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Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 218-223 doi: 10.1007/s11783-008-0037-5

摘要： To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (CHN·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cm and 20–40 cm soil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (C)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.
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INTERCROPPING SUSTAINABLY INCREASES YIELDS AND SOIL FERTILITY

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 659-661 doi: 10.15302/J-FASE-2021418

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Agricultural extension approach: evidence from an Integrated Soil Fertility Management Project in Ethiopia

Gerba LETA, Steffen SCHULZ, Girum GETACHEW ALEMU

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 427-439 doi: 10.15302/J-FASE-2020331

摘要：

Agricultural extension is an approach to rural development and agricultural transformation in which training, demonstration and technology transfer are key to reducing rural poverty, ensuring food security, and sustainably managing natural resources. During recent decades, different extension approaches have been tested and validated by the Ethiopian government and non-governmental organizations to stimulate in the agricultural extension system (AES). The most recent was a German-funded project entitled “Integrated Soil Fertility Management Project” (ISFM ), which employed a novel approach to piloting and upscaling proven technology and best practice. The purpose of this study was to analyze and document the modalities of ISFM and illustrate its effects on technology uptake and dissemination. The study used a mixed methods approach to collect data. ATLAS.ti and SPSS were used for data management and analysis. Farmer Research and Extension Groups and Farmer Field Schools were found to be central to the participation process. Also, the ISFM was found to aid technology transfer and helped to increase grain and residue yields as well as farmer livelihoods. Based on these empirical findings, it is argued that the ISFM approach and technology should be integrated and institutionalized in the mainstream AES in order to promote their extensive application.

关键词： Ethiopia     Farmer Field School     Farmer Research and Extension Group     governance     institutionalization     ISFM+ ambassador     participation    

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Effects of cotton straw amendment on soil fertility and microbial communities

Wuren HUANG, Zhihui BAI, Daniel HOEFEL, Qing HU, Xin LV, Guoqiang ZHUANG, Shengjun XU, Hongyan QI, Hongxun ZHANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 336-349 doi: 10.1007/s11783-011-0337-z

摘要： Maintaining soil fertility, while controlling pollution from excessive chemical fertilizer application is important for keeping soil productivity of sustainable agriculture. Variety of straws have been used and proven to be good soil amendments for increasing soil organic matter (OM) and a range of additional soil nutrients. However, little is known about the utilization of cotton straw for soil amendment. To better understand the mechanism behind cotton straw soil amendments, investigations were performed upon cucumber seedlings, where changes to soil nutrients and microbial communities were investigated. The results revealed that the cotton straw application promoted the cucumber seedling growth by significantly increasing the soil OM, available nitrogen, available phosphorus, and available potassium. The concentration of cotton straw was positively correlated to both the number of the culturable microorganisms and also the total microbial biomass within soil. Furthermore, assessment of cotton straw application using Biolog metabolic profiling and phospholipid fatty acid analysis revealed that such application increased the microbial community metabolic activity, and markedly changed the structure of microbial community. 16S rRNA gene clone library construction and phylogenetic analysis of soil bacteria revealed - Proteobacteria sequences dominated the cotton straw amendment soil, comprising 27.8% of the total number of analyzed sequences, while they were less represented in control soil (13.4%). On the contrary, the Sphingobacteria (7.8%) and Verrucomicrobia (2.4%) in the cotton straw amendment soil decreased after application when compared to the control soil 15.2% and 15.2%.

关键词： cotton straw     soil amendments     microbial diversity     Biolog     phospholipid fatty acid     16S rRNA gene clone library    

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A potential solution for food security in Kenya: implications of the Quzhou model in China

Xiaoqiang JIAO, Jianbo SHEN, Fusuo ZHANG

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 406-417 doi: 10.15302/J-FASE-2020359

