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Relating thermal conductivity of soil skeleton with Soil texture by the concept of“local thermal conductivity fluctuation”

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 262-271页

作者： Adrian Rózanski Faculty of Civil Engineering Wroclaw University of Science and TechnologyWybrzeze Wyspia_nskiego 2750-370WrocławPoland

The thermal conductivity of the soil skeletonλ;is an essential parameter from the point of view of the correct assessment of soil overall/effective conductivity.This work introduces the concept of“local thermal conductivity fluctuation”which characterizes the microscale variation of conductivity within the solid phase.It is proposed to link the“local fluctuation”of thermal conductivityλwith the Soil texture-the information that is available at the scale of engineering applications.It was possible to relate the skeleton thermal conductivity with the grain size distribution of the soil.Finally,based on a large series of numerical simulations,the paper provides four triangle diagrams(at different organic matter contents:0%,2%,4%and 6%)relating the value ofλ;with volume fraction of individual soil separates.This result is extremely important from the practical point of view.One can quickly evaluateλ;value provided that information on the grain size distribution and organic matter content is available.

关键词： soil skeleton Probability density function(PDF) Computational micromechanics Local fluctuation Soil texture

In-situ Soil texture classification and physical clay content measurement based on multi-source information fusion

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International Journal of Agricultural and Biological Engineering 2023年第1期16卷 203-211页

作者： Chao Meng Wei Yang Xinjian Ren Dong Wang Minzan Li Key Lab of Smart Agriculture Systems Ministry of EducationChina Agricultural UniversityBeijing 100083China

Soil texture is one of the most important soil characteristics that affect soil properties.Rapid acquisition of Soil texture information is of great significance for accurate farmland management.Traditional Soil texture analysis methods are relatively complicated and cannot meet the requirements of temporal and spatial resolution.This research introduced a self-developed vehicle-mounted in-situ Soil texture detection system,which can predict the type of Soil texture and the particle composition of the texture,and obtain real-time data during the measurement process without preprocessing the soil samples.The detection system is mainly composed of a conductivity measuring device,a camera,an auxiliary mechanical structure,and a control system.The soil electrical conductivity(ECa)and the texture features extracted from the surface image were input into the embedded model to realize real-time texture analysis.In order to find the best model suitable for the detection system,measurements were carried out in three test fields in Northeast and North China to compare the performance of different models applied to the detection system.The results showed that for Soil texture classification,ExtraTrees performed best,with Precision,Recall,and F1 all being 0.82.For particle content of Soil texture prediction,the R2 of ExtraTrees was 0.77,and RMSE and MAPE were 74.72 and 39.58.It was observed that ECa,Moment of inertia,and Entropy had larger weights in the drawn model influence weight map,and they are the main contributors to predicting Soil texture.These results showed the potential of the vehicle-mounted in-situ Soil texture detection system,which can provide a basis for fast,cost-effective,and efficient Soil texture analysis.

关键词： Soil texture soil sensor electrical conductivity soil surface image

Influence of Soil texture on the process of subsurface drainage in saturated-unsaturated zones

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International Journal of Agricultural and Biological Engineering 2021年第1期14卷 82-89页

作者： Yufang Li Mingsi Li Hongguang Liu Wenbao Qin College of Water Resources and Architectural Engineering Shihezi UniversityShihezi 832000XinjiangChina Santunhe River Basin Management Section Changji Water Resources BureauChangji 831100XinjiangChina

This study addressed the problem of low drainage efficiency or even no drainage in subsurface drainage systems buried in saturated-unsaturated zones above the water table.An indoor experiment on infiltration under ponded conditions in a homogeneous soil column was performed to study the effects of Soil texture on the soil wetting front morphology,soil infiltration rate,drainage efficiency of the subsurface drainage pipe,vertical distribution of soil water content and salinity along the soil column.The results showed that the drainage process of subsurface drainage pipes above the water table was quite different from that of subsurface drainage pipes below the water table.When a subsurface drainage pipe was located in sandy soil,the migration of soil water toward the bottom of the drainage pipe was significant,and the water could not be discharged into the pipe.When the drainage pipe was located in loamy clay,the movement of soil water towards the bottom of the pipe was retarded,and the water could be discharged into the pipe.During the drainage process,the drainage of the pipe can produce nonequilibrium flow in the soil,and the continuity of the nonequilibrium flow can be affected by the hydraulic conductivity of the soil above the pipe,which can result in discontinuous drainage and low drainage efficiency.The water holding capacity,permeability and aeration of soil are important factors that affect the drainage under unsaturated conditions.Eliminating the hysteresis effect and capillary barrier around the drainage pipe and adjusting water holding capacity,the permeability and aeration of soil structure through a new subsurface drainage structure may enhance the drainage efficiency of subsurface drainage pipes in saturated-unsaturated zones.

