore, the diffusion coefficient (D) of chloride ions in soil increased consistently with soil moisture. Although a near linear increase in the diffusion coefficient with increasing soil moisture or bulk density in all the soils was observed, the increase rate in different soils was not the same. The D value increased with temperature, and with temperature increased by 10℃ in the range from 5 "C to 45℃ theD valve increased by 10%～30%, averaging about 20%.

关键词： chloride ion diffusion coefficient soil bulk density soil moisture temperature

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Vertical distribution characteristics of soil organic carbon content in Caohai wetland ecosystem of Guizhou plateau, China

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Journal of Forestry Research 2016年第3期27卷 551-556页

作者： Yunjie Wu Fengyou Wang Sixi Zhu Northeast Forestry University Harbin 150040 China Guizhou Minzu University Guiyang 550025 China

We selected four kinds of land use types from Caohai wetlands of Guizhou plateau（a total number of 32 soil profiles） to study the distribution characteristics of organic carbon content in soil. With different ways of land use, the organic carbon content of soil profiles and organic carbon density show the tendency of decreasing firstly and then increasing from top to bottom. With the increase of depth, the vertical difference becomes smaller first and then starts increasing. Land reclamation reduces the soil organic carbon content and density, changing its distribution structure in topsoil. The average content of organic carbon in Caohai wetlands are as follows： lake bed silt [ marsh wetland [ farmland [ woodland, the average organic carbon content of lake bed silt, marsh wetland,farmland and woodland are 16.40, 2.94, 1.81 and 1.08 %,respectively. Land reclamation reduces the organic carbon content of soil, therefore the conversion of cultivated lands to wetlands and the increase of forest coverage will help to fix the organic carbon in soil and increase its reserves.

关键词： Land using pattern Wetlands soil organiccarbon soil bulk density

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Changes in soil organic carbon,nitrogen and sulphur along a slope gradient in apple orchard soils of Kashmir Himalaya

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Journal of Mountain Science 2021年第9期18卷 2377-2387页

作者： Javaid M DAD Lotfollah ABDOLLAHI Department of Botany University of KashmirHazratbalSrinagar(J&K)India Faculty of Agriculture Payame Noor UniversityTehranP.O.Box 19395-3697Iran

Accumulation and losses of soil organic carbon(SOC),total nitrogen(TN)and sulphur(S)influence food security and global ***,their spatial distribution and variability at regional scale,and their relation to topographical variables are of great *** this study,the variability of SOC,TN and S content was evaluated in apple orchard soils of Kashmir region,at three depths(D1:0-10,D2:10-20,and D3:20-30 cm)on slope gradient i.e.:flat,medium,and *** an increase in slope,a significant decrease of SOC and TN was observed,with concentration of SOC and TN recorded highest(14.3±2.06 g kg-1&0.97±0.35 g kg-1)in flat slope orchards and lowest(9.6±2.07 g kg-1&0.84±0.41 g kg-1)in high slope *** stock basis,the values recorded for flat,medium,and high slope orchards,for SOC and TN were 54.62±4.24 Mg ha-1&0.38±0.06 Mg ha-1,44.13±5.11 Mg ha-1&0.32±0.09 Mg ha-1,and 38.73±5.94 Mg ha-1&0.28±0.10,*** differences for S concentration and stocks were modest,with flat(0.21±0.15 mg kg-1&0.09±0.0.003 Mg ha-1)>high(0.16±0.07 mg kg-1&0.06±0.007 Mg ha-1)>medium(0.12±0.04 mg kg-1&0.075±0.009 Mg ha-1).Across slopes,SOC,TN and S decreased with increasing soil depth,suggesting clear downward ***,SOC and TN increased with the increase of altitude,precipitation and clay content while its relationship with soil acidity and soil bulk density was *** findings may provide scientific basis to structure agricultural development plans or prioritize regions for soil conservation efforts.