摘要： Poor soil fertility due to low nutrient inputs is a major factor limiting grain production in Kenya. Increasing soil fertility for crop productivity in China has implications for food security in Kenya. The purpose of this study was therefore to investigate the historical patterns of grain production, nutrient inputs, soil fertility and policies in Quzhou, a typical agricultural county on the North China Plain, and to compare grain production in Quzhou County and Kenya to identify a potential approach for increasing grain production in Kenya. Grain yields in Quzhou increased from 1 to 3 t·ha between 1961 and 1987 by increasing manure application accompanied by small amounts of chemical fertilizer after soil desalinization. There was a further increase from 3 to 5 t·ha up to 1996 which can be mainly attributed to chemical fertilizer use and policy support. Hence, a beneficial cycle between soil fertility and plant growth in Quzhou grain production was developed and strengthened. In contrast, there was only a slight increase in grain yields in Kenya over this period, resulting from low soil fertility with limited external nutrient inputs, a consequence of poor socioeconomic development. It is suggested that grain yields in Kenya would likely be boosted by the development of a self-reinforcing cycling between soil fertility and plant growth with manure and chemical fertilizer use if supported by policy and socioeconomic development.

关键词： China     grain production     Kenya     soil fertility    

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Possibility of women treated with fertility-sparing surgery for non-epithelial ovarian tumors to safely

Bin Yang, Yan Yu, Jing Chen, Yan Zhang, Ye Yin, Nan Yu, Ge Chen, Shifei Zhu, Haiyan Huang, Yongqun Yuan, Jihui Ai, Xinyu Wang, Kezhen Li

《医学前沿（英文）》 2018年 第12卷 第5期   页码 509-517 doi: 10.1007/s11684-017-0554-3

摘要：

This study was performed to evaluate the oncological and reproductive outcomes of childbearing-age women treated with fertility-sparing surgery (FSS) for non-epithelial ovarian tumors in China. One hundred and forty eight non-epithelial ovarian tumor women treated with FSS between January 1, 2000 and August 31, 2015 from two medical centers in China were identified. Progression-free survival (PFS) was 88.5%, whereas overall survival (OS) was 93.9%. Univariate analysis suggested that delivery after treatment is related to PFS (P=0.023), whereas histology significantly influenced OS. Cox regression analysis suggested that only histology was associated with PFS and OS (P<0.05). Among the 129 women who completed adjuvant chemotherapy (ACT), none developed amenorrhea. Among the 44 women who desired pregnancy, 35 (79.5%) successfully had 51 gestations including 35 live births without birth defects. Non-epithelial ovarian tumors can achieve fulfilling prognosis after FSS and chemotherapy. Histology might be the only independent prognostic factor for PFS and OS. FSS followed by ACT appeared to have little or no effect on fertility. Meanwhile, postoperative pregnancy did not increase the PFS or OS. Use of gonadotropin-releasing hormone agonist was not beneficial for fertility.

关键词： malignant germ cell tumors     ovarian sex cord-stromal tumors     fertility-sparing surgery     prognosis     fertility    

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人流不全的临床特点分析及生育情况调查

罗岚蓉,李坚

《中国工程科学》 2015年 第17卷 第6期   页码 70-76

摘要：

目的：分析人流不全的临床特点，探讨其发生的高危因素，同时调查患者术后的生育及避孕情况。方法：对首都医科大学附属北京妇产医院2007年10月—2012年10月收治的55例人流不全病历进行回顾性病例分析以及电话随访了解其生育情况及避孕情况。结果：人流不全的主要临床表现为人流术后的异常阴道出血42例（42/55，76.4 %）以及月经异常13例（13/55，23.6 %），超声检查可以发现人流不全造成的宫腔内异常，但需要结合人绒毛膜促性腺激素（HCG）水平的测定以及术后的病理来诊断人流不全。B超下的清宫手术能有效地清除残留的妊娠组织，术后均未再发现宫腔残留。人流不全的高危因素中主要的客观因素为子宫过度屈曲，占23.6 %（13/55），主要的主观因素为宫颈扩张不够，占25.5 %（14/55）。二次清宫术后主要并发症为宫腔粘连，发生率为5.5 %（3/55）。55例患者术后共随访到29例患者，有17例再次妊娠，其中11例妊娠分娩，6例选择人工流产终止妊娠，未发现人流不全二次清宫对生育的明显不良影响。无生育要求的妇女均有意识采取避孕方法来避免意外妊娠。结论：人流不全的主要临床表现为手术后异常的阴道出血，通过结合尿或血的HCG检查以及B超检查，可以及时地发现人流不全。超声指导下清宫是治疗的有效办法。人流不全发生的高危因素，主要客观因素为子宫过度屈曲，主要主观因素为宫颈扩张不够。对于存在高危因素的手术采取超声指示下手术，能够有效地降低人流不全的发生率。人流不全二次清宫术后主要手术并发症为宫腔粘连，无手术并发症发生的患者，未发现明显生育能力的受损。但是对于避孕方法的选择，还需要更多的计划生育服务来帮助她们采取高效的避孕方法。

