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Quantitative analysis of yield and soil water balance for summer maize on the piedmont of the North China

Jingjing WANG,Feng HUANG,Baoguo LI

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 295-310 doi: 10.15302/J-FASE-2015074

摘要： The North China Plain (NCP) is a major grain production area in China, but the current winter wheat-summer maize system has resulted in a large water deficit. This water-shortage necessitates the improvement of crop water productivity in the NCP. A crop water model, AquaCrop, was adopted to investigate yield and water productivity (WP) for rain-fed summer maize on the piedmont of the NCP. The data sets to calibrate and validate the model were obtained from a 3-year (2011–2013) field experiment conducted on the Yanshan piedmont of the NCP. The range of root mean square error (RMSE) between the simulated and measured biomass was 0.67–1.25 t·hm , and that of relative error (RE) was 9.4%–15.4%, the coefficient of determination ( ) ranged from 0.992 to 0.994. The RMSE between the simulated and measured soil water storage at depth of 0–100 cm ranged from 4.09 to 4.39 mm; and RE and in the range of 1.07%–1.20% and 0.880–0.997, respectively. The WP as measured by crop yield per unit evapotranspiration was 2.50–2.66 kg·m . The simulated impact of long-term climate (i.e., 1980–2010) and groundwater depth on crop yield and WP revealed that the higher yield and WP could be obtained in dry years in areas with capillary recharge from groundwater, and much lower values elsewhere. The simulation also suggested that supplementary irrigation in areas without capillary groundwater would not result in groundwater over-tapping since the precipitation can meet the water required by both maize and ecosystem, thus a beneficial outcome for both food and ecosystem security can be assured.

关键词： AquaCrop     summer maize     soil water balance     water productivity    

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Assessment of future climate change impacts on water-heat-salt migration in unsaturated frozen soil using

Hanli Wan, Jianmin Bian, Han Zhang, Yihan Li

《环境科学与工程前沿（英文）》 2021年 第15卷 第1期 doi: 10.1007/s11783-020-1302-5

摘要： Abstract • A model coupling water-heat-salt of unsaturated frozen soil was established. • Future temperature, precipitation, and evaporation increase in freeze–thaw period. • Soil water, heat, and salt transport are closely coupled during freeze–thaw period. • Freeze–thaw cycles and future climate change can exacerbate salinization. The transport mechanisms of water, heat, and salt in unsaturated frozen soil, as well as its response to future climate change are in urgent need of study. In this study, western Jilin Province in north-eastern China was studied to produce a model of coupled water-heat-salt in unsaturated frozen soil using CoupModel. The water, heat, and salt dynamics of unsaturated frozen soil under three representative concentration pathway (RCP) scenarios were simulated to analyze the effects of future climate change on unsaturated frozen soil. The results show that water, heat, and salt migration are tightly coupled, and the soil salt concentration in the surface layer (10 cm) exhibits explosive growth after freezing and thawing. The future (2020–2099) meteorological factors in the study area were predicted using the Statistical Downscaling Model (SDSM). For RCP2.6, RCP4.5, and RCP8.5 scenarios, future temperatures during the freeze–thaw period increased by 2.68°C, 3.18°C, and 4.28°C, respectively; precipitation increased by 30.28 mm, 28.41 mm, and 32.17 mm, respectively; and evaporation increased by 93.57 mm, 106.95 mm, and 130.57 mm, respectively. Climate change will shorten the freeze–thaw period, advance the soil melting time from April to March, and enhance water and salt transport. Compared to the baseline period (1961–2005), future soil salt concentrations at 10 cm increased by 1547.54 mg/L, 1762.86 mg/L, and 1713.66 mg/L under RCP2.6, RCP4.5, and RCP8.5, respectively. The explosive salt accumulation is more obvious. Effective measures should be taken to prevent the salinization of unsaturated frozen soils and address climate change.

关键词： Soil salinization     Climate change     Unsaturated frozen soil     Water-heat-salt balance     Soil environment change    

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Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

《机械工程前沿（英文）》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0676-4

摘要： The control system presently used in shield posture rectification is based on driver experience, which is marginally reliable. The study of the related theory is flawed. Therefore, a decision-making approach for the deviation correction trajectory and posture rectification load for an earth pressure balance (EPB) shield is proposed. A calculation model of posture rectification load of an EPB shield is developed by considering the interactions among the cutter head, shield shell, and ground. The additional position change during the shield attitude correction is highlighted. The posture rectification loads and shield behaviors results can be solved by the proposed method. The influences of the stratum distribution (i.e., bedrock height in the upper-soft and lower-hard strata) on shield behaviors and posture rectification loads are analyzed. Results indicated that the increase of pitch angle in the upper-soft and lower-hard strata causes a sharp rise in vertical displacement. The bedrock height increases the magnitudes of the required posture rectification moments when hr/D > 0.5. For a tunnel with hr/D ≤ 0.5, the variation of hr/D has little effect on the posture rectification moments. Finally, the posture rectifying curves based on the theoretical model are compared with the target ones based on the double circular arc interpolation method. The required results can be obtained regardless of the soil–rock compound stratum distribution. The maximum rectification moment in the rock layer is almost 12.6 times that in the soil layer. Overall, this study provides a valuable reference for moment determination and the trajectory prediction of posture rectification in compound strata.

