检索范围：
排序： 展示方式：
《农业科学与工程前沿（英文）》 2021年 第8卷 第3期 页码 474-480 doi: 10.15302/J-FASE-2021406
European cropping systems are often characterized by short rotations or even monocropping, leading to environmental issues such as soil degradation, water eutrophication, and air pollution including greenhouse gas emissions, that contribute to climate change and biodiversity loss. The use of diversification practices (i.e., intercropping, multiple cropping including cover cropping and rotation extension), may help enhance agrobiodiversity and deliver ecosystem services while developing new value chains. Despite its benefits, crop diversification is hindered by various technical, organizational, and institutional barriers along value chains (input industries, farms, trading and processing industries, retailers, and consumers) and within sociotechnical systems (policy, research, education, regulation and advisory). Six EU-funded research projects have joined forces to boost crop diversification by creating the European Crop Diversification Cluster (CDC). This Cluster aggregates research, innovation, commercial and citizen-focused partnerships to identify and remove barriers across the agrifood system and thus enables the uptake of diversification measures by all European value-chain stakeholders. The CDC will produce a typology of barriers, develop tools to accompany actors in their transition, harmonize the use of multicriteria assessment indicators, prepare policy recommendations and pave the way for a long-term network on crop diversification.
关键词： crop rotation lock-in intercropping multiple cropping networking
《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
● 0.98 Mg·ha−1·yr−1 Corg accumulation under miscanthus over 26 years.
《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
Extracts from cotton over the whole growing season induce
Ming LANG, Rui YU, Yongqing MA, Wei ZHANG, Christopher S. P. McErlean
《农业科学与工程前沿（英文）》 2017年 第4卷 第2期 页码 228-236 doi: 10.15302/J-FASE-2017150
关键词： agricultural systems cotton crop ecology crop rotation systems weed management
Sufficient downward rotation of the christa philtri on the cleft side: a modified technique
null
《医学前沿（英文）》 2013年 第7卷 第4期 页码 510-516 doi: 10.1007/s11684-013-0299-6
Cleft lip and palate (CLP) is the most common craniofacial congenital deformity. The etiology of CLP is multifactorial and involves complex interactions between environmental and genetic factors. Millard’s rotation-advancement technique has long been considered as state-of-the-art for unilateral cleft lip repair. However, this method may leave the christa philtri on the cleft side insufficiently downward rotated, especially in wide complete clefts. In this study, we introduce a modified technique to better rotate the christa philtri on the cleft side down. The skin, muscle, and mucosa in the deformed region were dissected and separately maneuvered. Sixty patients with unilateral complete cleft lip and palate were operated with this technique. The lip height, lip length, and relative height of the christa philtri were measured for symmetry evaluation. No significant difference was observed between the relative height of the christa philtri on both sides, either immediate (P= 0.214) or 10 months after surgery (P = 0.344). The difference observed in the lip height and lip length immediately after surgery became statistically insignificant after 10 months (P = 0.104 for lip height and 0.121 for lip length). These results suggested that sufficient and stable downward rotation of the christa philtri on the cleft side can be achieved using our technique.
关键词： cleft lip and palate rotation advancement sufficient rotation christa philtri geometrically justified
Effect of RC wall on the development of plastic rotation in the beams of RC frame structures
Amar KAHIL, Aghiles NEKMOUCHE, Said BOUKAIS, Mohand HAMIZI, Naceur Eddine HANNACHI
《结构与土木工程前沿（英文）》 2018年 第12卷 第3期 页码 318-330 doi: 10.1007/s11709-017-0420-z
The objective of this study is, to interpret the influence of reinforced concrete walls addition in reinforced concrete frame structures considering behavior laws that reflects the actual behavior of such structures, by means of Castem2000computer code (pushover analysis). A finite element model is proposed in this study, using the TAKEDA modified behavior model with Timoshenko beams elements. This model is validated initially on experimental model. Then the work has focused on the behavior of a RC frame with 3 levels and three bays to better visualize the behavior of plastic hinges. Once the plastic hinge control parameters are identified (plastic rotation, ultimate curvature), a strengthening by introduction of reinforced concrete walls (RC/wall) at the ends of the reinforced concrete frame (RC/frame) has been performed. The results show that these RC walls significantly improve the behavior, by a relocation of efforts towards the central part of the beams.
