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Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method
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作者 Suliang Ma Zeqing Meng +1 位作者 Mingxuan Chen Yuan Jiang 《Energy Engineering》 EI 2025年第1期63-84,共22页
In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimizatio... In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical dimensions.These deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s values.The optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization methods.The proposed method better balances all optimization objective functions and reduces the impact of their dimensionality.When the cost of BESS decreases by approximately 30%,its participation deepens by about 1 time.Moreover,if the price of the electrolyzer is less than 15¥/kWh or if the cost of the fuel cell drops below 4¥/kWh,their participation will increase substantially.This study aims to provide a more reasonable approach to solving multi-objective optimization problems. 展开更多
关键词 Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system
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A Genetic Algorithm Approach for Location-Specific Calibration of Rainfed Maize Cropping in the Context of Smallholder Farming in West Africa
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作者 Moussa Waongo Patrick Laux +2 位作者 Jan Bliefernicht Amadou Coulibaly Seydou B. Traore 《Agricultural Sciences》 2025年第1期89-111,共23页
Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions var... Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions varies significantly from one farmer to another, making it challenging to accurately estimate crop production through crop models. This limitation has implications for the reliability of using crop models as agricultural decision-making support tools. To support decision making in agriculture, an approach combining a genetic algorithm (GA) with the crop model AquaCrop is proposed for a location-specific calibration of maize cropping. In this approach, AquaCrop is used to simulate maize crop yield while the GA is used to derive optimal parameters set at grid cell resolution from various combinations of cultivar parameters and crop management in the process of crop and management options calibration. Statistics on pairwise simulated and observed yields indicate that the coefficient of determination varies from 0.20 to 0.65, with a yield deviation ranging from 8% to 36% across Burkina Faso (BF). An analysis of the optimal parameter sets shows that regardless of the climatic zone, a base temperature of 10˚C and an upper temperature of 32˚C is observed in at least 50% of grid cells. The growing season length and the harvest index vary significantly across BF, with the highest values found in the Soudanian zone and the lowest values in the Sahelian zone. Regarding management strategies, the fertility mean rate is approximately 35%, 39%, and 49% for the Sahelian, Soudano-sahelian, and Soudanian zones, respectively. The mean weed cover is around 36%, with the Sahelian and Soudano-sahelian zones showing the highest variability. The proposed approach can be an alternative to the conventional one-size-fits-all approach commonly used for regional crop modeling. Moreover, it has the potential to explore the performance of cropping strategies to adapt to changing climate conditions. 展开更多
关键词 Smallholder farming AquaCrop Genetics Algorithm Optimization MAIZE Burkina Faso
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An overview of the development of China’s standardization
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作者 Dai Jingyan 《China Standardization》 2025年第1期62-64,共3页
Since the end of World War II, international standards, as the common language of the world, have become an important reference for international trade and building strengths. In the current situation, it is necessary... Since the end of World War II, international standards, as the common language of the world, have become an important reference for international trade and building strengths. In the current situation, it is necessary to summarize the development history of China's standardization work. This paper reviews the formation of China's standardization concept and explores the relationship between standardization work and the shifts in the global situation. 展开更多
关键词 standardization work international standards international situation
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Third meeting of the High-Level Forum on Standardization
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《China Standardization》 2025年第1期52-52,共1页
January 29,Brussels,Belgium The 3rd meeting of the High-Level Forum on Standardization will take place on January 29,2025 in the Berlaymont building.The Executive Vice-President Stéphane Séjournéwill pe... January 29,Brussels,Belgium The 3rd meeting of the High-Level Forum on Standardization will take place on January 29,2025 in the Berlaymont building.The Executive Vice-President Stéphane Séjournéwill personally chair the meeting that will gather high-level representatives of Member States and relevant stakeholders in standardization. 展开更多
关键词 FORUM standardIZATION gather
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Research on the standardization promoting the development of intelligent manufacturing
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作者 Zhao Weiwei 《China Standardization》 2025年第1期58-61,共4页