关键词： Apple orchards Slope soil organic carbon Sulphur Total nitrogen soil bulk density

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Effect of Rotational Tillage on soil Aggregates, Organic Carbon and Nitrogen in the Loess Plateau Area of China

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Pedosphere 2013年第4期23卷 542-548页

作者： HOU Xian-Qing LI Rong JIA Zhi-Kuan HAN Qing-Fang Chinese Institute of Water-Saving Agriculture Northwest A&F University Key Laboratory of Crop Physi-Ecology and Tillage Science in Northwestern Loess Plateau Ministry of Agriculture Northwest A&F University School of Agriculture Ningxia University

In rain-fed semi-arid agroecosystems, continuous conventional tillage can cause serious problems in soil quality and crop production, whereas rotational tillage （no-tillage and subsoiling） could decrease soil bulk density, and increase soil aggregates and organic carbon in the 0-40 cm soil layer. A 3-year field study was conducted to determine the effect of tillage practices on soil organic carbon （SOC）, total nitrogen （TN）, water-stable aggregate size distribution and aggregate C and N sequestration from 0 to 40 cm soil in semi-arid areas of southern Ningxia. Three tillage treatments were tested： no-tillage in year 1, subsoiling in year 2, and no-tillage in year 3 （NT-ST-NT）; subsoiling in year 1, no-tillage in year 2, and subsoiling in year 3 （ST-NT-ST）; and conventional tillage over years 1-3 （CT）. Mean values of soil bulk density in 0-40 cm under NT-ST-NT and ST-NT-ST were significantly decreased by 3.3% and 6.5%, respectively, compared with CT, while soil total porosity was greatly improved. Rotational tillage increased SOC, TN, and water-stable aggregates in the 0-40 cm soil, with the greatest effect under ST-NT-ST. In 0-20 and 2（}-40 cm soils, the tillage effect was confined to the 2-0.25 mm size fraction of soil aggregates, and rotational tillage treatments obtained significantly higher SOC and TN contents than conventional tillage. No significant differences were detected in SOC and TN contents in the 〉 2 mm and 〈 0.25 mm aggregates among all treatments. In conclusion, rotational tillage practices could significantly increase SOC and TN levels, due to a fundamental change in soil structure, and maintain agroecosystem sustainability in the Loess Plateau area of China.

关键词： semi-arid region SOC sorage soil bulk density tillage practice water-stable aggregates

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soil Hydraulic Properties： Influence of Tillage and Cover Crops

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Pedosphere 2018年第3期28卷 430-442页

作者： Samuel I. HARUNA Stephen H. ANDERSON Nsalambi V. NKONGOLO Syaharudin ZAIBON School of Agriculture College of Basic and Applied Sciences Middle Tennessee State University 1301 East Main Street Murfreesboro TN 37132-0001( USA) Department of soil Environmental and Atmospheric Sciences 302 Anheuser-Busch Natural Resources Building University of Mis-souri Columbia MO 65211-0001( USA) Institut Facultaire des Sciences Agronomiques (IFA-Yangambi) Boite Postale Kisangani 1232( Democratic Republic of Congo) Department of Land Management Faculty of Agriculture University Putra Malaysia 43400 Serdang Selangor Malaysia

Understanding the effects of cover crops and tillage on soil physical properties is important for determining soil productivity. This study was conducted at Lincoln University＇s Freeman Center, USA to evaluate the effects of tillage and cover crop management on soil hydraulic properties. The field site included three replicate blocks in a randomized complete block design with each plot measuring 21.3 m in length and 12.2 m in width. Treatment factors were tillage at two levels （moldboard plow tillage vs. no tillage） and cover crop at two levels （cereal rye （Secale cereal） cover crop vs. no cover crop）. soil samples were collected in late spring/early summer from each treatment at 10-cm depth increments from the soil surface to a depth of 40 cm using cores （76.2-mm diameter and 76.2-mm length）. soil bulk density was 13% lower with tillage compared with no-tillage. Volumetric water content was significantly higher at 0.0 and -0.4 kPa pressures with tillage compared with no tillage. Tillage increased the proportion of coarse mesopores by 32gc compared with no tillage, resulting in 87% higher saturated hydraulic conductivity （Ksat）. Cover crop increased the proportion of macropores by 24~ compared with no cover crop; this can potentially increase water infiltration and reduce runoff. As a result of higher macroporosity, Ksat was higher under cover crop compared with no cover crop. This study demonstrated that tillage can benefit soil hydraulic properties in the short term, but these effects may not persist over time. Cover crops may slightly improve soil hydraulic properties, but longer term studies are needed to evaluate the long-term effects.