关键词： 人流不全     并发症     宫腔粘连     生育     避孕    

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广州市“单独二孩”登记群体特征分析

唐运革,李飞成,韩立薇

《中国工程科学》 2015年 第17卷 第6期   页码 82-85

摘要：

目的：分析和预测生育政策调整对个体及社会带来的各种影响，及时防范这些影响可能导致的各种社会问题。方法：以广州市2 099对“单独二孩”登记夫妻群体为例，分析这一群体人口学等方面的特征。结果：符合“可生育二孩”政策的8万个家庭中受理申请者占26.7 %，有36.5 %的夫妇未确定生育第二胎的时间，35岁以上妇女占妇女总人数的15 %。结论：“单独二孩”政策的实施不会出现“人口暴增”现象，要特别注意高龄产妇生育风险的评估和保障。

关键词： “单独二孩”     群体特征     广州市    

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Fertility outcome analysis after modified laparoscopic microsurgical tubal anastomosis

null

《医学前沿（英文）》 2011年 第5卷 第3期   页码 310-314 doi: 10.1007/s11684-011-0152-8

摘要：

Modified laparoscopic microsurgical tubal anastomosis is an alternative for microsurgical anastomosis via laparotomy to reverse sterilization in women with renewed child wish. The current study aims to evaluate the fertility outcome after modified laparoscopic microsurgical tubal anastomosis. A retrospective study was performed. Fifty-eight women who underwent modified laparoscopic microsurgical tubal anastomosis were monitored to investigate the fertility outcome and characteristics of this new technology. Of the 58 patients, the cumulative pregnancy rate (PR) in the 42 patients with follow-up data was 23.8% (10/42), 57.1% (24/42), 66.7% (28/42), and 73.8% (31/42) within 6, 12, 24, and 36 months after surgery, respectively. The intrauterine PR was 69.0% (29/42). Two patients (4.8%) had ectopic pregnancies that occurred within 24 months of surgery; three cases ended in spontaneous abortion. The delivery rate was 83.9% (26/31). The length of operating time was 1.2±0.3 h, with a range of 1.0–2.5 h (60–145 min), and the mean time was approximately 75 min. The blood loss was relatively small, between 10 and 50 ml with an average amount of 22 ml. Thus, the modified laparoscopic tubal anastomosis is a highly successful procedure and a viable alternative to open abdominal microsurgical approaches. Compared with the traditional laparoscopic tubal sterilization reversal, this modified approach has three advantages: (1) less invasive approach via a trocar reduction; (2) remodeling of tube is better performing tied together after 3–4 sutures; and (3) faster operating time.

关键词： modified laparoscopy     tubal anastomosis     microsurgery    

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Assessment of glass fiber-reinforced polyester pipe powder in soil improvement

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 742-753 doi: 10.1007/s11709-021-0732-x

摘要： This study investigates the use of glass fiber-reinforced polyester (GRP) pipe powder (PP) for improving the bearing capacity of sandy soils. After a series of direct share tests, the optimum PP addition for improving the bearing capacity of soils was found to be 12%. Then, using the optimum PP addition, the bearing capacity of the soil was estimated through a series of loading tests on a shallow foundation model placed in a test box. The bearing capacity of sandy soil was improved by up to 30.7%. The ratio of the depth of the PP-reinforced soil to the diameter of the foundation model (H/D) of 1.25 could sufficiently strengthen sandy soil when the optimum PP ratio was used. Microstructural analyses showed that the increase in the bearing capacity can be attributed to the chopped fibers in the PP and their multiaxial distribution in the soil. Besides improving the engineering properties of soils, using PP as an additive in soils would reduce the accumulation of the industrial waste, thus providing a twofold benefit.