Intelligent manufacturing is a crucial path for promoting the transformation and upgrading of the manufacturing industr y. St andardization, connecting innovation, production, market s and ser v ices, plays an indispe... Intelligent manufacturing is a crucial path for promoting the transformation and upgrading of the manufacturing industr y. St andardization, connecting innovation, production, market s and ser v ices, plays an indispensable role in the development of intelligent manufacturing. This paper aims to explore the mechanism by which standardization aids in the high-quality development of the manufacturing industry in three aspects: standards are useful tools to identify the intelligent shortcomings of manufacturing enterprises;standards provide intelligent solutions for manufacturing enterprises;standards system guides the development of manufacturing industry. It is expected to provide insights for enterprises to facilitate their intelligent construction via standards, thereby boosting the intelligent development of the industry. 展开更多
关键词 standardIZATION manufacturing industry intelligent manufacturing
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Scenario analysis of the environmental impacts of breeding structure change from the perspective of farming and breeding balance in Northeast China
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作者 Zhe Zhao Sijian Jiang Xuanchang Zhang 《Chinese Journal of Population,Resources and Environment》 2025年第1期132-142,共11页
This study uses prefecture-level city statistical data from China from 2000-2022 to measure the supply and demand of livestock manure nitrogen nutrients and calculates farmland livestock carrying capacity using the ni... This study uses prefecture-level city statistical data from China from 2000-2022 to measure the supply and demand of livestock manure nitrogen nutrients and calculates farmland livestock carrying capacity using the nitrogen nutrient balance method.We investigate nitrogen supply and demand and livestock carrying capacity in northeast China by comparing emissions from 2000-2022 over the past several decades.The poultry and livestock industry in northeast China has changed significantly over the past two decades:pigs are now the most bred animal and poultry production has increased dramatically.Regional livestock nitrogen emissions are influenced primarily by the size of the local livestock industry chain.Due to regional differences,each region has unique breeding structures.We also predict the anticipated situation in 2050 using the business-as usual scenario.High-risk livestock carrying capacity areas will be concentrated in the northeast and southeast regions,with significantly increased risk indices,compared with those of 2022,particularly in Shenyang,Fushun,and Tieling.Therefore,promoting farming and breeding,improving livestock manure utilization,and returning manure to nearby farmlands are crucial for meeting agricultural green development goals. 展开更多
关键词 Breeding structure change farming and breeding balance Agricultural green development Northeast China
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Study on the Quality Standard of Fuzheng Wangan Granules
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作者 Jiabao MA Yanmei LAN +2 位作者 Yin LIU Tingting MO Minggang WANG 《Medicinal Plant》 2025年第1期27-29,34,共4页
[Objectives]This study aims to establish the quality standard of Fuzheng Wangan granules.[Methods]The qualitative identification of Radix Bupleuri and Radix Paeoniae Alba was carried out by the thin layer chromatograp... [Objectives]This study aims to establish the quality standard of Fuzheng Wangan granules.[Methods]The qualitative identification of Radix Bupleuri and Radix Paeoniae Alba was carried out by the thin layer chromatography(TLC).The content of ginsenosides Rg1,Re and Rb was determined by the high performance liquid chromatography(HPLC).[Results]The spots of Radix Bupleuri and Radix Paeoniae Alba were clear,and the negative control had no interference.The total content of ginsenoside Rg1,Re and Rb ranged from 0.0762 to 0.0739 mg/g.[Conclusions]The method for the quality control of Fuzheng Wangan granules established in this study is stable and feasible. 展开更多
关键词 Fuzheng Wangan granules Quality standard
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Constructing a standard system of city sustainable development assessment technology based on the SDGs
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作者 Maomao Yan Feng Yang +1 位作者 Chao Li Dehua Guo 《Chinese Journal of Population,Resources and Environment》 2024年第3期275-290,共16页
Given the rapid development of China’s new urbanization,cities with different locations and varying functional positioning,resource endowments,and development stages have insufficient scientific and applicable techni... Given the rapid development of China’s new urbanization,cities with different locations and varying functional positioning,resource endowments,and development stages have insufficient scientific and applicable technical tools for implementing the United Nations Sustainable Development Goals(SDGs).City managers and policymakers must urgently establish SDG benchmarks to diagnose city development.Moreover,successful experiences from similar cities regarding sustainable development and self-improvement must be learned from to promote diversified,sustainable development across the country.Furthermore,emerging technologies such as artificial intelligence,the Internet of Things,big data and 5G are widely used in smart cities.Therefore,there is a growing need for“knowledge-based,personalized and intelligent”technologies to support monitoring,evaluation,and