关键词： pore size distribution saturated hydraulic conductivity soil bulk density soil water retention volumetric water content

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On Designing Biopolymer-Bound soil Composites (BSC) for Peak Compressive Strength

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Journal of Renewable Materials 2020年第8期8卷 845-861页

作者： Isamar Rosa Henning Roedel Maria I.Allende Michael D.Lepech David J.Loftus Department of Civil and Environmental Engineering Stanford UniversityStanfordCA 94305USA Division of Space Biosciences NASA Ames Research CenterMoffet FieldCA 94035USA

Biopolymer-bound soil Composites(BSC),are a novel bio-based construction material class,produced through the mixture and desiccation of biopolymers with inorganic aggregates with applications in soil stabilization,brick creation and in situ construction on Earth and *** paper introduces a mixture design methodology to produce maximum strength for a given soil-biopolymer *** protein and sand mix designs were investigated,with varying amounts of biopolymer solution and compaction regimes during *** ultimate compressive strength,density,and shrinkage of BSC samples are *** is observed that the compressive strength of BSC materials increases proportional to tighter particle packing(soil dry bulk density)and binder content.A theory to explain this peak compressive strength phenomenon is presented.

关键词： Compressive strength biopolymer composites material design soil bulk density in situ material utilization sustainable materials

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soil micromorphological and physical properties after application of composts with polyethylene and biocomponent-derived polymers added during composting

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Pedosphere 2021年第4期31卷 560-571页

作者： Monika MIERZWA-HERSZTEK Krzysztof GONDEK Altaf Hussain LAHORI MichałKOPEĆ Ryszard MAZUREK Tomasz ZALESKI Tomasz GŁ˛AB Jerzy WIECZOREK Department of Agricultural and Environmental Chemistry University of Agriculture in Krakowal.Mickiewicza 21Krakow 31-120(Poland) Department of Mineralogy Petrography and GeochemistryAGH University of Science and Technologyal.Mickiewicza 30Krakow 30-059(Poland) Department of Environmental Sciences Sindh Madressatul Islam UniversityKarachi 74000(Pakistan) Department of soil Science and soil Protection University of Agriculture in Krakowal.Mickiewicza 21Krakow 31-120(Poland) Institute of Machinery Exploitation Ergonomics and Production ProcessesUniversity of Agriculture in Krakowul.Balicka 116BKrakow 31-149(Poland)

Composts are considered to be one of the best soil amendments. However, the effects of composts with added polymeric materials on soil physical,hydraulic, and micromorphological properties have not been widely discussed. Changes in soil physical properties influence the numerous services that soils provide. We studied the impacts of composts with the addition of three different polymers(F1–F3) produced from polyethylene and thermoplastic corn starch on the physical, hydraulic, and micromorphological properties of two soils, a Cambic Phaeozem and a Luvic Phaeozem. Applying composts with polymers had limited or no significant effect on soil bulk density and porosity, but increased the field water capacity by 18%–82% and 3%–6% and the plant-available water content by 15%–23% and 4%–17% for the Cambic Phaeozem and Luvic Phaeozem, respectively. The application of composts with polymers had a greater effect on the Cambic Phaeozem than on the Luvic Phaeozem. It was suggested that the use of modified composts led to changes in soil physical properties and micromorphological features and this effect was dependent on the compost application rate. Composts made with the addition of composite synthetic and natural material-derived polymers during composting were found to be a composite mixture that can be successfully used in agriculture.

关键词： composite mixture corn starch field water capacity plant-available water content porosity soil bulk density soil micromorphology soil water retention

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Spatial Variability of soil Organic Carbon Under Maize Monoculture in the Song-Nen Plain, Northeast China

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Pedosphere 2010年第1期20卷 80-89页

作者： WANG Zong-Ming , ZHANG Bai, SONG Kai-Shan, LIU Dian-Wei and REN Chun-Ying Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012 (China) [a] Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 (China)

soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils, Cambisol, Arenosol, Phaeozem, and Chernozem, were collected at 451 locations in Nongan County under maize monoculture in the Song-Nen Plain, Northeast China. The spatial characteristics of soil organic carbon were studied, using geographic information systems (GIS) and geostatistics. Effects of other soil physical and chemical properties, elevation, slope, and soil type on SOC were explored. SOC concentrations followed a normal distribution, with an arithmetic mean of 14.91 g kg-1 . The experimental variogram of SOC was fitted with a spherical model. There were significant correlations between soil organic carbon and bulk density (r =-0.374**), pH (r = 0.549**), total nitrogen (r = 0.781**), extractable phosphorus (r =-0.109*), exchangeable potassium (r = 0.565**), and cation exchange capacity (r = 0.313**). Generally, lower SOC concentrations were significantly associated with high elevation (r =-0.429**). soil organic carbon was significantly negatively correlated with slope gradient (r =-0.195**). Samples of the Cambisol statistically had the highest SOC concentrations, and samples of the Arenosol had the lowest SOC value.

关键词： geostatistics slope soil bulk density spatial distribution

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