关键词： saturated-unsaturated zone Soil texture subsurface drainage pipe groundwater level

Effects of Soil texture on the Growth of Young Apple Trees and soil Microbial Community Structure Under Replanted Conditions

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Horticultural Plant Journal 2020年第3期6卷 123-131页

作者： Yuefan Sheng Haiyan Wang MeiWang Hanhao Li Li Xiang Fengbing Pan Xuesen Chen Xiang Shen Chengmiao Yin Zhiquan Mao College of Horticultural Science and Engineering/State Key Laboratory of Crop Biology Shandong Agricultural UniversityTai’anShandong 271018China College of Resources and Environment Shandong Agricultural UniversityNational Engineering Laboratory for Efficient Utilization of Soil and Fertilizer ResourcesTai’anShandong 271018China

A two-year field experiment was carried out in order to study the occurrence degree and mechanism of apple replant disease(ARD)in the apple orchards with different Soil textures.So we can adopt appropriate controlmeasures according to the severity of ARD.Healthy two-year-old seedlings with consistent growth were selected,of which the root stock was T337 and the scion was Yanfu 3.There were significant differences in biomass between methyl bromide fumigation and replanted treatments,and the difference was the largest in clay loam,followed by sandy loam,and loam,which verified ARD in clay loam was most serious,followed by sandy loam and loam.Based on high-throughput sequencing of fungi in soil samples,fungal richness and diversity were the highest in clay loam,followed by sandy loam,and loam.The relative abundance of Fusarium in SX,SL,FX,FL,WX and WL was 7.33%,19.32%,2.70%,4.24%,10.71%and 23.87%,respectively.Based on Real-time quantitative analysis,there were significant differences in the number of Fusarium oxysporum and Fusarium solani between methyl bromide fumigation and replanted treatments,i.e.,clay loam>sandy loam>loam.Fusarium was the main pathogen causing ARD.This shows that ARD is the most serious under replanted clay loam condition.High-throughput sequencing technology was used to prove the difference in Fusarium was one of the important reasons for ARD under different Soil textures.This technology provides a new idea for the prevention and control of ARD.

关键词： Apple Apple replant disease Fungi community structure Soil texture High-throughput sequencing

Mapping the vertical distribution of maize roots in China in relation to climate and Soil texture

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Journal of Plant Ecology 2018年第6期11卷 899-908页

作者： Sheng Wang Yao Huang Wenjuan Sun Lingfei Yu State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences20 NanxincunXiangshanBeijing 100093China University of Chinese Academy of Sciences No.19 Yuquan RoadShijingshan DistrictBeijing 100049China

Aims Optimizing water and fertilizer management for crops requires an understanding of root distribution.Maize(Zea mays L.)is currently the most widely planted cereal crop in China,yet the vertical dis-tribution of maize roots across different regions remains unknown.The aims of this work were(i)to quantify the effects of climate and Soil texture on the vertical distribution of maize roots,and(ii)to show the depth distribution of root biomass in China.Methods We used data of maize root biomass from 11 Chinese ecological stations with discontinuous observations from 2004 to 2014 to fit the regression coefficientβfor an asymptotic equation Y=1-βd,where d is the soil depth and Y is the proportion of root biomass from the surface to depth d.A statistical model was then developed to quantify the effects of climate and Soil texture on the fittedβval-ues.Using the statistical model,we map the depth distribution of maize root biomass in China.Important Findings Maize root biomass in the 0-100 cm soil depth varied by an order of magnitude at different stations,from 64 to 268 g m−2.Maize planted in sandy soils and/or maize with high accumu-lated temperature for development had higher root biomass and deeper rooting systems.The fittedβvalues ranged from 0.785 to 0.977,which can be modeled by an integration of the accu-mulated temperature during the maize growing period and the soil clay and sand fractions(R2=0.66,n=50,Psoil layers,respectively.Deeper rooting systems occurred in some temperate arid and temperate semi-arid regions,with less than 80%of the root bio-mass in the top 20 cm soil.Our findings highlighted the vertical distribution of maize roots,and underlined the spatial variability in the vertical distribution of roots across China’s planting areas of maize.