decision-making processes facilitating sustainable development in cities.This paper uses standardization as the theoretical support and technical basis.This approach can help clarify the sustainable development processes in China and clarify the evaluation results of and provide data on horizontal city comparisons,which can be used to develop evaluation technology for sustainable development in cities and construct a standardized system.The results provide a standard framework for intelligent assessment and decision-making regarding cities’sustainable development capabilities in China.Evaluating major international standardization institutions reveals that the practices of Chinese national standards should be fully absorbed and integrated to guide the evaluation of smart,resilient,and low-carbon cities.To this end,an indicator library of city sustainable development is proposed to provide standard evaluation technology methods.Finally,analyzing the response relationship of the indicator library to SDGs reveals the need for a standardized knowledge map of sustainable development assessment techniques and methods from the perspective of integrated management for sustainable development in cities. 展开更多
关键词 Sustainable Development Goals City sustainable development standard system Indicator library
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Research on the Index System of Old Neighborhood Renovation Based on Green Building Evaluation Standard
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作者 Yufei Que 《Journal of Architectural Research and Development》 2024年第3期140-146,共7页
With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,or... With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,organic integration,timely adoption,and correct decision-making for the transformation of old neighborhoods are pressing issues in the transformation of old neighborhoods.Therefore,this paper takes the green building evaluation standards of various countries as the research basis and support for the construction of the transformation strategy of old neighborhoods.Through the collection and comparative analysis of the indicators of green building evaluation standards,the index system of transformation is formed,and it also provides a certain foundation for the subsequent related research. 展开更多
关键词 Old neighborhoods Green building evaluation standards RENOVATION CRITERIA
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Research on the standardization of the economic terminology system of agriculture, rural areas and farmers
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作者 Wu Junting 《China Standardization》 2024年第S1期34-36,共3页
How can we standardize the economic terminology system of agriculture, rural areas and farmers based on the Chinese modernization experience? It is an issue that needs to be studied urgently by relevant experts and pr... How can we standardize the economic terminology system of agriculture, rural areas and farmers based on the Chinese modernization experience? It is an issue that needs to be studied urgently by relevant experts and practitioners. Firstly, the standardization of the terminology system should absorb the latest theoretical results to synergize the development of its doctrinal system. Secondly, it should achieve the structured and logical expression of the terminology system to enhance the systematic and scientific nature of the economics of agriculture, rural areas and farmers. Thirdly, it should pay attention to the synergy between localized experience and international paradigm to satisfy the needs of the domestic economics academia while facilitating the sharing of Chinese experience in modernization. Finally, it should establish reasonable rules for Chinese naming and its English translation of terms to achieve precision in conceptual expression and effective conversion between different languages. 展开更多
关键词 Chinese modernization AGRICULTURE rural areas and farmers economic terminology system standardIZATION rules
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Research on the construction of a standards system for the high-quality development of postpartum maternal and infant rehabilitation institutions
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作者 Xie Miaoqi Zhu Na +2 位作者 Jiang Qingqing Zhu Yufei Zheng Yingying 《China Standardization》 2024年第S1期37-41,共5页
The postpartum maternal and infant rehabilitation institution industry, an emerging sector in China, has experienced rapid grow th despite a late start. The research on the standardization of postpartum maternal and i... The postpartum maternal and infant rehabilitation institution industry, an emerging sector in China, has experienced rapid grow th despite a late start. The research on the standardization of postpartum maternal and infant rehabilitation services is crucial for fostering the high-quality development of this industry. This paper examines the current development status of postpartum maternal and infant rehabilitation institutions both domestically and internationally, reviews the existing relevant standards in China, and proposes recommendations for improvement. Using the Shenzhen Aidigong Maternity Health Management Co., Ltd. as a case study, this paper outlines a standards system for postpartum maternal and infant rehabilitation services, encompassing the standards on general basic services, operational assurances, and job. It is expected to provide strategic insights for advancing and improving China's postpartum maternal and infant rehabilitation service industry. 展开更多