关键词： additional position change     deviation correction trajectory     earth pressure balance shield     mechanical model     posture rectification    

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Experimental study on the stratum applicability and mechanisms of bubble–slurry for earth pressure balance

《结构与土木工程前沿（英文）》   页码 1387-1399 doi: 10.1007/s11709-023-0005-y

摘要： Soil conditioning is essential for addressing the stratum applicability problem of earth pressure balance (EPB) shields. Under high water pressures, EPB shields spew water and soil when excavating coarse-grained strata. Typically, foam combined with polymers and slurry is used to solve spewing. However, in current techniques, slurry, foam, and the other agents are mixed with soil separately, their synergistic effect is seldom realized. In this study, an anionic surfactant was used to foam in bentonite slurry to form bubble–slurry to maximize the synergy between bubbles and slurry. The slump, volume stability, and permeability test of bubble–slurry-conditioned sand was conducted to examine the conditioning effect, and the stratum applicability of bubble–slurry was determined from the perspective of permeability. It was found that the conditioning effect of bubble–slurry in coarse gravel soil was excellent and could expand the applicability of EPB shields. The main stabilization mechanism of bubble–slurry is that bentonite particles provide a space barrier for bubbles. And three seepage modes of bubble–slurry-conditioned sand were innovatively defined, and the occurrence conditions of the three seepage modes were analyzed according to the permeability coefficient of sand, initial dynamic shear force of bubble–slurry, and hydraulic gradient.

关键词： EPB shield     bubble–slurry     soil conditioning     stability     permeability    

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LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE -2020349

摘要：

Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

 

关键词： crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

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Soil-water interaction in unsaturated expansive soil slopes

ZHAN Liangtong

《结构与土木工程前沿（英文）》 2007年 第1卷 第2期   页码 198-204 doi: 10.1007/s11709-007-0023-1

摘要： The intensive soil-water interaction in unsaturated expansive soil is one of the major reasons for slope failures. In this paper, the soil-water interaction is investigated with the full-scale field inspection of rainwater infiltration and comprehensive experiments, including wetting-induced softening tests, swelling, and shrinkage tests. It is demonstrated that the soil-water interaction induced by seasonal wetting-drying cycles is very complex, and it involves coupled effects among the changes in water content, suction, stress, deformation and shear strength. In addition, the abundant cracks in the expansive soil play an important role in the soil-water interaction. The cracks disintegrate the soil mass, and more importantly, provide easy pathways for rainfall infiltration. Infiltration of rainwater not only results in wetting-induced softening of the shallow unsaturated soil layers, but also leads to the increase of horizontal stress. The increase of horizontal stress may lead to a local passive failure. The seasonal wetting-drying cycles tend to result in a down-slope creeping of the shallow soil layer, which leads to progressive slope failure.

关键词： strength     intensive soil-water     comprehensive     Infiltration     wetting-induced softening    

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ORGANIC CARBON STOCKS IN A SILTY TEXTURED SOIL FOLLOWING REINTEGRATION OF A 20 YEARS OLD × SITE INTO

《农业科学与工程前沿（英文）》 2023年 第10卷 第2期   页码 183-197 doi: 10.15302/J-FASE-2023485

摘要：

● 0.98 Mg·ha−1·yr−1 Corg accumulation under miscanthus over 26 years.

关键词： biobased energy crops     C balance     humus accumulation    

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HIGH QUALITY DEVELOPMENTAL APPROACH FOR SOIL AND WATER CONSERVATION AND ECOLOGICAL PROTECTION ON THE

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 501-511 doi: 10.15302/J-FASE-2021425

摘要：

The Loess Plateau is the core area in the Yellow River basin for implementing environmental protection and high-quality development strategies. A series of ecological projects has implemented aimed at soil and water conservation and ecological management on the Loess Plateau over the past 70 years. The effects of the ecological projects are apparent mainly through a marked increase in vegetation cover, controlled soil erosion and reduced flow of sediment into the Yellow River, continual optimization of the industrial structure and increased production from arable land, poverty alleviation and greater prosperity, and optimal allocation of space for biological organisms. Major problems have also been analyzed in ecological management including the fragile ecosystem of the region, maintaining the stability of vegetation, lower agricultural productivity and continued risk from natural disasters. Some suitable schemes and models have been developed for the coordinated development of the region through research and demonstration, striking the optimum balance between rural industry and ecology, and increased regional capacity to supply high-quality ecological products. Countermeasures to address the problems are suggested to guide ecological management and high-quality development in the future.