关键词： accumulated temperature maize root Soil texture statistical model vertical distribution

Characterization of an Area Polluted by Copper and Zinc:the Relation between Soil texture,Mineralogy and Pollutant Concentration

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Acta Geologica Sinica(English Edition) 2009年第6期83卷 1224-1231页

作者： Caterina RINAUDO Daniela GASTALDI Orfeo ZERBINATI Elisa FORNERO Graziella BERTA Department of Environmental and Life Sciences University of Eastern Piedmont

Twenty-four soil samples were collected at three depths from an approximately 2.5 acre contaminated site in southern Piedmont （Italy） and then analyzed. The main soil parameters determined were： pH, Cation Exchange Capacity （CEC）, particle size distribution, total organic carbon （TOC） content and retained metal concentration. The mineral phases were identified by X-Ray Powder Diffraction （XRPD）. All of the samples contained Zn and Cu resulting from industrial contamination during the last century, and those obtained at depths of 20-40 cm consistently showed the highest levels. To determine which size fraction was most active in the retention process, the samples were separated into four fractions （≤2 mm, ≤63 0m, ≤30 0m and ≤2 μm） and the amount of pollutant measured in each. It was found that metal retention was the highest in the clayey fraction, whose clay minerals were identified by XRPD after K＋ and Mg2＋ saturation, glycerol treatment and heating to 550℃. The clayey fraction was also the richest in TOC, and a direct correlation between TOC amount and metal retention was observed.

关键词： soil pollution heavy metals Soil texture clay minerals

Effect of Soil texture on Starch Accumulation and Activities of Key Enzymes of Starch Synthesis in the Kernel of ZM 9023

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Agricultural Sciences in China 2008年第6期7卷 686-691页

作者： WANG Wen-jing ZHAN Hai-hong Department of Medicinal Engineering Zhengzhou Animal Husbandry Engineering College Zhengzhou 450011 P.R.China Department of Biochemistry Pingdingshan Educational College Pingdingshan 467000 P.R.China

Three kinds of Soil texture （clay-loam, mid-loam, and sand-loam soil） were used to study the effects of Soil texture on starch accumulating rate and the changes in activities of the key enzymes of starch synthesis in the kernel during grain filling in high gluten content wheat ZM 9023, under conditions of pond culture. The content of starch and its components were measured according to the method of double-wave length described by Bao （1996）. ADP-glucose pyrophosphorylase （AGPP） activity was tested according to the method described by Doehlert et al. （1988）. Soluble starch synthase （SSS） and starch branching enzyme （SBE） activities were tested according to the method described by Nakamura et al. （1989）. The amylose, amylopectin, and total starch accumulating rate in the kernel of ZM 9023 were found to be a single-peak curve in three different Soil textures during grain filling, and peaked 20, 15, and 15 d after anthesis, respectively. The activities of the enzymes, AGPP, SSS, and SBE, in the kernel of ZM 9023 had a single-peaked curve, which peaked 20, 15, and 15 d after anthesis, respectively. The activities of the above three enzymes of ZM 9023 were higher in the sand-loam soil. The accumulating peak of amylose formed later compared to that of amylopectin. The sand-loam soil could help high gluten content cultivars to synthesize starch.