关键词 postpartum care service postpartum maternal and infant rehabilitation institution standards system
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Development of a new cerebral ischemia reperfusion model of Mongolian gerbils and standardized evaluation system 被引量:3
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作者 Ying Wu Caijiao Hu +9 位作者 Zhihui Li Feiyang Li Jianyi Lv Meng Guo Xin Liu Changlong Li Xueyun Huo Zhenwen Chen Lifeng Yang Xiaoyan Du 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期48-55,共8页
Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symp... Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications. 展开更多
关键词 ISCHEMIA/REPERFUSION Mongolian gerbil standardized model system unilateral carotid occlusion
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems 被引量:1
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作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function ELEVATION Philippines Stochastic frontier analysis Technical efficiency
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The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes 被引量:1
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作者 Dian Chen Xiangming Fang +3 位作者 Yu Chen Xiaodong Zheng Zhuo Chen Rodney B.W.Smith 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期444-456,共13页
The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycle... The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition outcomes.Using China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous effects.We exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition outcomes.Our results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of age.Specifically,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage points.Additional analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition outcomes.We also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor areas.Our findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality. 展开更多
关键词 Rural Minimum Living standard Guarantee NUTRITION height-to-age z-scores STUNTING rural China
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A holistic strategy for quality and safety control of traditional Chinese medicines by the “iVarious” standard system 被引量:17
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作者 Anzhen Chen Lei Sun +3 位作者 Hang Yuan Aiying Wu Jingguang Lu Shuangcheng Ma 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第5期271-279,共9页
An effective quality control system is the key to ensuring the quality, safety and efficacy of traditional Chinese medicines(TCMs). However, the current quality standard research lacks top-level design and systematic ... An effective quality control system is the key to ensuring the quality, safety and efficacy of traditional Chinese medicines(TCMs). However, the current quality standard research lacks top-level design and systematic design,mostly based on specific technologies or evaluation methods. To resolve the challenges and questions of quality control of TCMs, a brand-new quality standard system, named "iVarious", was proposed. The system comprises eight elements in a modular format. Meaning of every element was specifically illustrated via corresponding research instances. Furthermore, frankincense study was taken as an example for demonstrating standards and research process, based on the "i Various" system. This system highlighted a holistic strategy for effectiveness,security, integrity and systematization of quality and safety control standards of TCMs. The establishment of"i Various" integrates multi-disciplinary technologies and progressive methods, basis elements and key points of standard construction. The system provides a novel idea and technological demonstration for regulation establishment of TCMs quality standards. 展开更多
关键词 iVarious QUALITY standard system TRADITIONAL CHINESE MEDICINES (TCMs) QUALITY and safety control HOLISTIC STRATEGY
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The Evolution of Organic Carbon in Chinese Mollisol Under Different Farming Systems: Validation and Prediction by Using Century Model 被引量:6
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作者 GAO Chong-sheng WANG Jian-guo ZHANG Xing-yi SUI Yue-yu 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1490-1496,共7页
Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processi... Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processing and assorting concerning data, based on clarifying parameters of Century model need, combined with best use of recorded data of field management, observed data of long-term experiments, climate, soil, and biology, and achieved results from Hailun Agro-Ecological Experimental Station, Chinese Academy of Sciences. The results were showed as follows: Before reclamation, SOC content was around 58.00 g kg^-1, SOC content dropped quickly in early years, and then decreased slowly after reclamation. SOC content was around 34.00 g kg^-1 with a yearly average rate of 8.91‰ decrease before long-term experiments was established. After a long-term experiment, SOC would change under different farming systems. Shift farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 30.19 g kg^-1, with a yearly average rate of 5.97‰; by 100-year model simulation, SOC content decreased to 24.31 g kg^-1, with a yearly average rate of 3.36‰. Organic farming system changed as follows: By 20-year model simulation, SOC content decreased slowly from 34.03 to 33.39 g kg^-1, with a yearly average rate of 0.95‰, 5‰ less than that of shift farming system; by 100-year model simulation, SOC content