 

关键词： ecological management     high quality development     industrial structure     soil erosion     soil and water conservation     Loess Plateau    

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Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

《农业科学与工程前沿（英文）》 2016年 第3卷 第2期   页码 161-170 doi: 10.15302/J-FASE-2016104

摘要： Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80 mm rainfall event (80 mm·h for 60 min), 8%, 12% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treatments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400–3100 kg·hm ) is recommended for the conservation of water and soil in northern China.

关键词： infiltration     initial soil water content     rainfall simulation     soil loss     straw mulching    

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LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

Di WU, Allan A. ANDALES, Hui YANG, Qing SUN, Shichao CHEN, Xiuwei GUO, Donghao LI, Taisheng DU

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 545-558 doi: 10.15302/J-FASE-2020349

摘要： Agriculture uses a large proportion of global and regional water resources. Due to the rapid increase of population in the world, the increasing competition for water resources has led to an urgent need in increasing crop water productivity for agricultural sustainability. As the medium for crop growth, soils and their properties are important in affecting crop water productivity. This review examines the effects of soil physical, chemical, and microbial properties on crop water productivity and the quantitative relationships between them. A comprehensive view of these relationships may provide important insights for soil and water management in arable land for agriculture in the future.

关键词： crop water productivity     crop yield     soil chemical properties     soil microbial properties     soil physical properties     water consumption    

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水平衡与国土空间协调发展战略研究

胡庆芳,陈秀敏,高娟,金君良,王银堂,张建云

《中国工程科学》 2022年 第24卷 第5期   页码 63-74 doi: 10.15302/J-SSCAE-2022.05.009

摘要：

构建健康水平衡是提升水土资源匹配性、促进国土空间高质量发展的基础，而科学系统保护与集约高效利用国土空间是实现健康水平衡、保障国家水安全的根本途径。鉴于我国水资源与生产力要素分布极不匹配、国土空间发展中未有效落实量水发展的情况，本文面向生态文明建设和国土空间规划需求，以“实现健康水平衡、促进国土空间高质量发展”为目标，根据“山水林田湖草”系统治理、水陆统筹的原则，构建了以“理清约束条件、制定控制目标，完善基础设施、优化时空配置，科学严格保护、系统综合整治，集聚协调开发、高效集约利用”为主要内容的水平衡与国土空间协调发展战略。最后，提出了系统监测评价水平衡状态、提升国家尺度水土资源匹配性、优化“三生”空间划分和科学务实绿化国土等重点建议。

关键词： 健康水平衡；国土空间；协调发展；综合应对战略；生态保护修复；高效集约利用    

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Identification of abnormal operating conditions and intelligent decision system

Xiuliang LI, Junjie JIANG, Hongye SU, Jian CHU

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 456-462 doi: 10.1007/s11465-011-0224-0

摘要：

In earth pressure balance (EPB) shield construction, the “plastic flow state” is difficult to form using the soil dug in the capsule because it can cause three abnormal operating conditions, including occlusion, caking in the capsule, and spewing at the outlet of the dump device. These abnormal operating conditions can, in turn, trigger failure in tunneling, cutter-device damage, and even catastrophic incidents, such as ground settlement. This present paper effectively integrates the mechanism of abnormal operating conditions and knowledge of soil conditioning, and establishes a uniform model of identifying abnormal conditions and intelligent decision support system based on the belief rule-base system. The model maximizes knowledge in improving the soil, construction experience, and data to optimize the model online. Finally, a numerical simulation with specific construction data is presented to illustrate the effectiveness of the algorithm.

关键词： earth pressure balance (EPB) shield machine     soil pressure cabin     abnormal operating condition     belief rule-base system    

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How did Archimedes discover the law of buoyancy by experiment?

Hidetaka KUROKI

《机械工程前沿（英文）》 2016年 第11卷 第1期   页码 26-32 doi: 10.1007/s11465-016-0368-z

摘要：

After Archimedes and Vitruvius era, for more than 2000 years, it has been believed that the displaced water measurement of golden crown is impossible, and at his Eureka moment, Archimedes discovered the law of buoyancy (Proposition 7 of his principles) and proved the theft of a goldsmith by weighing the golden crown in water.