关键词： wheat （Triticum aestivum L.） Soil texture gluten content starch enzyme

Possibility of avoiding legumes-deriving boost of N 2 O emissions in tropical monoculture tree plantations

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Journal of Forestry Research 2023年第2期34卷 565-573页

作者： Taiki Mori Chongrak Wachrinrat Duriya Staporn Ryota Aoyagi Ponthep Meunpong Warawich Suebsai Khitja Boonsri Kanehiro Kitayama Forest Ecology Laboratory Graduate School of AgricultureKyoto UniversityKitashirakawa Oiwake-cho Sakyo-kuKyoto 606-8502Japan Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650GuangdongPeople’s Republic of China Forestry and Forest Products Research Institute FFPRI 1 MatsunosatoTsukubaIbaraki 305-8687Japan Faculty of Forestry Kasetsart UniversityChatuchakBangkok 10900Thailand Smithsonian Tropical Research Institute Bocas TownIsla AncónRepublic of Panama

Recent reports warned that planting leguminous trees under monocultures elevates nitrous oxide(N2O)emissions through N-rich litter inputs.We hypothesized that planting trees on sandy soil can avoid the legume-derived boost of N2O emissions through limiting water availability for N2O production.Effects of planting legumes on methane(CH4)uptakes were also examined.N2O emissions and CH4uptakes were compared among five tropical tree plantation stands including three leguminous stands(Acacia auriculiformis,Acacia mangium,and Xylia xylocarpa)and two non-leguminous stands(Eucalyptus camaldulensis,and Hope a odorata).Due to lower water contents of the soil,the N2O fluxes in our study site were at the lower end of the tropical rain forests.As we hypothesized,no clear differences in N2O emissions were obs erved between leguminous and non-leguminous stands.CH4uptake rates in the present study were lower than those of other tropical forests.CH4uptakes in leguminous stands did not differ from those in non-leguminous stands.Overall,we demonstrated that planting leguminous trees on sandy soils has a potential to enable us to manage leguminous monoculture tree plantations without boosting N2O emissions or reducing CH4uptakes.

关键词： Nitrous oxide Methane Fast-growing trees Tropical forest Soil texture

soil organic carbon storage in forest restoration models and environmental conditions

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Journal of Forestry Research 2022年第4期33卷 1123-1134页

作者： Ranieri Ribeiro Paula Miguel Calmon Maria Leonor Lopes-Assad Eduardo de SáMendonça Departamento de Agronomia Programa de Pós-Graduação em Produção VegetalUniversidade Federal do Espírito SantoAlto UniversitárioGuararemaAlegreEspírito Santo CEP 29500-000Brazil World Resources Institute SalvadorBahia CEP 40290-040Brazil Departamento de Recursos Naturais e Proteção Ambiental Universidade Federal de São CarlosArarasSão Paulo CEP 13600-970Brazil

The scale of forest and landscape restoration is expected to increase during the UN Decade on Ecosystem Restoration and its contribution to the provision of critical ecosystem services to society.Several models of forest restoration may improve ecosystem services,including soil organic carbon(SOC)storage.A review was carried out to access:(1)the variability of SOC storage between worldwide forest restoration models and,(2)the effects of climate,soil class,Soil texture,and vegetation type on SOC storage.We reviewed 119 primary studies with information on SOC and Soil texture for different forest restoration models.The restoration models were grouped into four categories:natural regeneration,monocultures,agroforestry,and mixed forest.SOC data was extracted from these four restoration models,other land uses(cropland,bare land,grassland,and natural forest),climate regimes,and soil properties.The SOC storage in the forest restoration models and other land uses at a global scale ranged between 0.1 to 514 Mg ha^(-1).The overall mean value for SOC storage was higher for natural regeneration(112 Mg ha^(-1)),followed by agroforestry(74 Mg ha^(-1)),mixed forest(73 Mg ha^(-1)),and monocultures(68 Mg ha^(-1)).However,the average SOC storage was similar among the four restoration models in the moist warm climate zone.The SOC storage mean value in the moist cool zone was 23%higher than the dry cool zone(81 and 62 Mg ha^(-1),respectively),and 50%higher for the moist warm zone when compared to the dry warm climatic zone(74 and 38 Mg ha^(-1),respectively).The SOC storage of the restoration models was positively related to soil depth(0.59;psoils showed smaller mean values of SOC storage than medium to clay soils,especially in deeper soil layers.Furthermore,SOC storage was positively related between restoration models and other land

关键词： Forest restoration Land uses soil type Soil texture Climate