decreased to 32.21 g kg^-1, with a yearly average rate of 0.55‰. "Petroleum" farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 32.88 g kg^-1, with a yearly average rate of 1.72‰, much more than that of organic farming system; by 100-year model simulation, SOC content decreased to 30.89 g kg^-1, with a yearly average rate of 0.96‰. Combined "petroleum"-organic farming system changed as follows: By 20-year model simulation, SOC content was increased slightly; by 100-year model simulation, SOC content increased from 34.03 to 34.41g kg^-1, with a yearly average rate of 0.11‰. The above results provided an optimal way for maintaining SOC in Chinese mollisol farmland: To increase, as much as possible within agro-ecosystem, soil organic matter returns such as crop stubble, crop litter, crop straw or stalk, and manure, besides applying chemical nitrogen and phosphorous, which increased system productivity and maintained SOC content as well. Also, the results provided a valuable methodology both for a study of CO2 sequestration capacity and for a target fertility determination in Chinese mollisol. 展开更多
关键词 Century model Chinese mollisol farmland soil organic carbon various farming systems PREDICTION
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The Effect of Land Degradation on Farm Size Dynamics and Crop-Livestock Farming System in Ethiopia: A Review 被引量:3
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作者 Assemu Tesfa Shigdaf Mekuriaw 《Open Journal of Soil Science》 2014年第1期1-5,共5页
Ethiopia is among the poorest countries in which poverty, land and resource degradation appear to feed off each other. The irony is that Ethiopia is a country with high biodiversity and distinctive ecosystems and the ... Ethiopia is among the poorest countries in which poverty, land and resource degradation appear to feed off each other. The irony is that Ethiopia is a country with high biodiversity and distinctive ecosystems and the natural resource base is critical to the economy and the livelihood of a high percentage of the population. Being the owner of varying agro ecology, the country’s agricultural production system had practiced for decades with a maximum potential. However, because of the presence of interrelated problems, the productivity had not sustained as its potential. From the interrelated problems, land degradation takes the first and challengeable problem in many countries. Land degradation refers to a temporary or permanent decline in the productive capacity of the land, or its potential for environmental management as a result;the long-term biological and environmental potential of the land has been compromised. Land degradation in the Ethiopian highlands (i.e. areas above 1500 m.a.s.l.) has been a concern for many years and is a great threat for the future that requires great effort and resources to ameliorate. It had adverse effect on lowering of livestock production by shrinking grazing land, the fertile soil types were washed and the grazing land was dominantly covered by unpalatable pastures and grasses which had low nutritive value and fertility for crop-livestock production system. In other cases, degradation induces farmers to convert land to lower-value uses;for instance, cropland converted to grazing land, or grazing lands converted to shrubs or forests. Equitable and secure access to land is a critical factor for the rural poor, especially livestock owners, who depend on agriculture and animal-related activities for their livelihood. Having secure access to land for agriculture and pastoral activities reduces their vulnerability and enhances their opportunities to invest in land for agriculture and livestock activities. Historical patterns of feudal ownership of land followed by government ownership and despite policy change uncertain status of land ownership. These land distribution and ownership patterns coupled with continuous fragmentations and degradation disrupt the balance between crop, livestock, and forest production. These things nowadays enforce Ethiopian farmers to put more land into crop production than working on livestock sector. Livelihoods are complex, dependent on animal and crop production based on land and water resources, with emerging market opportunities. And from year to year, the size of farms is getting minimized because of land degradation and segmentations, and these make a change in farm size dynamics and farming shift. Currently, there is a great scenario towards the land policy pattern and agricultural production system, which is the backbone of the country’s economy. Therefore, the aim of this paper is to review the effect of land degradation on farm size dynamics and crop-livestock production since the impact of these things is not well measured. 展开更多
关键词 Crop-Livestock farming system FARMERS Farm Size DYNAMICS Land Degradation
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Efficiency and productivity analysis of vegetable farming within root and tuber-based systems in the humid tropics of Cameroon 被引量:1
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作者 Ajapnwa Akamin Jean-Claude Bidogeza +1 位作者 Jules Rene Minkoua N Victor Afari-Sefa 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第8期1865-1873,共9页
