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EXPLORING THE RECYCLING OF MANURE FROM URBAN LIVESTOCK FARMS: A CASE STUDY IN ETHIOPIA
《农业科学与工程前沿(英文)》 2021年 第8卷 第1期
• Livestock manure was the main organic waste in urban and peri-urban areas.
• Manure production will increase by a factor of 3–10 between 2015–2050.
• Only 13%–38% of excreted N by livestock will be recycled in croplands.
• Intensification of urban livestock production greatly increased N surpluses.
• Reducing population growth and increasing livestock productivity needed.
Urban population growth is driving the expansion of urban and peri-urban agriculture (UPA) in developing countries. UPA is providing nutritious food to residents but the manures produced by UPA livestock farms and other wastes are not properly recycled. This paper explores the effects of four scenarios: (1) a reference scenario (business as usual), (2) increased urbanization, (3) UPA intensification, and (4) improved technology, on food-protein self-sufficiency, manure nitrogen (N) recycling and balances for four different zones in a small city (Jimma) in Ethiopia during the period 2015-2050. An N mass flow model with data from farm surveys, field experiments and literature was used. A field experiment was conducted and N use efficiency and N fertilizer replacement values differed among the five types of composts derived from urban livestock manures and kitchen wastes. The N use efficiency and N fertilizer replacement values were used in the N mass flow model.
Livestock manures were the main organic wastes in urban areas, although only 20 to 40% of animal-sourced food consumed was produced in UPA, and only 14 to 19% of protein intake by residents was animal-based. Scenarios indicate that manure production in UPA will increase 3 to 10 times between 2015 and 2050, depending on urbanization and UPA intensification. Only 13 to 38% of manure N will be recycled in croplands. Farm-gate N balances of UPA livestock farms will increase to>1 t·ha−1 in 2050. Doubling livestock productivity and feed protein conversion to animal-sourced food will roughly halve manure N production.
Costs of waste recycling were high and indicate the need for government incentives. Results of these senarios are wake-up calls for all stakeholders and indicate alternative pathways.
Microplastics in municipal wastewater treatment plants: a case study of Denizli/Turkey
《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1699-8
● High amounts of microplastics are released to receiving media from WWTPs.
关键词: Microplastics Wastewater treatment plant Removal efficiency Daily discharge
《医学前沿(英文)》 2021年 第15卷 第3期 页码 438-447 doi: 10.1007/s11684-020-0826-1
关键词: sporadic thoracic aortic dissection exome sequencing gene COL3A1 case–control study extracellular matrix
《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1716-y
● A systematic framework was developed to identify i-PPCPs for landfill leachate.
关键词: Landfill leachates PPCPs Indicator Screening criteria Source-specificity
Amin MANOUCHEHRIAN, Mohammad Fatehi MARJI, Mohsen MOHEBBI
《结构与土木工程前沿(英文)》 2012年 第6卷 第4期 页码 385-392 doi: 10.1007/s11709-012-0173-7
关键词: indirect boundary element method finite element method displacement tunnel case study
《结构与土木工程前沿(英文)》 2022年 第16卷 第2期 页码 202-213 doi: 10.1007/s11709-021-0795-8
关键词: excavated soil construction sludge geotechnical and underground engineering production classification
Pavement sustainability index for highway infrastructures: A case study of Maryland
Stella O. OBAZEE-IGBINEDION, Oludare OWOLABI
《结构与土木工程前沿(英文)》 2018年 第12卷 第2期 页码 192-200 doi: 10.1007/s11709-017-0413-y
关键词: pavement indices sustainability pavement performance flexible pavements
Wei ZENG, Jinwen ZHANG, Hongwei WANG, Hongtao ZHOU
《工程管理前沿(英文)》 2018年 第5卷 第1期 页码 88-97 doi: 10.15302/J-FEM-2018077
关键词: infrastructure mega-project supplier development critical success factors incentives case study
《工程管理前沿(英文)》 页码 563-576 doi: 10.1007/s42524-022-0198-0
关键词: Internet hospitals physicians’ online counseling online reputation offline reputation
Causations of failure in megaprojects: A case study of the Ajaokuta Steel Plant project
Oluwole Alfred OLATUNJI
《工程管理前沿(英文)》 2018年 第5卷 第3期 页码 334-346 doi: 10.15302/J-FEM-2018011
This paper uses project organizational theories to draw lessons from a historic megaproject, the Ajaokuta Steel Plant (ASP). Archival reports on the ASP were explored to identify the unique attributes of the project; the political wrangling that underplayed its evolution, its economic significance and organizational impacts. Findings suggest the goals of the ASP project were, and still are, unambiguous. Failure occurred as socio-political forces aggravated the project’s complex milestones. Stakeholders were impatient with pre-project investigations. During planning, owners ignored opinions that were contrary to their expectations. While delays lingered, pressures from the global economy weakened the project’s motivation to succeed. These combined to turn the project’s outcomes into a chaotic situation that triggered dire implications. Despite about 1400% overrun in cost, the success achieved on the plant was 28% at commissioning. Contractors remained on site until eight years after commissioning. Six key elements of the 482 items in the ASP project contract were not delivered nearly 40 years on. A simplistic look at these suggests poor planning is the main problem. However, planning issues is not entirely strange in greenfield projects. The paper draws strength from project organization theories to explain what was poor about the planning. Socrates’ generic management theory was used to explain the role of leadership in the failure of the ASP project. McGregor’s Theory X and Theory Y explain the significance of stakeholders’ integration in megaprojects. Systems and chaos theories were used to explain the sensitivity of the ASP project to uncertainties. Narratives on these combine well to inspire stakeholders of megaprojects on where and how to seek courage in making effective plans that can help achieve success in complex projects. While normative literature only recognizes project success in a definitive perspective, this study provides insights from failure as an instrument to trigger sublime reflections.