A previous study showed that a small amount of displaced water was able to be measured with enough accuracy by the introduced method. Archimedes measured the weight of displaced water. He did not find the law of buoyancy but rather specific gravity of things at the moment.

After which, Archimedes continued to measure the specific gravity of various solids and fluids. Through these measurements, he reached the discovery of the law of buoyancy directly by experiment. In this paper, the process to the discovery of Archimedes’ principle (Proposition 5) is presented.

关键词： Archimedes’ principle     buoyancy     specific gravity     Eureka     Vitruvius     displaced water     balance     floating body    

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Application of fractal theory to unsaturated soil mechanics

XU Yongfu, TONG Lixin

《结构与土木工程前沿（英文）》 2007年 第1卷 第4期   页码 411-421 doi: 10.1007/s11709-007-0056-5

摘要： The mechanical properties of unsaturated soils are a function of the saturation degree or matric suction, and can be obtained based on currently available procedures. However, each procedure has its limitations and consequently, care should be taken in the selection of a proper procedure. The fractal approach seems to be a potentially useful tool to describe hierarchical systems and is suitable to model the structure and hydraulic properties of unsaturated soils. In this paper, the soil-water characteristics, unsaturated hydraulic conductivity function, unsaturated shear strength, swelling deformation and compression were derived from the fractal model for the pore-size distribution, and were expressed by only two independent physical parameters, the fractal dimension and the air entry value. The predictions of the proposed soil-water characteristics, unsaturated hydraulic conductivity, unsaturated shear strength, swelling deformation and compression were in good agreement with published experimental data. Comparisons between the experimental results of unsaturated hydraulic conductivity and the predictions of the both fractal model and the van Genuchten-Mualem model were also performed, and it was found that the predictions of the fractal model were better than that of the van Genuchten-Mualem model.

关键词： selection     soil-water     independent physical     unsaturated     strength    

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Effects of mulching for water conservation on soil carbon, nitrogen and biological properties

Xiaomin PI, Tongxun ZHANG, Benhua SUN, Quanhong CUI, Yun GUO, Mingxia GAO, Hao FENG, David W. HOPKINS

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 146-154 doi: 10.15302/J-FASE-2017136

摘要： The effect of mulching with straw, white plastic film and black plastic film for improving soil water storage and on the soil properties was examined in a wheat-maize rotation system on Loess soil in northwestern China. All the mulches improved the water storage to some extent and led to warmer soils. However, the organic C and total N contents of the soils declined significantly under the mulches, particularly the plastic film mulches, and this could have long-term detrimental effects on soil quality and the sustainability of the some mulching practices.

关键词： biomass     carbon     mulch     nitrogen     plastic films     soil     straw     water storage    

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标题 作者 时间 类型 操作

Quantitative analysis of yield and soil water balance for summer maize on the piedmont of the North China

Jingjing WANG,Feng HUANG,Baoguo LI

期刊论文

Assessment of future climate change impacts on water-heat-salt migration in unsaturated frozen soil using

Hanli Wan, Jianmin Bian, Han Zhang, Yihan Li

期刊论文

Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

期刊论文

Experimental study on the stratum applicability and mechanisms of bubble–slurry for earth pressure balance

期刊论文

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

期刊论文

Soil-water interaction in unsaturated expansive soil slopes

ZHAN Liangtong

期刊论文

ORGANIC CARBON STOCKS IN A SILTY TEXTURED SOIL FOLLOWING REINTEGRATION OF A 20 YEARS OLD × SITE INTO

期刊论文

HIGH QUALITY DEVELOPMENTAL APPROACH FOR SOIL AND WATER CONSERVATION AND ECOLOGICAL PROTECTION ON THE

期刊论文

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

期刊论文

LINKING CROP WATER PRODUCTIVITY TO SOIL PHYSICAL, CHEMICAL AND MICROBIAL PROPERTIES

Di WU, Allan A. ANDALES, Hui YANG, Qing SUN, Shichao CHEN, Xiuwei GUO, Donghao LI, Taisheng DU

期刊论文

水平衡与国土空间协调发展战略研究

胡庆芳,陈秀敏,高娟,金君良,王银堂,张建云

期刊论文

Identification of abnormal operating conditions and intelligent decision system

Xiuliang LI, Junjie JIANG, Hongye SU, Jian CHU

期刊论文

How did Archimedes discover the law of buoyancy by experiment?

Hidetaka KUROKI

期刊论文

Application of fractal theory to unsaturated soil mechanics

XU Yongfu, TONG Lixin

期刊论文

Effects of mulching for water conservation on soil carbon, nitrogen and biological properties

Xiaomin PI, Tongxun ZHANG, Benhua SUN, Quanhong CUI, Yun GUO, Mingxia GAO, Hao FENG, David W. HOPKINS

期刊论文