关键词： RC/frame RC/wall moment curvature plastic rotation plastic hinge pushover analysis global models
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
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
IMPACTS OF CLIMATE CHANGE ON CROP PRODUCTION, PESTS AND PATHOGENS OF WHEAT AND RICE
《农业科学与工程前沿（英文）》 2022年 第9卷 第1期 页码 4-18 doi: 10.15302/J-FASE-2021432
Ongoing climate change is expected to have impacts on crops, insect pests, and plant pathogens and poses considerable threats to sustainable food security. Existing reviews have summarized impacts of a changing climate on agriculture, but the majority of these are presented from an ecological point of view, and scant information is available on specific species in agricultural applications. This paper provides an overview of impacts of climate change on two staple crops, wheat and rice. First, the direct effects of climate change on crop growth, yield formation, and geographic distribution of wheat and rice are reviewed. Then, the effects of climate change on pests and pathogens related with wheat and rice, and their interactions with the crops are summarized. Finally, potential management strategies to mitigate the direct impacts of climate change on crops, and the indirect impacts on crops through pests and pathogens are outlined. The present overview aims to aid agriculture practitioners and researchers who are interested in wheat and rice to better understand climate change related impacts on the target species.
INTEGRATING CROP AND LIVESTOCK PRODUCTION SYSTEMS—TOWARDS AGRICULTURAL GREEN DEVELOPMENT
《农业科学与工程前沿（英文）》 2021年 第8卷 第1期
RESEARCH AND APPLICATION OF CROP PEST MONITORING AND EARLY WARNING TECHNOLOGY IN CHINA
《农业科学与工程前沿（英文）》 2022年 第9卷 第1期 页码 19-36 doi: 10.15302/J-FASE-2021411
The importance of food security, especially in combating the problem of acute hunger, has been underscored as a key component of sustainable development. Considering the major challenge of rapidly increasing demands for both food security and safety, the management and control of major pests is urged to secure supplies of major agricultural products. However, owing to global climate change, biological invasion (e.g., fall armyworm), decreasing agricultural biodiversity, and other factors, a wide range of crop pest outbreaks are becoming more frequent and serious, making China, one of the world’s largest country in terms of agricultural production, one of the primary victims of crop yield loss and the largest pesticide consumer in the world. Nevertheless, the use of science and technology in monitoring and early warning of major crop pests provides better pest management and acts as a fundamental part of an integrated plant protection strategy to achieve the goal of sustainable development of agriculture. This review summarizes the most fundamental information on pest monitoring and early warning in China by documenting the developmental history of research and application, Chinese laws and regulations related to plant protection, and the National Monitoring and Early Warning System, with the purpose of presenting the Chinese model as an example of how to promote regional management of crop pests, especially of cross border pests such as fall armyworm and locust, by international cooperation across pest-related countries.
Parasitic rotation evaluation and avoidance of 3-UPU parallel mechanism
Haibo QU, Yuefa FANG, Sheng GUO
《机械工程前沿（英文）》 2012年 第7卷 第2期 页码 210-218 doi: 10.1007/s11465-012-0317-4
Based on the prototype of 3-UPU (universal-prismatic-universal joint) parallel mechanism proposed by Tsai [ ], the parasitic rotation evaluation is performed and calculated the bound of instability of SNU Seoul National University 3-UPU parallel mechanism. Through analysis of the terminal constraint system of the 3-UPU parallel mechanism, the equation about the parasitic rotation and limited clearance is presented. Then the norm of possible parasitic rotation is employed to evaluate the mechanism stability with limited clearance. The higher this number the worst is the pose, the lower it is the best it is. And the contour atlas of parasitic rotation is obtained, which can be used for further analysis and design. With the practice experiment result of SUN 3-UPU parallel mechanism, we find it’s bound of instability, which indicates there will appear the parasitic rotation when the number exceeds the bound. Finally, the method for avoidance of possible parasitic motions is presented by adding redundantly actuated limbs.
关键词： parallel mechanism 3-UPU (universal-prismatic-universal joint) parasitic motions limited clearance redundantly actuated limbs
Uncertain and multi-objective programming models for crop planting structure optimization
Mo LI,Ping GUO,Liudong ZHANG,Chenglong ZHANG
《农业科学与工程前沿（英文）》 2016年 第3卷 第1期 页码 34-45 doi: 10.15302/J-FASE-2016084
关键词： crop planting structure optimization model uncertainty multi-objective
SUSTAINABLE DEVELOPMENT OF CROP-LIVESTOCK FARMS IN AFRICA
《农业科学与工程前沿（英文）》 2021年 第8卷 第1期
Crop-livestock farms across Africa are highly variable due to in agroecological and socioeconomic factors, the latter shaping the demand and supply of livestock products. Crop-livestock farms in Africa in the 20-first century are very different from most mixed farms elsewhere in the world. African crop-livestock farms are smaller in size, have fewer livestock, lower productivity and less dependency on imported feed than farms in most countries of Europe, the Americas and the intensive agricultural systems of Asia. This paper discusses the role African crop-livestock farms have in the broader socio-agricultural economy, and how these are likely to change adapting to pressures brought on by the intensification of food systems. This intensification implies increasing land productivity (more food per hectare), often leading to more livestock heads per farm, producing fertilized feeds in croplands and importing feed supplements from the market. This discussion includes (1) the links between crop yields, soil fertility and crop-livestock integration, (2) the increasing demand for livestock products and the land resources required to meet to this demand, and (3) the opportunities to integrate broader societal goals into the development of crop-livestock farms. There is ample room for development of crop-livestock farms in Africa, and keeping integration as part of the development will help prevent many of the mistakes and environmental problems related to the intensification of livestock production observed elsewhere in the world. This development can integrate biodiversity, climate change adaptation and mitigation to the current goals of increasing productivity and food security. The inclusion of broader goals could help farmers access the level of finance required to implement changes.