关键词: industrial projects megaprojects Nigeria project organizational theories steel plant
《农业科学与工程前沿(英文)》 2022年 第9卷 第2期 页码 295-308 doi: 10.15302/J-FASE-2021434
Since the Green Revolution cropping systems have been progressively homogenized and intensified with increasing rates of inputs such as fertilizers, pesticides and water. This has resulted in higher crop productivity but also a high environmental burden due to increased pollution and water depletion. To identify opportunities for increasing the productivity and reducing the environmental impact of cropping systems, it is crucial to assess the associated trade-offs. The paper presents a model-based analysis of how 30 different crop rotations practiced in the North China Plain could be combined at the regional level to overcome trade-offs between indicators of economic, food security, and environmental performance. The model uses evolutionary multi-objective optimization to maximize revenues, livestock products, dietary and vitamin C yield, and to minimize the decline of the groundwater table. The modeling revealed substantial trade-offs between objectives of maximizing productivity and profitability versus minimizing ground water decline, and between production of livestock products and vitamin C yield. Six strategies each defining a specific combination of cropping systems and contributing to different extents to the various objectives were identified. Implementation of these six strategies could be used to find opportunities to mitigate the trade-offs between objectives. It was concluded that a holistic analysis of the potential of a diversity cropping systems at a regional level is needed to find integrative solutions for challenges due to conflicting objectives for food production, economic viability and environmental protection.
关键词: crop rotation / food security / multi-objective optimization / water use
《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1386-6
• Aerosol transmission is an indispensable route of COVID-19 spread.
关键词: SARS-CoV-2 COVID-19 Environmental factor Aerosol transmission Epidemiologic characteristic
Impact of energy structure adjustment on air quality: a case study in Beijing, China
Bin ZHAO, Jiayu XU, Jiming HAO
《环境科学与工程前沿(英文)》 2011年 第5卷 第3期 页码 378-390 doi: 10.1007/s11783-011-0357-8
关键词: Beijing energy structure adjustment air quality Community Multiscale Air Quality Model (CMAQ) scenario
Meishan JIA, Youquan XU, Pengwang HE, Lingmin ZHAO
《工程管理前沿(英文)》 2022年 第9卷 第2期 页码 281-296 doi: 10.1007/s42524-020-0122-4
关键词: information technology construction management influential factors empirical study DEMATEL
《工程管理前沿(英文)》 页码 439-454 doi: 10.1007/s42524-022-0211-7
关键词: megaproject organizational evolution whole lifecycle management project management team
标题 作者 时间 类型 操作
Identification of variants associated with sporadic thoracic aortic dissection: a case--control study
期刊论文
Screening of indicator pharmaceuticals and personal care products in landfill leachates: a case study
期刊论文
Comparison of indirect boundary element and finite element methods A case study: Shiraz-Esfahan railway
Amin MANOUCHEHRIAN, Mohammad Fatehi MARJI, Mohsen MOHEBBI
期刊论文
Classification and quantification of excavated soil and construction sludge: A case study in Wenzhou,
期刊论文
Pavement sustainability index for highway infrastructures: A case study of Maryland
Stella O. OBAZEE-IGBINEDION, Oludare OWOLABI
期刊论文
Supplier development and its incentives in infrastructure mega-projects: A case study on Hong Kong-Zhuhai-Macao
Wei ZENG, Jinwen ZHANG, Hongwei WANG, Hongtao ZHOU
期刊论文
Investigating the effect of online and offline reputation on the provision of online counseling services: A casestudy of the Internet hospitals in China
期刊论文
Causations of failure in megaprojects: A case study of the Ajaokuta Steel Plant project
Oluwole Alfred OLATUNJI
期刊论文
TRADE-OFFS IN THE DESIGN OF SUSTAINABLE CROPPING SYSTEMS AT A REGIONAL LEVEL: A CASE STUDY ON THE NORTH
期刊论文
Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster
期刊论文
Impact of energy structure adjustment on air quality: a case study in Beijing, China
Bin ZHAO, Jiayu XU, Jiming HAO
期刊论文
critical factors that affect the application of information technology in construction management: A casestudy of China
Meishan JIA, Youquan XU, Pengwang HE, Lingmin ZHAO
期刊论文