The study analyzes the technical efficiency of vegetable farmers in root and tuber-based farming systems within selected sites of the humid tropics of Cameroon. Multistage sampling was used to collect primary data fro... The study analyzes the technical efficiency of vegetable farmers in root and tuber-based farming systems within selected sites of the humid tropics of Cameroon. Multistage sampling was used to collect primary data from a cross-section of vegetable farmers drawn from eight selected sites in Santa sub division, Northwest region of Cameroon. Stochastic frontier analysis was used to estimate the technical efficiency of vegetable farmer and to examine its determinants. The results showed that farmyard manure was the most productive factor input, followed by farm equipment and labor. The mean technical efficiency level was 67%, revealing production shortfalls and indicating possibilities of significantly increasing production with the current input Jevels. Female, as well as more educated farmers were found to be significantly more efficient than their counterparts. The results also showed that farmers become less technical efficient as farm sizes become larger. Our study findings suggest that smallholder farmers' access to manure, farm implements, and increased women participation in vegetable farming, will produce huge payoffs in vegetable production efficiency in Cameroon. 展开更多
关键词 technical efficiency vegetable productivity farming systems intensification crop diversification stochasticfrontier analysis
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Sustainability Evaluation of Different Systems for Sea Cucumber(Apostichopus japonicus) Farming Based on Emergy Theory 被引量:2
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作者 WANG Guodong DONG Shuanglin +2 位作者 TIAN Xiangli GAO Qinfeng WANG Fang 《Journal of Ocean University of China》 SCIE CAS 2015年第3期503-510,共8页
Emergy analysis is effective for analyzing ecological economic systems. However, the accuracy of the approach is af- fected by the diversity of economic level, meteorological and hydrological parameters in different r... Emergy analysis is effective for analyzing ecological economic systems. However, the accuracy of the approach is af- fected by the diversity of economic level, meteorological and hydrological parameters in different regions. The present study evalu- ated the economic benefits, environmental impact, and sustainability of indoor, semi-intensive and extensive farming systems of sea cucumber (Apostichopus japonicus) in the same region. The results showed that A. japonicus indoor farming system was high in input and output (yield) whereas pond extensive farming system was low in input and output. The output/input ratio of indoor fann- ing system was lower than that of pond extensive farming system, and the output/input ratio of semi-intensive farming system fell in between them. The environmental loading ratio of A.japonicus extensive fanning system was lower than that of indoor farming sys- tem. In addition, the emergy yield and emergy exchange ratios, and emergy sustainability and emergy indexes for sustainable devel- opment were higher in extensive farming system than those in indoor farming system. These results indicated that the current exten- sive farming system exerted fewer negative influences on the environment, made more efficient use of available resources, and met more sustainable development requirements than the indoor farming system. A. japonicus farming systems showed more emergy benefits than fish fanning systems. The pond fanning systems ofA. japonicus exploited more free local environmental resources for production, caused less potential pressure on the local environment, and achieved higher sustainability than indoor farming system. 展开更多
关键词 Apostichopusjaponicas farming systems emergy theory SUSTAINABILITY
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Variations of Farming Systems and Their Impacts on Surface Water Environment in Past 60 Years in Intensive Agricultural Area of Taihu Region, China 被引量:1
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作者 Xinyan Li Hengpeng Li +3 位作者 Guishan Yang Nkotagu Hudson Huan Zhang Xiaofei Nie 《Journal of Water Resource and Protection》 2015年第8期647-658,共12页
Based on agricultural nitrogen (N) balance model and field experiments, the impacts of farming system changes of Taihu Region of China on surface water environment were studied. During past 60 years, farming systems c... Based on agricultural nitrogen (N) balance model and field experiments, the impacts of farming system changes of Taihu Region of China on surface water environment were studied. During past 60 years, farming systems changed greatly in Taihu Region. The traditional method of manure collection and application was replaced by chemical fertilizer utilization gradually. Chemical N fertilization intensity decreased greatly due to the abolition of “3 crops per year” and reduction of cropland area in 1990-2010. Crops depleting soil fertility increased, while those improving soil fertility decreased, leading to an excessive dependence on chemical fertilizer application, which increased the risks of soil N loss to surface water environment in Taihu region. However, field experiments showed that the agricultural N loss with runoff only accounted for 2% of fertilizer N application rate. The majority of N was exported by crop harvesting. Our findings showed that the agricultural N loss might not be the main source of N pollution in Lake Tai after 2000. To control N pollution of Lake Tai, more attention should be paid to industrial and domestic wastewater from urban and rural areas, wastes from livestock and poultry breeding, bait input for aquaculture, etc in the Taihu Region, China. 展开更多
关键词 farming systems Agricultural Nitrogen BALANCE FERTILIZATION Environmental Pollution Taihu
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