关键词： shallow foundation     sandy soil     bearing capacity     soil improvement     pipe powder    

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Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns

Hiruy ABDU, David A. ROBINSON, Janis BOETTINGER, Scott B. JONES

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 135-145 doi: 10.15302/J-FASE-2017143

摘要： Knowledge of the spatial distribution of soil textural properties is important for determining soil moisture storage and soil hydraulic transport properties. Capturing field heterogeneity without exhaustive sampling and costly sample analysis is difficult. Our objective was to employ electromagnetic induction (EMI) mapping in low apparent electrical conductivity (EC ) soils at varying soil water contents to capture time invariant properties such as soil texture. Georeferenced EC measurements were taken using a ground conductivity meter on six different days where volumetric water content ( ) varied from 0.11 to 0.23. The 50 m × 50 m field included a subsurface gravelly patch in an otherwise homogeneous silt-loam alluvial soil. Ordinary block kriging predicted EC at unsampled areas to produce 1-m resolution maps. Temporal stability analysis was used to divide the field into three distinct EC regions. Subsequent ground-truthing confirmed the lowest conductivity region correlated with coarse textured soil parent materials associated with a former high-energy alluvial depositional area. Combining maps using temporal stability analysis gives the clearest image of the textural difference. These maps could be informative for modeling, experimental design, sensor placement and targeted zone management strategies in soil science, ecology, hydrology, and agricultural applications.

关键词： soil electrical conductivity     soil texture mapping     temporal stability analysis    

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SOIL CARBON CHECK: A TOOL FOR MONITORING AND GUIDING SOIL CARBON SEQUESTRATION IN FARMER FIELDS

《农业科学与工程前沿（英文）》 2023年 第10卷 第2期   页码 248-261 doi: 10.15302/J-FASE-2023499

摘要：

● Establishment of a rapid tool for monitoring soil carbon sequestration in farmer fields.

关键词： 4 per 1000 initiative     carbon sequestration     climate action     farmer fields     SDG13     soil organic carbon     soil testing    

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Adsorption behavior of antibiotic in soil environment: a critical review

Shiliang WANG,Hui WANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 565-574 doi: 10.1007/s11783-015-0801-2

摘要： Antibiotics are used widely in human and veterinary medicine, and are ubiquitous in environment matrices worldwide. Due to their consumption, excretion, and persistence, antibiotics are disseminated mostly via direct and indirect emissions such as excrements, sewage irrigation, and sludge compost and enter the soil and impact negatively the natural ecosystem of soil. Most antibiotics are amphiphilic or amphoteric and ionize. A non-polar core combined with polar functional moieties makes up numerous antibiotic molecules. Because of various molecule structures, physicochemical properties vary widely among antibiotic compounds. Sorption is an important process for the environment behaviors and fate of antibiotics in soil environment. The adsorption process has decisive role for the environmental behaviors and the ultimate fates of antibiotics in soil. Multiply physicochemical properties of antibiotics induce the large variations of their adsorption behaviors. In addition, factors of soil environment such as the pH, ionic strength, metal ions, and organic matter content also strongly impact the adsorption processes of antibiotics. Review about adsorption of antibiotics on soil can provide a fresh insight into understanding the antibiotic-soil interactions. Therefore, literatures about the adsorption mechanisms of antibiotics in soil environment and the effects of environment factors on adsorption behaviors of antibiotics in soil are reviewed and discussed systematically in this review.

关键词： adsorption     antibiotics     environment factors     soil    

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A simplified method for the determination of vertically loaded pile-soil interface parameters in layeredsoil based on FLAC

Jiu-jiang WU,Yan LI,Qian-gong CHENG,Hua WEN,Xin LIANG

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 103-111 doi: 10.1007/s11709-015-0328-4

摘要： The numerical analysis of pile-soil interaction commonly requires a lot of trial works to determine the interface parameters and the accuracy cannot be ensured normally. Considering this, this paper first conducts a sensitivity analysis to figure out the influence of interface parameters on the bearing behavior of a single pile in sand. Then, a simplified method for the determination of pile-soil interface parameters in layered soil is proposed based on the parameter studies. Finally, a filed loading test is used for the validation of the simplified method, and the calculated results agree well with the monitoring data. In general, the simplified method proposed in this paper works with higher accuracy and consumes less time compared with the traditional trial works, especially on the determinations of interfacial cohesive and interfacial friction angle.