REINTEGRATION OF CROP-LIVESTOCK SYSTEMS IN EUROPE: AN OVERVIEW
《农业科学与工程前沿（英文）》 2021年 第8卷 第1期
• ICLS combines the benefits of specialization with increased resilience of the system.
• Clear opportunities but also barriers for ICLS were observed.
• ICLS need to be embedded within future environmental legislation.
• ICLS systems with a range of intensities are needed to support a biodiverse landscape.
Ongoing specialization of crop and livestock systems provides socioeconomic benefits to the farmer but has led to greater externalization of environmental costs when compared to mixed farming systems. Better integration of crop and livestock systems offers great potential to rebalance the economic and environmental trade-offs in both systems. The aims of this study were to analyze changes in farm structure and review and evaluate the potential for reintegrating specialized intensive crop and livestock systems, with specific emphasis on identifying the co-benefits and barriers to reintegration. Historically, animals were essential to recycle nutrients in the farming system but this became less important with the availability of synthetic fertilisers. Although mixed farm systems can be economically attractive, benefits of scale combined with socio-economic factors have resulted in on-farm and regional specialization with negative environmental impacts. Reintegration is therefore needed to reduce nutrient surpluses at farm, regional and national levels, and to improve soil quality in intensive cropping systems. Reintegration offers practical and cost-effective options to widen crop rotations and promotes the use of organic inputs and associated benefits, reducing dependency on synthetic fertilisers, biocides and manure processing costs. Circular agriculture goes beyond manure management and requires adaptation of both food production and consumption patterns, matching local capacity to produce with food demand. Consequently, feed transport, greenhouse gas emissions, nutrient surpluses and nutrient losses to the environment can be reduced. It is concluded that reintegration of specialized farms within a region can provide benefits to farmers but may also lead to further intensification of land use. New approaches within a food system context offer alternatives for reintegration, but require strong policy incentives which show clear, tangible and lasting benefits for farmers, the environment and the wider community.
Rotation errors in numerical manifold method and a correction based on large deformation theory
Ning ZHANG, Xu LI, Qinghui JIANG, Xingchao LIN
《结构与土木工程前沿（英文）》 2019年 第13卷 第5期 页码 1036-1053 doi: 10.1007/s11709-019-0535-5
关键词： numerical manifold method rotation large deformation Green strain open-close iteration
标题 作者 时间 类型 操作
ENABLING CROP DIVERSIFICATION TO SUPPORT TRANSITIONS TOWARD MORE SUSTAINABLE EUROPEAN AGRIFOOD SYSTEMS
期刊论文
ORGANIC CARBON STOCKS IN A SILTY TEXTURED SOIL FOLLOWING REINTEGRATION OF A 20 YEARS OLD × SITE INTO A CROPROTATION
期刊论文
TRADE-OFFS IN THE DESIGN OF SUSTAINABLE CROPPING SYSTEMS AT A REGIONAL LEVEL: A CASE STUDY ON THE NORTH CHINA PLAIN
期刊论文
Extracts from cotton over the whole growing season induce
Ming LANG, Rui YU, Yongqing MA, Wei ZHANG, Christopher S. P. McErlean
期刊论文
Sufficient downward rotation of the christa philtri on the cleft side: a modified technique
null
期刊论文
Effect of RC wall on the development of plastic rotation in the beams of RC frame structures
Amar KAHIL, Aghiles NEKMOUCHE, Said BOUKAIS, Mohand HAMIZI, Naceur Eddine HANNACHI
期刊论文
Parasitic rotation evaluation and avoidance of 3-UPU parallel mechanism
Haibo QU, Yuefa FANG, Sheng GUO
期刊论文
Uncertain and multi-objective programming models for crop planting structure optimization
Mo LI,Ping GUO,Liudong ZHANG,Chenglong ZHANG
期刊论文
京公网安备 11010502051620号