关键词： determination of interface parameters     pile-soil interaction     FLAC3D     sensitivity analysis     layered soil    

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Fictitious soil pile model for dynamic analysis of pipe piles under high-strain conditions

《结构与土木工程前沿（英文）》   页码 915-934 doi: 10.1007/s11709-023-0907-8

摘要： A fictitious soil pile (FSP) model is developed to simulate the behavior of pipe piles with soil plugs undergoing high-strain dynamic impact loading. The developed model simulates the base soil with a fictitious hollow pile fully filled with a soil plug extending at a cone angle from the pile toe to the bedrock. The friction on the outside and inside of the pile walls is distinguished using different shaft models, and the propagation of stress waves in the base soil and soil plug is considered. The motions of the pile−soil system are solved by discretizing them into spring-mass model based on the finite difference method. Comparisons of the predictions of the proposed model and conventional numerical models, as well as measurements for pipe piles in field tests subjected to impact loading, validate the accuracy of the proposed model. A parametric analysis is conducted to illustrate the influence of the model parameters on the pile dynamic response. Finally, the effective length of the FSP is proposed to approximate the affected soil zone below the pipe pile toe, and some guidance is provided for the selection of the model parameters.

关键词： fictitious soil pile     soil plug     pipe piles     high-strain dynamic analysis     one-dimensional wave theory     pile dynamics    

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标题 作者 时间 类型 操作

Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

期刊论文

INTERCROPPING SUSTAINABLY INCREASES YIELDS AND SOIL FERTILITY

期刊论文

Agricultural extension approach: evidence from an Integrated Soil Fertility Management Project in Ethiopia

Gerba LETA, Steffen SCHULZ, Girum GETACHEW ALEMU

期刊论文

Effects of cotton straw amendment on soil fertility and microbial communities

Wuren HUANG, Zhihui BAI, Daniel HOEFEL, Qing HU, Xin LV, Guoqiang ZHUANG, Shengjun XU, Hongyan QI, Hongxun ZHANG

期刊论文

A potential solution for food security in Kenya: implications of the Quzhou model in China

Xiaoqiang JIAO, Jianbo SHEN, Fusuo ZHANG

期刊论文

Possibility of women treated with fertility-sparing surgery for non-epithelial ovarian tumors to safely

Bin Yang, Yan Yu, Jing Chen, Yan Zhang, Ye Yin, Nan Yu, Ge Chen, Shifei Zhu, Haiyan Huang, Yongqun Yuan, Jihui Ai, Xinyu Wang, Kezhen Li

期刊论文

人流不全的临床特点分析及生育情况调查

罗岚蓉,李坚

期刊论文

广州市“单独二孩”登记群体特征分析

唐运革,李飞成,韩立薇

期刊论文

Fertility outcome analysis after modified laparoscopic microsurgical tubal anastomosis

null

期刊论文

Assessment of glass fiber-reinforced polyester pipe powder in soil improvement

期刊论文

Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns

Hiruy ABDU, David A. ROBINSON, Janis BOETTINGER, Scott B. JONES

期刊论文

SOIL CARBON CHECK: A TOOL FOR MONITORING AND GUIDING SOIL CARBON SEQUESTRATION IN FARMER FIELDS

期刊论文

Adsorption behavior of antibiotic in soil environment: a critical review

Shiliang WANG,Hui WANG

期刊论文

A simplified method for the determination of vertically loaded pile-soil interface parameters in layeredsoil based on FLAC

Jiu-jiang WU,Yan LI,Qian-gong CHENG,Hua WEN,Xin LIANG

期刊论文

Fictitious soil pile model for dynamic analysis of pipe piles under high-strain conditions

期刊论文